JP2012182229A - Semiconductor device manufacturing method, insulation film and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method which can efficiently manufacture a highly reliable semiconductor device which includes an insulation film made from a material containing a polymer of a polymerizable compound which is an organic compound having a chemical structure not containing Si, and in which a problem of increase in a dielectric constant is prevented.SOLUTION: A semiconductor manufacturing method of the present invention comprises: an insulation film formation process of forming an insulation film made from a material containing a polymer of a polymerizable compound which is an organic compound having a chemical structure not containing Si, so as to cover a semiconductor substrate on which elements are formed; a nitrogen-based etching process of performing plasma etching on the insulation film by using a nitrogen-based gas; and an oxygen content ratio reduction process of reducing an oxygen content ratio of the insulation film on which the nitrogen-based etching is performed.

Description

  The present invention relates to a semiconductor device manufacturing method, an insulating film, and a semiconductor device.

  In the field of electronic materials, as semiconductor devices become more highly integrated, faster and have higher performance, delay time due to increased resistance between wires and increased capacitance of semiconductor integrated circuits has become a major problem. In order to reduce the delay time and increase the speed of the semiconductor device, it is necessary to use an interlayer insulating film (insulating film) having a low dielectric constant for the circuit.

  In the manufacture of a semiconductor device, patterning of an interlayer insulating film (insulating film) is necessary, but the patterning is usually performed by plasma etching using a nitrogen-based gas (a mixed gas of nitrogen and hydrogen or ammonia gas). However, there is a problem that the dielectric constant of the interlayer insulating film (insulating film) is increased by the plasma etching. Such a problem is particularly noticeable in an inorganic interlayer insulating film (insulating film) composed of a compound having a siloxane skeleton. In order to solve such a problem, an interlayer damaged by plasma etching is considered. A technique for repairing damage by using a composition containing a silane compound for an insulating film (insulating film) has been proposed (see, for example, Patent Document 1).

  The problem of an increase in the dielectric constant of the interlayer insulating film (insulating film) as described above is that an organic interlayer insulating film (insulating film) composed of an organic compound (especially a compound not containing Si as a basic skeleton) Is smaller than an inorganic interlayer insulating film (insulating film) composed of a compound having a siloxane skeleton, and has not been considered so far.

  However, the organic interlayer insulating film (insulating film) also requires a further decrease in dielectric constant in order to improve the performance and reliability of the semiconductor device.

JP 2006-114719 A

  An object of the present invention is to provide an insulating film made of a material containing a polymer of a polymerizable compound, which is an organic compound having a chemical structure not containing Si, and has a high reliability in which the problem of an increase in dielectric constant is prevented. An object of the present invention is to provide a semiconductor device, to provide a manufacturing method capable of efficiently manufacturing the semiconductor device, and to provide an insulating film that can be suitably used for manufacturing the semiconductor device.

Such an object is achieved by the present invention described in the following (1) to (12).
(1) Insulating film forming step of forming an insulating film made of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si so as to cover a semiconductor substrate on which an element is formed When,
A nitrogen-based etching step of plasma etching the insulating film using a nitrogen-based gas;
A method for manufacturing a semiconductor device, comprising: an oxygen content reduction step for reducing the oxygen content of the insulating film subjected to the nitrogen-based etching step.

  (2) A resist film forming step for forming a resist film so as to cover the insulating film between the insulating film forming step and the nitrogen-based etching step; and exposing the resist film using a photomask. The method for manufacturing a semiconductor device according to (1), further comprising: a resist film patterning step of performing development processing and patterning the resist film.

  (3) Between the insulating film forming step and the resist film forming step, the surface of the insulating film is made of at least one material selected from the group consisting of SiO, SiN, SiC, SiCN and SiOC. The method for manufacturing a semiconductor device according to (2), further including a cap layer forming step of forming a cap layer.

  (4) The above (3) further comprising a fluorine-based etching step of etching the cap layer using a fluorine-based gas with the resist film as a mask between the resist film patterning step and the nitrogen-based etching step. The manufacturing method of the semiconductor device of description.

  (5) The above-mentioned (1) further comprising a barrier metal layer forming step of forming a barrier metal layer for preventing diffusion of constituent components of the wiring layer on the surface side on which the insulating film is provided after the oxygen content reduction step. ) To (4).

  (6) The wiring layer forming step of forming the wiring layer in the groove portion of the insulating film covered with the barrier metal layer and further covering the surface of the barrier metal layer with the constituent material of the wiring layer. (5) The manufacturing method of the semiconductor device as described in (5).

  (7) The method of manufacturing a semiconductor device according to (6), further including a polishing step of removing a portion formed of the constituent material of the wiring layer and provided outside the groove by polishing using a CMP method.

(8) The method for manufacturing a semiconductor device according to any one of (1) to (7), wherein in the oxygen content reduction step, plasma treatment is performed in an atmosphere containing H ₂ and He.

  (9) The semiconductor device according to any one of (1) to (8), wherein an O (oxygen atom) content in the vicinity of the surface of the insulating film after the oxygen content reduction step is 5.4 atomic% or less. Manufacturing method.

(10) An insulating film composed of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si, and subjected to plasma etching,
An insulating film having an oxygen content near the surface of 5.4 atomic% or less.

  (11) A semiconductor device manufactured using the method according to any one of (1) to (9).

  (12) A semiconductor device comprising the insulating film according to (10).

  According to the present invention, an insulating film made of a material containing a polymer of a polymerizable compound, which is an organic compound having a chemical structure that does not contain Si, is provided and is highly reliable in which the problem of increase in dielectric constant is prevented. It is possible to provide a semiconductor device, to provide a manufacturing method capable of efficiently manufacturing the semiconductor device, and to provide an insulating film that can be suitably used for manufacturing the semiconductor device.

It is a longitudinal cross-sectional view which shows suitable embodiment of the manufacturing method of a semiconductor device. It is a longitudinal cross-sectional view which shows suitable embodiment of the manufacturing method of a semiconductor device. It is a longitudinal cross-sectional view which shows suitable embodiment of the manufacturing method of a semiconductor device. 4 is an infrared spectrum chart showing the results of infrared spectroscopy (FT-IR) for the insulating film of Example 1. FIG.

Hereinafter, the present invention will be described in detail.
<Method for Manufacturing Semiconductor Device>
First, a method for manufacturing a semiconductor device of the present invention will be described. 1 to 3 are longitudinal sectional views showing a preferred embodiment of a method for manufacturing a semiconductor device. In the following description, the upper side in FIGS. 1 to 3 is referred to as “upper” and the lower side is referred to as “lower”.

  As shown in FIGS. 1 to 3, in the manufacturing method of the present embodiment, a semiconductor substrate preparation step (1 a) for preparing a semiconductor substrate 1 on which elements are formed, and a silicon-containing film 2 is formed on the surface of the semiconductor substrate 1. A silicon-containing film forming step (1b) and an insulating film (interlayer insulating film) made of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si on the surface of the silicon-containing film 2 And forming a cap layer 4 made of at least one material selected from the group consisting of SiO, SiN, SiC, SiCN and SiOC on the surface of the insulating film 3. A resist layer forming step (1d), a resist film forming step (1e) for forming a resist film 8 on the surface of the cap layer 4, and exposure / development processing is performed on the resist film 8 using a photomask. A resist film patterning step (1f) for patterning the film 8, a fluorine-based etching step (1g) for etching the cap layer 4 using a fluorine-based gas using the resist film 8 as a mask, and a nitrogen layer using the cap layer 4 as a mask. A nitrogen-based etching step (1h) for plasma-etching the insulating film 3 using a gas to form an opening (groove), and an oxygen-containing ratio for reducing the oxygen content of the insulating film 3 subjected to the nitrogen-based etching step A rate reduction step (1i), a barrier metal layer formation step (1j) for forming a barrier metal layer 6 for preventing diffusion of constituent components of the wiring layer 7 to be described later, on the surface side on which the insulating film 3 is provided, The surface side on which the metal layer 6 is provided is covered with the constituent material of the wiring layer 7, and the wiring layer 7 is formed in the groove of the insulating film 3 covered with the barrier metal layer 6. A wiring layer forming step (1k) for covering the surface of the ametal layer 6 (a surface parallel to the main surface of the semiconductor substrate 1) with the constituent material of the wiring layer 7, and a portion made of the wiring material and provided outside the groove portion And a polishing step (1l) to be removed by polishing by the CMP method.

[Silicon-containing film formation process]
The silicon-containing film forming step can be suitably performed using a vapor phase film forming method. In the present invention, the silicon-containing film 2 may be any material known to those skilled in the art as a barrier film and an etch stopper film, but SiCN or SiC is preferably used.

[Insulating film formation process]
The insulating film forming step is performed by applying a film forming composition to the surface of the silicon-containing film 2 by a method such as spin coating using a spinner, spray coating using a spray coater, dipping, printing, roll coating, or the like. Can be suitably performed.

  The insulating film 3 can be formed by subjecting the film-forming composition applied to the surface of the silicon-containing film 2 to a treatment (baking treatment) such as heating or irradiation with active energy rays.

  By performing such a baking treatment, the unreacted polymerizable reactive group of the polymerizable compound constituting the film-forming composition or the prepolymer obtained by partially polymerizing the polymerizable compound undergoes a polymerization reaction, and the polymer ( An insulating film 3 composed of a cured product is obtained.

  Prior to the baking treatment, for example, a treatment (desolvation treatment) for removing the solvent from the film-forming composition applied on the silicon-containing film 2 may be performed. Such solvent removal treatment can be performed, for example, by heat treatment, reduced pressure treatment, or the like.

  The baking treatment is preferably performed under conditions of, for example, a processing temperature: 200 to 450 ° C. and a processing time of 1 to 60 minutes, and a processing temperature of 250 to 400 ° C. and a processing time of 5 to 30 minutes. More preferred. In the baking step, heat treatments with different conditions may be combined.

  The insulating film 3 can also be formed in such a manner that a resin film (insulating film) separately prepared as a dry film is laminated on the silicon-containing film 2 in advance. More specifically, using a film forming composition, a resin film (insulating film) is formed on a member and dried in advance to obtain a dry film. The dry film is peeled from the member, The insulating film 3 may be formed by laminating on the silicon-containing film 2 and applying heat and / or radiation.

  The insulating film 3 formed on the silicon-containing film 2 in this step is made of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si. Such an insulating film is different in etching rate from the silicon-containing film 2 and the cap layer 4 as compared with an insulating film made of a compound having a chemical structure containing Si (in particular, a polysiloxane compound having Si as a basic skeleton). And has a feature of excellent workability in the semiconductor device manufacturing process.

The dielectric constant of the insulating film 3 formed in this step is preferably 2.80 or less, more preferably 2.40 or less, and even more preferably 2.30 or less. Thereby, it is possible to further increase the speed of the semiconductor device. The dielectric constant of the insulating film 3 can be obtained using, for example, an automatic mercury probe CV measuring device SSM495 manufactured by Nippon SSM Co., Ltd.
The composition (film forming composition) used for forming the insulating film 3 will be described in detail later.

  The thickness of the insulating film 3 is preferably 0.03 to 20 μm, more preferably 0.04 to 10 μm, and further preferably 0.05 to 0.7 μm. Thereby, the reliability of the patterned insulating film 3 and the reliability of the semiconductor device 100 manufactured using the insulating film 3 can be made particularly high. On the other hand, when the film thickness of the insulating film 3 is less than the lower limit value, pinholes and unintentional variations in film thickness are likely to occur. Moreover, when the film thickness of the insulating film 3 exceeds the upper limit, cracks are likely to occur in the insulating film 3 due to heat treatment during the manufacturing process of the semiconductor device.

[Cap layer forming step]
The cap layer 4 formed in the cap layer forming step is composed of at least one material selected from the group consisting of SiO, SiN, SiC, SiCN, and SiOC.
The cap layer forming step can be suitably performed using a vapor phase film forming method.

[Resist film forming step]
The resist film forming step can be performed using, for example, various coating methods, and among them, methods such as spin coating using a spinner, spray coating using a spray coater, dipping, printing, roll coating, etc. are preferably applied. can do.

[Resist film patterning process]
The resist film patterning step can be performed by performing exposure / development processing usually performed by a general photolithography method.

[Fluorine etching process]
The fluorine-based etching process is performed by an etching method (reactive ion etching method) using a fluorine-based gas such as CF ₄ as a processing gas. Thereby, it is possible to suitably etch the cap layer 4 while preventing the insulating film 3 from being damaged.

[Nitrogen etching process]
The nitrogen-based etching step is performed by an etching method (reactive ion etching method) using a nitrogen-based gas (a mixed gas of nitrogen and hydrogen or ammonia gas) as a processing gas. Usually, in this step, the resist film 8 on the cap layer 4 can be removed by ashing together with the etching of the insulating film 3.

[Oxygen content reduction step]
By the way, when etching (nitrogen-based etching) using the above-described nitrogen-based gas (mixed gas of nitrogen and hydrogen or ammonia gas) is performed, the insulating film is damaged and the dielectric constant increases. It was known that there was a problem of end.

Therefore, the present inventor has intensively studied for the purpose of reducing the dielectric constant of the insulating film, which has been damaged by nitrogen-based etching and whose dielectric constant has increased, again. As a result, the nitrogen-based etching increases the content of oxygen atoms in the insulating film, which is considered to increase the dielectric constant of the insulating film, and the insulating film that has been treated with nitrogen-based etching. It has been found that the above object can be achieved by subjecting the film to a treatment for reducing the oxygen content of the insulating film. Note that the content of oxygen atoms in the insulating film increases by performing nitrogen-based etching because the radical concentration of the insulating film increases by performing nitrogen-based etching, and the state is maintained for a relatively long period of time. This is considered to be due to the reaction of the radicals with oxygen (O ₂ ) contained in the air when the insulating film is opened to the atmosphere after nitrogen etching.

The oxygen content reduction process performed in this process (oxygen content reduction process) may be any process as long as the oxygen content of the insulating film 3 is reduced. For example, an atmosphere containing H ₂ and He Plasma treatment performed in an atmosphere containing H ₂ and Ar, Plasma treatment conducted in an atmosphere containing H ₂ and Ne, Plasma treatment conducted in an atmosphere containing H ₂ alone, and an atmosphere containing H ₂ and He Heat treatment performed in an atmosphere containing H ₂ and Ar, heat treatment performed in an atmosphere containing H ₂ and N ₂ , heat treatment performed in an atmosphere containing H ₂ alone, and the like. Among these, the oxygen content reduction process performed in this step (oxygen content reduction process) is preferably a plasma process (hereinafter also referred to as “H ₂ He plasma treatment”) performed in an atmosphere containing H ₂ and He. . Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  The treatment temperature in the oxygen content reduction treatment is preferably 150 to 400 ° C, more preferably 200 to 380 ° C, and further preferably 250 to 370 ° C. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  The treatment time for the oxygen content reduction treatment is preferably 5 to 60 seconds, and more preferably 10 to 50 seconds. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  The RF top power in the oxygen content reduction process is preferably 50 to 1000 W. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  Moreover, it is preferable that RF bottom power in an oxygen content rate reduction process is 0-300W, and it is more preferable that it is 0-50W. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  Moreover, it is preferable that the pressure at the time of an oxygen content rate reduction process is 1-400 Pa, and it is more preferable that it is 1-300 Pa. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  In addition, the flow rate of hydrogen gas during the oxygen content reduction treatment is preferably 0.01 to 0.80 sccm, and more preferably 0.04 to 0.50 sccm. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  In addition, the flow rate of helium gas during the oxygen content reduction treatment is preferably 1 to 20 sccm, and more preferably 2 to 10 sccm. Thereby, the oxygen content of the insulating film 3 can be made particularly low easily and reliably.

  In this step, the O (oxygen atom) content in the vicinity of the surface of the insulating film 3 after this step (for example, the O content when the detection depth is 5 nm from the surface) is 5.4 atomic% or less. It is preferable to carry out the treatment, more preferably 4.5 atomic percent or less, and even more preferably 3.1 atomic percent or less. Thereby, the reliability of the patterned insulating film 3 and the reliability of the semiconductor device 100 manufactured using the insulating film 3 can be made particularly high.

  When the dielectric constant of the insulating film 3 immediately after the nitrogen-based etching step is k1, and the dielectric constant of the insulating film 3 immediately after this step (oxygen content reduction step) is k2, the relationship of k1-k2 ≧ 0.10 is satisfied. It is preferable that the relationship of k1-k2 ≧ 0.20 is satisfied. Thereby, the reliability of the patterned insulating film 3 and the reliability of the semiconductor device 100 manufactured using the insulating film 3 can be made particularly high.

  Further, when the dielectric constant of the insulating film 3 immediately after the insulating film forming step is k0 and the dielectric constant of the insulating film 3 immediately after this step (oxygen content reduction step) is k2, the relationship of k2-k1 ≦ 0.10 is established. Satisfaction is preferred. Thereby, the reliability of the patterned insulating film 3 and the reliability of the semiconductor device 100 manufactured using the insulating film 3 can be made particularly high.

  The dielectric constant of the insulating film 3 after this step is preferably 2.90 or less, more preferably 2.50 or less, further preferably 2.40 or less, and 2.30 or less. Is most preferred. Thereby, it is possible to further increase the speed of the semiconductor device. The dielectric constant of the insulating film 3 can be obtained using, for example, an automatic mercury probe CV measuring device SSM495 manufactured by Nippon SSM Co., Ltd.

[Barrier metal layer formation process]
The barrier metal layer forming step can be performed by a vapor deposition method such as a PVD method.

  As a constituent material of the barrier metal layer 6, for example, at least one selected from the group consisting of Ta, Ti, TaN, TiN, and WN can be used. By using such a material, the function of the barrier metal layer 6 that prevents the diffusion of the constituent components of the wiring layer 7 can be more effectively exhibited.

[Wiring layer forming process]
The wiring layer forming step is preferably performed in combination with a vapor deposition method such as PVD and a wet plating method such as electric field plating. Thereby, the formation efficiency of the wiring layer 7 can be made particularly excellent while the adhesion of the wiring layer 7 to the barrier metal layer 6 is sufficiently excellent. The constituent material of the wiring layer 7 is not particularly limited, but copper (Cu) is preferably used.

[Polishing process]
The polishing step is performed by a CMP method (chemical mechanical polishing method).

  In the polishing step, as the polishing composition, for example, particles composed of a cocondensate of polymethyl methacrylate and divinylbenzene, hydrogen peroxide, glycine, benzotriazole, and polyoxyethylene lauryl ether sulfate ammonium salt And those containing water, polyoxyethylene oleyl ether ammonium sulfate, oxalic acid, colloidal silica, benzotriazole, hydrogen peroxide, water, and the like can be used.

In this step, for example, two or more processes under different conditions may be performed.
The semiconductor device 100 is obtained through the steps as described above.

Hereinafter, the film forming composition used for forming the insulating film 3 will be described in detail.
The composition (film forming composition) used for forming the insulating film 3 forms the insulating film 3 made of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si. Any polymerizable compound may be used as long as it can be used, and a polymerizable compound having a partial structure A including an adamantane cage structure and a polymerizable reactive group B contributing to the polymerization reaction in the molecule, and It is preferable that the polymerizable compound includes a polymer obtained by partially polymerizing, and particularly includes a polymerizable compound X and / or a polymer obtained by partially polymerizing the polymerizable compound X as described below. It is preferable that As a result, the dielectric constant of the insulating film 3 after the oxygen content reduction step can be easily and reliably made particularly low, and the reliability of the patterned insulating film 3 and the insulating film 3 are manufactured. The reliability of the semiconductor device 100 can be made particularly high.

  Hereinafter, a polymerizable compound having a partial structure A including an adamantane cage structure and a polymerizable reactive group B contributing to a polymerization reaction in the molecule and / or a polymer in which the polymerizable compound is partially polymerized In particular, a composition (film forming composition) containing the polymerizable compound X and / or a polymer obtained by partially polymerizing the polymerizable compound X will be described in detail.

[1] Polymerizable compound X
The polymerizable reactive group B of the polymerizable compound X has an aromatic ring and an ethynyl group or a vinyl group directly bonded to the aromatic ring. In the polymerizable compound X, the number of carbons derived from the aromatic ring is The total number of carbon atoms in the polymerizable compound X is preferably 15% or more and 38% or less, more preferably 18% or more and 27% or less. Thereby, the dielectric constant of the insulating film 3 can be made lower. Further, when the composition contains the polymerizable compound X as described above, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction step in the method for manufacturing a semiconductor device as described above is particularly remarkable. can do.

  In addition, since the ethynyl group or vinyl group which the polymerizable reactive group B has is a polymerizable group when the polymerizable compounds are polymerized and exhibits the same function, the polymerizable reactive group will be described below. The case where B has an ethynyl group will be described representatively.

Hereinafter, the partial structure A and the polymerizable reactive group B will be described.
[1.1] Partial structure A
The partial structure A possessed by the polymerizable compound X includes an adamantane cage structure. Thereby, the insulating film 3 formed using the film-forming composition can have a low density, and the insulating film 3 to be formed can have a low dielectric constant. In addition, since the reactivity of the polymerizable compound X having the polymerizable reactive group B as described later in detail can be made appropriate, when applying the film forming composition on the silicon-containing film 2, The viscosity of the film-forming composition is surely suitable, and unintentional variations in thickness and characteristics at each part of the insulating film 3 to be formed can be suppressed, and finally formed insulation The strength of the film 3 can be made excellent. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

Examples of the partial structure A possessed by the polymerizable compound X include adamantane, polyadamantane (eg, biadamantane, triadamantane, tetraadamantane, pentaadamantane, hexaadamantane, heptaadamantane, etc.), polyamantane (eg, diamantane, triamantane, Tetramantane, pentamantane, hexamantane, heptamantane, etc.), divalent groups such as compounds in which at least a part of hydrogen atoms constituting these compounds are substituted with alkyl groups or halogen atoms (two hydrogen atoms constituting the above compounds) A structure having two or more of these divalent groups (for example, a bi (diamantane) skeleton, a tri (diamantane) skeleton, a tetra (diamantane) skeleton, etc.) Things (Poly (Gia (Having a poly (triamantane) skeleton), such as a bi (triamantane) skeleton, a tri (triamantane) skeleton, and a tetra (triamantane) skeleton. An adamantane skeleton (or a polyadamantane skeleton) and a polyamantane skeleton, etc.) and the like. Hereinafter, a part of the example of the partial structure A is shown by a chemical structural formula, but the partial structure A is not limited to these. However, in the following formulas (A-1) to (A-7), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group, or a halogen group, and l, m, and n are each independently 1 represents an integer of 1 or more.

  The partial structure A preferably has an adamantane structure. Thereby, the dielectric constant of the insulating film 3 formed using the film forming composition can be made particularly low. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant. In addition, the reactivity of the polymerizable compound X can be made more suitable, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is more surely suitable. As a result, it is possible to more effectively suppress unintentional variations in thickness and characteristics of each part of the insulating film 3 to be formed, and to particularly improve the strength of the insulating film 3 to be finally formed. Can be.

  The adamantane structure preferably has a methyl group as a substituent. Thereby, the dielectric constant of the insulating film 3 formed using the film forming composition can be made particularly low. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant. In addition, the reactivity of the polymerizable compound X can be made more suitable, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is more surely suitable. As a result, it is possible to more effectively suppress unintentional variations in thickness and characteristics of each part of the insulating film 3 to be formed, and to particularly improve the strength of the insulating film 3 to be finally formed. Can be. Furthermore, the etching rate in the nitrogen-based etching process for patterning the insulating film 3 formed using the film-forming composition into a predetermined shape can be made relatively low.

  From the above, as the partial structure A, one having a structure represented by the following formula (2) is particularly suitable. In the following formula (2), n represents an integer of 1 or more.

  By selecting a structure having such a structure as the partial structure A, the insulating film 3 formed using the film-forming composition exhibits the above-described effects more remarkably.

  In addition, it is preferable that the partial structure A having such a structure is a structure having symmetry itself. That is, in the above formula (2), n is preferably an even number. Thereby, the reactivity of the polymerizable compound X can be made more appropriate, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is more reliably ensured. In addition, it is possible to more effectively suppress unintentional variations in the thickness and characteristics of each part of the insulating film 3 to be formed, and the strength of the finally formed insulating film 3 is particularly excellent. Can be. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

  The partial structure A may have a diamantane structure. Thereby, the dielectric constant of the insulating film 3 formed using the composition for film formation can be made low. In addition, the reactivity of the polymerizable compound X can be made more suitable, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is more surely suitable. As a result, it is possible to more effectively suppress unintentional variations in thickness and characteristics of each part of the insulating film 3 to be formed, and to particularly improve the strength of the insulating film 3 to be finally formed. Can be. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

[1.2] Polymerizable reactive group B
In addition to the partial structure A as described above, the polymerizable compound X has a polymerizable reactive group B that contributes to the polymerization reaction.

  The polymerizable reactive group B has an aromatic ring and an ethynyl group directly bonded to the aromatic ring. The polymerizable compound X may have one polymerizable reactive group B, but has two, and these have a structure in which they are symmetrically bonded around the partial structure A. preferable. Thereby, the reactivity of the polymerizable compound X can be made appropriate, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is surely suitable. As a result, it is possible to suppress unintentional variations in thickness and characteristics of each part of the insulating film 3 to be formed, and it is possible to improve the strength of the insulating film 3 to be finally formed. . In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

  As described above, the polymerizable compound X has two polymerizable reactive groups B together with the partial structure A, and furthermore, these have a specific arrangement, so that particularly excellent effects are exhibited.

  The aromatic ring constituting the polymerizable reactive group B is not particularly limited, and for example, a benzene ring, naphthalene ring, anthracene ring, naphthacene ring, phenanthrene ring, chrysene ring, pyrene ring, perylene ring, coronene ring, biphenyl ring, Hydrocarbon aromatic rings such as terphenyl ring and azulene ring, pyridine ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, indole ring, purine ring, benzofuran ring, benzothiophene ring, carbazole ring, imidazole ring, Examples thereof include heterocyclic aromatic rings such as thiazole ring, pyrazole ring, isoxazole ring, isothiazole ring, quinoline ring, and terthienyl ring. Of these, a benzene ring is preferred as the aromatic ring. Thereby, application | coating of the composition for film formation on the silicon-containing film 2 can be performed more easily. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant. Moreover, the heat resistance of the insulating film 3 to be formed, the adhesion to the silicon-containing film 2 and the like can be made particularly excellent.

  The aromatic ring constituting the polymerizable reactive group B may be bonded to the cage structure constituting the partial structure A via at least one other atom, but the cage structure constituting the partial structure A It is preferable that it is directly bonded to. Thereby, the reactivity of the polymerizable compound X can be made more suitable, and when the film-forming composition is applied on the silicon-containing film 2, the viscosity of the film-forming composition is more reliably ensured. In addition, it is possible to more effectively suppress unintentional variations in the thickness and characteristics of each part of the insulating film 3 to be formed, and the strength of the finally formed insulating film 3 is particularly excellent. Can be. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

  The polymerizable reactive group B may have one ethynyl group, but has two ethynyl groups, and two ethynyl groups are directly bonded to the aromatic ring as described above. Is preferred. Thereby, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction step in the method for manufacturing a semiconductor device as described above can be made particularly remarkable. Further, since the polymerizable reactive group B has two ethynyl groups as reaction sites, an initial reaction with respect to the polymerizable compound X easily occurs. On the other hand, when one of the two ethynyl groups of the polymerizable reactive group B reacts (polymerization reaction), the electronic state of the aromatic ring changes, and the reactivity of the other ethynyl group rapidly increases. descend. For this reason, only one ethynyl group of the two ethynyl groups of the polymerizable reactive group B can be selectively reacted under relatively mild conditions. And since the polymerizable compound X preferably has two polymerizable reactive groups B in the molecule, one of the two polymerizable reactive groups B present in the molecule of the polymerizable compound X is Only the ethynyl group can be reacted selectively. In this case, for example, a polymer (chain-like prepolymer) in which a plurality of polymerizable compounds X are polymerized one-dimensionally by a reaction shown in the following formula (3). Polymer).

（式（３）中、Ａは部分構造Ａを示し、Ａｒは重合性反応基Ｂを構成する芳香環を示す。また、ｎは、２以上の整数を表す。）

(In formula (3), A represents the partial structure A, Ar represents an aromatic ring constituting the polymerizable reactive group B, and n represents an integer of 2 or more.)

  In the case where the polymerizable reactive group B has a vinyl group instead of an ethynyl group, a polymer in which a plurality of polymerizable compounds X are polymerized one-dimensionally by a reaction shown in the following formula (3 ′) ( A chain prepolymer) is obtained.

（式（３’）中、Ａは部分構造Ａを示し、Ａｒは重合性反応基Ｂを構成する芳香環を示す。また、ｎは、２以上の整数を表す。）

(In the formula (3 ′), A represents the partial structure A, Ar represents an aromatic ring constituting the polymerizable reactive group B, and n represents an integer of 2 or more.)

  When the reaction as described above occurs, the polymerizable compound X reacts excessively during storage of the film-forming composition, and the film-forming composition becomes extremely viscous (for example, gelation). Can be reliably prevented, and when the film-forming composition is applied onto the silicon-containing film 2, the viscosity of the film-forming composition can be reliably made suitable. As a result, it is possible to reliably suppress the occurrence of unintentional variations in thickness and characteristics at each portion of the insulating film 3 to be formed.

  On the other hand, since the polymer obtained by the reaction as described above (prepolymer obtained by partial polymerization reaction) has an unreacted ethynyl group, the firing conditions as described above (silicon-containing) Under the heating conditions on the film 2, the remaining ethynyl groups can be reliably reacted, and the finally formed insulating film 3 has a three-dimensionally cross-linked structure. As a result, the formed insulating film 3 is particularly excellent in heat resistance and the like.

  As described above, when each polymerizable reactive group B constituting the polymerizable compound X has two ethynyl groups, in the polymerizable reactive group B, one ethynyl group is a meta of the other ethynyl group. It is preferable that it exists in a position. Thereby, in the state in which one ethynyl group of the two ethynyl groups of the polymerizable reactive group B has reacted (polymerization reaction), the electronic effect of the aromatic ring or the like is more significantly exhibited, and the other ethynyl group The reactivity can be reduced more effectively, the reacted site becomes an appropriate steric hindrance, and the reactivity of the other ethynyl group (unreacted ethynyl group) can be more suitably controlled. . As a result, the reactivity of the two ethynyl groups of the polymerizable reactive group B (reactivity for the first stage reaction and reactivity for the second stage reaction) is made higher. In addition, the baking process as described above can be performed under more suitable conditions (conditions that can form the insulating film 3 with excellent productivity while preventing damage to the semiconductor substrate 1 and the like). it can. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

  In addition, when the polymerizable reactive group B has two ethynyl groups, it is preferable that both of the two ethynyl groups are present at the meta position where the aromatic ring is bonded to the cage structure. Thereby, in the state in which one ethynyl group of the two ethynyl groups of the polymerizable reactive group B has reacted (polymerization reaction), the electronic effect of the aromatic ring or the like is more significantly exhibited, and the other ethynyl group The reactivity can be reduced more effectively, and the reacted site and the partial structure A described above become an appropriate steric hindrance, and the reactivity of the other ethynyl group (unreacted ethynyl group) can be reduced. It can control more suitably. As a result, the reactivity of the two ethynyl groups of the polymerizable reactive group B (reactivity for the first stage reaction and reactivity for the second stage reaction) is made higher. In addition, the baking process as described above can be performed under more suitable conditions (conditions that can form the insulating film 3 with excellent productivity while preventing damage to the semiconductor substrate 1 and the like). it can. In addition, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction process in the method for manufacturing a semiconductor device as described above can be made particularly significant.

  A polymerizable compound X that satisfies the above conditions, that is, a preferable one as the partial structure A and the polymerizable reactive group B is selected, and an aromatic ring-derived carbon in the polymerizable compound X is set to an appropriate number. Examples of the polymerizable compound X include those having a structure represented by the following formula (1) and structures represented by the following formula (5). In the following formula (1), in the following formula (5), n represents an integer of 1 to 5.

  By selecting the compound having such a structure as the polymerizable compound X, the insulating film 3 formed using the film-forming composition exhibits the above-described effects more remarkably.

  In addition, in the polymerizable compound X having the structure represented by the above formula (1), those having two polymerizable reactive groups B are exemplified, but other polymerizable compounds having one polymerizable reactive group B are exemplified. Examples of X include those having a structure represented by the following formula (1 ′). In the following formula (1 ′), n represents an integer of 1 or 2.

  The polymerizable compound X may have a partial structure other than the partial structure A and the polymerizable reactive group B.

  The polymerizable compound X as described above has two polymerizable reactive groups B, and when the polymerizable reactive group B has two ethynyl groups, for example, it can be synthesized as follows. it can.

  That is, a compound A ′ corresponding to partial structure A (a compound in which two hydrogen atoms are bonded to A as a divalent group) is reacted with bromine, and a dibromo form of A ′ (two bromo groups are bonded to partial structure A) A compound obtained by reacting a dibromo form of A ′ with dibromobenzene to obtain a bis (dibromophenyl) form of A ′ (a compound in which two dibromophenyl groups are bonded to partial structure A), and A Reacting a dibromophenyl form of 'with trimethylsilylacetylene to obtain a bis (di (trimethylsilylethynyl) phenyl) form of A' (a compound in which two di (trimethylsilylethynyl) phenyl groups are bonded to partial structure A); And a step of hydrolyzing (detrimethylsilylating) the bis (di (trimethylsilylethynyl) phenyl) form of It can be obtained that the polymerizable compound X.

  In the case where the polymerizable reactive group B has two vinyl groups instead of two ethynyl groups, the polymerizable compound X can be synthesized, for example, as follows.

  That is, after synthesizing the polymerizable compound X having the two ethynyl groups described above, although not particularly limited, Lindlar reduction using hydrogen gas, Brich reduction using sodium and liquid ammonia, diimide reduction using diimide, etc. By carrying out, the target polymeric compound X can be obtained.

  The film-forming composition may contain the polymerizable compound X alone as described above. For example, the polymerizable compound X has two polymerizable reactive groups B and / or polymerizes. When the polymerizable reactive group B has two ethynyl groups, a polymer in which the polymerizable compound X is partially polymerized (a prepolymer in which only one polymerizable reactive group B of the two polymerizable reactive groups B is polymerized or reacted) And a prepolymer obtained by polymerization reaction of only one ethynyl group of the two ethynyl groups of the polymerizable reactive group B. If the film-forming composition contains a polymer (prepolymer) in which the polymerizable compound X is partially polymerized, the viscosity of the film-forming composition is more surely suitable, and the insulating film 3 to be formed Unintentional variations in thickness and characteristics at each part can be more effectively suppressed, and the strength of the finally formed insulating film 3 can be made particularly excellent. Moreover, even if the insulating film 3 to be formed is relatively thick, it can be suitably formed. Further, if the film-forming composition contains a prepolymer of the polymerizable compound X, the amount of heat applied on the silicon-containing film 2 when forming the insulating film 3 on the silicon-containing film 2 provided on the semiconductor substrate 1 Therefore, damage to the semiconductor substrate 1 or the like due to heating can be more reliably prevented. Such a film-forming composition containing a prepolymer of the polymerizable compound X can be suitably used as an insulating film varnish.

  This step is, for example, a method by thermal polymerization in which the reaction is carried out without using a catalyst, a method by radical polymerization using a radical initiator such as benzoyl peroxide, t-butyl peroxide, azobisisobutyronitrile, Photoradical polymerization using light irradiation, etc., using palladium catalysts such as dichlorobis (triphenylphosphine) palladium (II), bis (benzonitrile) palladium (II) dichloride and tetrakis (triphenylphosphine) palladium (0) Polymerization method, polymerization method using transition metal catalyst such as copper (II) acetate, polymerization using transition metal chloride such as molybdenum chloride (V), tungsten chloride (VI) and tantalum chloride (V). The method etc. can be mentioned. Among these, since a desired polymer can be easily obtained by controlling the reaction, and impurities need not be removed by remaining a metal catalyst or the like, a method by thermal polymerization or radical polymerization using a radical initiator is desirable.

  When preparing by the thermal polymerization method, the heat treatment conditions are preferably heating temperature: 120 to 190 ° C., heating time: 3 to 11 hours, heating temperature: 140 to 180 ° C., heating time: 3 to 3 hours. More preferably, it is 9 hours. When a radical initiator is used, the heat treatment conditions are preferably heating temperature: 40 to 190 ° C., heating time: 0.5 to 11 hours, heating temperature: 60 to 180 ° C., heating time: 0. More preferably, 5 to 9 hours. Moreover, you may perform the heat processing with respect to the composition (composition containing a polymeric compound) obtained at the said process combining different conditions. For example, in the thermal polymerization, for the composition (composition containing a polymerizable compound) obtained in the above step, the first is performed under the conditions of heating temperature: 150 to 190 ° C. and heating time: 1 to 6 hours. It is also possible to appropriately select the heat treatment and the second heat treatment performed under the conditions of heating temperature: 120 to 160 ° C. and heating time: 2 to 9 hours, or further multi-stage heat treatment. Even in the case of using a radical initiator, for example, a first heat treatment performed under the conditions of heating temperature: 60 to 190 ° C., heating time: 0.5 to 6 hours, heating temperature: 40 to 160 ° C., heating time: A second heat treatment performed under a condition of 0.5 to 9 hours or a multistage heat treatment can be appropriately selected. In addition, it is preferable to perform the above heat processing in the state which melt | dissolved the composition (composition containing a polymeric compound) obtained at the said process in the solvent. In addition, the synthesis of the prepolymer by the heat treatment as described above may be performed in a solvent as a component of the film-forming composition to be prepared, and what is a component of the film-forming composition? You may perform in the solvent of a different composition. That is, after a polymerizable compound is polymerized using a predetermined solvent to obtain a prepolymer, the solvent may be replaced with a solvent as a component of the target film-forming composition. Examples of the solvent (reaction solvent) that can be used for the synthesis of a polymer (prepolymer) in which a polymerizable compound is partially polymerized include alcohol solvents such as methanol, ethanol, isopropanol, 1-butanol, and 2-butanol. ; Ketone solvents such as acetone, acetylacetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, 2-pentanone, 2-heptanone; esters such as ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, propylene glycol monomethyl ether acetate Solvents such as diisopropyl ether, dibutyl ether, diphenyl ether, tetrahydrofuran, anisole, 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, 1,4-dimethoxybenzene, etc. Solvents; aromatic and aliphatic hydrocarbon solvents such as benzene, toluene, mesitylene, ethylbenzene, diethylbenzene, propylbenzene, heptane, hexane, n-octane; chloromethane, dichloroethane, chloroform, dichloroethane, carbon tetrachloride, etc. Halide-based solvents; amide-based solvents such as N-methylpyrrolidone and the like can be mentioned, and one or more selected from these can be used in combination.

  In addition, when the film-forming composition contains a prepolymer of the polymerizable compound X, the unreacted polymerizable compound X is removed by purification (the unreacted polymerizable compound X is not included as much as possible). Is preferred. Thereby, the decrease in the oxygen content of the insulating film 3 in the oxygen content reduction step in the method for manufacturing a semiconductor device as described above can be made particularly remarkable.

  The content of the polymerizable compound X in the film-forming composition and a polymer in which the polymerizable compound X is partially polymerized (for example, only one polymerizable reactive group B out of two polymerizable reactive groups B undergoes a polymerization reaction). The sum of the prepolymer and the content of the prepolymer obtained by polymerization reaction of only one ethynyl group of the two ethynyl groups of the polymerizable reactive group B is preferably 1.0 to 30 wt%.

  In the above description, a case where a polymerizable compound having a polymerizable reactive group having an aromatic ring and an ethynyl group or a vinyl group directly bonded to the aromatic ring (polymerizable compound X) is representatively described. However, in the present invention, the polymerizable compound may be other than the polymerizable compound X as described above. For example, in the present invention, the polymerizable compound may not have an aromatic ring. Further, in the present invention, the polymerizable compound has a polymerizable reactive group as a functional group other than an ethynyl group and a vinyl group (for example, a group in which a hydrogen atom of an ethynyl group is substituted with another atom or an atomic group, a vinyl group, In which at least one of the hydrogen atoms constituting is substituted with another atom or atomic group).

  In addition, when the ethynyl group has a substituent, the trimethylsilylacetylene is substituted with an alkyl group-substituted acetylene such as propyne, butyne, pentine, or the like, or an aryl group such as phenylacetylene acetylene, naphthylacetylene, fluorenylacetylene, or the like. A polymerizable compound having a corresponding substituted ethynyl group can be obtained by performing the above steps other than detrimethylsilylation by replacing with substituted acetylene, and further with a cycloalkyl group-substituted acetylene such as cyclohexylacetylene, adamantylacetylene and the like.

  Further, when the polymerizable compound has a substituted vinyl group, the corresponding substituted vinyl group can be synthesized by performing the same reduction reaction on the substituted ethynyl group.

[2] Solvent The film-forming composition usually contains a solvent that dissolves the polymerizable compound as described above and / or a polymer obtained by partially polymerizing the polymerizable compound.

  Examples of the solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, Propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate, methyl-3-methoxy Propionate, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, tetrahydro Orchids, anisole, mesitylene and the like, can be used singly or in combination of two or more selected from these. Of these, cyclopentanone and cyclohexanone are preferable as the solvent. Examples of the solvent constituting the film forming composition include a solvent (reaction solvent) used for the synthesis of a polymerizable compound and the above-described polymer (a prepolymer obtained by partially polymerizing a polymerizable compound). It may be a thing.

  Although the content rate of the solvent in the composition for film formation is not specifically limited, It is preferable that it is 70 to 99 wt%.

[3] Other components The film-forming composition may contain components other than those described above. Examples of such components include surfactants; coupling agents such as silane coupling agents; catalysts such as radical initiators and disulfides.

  The film-forming composition may contain a naphthoquinone diazide compound as a photosensitizer. Thereby, the composition for film formation can be used suitably for formation of the surface protection film which has photosensitivity.

  In the present invention, it is preferable that the film-forming composition does not contain a pore-forming material that foams due to thermal decomposability and forms pores in the formed insulating film. Conventionally, a hole forming material has been used for the purpose of reducing the dielectric constant of the insulating film, but when such a hole forming material is used, the mechanical strength of the insulating film becomes low, The reliability of the manufactured semiconductor device is very low. On the other hand, in the present invention, the dielectric constant of the formed insulating film can be made sufficiently low without using a hole forming material. And generation | occurrence | production of the above problems can be prevented more reliably by not containing a hole formation material.

  The film forming composition as described above may be used as it is for forming the insulating film 3, but the polymerizable compound has two polymerizable reactive groups and / or polymerizable reactive groups. When has two ethynyl groups, it may be subjected to a heat treatment prior to being applied on the silicon-containing film 2. Thereby, the film-forming composition can include a polymer (prepolymer) in which the polymerizable compound is partially polymerized, and the viscosity of the film-forming composition is more surely suitable and formed. In addition, it is possible to more effectively suppress unintentional variations in thickness and characteristics at each portion of the insulating film 3 and to make the strength of the finally formed insulating film 3 particularly excellent. . Further, by applying a heat treatment to the film-forming composition prior to applying the film-forming composition onto the silicon-containing film 2, it is preferable that the insulating film 3 to be formed is relatively thick. Can be formed. Further, by applying a heat treatment to the film-forming composition prior to applying the film-forming composition onto the silicon-containing film 2 provided on the semiconductor substrate 1, the amount of heat applied on the silicon-containing film 2 is reduced. Therefore, damage to the semiconductor substrate 1 or the like due to heating can be prevented more reliably. When performing such heat treatment, the heat treatment conditions are preferably heating temperature: 120 to 190 ° C., heating time: 3 to 11 hours, heating temperature: 140 to 180 ° C., heating time: 3 to 9 hours. It is more preferable that Moreover, you may perform the above heat processing combining a different condition. For example, the 1st heat processing performed on the conditions of heating temperature: 150-190 degreeC, heating time: 1-6 hours, and the 2nd heat processing performed on the conditions of heating temperature: 120-160 degreeC and heating time: 2-9 hours And may be given.

<Insulating film, semiconductor device>
The insulating film of the present invention is composed of a material containing a polymer of a polymerizable compound, which is an organic compound having a chemical structure not containing Si, and has been subjected to plasma etching (nitrogen-based etching) treatment. The oxygen content (for example, the oxygen content when the detection depth is 5 nm from the surface) is 5.4 atomic% or less. Such an insulating film can be suitably manufactured by the method as described above.

  In addition, since the semiconductor device of the present invention is provided with the insulating film of the present invention and manufactured using the manufacturing method of the present invention as described above, for example, the signal loss and wiring delay of the semiconductor device are reduced. Small and reliable.

  As mentioned above, although this invention was demonstrated based on suitable embodiment, this invention is not limited to these.

  Hereinafter, although the present invention is explained in detail based on a concrete example and a comparative example, the present invention is not limited to this.

[1] Synthesis of polymerizable compound (Synthesis Example 1)
First, 1,3-dimethyladamantane was prepared, and carbon tetrachloride: 700 mL and bromine: 35 g (0.22 mol) were placed in a 4-neck 2000 mL flask equipped with a thermometer, a stirrer, and a reflux tube, and stirred. However, the prepared 1,3-dimethyladamantane: 32.9 g (0.2 mol) was added little by little. During the addition, the internal temperature was kept at 20-30 ° C.

After the addition was completed, the reaction was continued for another hour after the temperature did not rise.
Then, it poured into about 2000 mL of cold water, and the crude product was separated by filtration, washed with pure water, and dried.

The crude product was recrystallized from hot ethanol. The obtained recrystallized product was dried under reduced pressure to obtain 37.4 g of a product. IR analysis shows bromo group absorption at 690-515 cm ⁻¹ , and mass analysis molecular weight of 322 indicates that the product is 3,5-dimethyl-1,7-dibromoadamantane. It was.

  Next, 3,5-dimethyl-1,7-dibromoadamantane: 33.2 g (103.2 mmol) and 1,3-dibromobenzene: 1217 g (5161.6 mmol) obtained above were stirred in the flask, At 25 ° C. under dry nitrogen, 24.8 g (93.0 mmol) of aluminum (III) bromide was added in small portions. This was heated to 60 ° C. and stirred for 8 hours, and then returned to room temperature to obtain a reaction solution. The reaction solution was added to 700 ml of 5% aqueous hydrochloric acid solution and stirred. The aqueous layer was removed, and the organic layer was put into 2000 ml of acetone. The precipitate was filtered and washed with acetone: 1000 ml three times to obtain 57 g of 3,5-dimethyl-1,7-bis (3,5-dibromophenyl) adamantane. From the result of the molecular weight by mass spectrometry being 632, it was shown that the product was 3,5-dimethyl-1,7-bis (3,5-dibromophenyl) adamantane.

  Next, 3,5-dimethyl-1,7-bis (3,5-dibromophenyl) adamantane obtained above: 39.8 g (62.9 mmol), dichlorobistriphenylphosphine palladium: 3.53 g (5. 0 mmol), triphenylphosphine: 6.60 g (25.2 mmol), copper (II) iodide: 4.79 g (25.2 mmol), and triethylamine: 750 ml were added to the flask and stirred. After raising the temperature to 75 ° C., 37.1 g (377.7 mmol) of trimethylsilylacetylene was slowly added. This was stirred at 75 ° C. for 7 hours and then heated to 120 ° C. to distill off triethylamine. Then, it returned to room temperature and added dichloromethane: 1000ml to the reaction liquid, and stirred for 20 minutes. The precipitate was removed by filtration, and 5% aqueous hydrochloric acid solution (1000 ml) was added to the filtrate for liquid separation. The organic layer was washed three times with 1000 ml of water, and then the solvent of the organic layer was removed under reduced pressure. The obtained compound was dissolved in 1500 ml of hexane. Insoluble matter was removed by filtration, and hexane in the filtrate was removed under reduced pressure. Acetone: 1000 ml was added thereto, and the precipitate was washed with acetone three times to obtain 3,5-dimethyl-1,7-bis (3,5-ditrimethylsilylethynylphenyl) adamantane: 36.1 g. . From the result of the molecular weight of 701 by mass spectrometry, it was shown that the product was 3,5-dimethyl-1,7-bis (3,5-ditrimethylsilylethynylphenyl) adamantane.

  Furthermore, 3,5-dimethyl-1,7-bis (3,5-ditrimethylsilylethynylphenyl) adamantane obtained above: 32.3 g (46.1 mmol) and potassium carbonate: 1.46 g (10.6 mmol) Were stirred in a mixed solvent of tetrahydrofuran: 600 ml and methanol: 300 ml under a nitrogen atmosphere at room temperature for 4 hours. This was poured into 10% aqueous hydrochloric acid solution: 1000 ml, the precipitate was filtered, and the resulting precipitate was washed with water: 1000 ml, further washed with acetone: 1000 ml, and then dried to obtain polymerizable compound X. 3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane: 15.0 g was obtained.

  The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data indicate that the compound obtained above is 3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane.

Appearance: White solid MS (FD) (m / z): 413 (M +)
Elemental analysis: Theoretical value (/%) C; 93.16, H; 6.84, Measured value (/%) C; 93.11, H; 6.82

(Synthesis Examples 2 to 5)
A polymerizable compound X was obtained in the same manner as in Synthesis Example 1 except that tetramethylbiadamantane, hexamethyltriadamantane, octamethyltetraadamantane, and decamethylpentaadamantane were prepared instead of dimethyladamantane.

  The structural formula of the polymerizable compound X obtained in Synthesis Examples 1 to 5 is shown in the following formula (1). In the following formula (1), n represents an integer of 1 to 5, and the number of n corresponds to the number of each synthesis example.

  In addition, the external appearance of n = 2 polymerizable compound X (Synthesis example 2) in the said Formula (1), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 574 (M +)
Elemental analysis: Theoretical value (/%) C; 91.93, H; 8.07, Actual value (/%) C; 91.87, H; 8.00

  Moreover, the external appearance of the said compound (1) n = 3 polymeric compound X (synthesis example 3), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 737 (M +)
Elemental analysis: Theoretical value (/%) C; 91.25, H; 8.75, Actual value (/%) C; 91.21, H; 8.77

  The external appearance of the said compound (1) n = 4 polymeric compound X (synthesis example 4), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 899 (M +)
Elemental analysis: Theoretical value (/%) C; 90.81, H; 9.19, Measured value (/%) C; 90.75, H; 9.16

  The external appearance of the said compound (1) n = 5 polymeric compound X (Synthesis example 5), the result of mass spectrometry, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 1062 (M +)
Elemental analysis: theoretical value (/%) C; 90.51, H; 9.49, actual measurement value (/%) C; 90.49, H; 9.47

(Synthesis Example 6)
First, 4,9-dibromodiamantane was synthesized according to the synthesis method described in Journal of Organic Chemistry., 39, 2987-3003 (1974). Absorption of bromo group was observed at 690 to 515 cm ⁻¹ by IR analysis, and the result of molecular weight 346 by mass spectrometry indicated that the product was 4,9-dibromodiamantane.

  Next, in the synthesis of 3,5-dimethyl-1,7-bis (3,5-dibromophenyl) adamantane as a synthesis intermediate in Synthesis Example 1, in the synthesis of 3,5-dimethyl-1,7-dibromoadamantane, Instead, 4,9-bis (3,5-dibromophenyl) was reacted in the same manner as in Synthesis Example 1 except that 3,5.7 g (103.1 mmol) of 4,9-dibromodiamantane was used. ) Diamantane: 56 g was obtained. From the result of the molecular weight of 656 by mass spectrometry, it was shown that the product was 4,9-bis (3,5-dibromophenyl) diamantane.

  Next, in the synthesis of 3,5-dimethyl-1,7-bis (3,5-ditrimethylsilylethynylphenyl) adamantane as a synthesis intermediate in Synthesis Example 1, 3,5-dimethyl-1,7-bis is synthesized. Synthetic Example 1 except that instead of (3,5-dibromophenyl) adamantane, 4,9-bis (3,5-dibromophenyl) diamantane obtained above: 41.2 g (62.8 mmol) was used. By reacting in the same manner, 4,9-bis (3,5-ditrimethylsilylethynylphenyl) diamantane: 35.5 g was obtained. From the result of the molecular weight measured by mass spectrometry of 725, it was shown that the product was 4,9-bis (3,5-ditrimethylsilylethynylphenyl) diamantane.

  Further, in the synthesis of 3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane as the final product in Synthesis Example 1, 3,5-dimethyl-1,7-bis (3, Synthetic Example 1 except that instead of 5-ditrimethylsilylethynylphenyl) adamantane, 38.8 g (53.5 mmol) of 4,9-bis (3,5-ditrimethylsilylethynylphenyl) diamantane obtained above was used. By reacting in the same manner, 14.3 g of 4,9-bis (3,5-diethynylphenyl) diamantane as the polymerizable compound X was obtained.

  The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data indicate that the compound obtained above is 4,9-bis (3,5-diethynylphenyl) diamantane.

Appearance: White solid MS (FD) (m / z): 436 (M +)
Elemental analysis: Theoretical value (/%) C; 93.54, H; 6.46, Actual value (/%) C; 93.46, H; 6.38

(Synthesis Examples 7-9)
A polymerizable compound X was obtained in the same manner as in Synthesis Example 6 except that dibromodi (diamantane), dibromotri (diamantane), and dibromotetra (diamantane) were prepared instead of dibromodiamantane.

  The structural formula of the polymerizable compound X obtained in Synthesis Examples 6 to 9 is shown in the following formula (4). In following formula (4), n represents the integer of 1-4 and the number of n respond | corresponds to (number-5 of each synthesis example).

  In addition, the external appearance of the said Formula (4) n = 2 polymerizable compound X (Synthesis example 7), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 622 (M +)
Elemental analysis: Theoretical value (/%) C; 92.56, H; 7.44, Measured value (/%) C; 92.53, H; 7.41

  Moreover, the external appearance of the said compound (4) n = 3 polymeric compound X (synthesis example 8), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 809 (M +)
Elemental analysis: Theoretical value (/%) C; 92.03, H; 7.97, Actual value (/%) C; 92.01, H; 7.94

  The external appearance of the said compound (4) n = 4 polymeric compound X (Synthesis example 9), the result of mass spectrometry, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 995 (M +)
Elemental analysis: theoretical value (/%) C; 91.70, H; 8.30, actual value (/%) C; 91.67, H; 8.28

(Synthesis Example 10)
First, in a 4-neck 2000 mL flask equipped with a thermometer, a stirrer and a reflux tube, 3,5-dimethyl-1-bromoadamantane: 45.5 g (187.1 mmol) and 1,3-dibromobenzene: 1217 g ( 5161.6 mmol) and stirred, and at 25 ° C. under dry nitrogen, aluminum bromide (III): 24.8 g (93.0 mmol) was added in small portions. This was heated to 60 ° C. and stirred for 8 hours, and then returned to room temperature to obtain a reaction solution.

  Next, the reaction solution was added to 700 mL of 5% hydrochloric acid aqueous solution and stirred. The aqueous layer was removed, and the organic layer was poured into 2000 mL of acetone. The precipitate was filtered and washed 3 times with acetone: 1000 mL to obtain 51.4 g of 3,5-dimethyl-1- (3,5-dibromophenyl) adamantane. The result of the molecular weight of 398 by mass spectrometry indicated that the product was 3,5-dimethyl-1- (3,5-dibromophenyl) adamantane.

  Next, 3,5-dimethyl-1- (3,5-dibromophenyl) adamantane obtained above: 47.1 g (118.4 mmol), dichlorobistriphenylphosphine palladium: 6.66 g (9.5 mmol), Triphenylphosphine: 179.5 g (47.3 mmol), copper (II) iodide: 248.7 g (47.3 mmol), and triethylamine: 750 mL were added to the flask and stirred. After raising the temperature to 75 ° C., 34.9 g (355.2 mmol) of trimethylsilylacetylene was slowly added. This was stirred at 75 ° C. for 7 hours and then heated to 120 ° C. to distill off triethylamine. Then, it returned to room temperature and added dichloromethane: 1000mL to the reaction liquid, and stirred for 20 minutes. The precipitate was removed by filtration, and 5% hydrochloric acid aqueous solution: 1000 mL was added to the filtrate for liquid separation. The organic layer was washed 3 times with 1000 mL of water, and then the solvent of the organic layer was removed under reduced pressure. The obtained compound was dissolved in hexane: 1500 mL. Impurities were removed by filtration, and hexane in the filtrate was removed under reduced pressure. Acetone: 1000 mL was added thereto, and the precipitate was washed with acetone three times to obtain 37 g of 3,5-dimethyl-1- (3,5-ditrimethylsilylethynylphenyl) adamantane. The result of the molecular weight measured by mass spectrometry was 432, indicating that the product was 3,5-dimethyl-1- (3,5-ditrimethylsilylethynylphenyl) adamantane.

  Further, the 3,5-dimethyl-1- (3,5-ditrimethylsilylethynylphenyl) adamantane obtained above (36 g, 83.1 mmol) and potassium carbonate: 2.7 g (19.3 mmol) were mixed with tetrahydrofuran: 600 mL. In a mixed solvent of methanol: 300 mL, the mixture was stirred at room temperature for 4 hours under a nitrogen atmosphere. This was poured into 10% aqueous hydrochloric acid solution: 1000 mL, the precipitate was filtered, and the resulting precipitate was washed with water: 1000 mL, further washed with acetone: 1000 mL, and then dried to obtain 3 as a polymerizable compound. , 5-Dimethyl-1- (3,5-diethynylphenyl) adamantane: 19 g was obtained.

  The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data indicate that the compound obtained above is 3,5-dimethyl-1- (3,5-diethynylphenyl) adamantane.

Appearance: White solid MS (FD) (m / z): 288 (M +)
Elemental analysis: Theoretical value (/%) C; 91.61, H; 8.39, Actual value (/%) C; 91.59, H; 8.37

(Synthesis Example 11)
A polymerizable compound X was obtained in the same manner as in Synthesis Example 10 except that tetramethylbromobiadamantane was prepared instead of dimethylbromoadamantane.

  The structural formula of the polymerizable compound X obtained in Synthesis Examples 10 and 11 is shown in the following formula (1 ′). In the following formula (1 '), n represents an integer of 1 to 2, and the number of n corresponds to (Number-9 in each synthesis example).

  The appearance, mass analysis, and elemental analysis results of the polymerizable compound X (Synthesis Example 11) having the formula (1 ′) n = 2 are shown.

Appearance: White solid MS (FD) (m / z): 450 (M +)
Elemental analysis: theoretical value (/%) C; 90.61, H; 9.39, actual value (/%) C; 90.59, H; 9.36

(Synthesis Example 12)
First, 4-bromodiamantane: 50 g (187.1 mmol) and 1,3-dibromobenzene: 1217 g (5161.6 mmol) were placed in a 4-neck 2000 mL flask equipped with a thermometer, a stirrer and a reflux tube. Then, 24.8 g (93.0 mmol) of aluminum bromide (III) was added little by little at 25 ° C. under dry nitrogen. This was heated to 60 ° C. and stirred for 8 hours, and then returned to room temperature to obtain a reaction solution.

  Next, the reaction solution was added to 700 mL of 5% hydrochloric acid aqueous solution and stirred. The aqueous layer was removed, and the organic layer was poured into 2000 mL of acetone. The precipitate was filtered and washed 3 times with acetone: 1000 mL to obtain 56 g of 4- (3,5-dibromophenyl) diamantane. The result of the molecular weight of 422 by mass spectrometry showed that the product was 4- (3,5-dibromophenyl) diamantane.

  Next, 4- (3,5-dibromophenyl) diamantane obtained above: 50 g (118.4 mmol), dichlorobistriphenylphosphine palladium: 6.66 g (9.5 mmol), triphenylphosphine: 179.5 g ( 47.3 mmol), copper (II) iodide: 248.7 g (47.3 mmol), and triethylamine: 750 mL were added to the flask and stirred. After raising the temperature to 75 ° C., 34.9 g (355.2 mmol) of trimethylsilylacetylene was slowly added. This was stirred at 75 ° C. for 7 hours and then heated to 120 ° C. to distill off triethylamine. Then, it returned to room temperature and added dichloromethane: 1000mL to the reaction liquid, and stirred for 20 minutes. The precipitate was removed by filtration, and 5% hydrochloric acid aqueous solution: 1000 mL was added to the filtrate for liquid separation. The organic layer was washed 3 times with 1000 mL of water, and then the solvent of the organic layer was removed under reduced pressure. The obtained compound was dissolved in hexane: 1500 mL. Impurities were removed by filtration, and hexane in the filtrate was removed under reduced pressure. Acetone: 1000 mL was added thereto, and the precipitate was washed with acetone three times to obtain 41 g of 4- (3,5-ditrimethylsilylethynylphenyl) diamantane. From the result of the molecular weight measured by mass spectrometry being 456, it was shown that the product was 4- (3,5-ditrimethylsilylethynylphenyl) diamantane.

  Furthermore, 4- (3,5-ditrimethylsilylethynylphenyl) diamantane obtained above (40 g, 87.6 mmol) and potassium carbonate: 2.7 g (19.3 mmol) were mixed with tetrahydrofuran: 600 mL and methanol: 300 mL. The mixture was stirred for 4 hours at room temperature in a nitrogen atmosphere. This was poured into 10% aqueous hydrochloric acid solution: 1000 mL, the precipitate was filtered, and the resulting precipitate was washed with water: 1000 mL, further washed with acetone: 1000 mL, and then dried to obtain 4 as a polymerizable compound. -(3,5-diethynylphenyl) diamantane: 23 g was obtained.

  The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data indicate that the compound obtained above is 4- (3,5-diethynylphenyl) diamantane.

Appearance: White solid MS (FD) (m / z): 312 (M +)
Elemental analysis: Theoretical value (/%) C; 92.26, H; 7.74, Actual value (/%) C; 92.12, H; 7.70

(Synthesis Example 13)
A polymerizable compound X was obtained in the same manner as in Synthesis Example 12 except that bromobi (diamantane) was prepared instead of bromodiamantane.

  The structural formula of the polymerizable compound X obtained in Synthesis Examples 12 and 13 is represented by the following formula (4 ′). In the following formula (4 '), n represents an integer of 1 to 2, and the number of n corresponds to (No. 11 of each synthesis example).

  The appearance, mass analysis, and elemental analysis results of the polymerizable compound X (Synthesis Example 13) having the formula (4 ′) n = 2 are shown.

Appearance: White solid MS (FD) (m / z): 498 (M +)
Elemental analysis: Theoretical value (/%) C; 91.51, H; 8.94, Actual value (/%) C; 91.49, H; 8.46

(Synthesis Example 14)
In a 5-L eggplant flask, 14.4 g (34.9 mmol) of 3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane obtained in Synthesis Example 1 and 67.4 g (522 mmol) of quinoline were obtained. 5% palladium-calcium carbonate 0.37 g (0.174 mmol), tetrahydrofuran (1000 mL) and a stirrer were added, and stirring was started at room temperature under a hydrogen stream. When 3.35 L (139 mmol) of hydrogen was consumed, nitrogen was introduced to stop the reaction. After filtering the reaction solution, the filtrate was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography to obtain 3,5-dimethyl-1,7-bis (3,5- Divinylphenyl) adamantane 18.1 g was obtained.

  The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data indicate that the compound obtained above is 3,5-dimethyl-1,7-bis (3,5-divinylphenyl) adamantane.

Appearance: White solid MS (FD) (m / z): 420 (M +)
Elemental analysis: Theoretical value (/%) C; 91.37, H; 8.63, Actual value (/%) C; 91.35, H; 8.60

(Synthesis Examples 15-22)
The same as Synthesis Example 14 except that the polymerizable compound obtained in Synthesis Examples 2 to 9 was prepared instead of 3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane. Thus, a polymerizable compound X was obtained.

  The structural formula of the polymerizable compound X obtained in Synthesis Examples 14 to 18 is shown in the above formula (5), and the structural formula of the polymerizable compound X obtained in Synthesis Examples 19 to 22 is shown in the following formula (6). . Moreover, in Formula (5), n represents the integer of 1-5, the number of n respond | corresponds to (number-13 of each synthesis example), and in Formula (6), n represents the integer of 1-4. , N corresponds to (number -18 in each synthesis example).

  In addition, the external appearance of the said Formula (5) n = 2 polymerizable compound X (Synthesis example 15), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 582 (M +)
Elemental analysis: theoretical value (/%) C; 90.66, H; 9.34, actual measurement value (/%) C; 90.63, H; 9.31

  Moreover, the external appearance of the said compound (5) n = 3 polymeric compound X (synthesis example 16), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 745 (M +)
Elemental analysis: theoretical value (/%) C; 90.26, H; 9.74, actual measurement value (/%) C; 90.24, H; 9.70

  The external appearance of the said compound (5) n = 4 polymeric compound X (Synthesis example 17), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 907 (M +)
Elemental analysis: Theoretical value (/%) C; 90.00, H; 10.00, Actual value (/%) C; 89.96, H; 9.97

  The external appearance of the said compound (5) n = 5 polymeric compound X (Synthesis example 18), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 1069 (M +)
Elemental analysis: Theoretical value (/%) C; 89.82, H; 10.18, Actual value (/%) C; 89.80, H; 10.14

  The external appearance of the said compound (6) n = 1 polymeric compound X (Synthesis example 19), the result of mass spectrometry, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 444 (M +)
Elemental analysis: Theoretical value (/%) C; 91.84, H; 8.16, measured value (/%) C; 91.81, H; 8.13

  The external appearance of the said compound (6) n = 2 polymerizable compound X (synthesis example 20), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 630 (M +)
Elemental analysis: Theoretical value (/%) C; 91.37, H; 8.63, Actual value (/%) C; 91.32, H; 8.61

  The external appearance of the said Formula (6) n = 3 polymeric compound X (Synthesis example 21), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 817 (M +)
Elemental analysis: Theoretical value (/%) C; 91.12, H; 8.88, measured value (/%) C; 91.10, H; 8.84

  The external appearance of the said Formula (6) n = 4 polymeric compound X (Synthesis example 22), the result of a mass analysis, and an elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 1003 (M +)
Elemental analysis: Theoretical value (/%) C; 90.96, H; 9.04, measured value (/%) C; 90.93, H; 9.01

(Synthesis Example 23)
First, a reaction was carried out in the same manner as in Synthesis Example 1 except that dodecamethyl hexaadamantane was prepared instead of dimethyladamantane to obtain a product.
The appearance of the obtained product, the results of mass spectrometry and elemental analysis are shown.

Appearance: White solid MS (FD) (m / z): 1223 (M +)
Elemental analysis: Theoretical value (/%) C; 90.28, H; 9.72, Actual value (/%) C; 90.26, H; 9.70

  These data indicate that the obtained product is a compound represented by n = 6 in the formula (1).

Next, a polymerizable compound X was obtained by carrying out the same reaction as in Synthesis Example 14.
The appearance of the product, the results of mass spectrometry and elemental analysis are shown below. These data show that the compound (polymerizable compound X) obtained above is a compound represented by n = 6 in the formula (5).

Appearance: White solid MS (FD) (m / z): 1231 (M +)
Elemental analysis: theoretical value (/%) C; 89.69, H; 10.31, actual value (/%) C; 89.66, H; 10.29

(Synthesis Example 24)
According to the synthesis method described in Macromolecules, 5266 (1991), 4,9-diethynyldiamantane was synthesized.

  The appearance of the obtained product, the results of mass spectrometry and elemental analysis are shown. These data indicate that the product obtained is 4,9-diethynyldiamantane.

Appearance: White solid MS (FD) (m / z): 236 (M +)
Elemental analysis: Theoretical value (/%) C; 91.47, H; 8.53, measured value (/%) C; 91.45, H; 8.57

(Synthesis Example 25)
A product was obtained in the same manner as in Synthesis Example 12 except that bromotri (diamantane) was prepared instead of bromodiamantane.

  The appearance of the obtained product, the results of mass spectrometry and elemental analysis are shown. These data indicate that the obtained product is a compound represented by n = 3 in the formula (4 ').

Appearance: White solid MS (FD) (m / z): 684 (M +)
Elemental analysis: Theoretical value (/%) C; 91.17, H; 8.83, Actual value (/%) C; 91.14, H; 8.86

[2] Preparation of film-forming composition (Preparation Example 1)
3,5-dimethyl-1,7-bis (3,5-diethynylphenyl) adamantane: 5 g as a polymerizable compound synthesized in Synthesis Example 1 was dissolved in 45 g of 1,3-dimethoxybenzene and dried. The reaction was carried out at 170 ° C. for 3 hours under nitrogen, and the reaction solution was once cooled to room temperature. When the molecular weight was measured by GPC, the number average molecular weight was 46,000. The reaction solution was heated again and reacted at 150 ° C. for 6 hours. The reaction solution was added dropwise to a 10-fold volume of a mixed solvent of methanol / tetrahydrofuran = 3/1, and the precipitate was collected and dried. A prepolymer was obtained (yield: 56%). 2 g of the obtained prepolymer was dissolved in 18 g of cyclopentanone and filtered through a filter to obtain a film forming composition as a varnish for an organic insulating film.

(Preparation Examples 2 to 25)
As the polymerizable compound, except that each synthesized in Synthesis Examples 2 to 25 was used, a polymerization reaction was performed in the same manner as in Preparation Example 1 to obtain a prepolymer, and further using the prepolymer: 2 g, By performing the same treatment as described in Preparation Example 1, a film forming composition as a varnish for an organic insulating film was obtained.

(Preparation Example 26)
In addition, 0.7 g of polypropylene glycol diol type (Polypropylene Glycol, Diol Type, 400, manufactured by Wako Pure Chemical Industries, Ltd.) as a pore forming material is added to the composition prepared in Preparation Example 23. Thus, a film forming composition as a varnish for an organic insulating film was obtained.

  The number of carbons derived from the aromatic ring, the number of carbons derived from the polymerizable reactive group, the number of carbons derived from the partial structure, the ratio of the carbon derived from the aromatic ring, etc. Are shown in Table 1.

[3] Formation of insulating film (production of substrate with insulating film)
In the following manner, a plurality of substrates with insulating films were prepared for each example and each comparative example.

Example 1
Using the film-forming composition as the organic insulating film varnish obtained in each Preparation Example 1, an insulating film was formed as follows.

  First, a silicon wafer on which elements were formed was prepared, and a silicon-containing film (film thickness: 150 nm) made of SiCN was formed on one surface by CVD.

  Next, a film-forming composition as a varnish for an organic insulating film was applied onto the silicon-containing film using a spin coater. At this time, the rotation speed and time of the spin coater were set so that the thickness of the insulating film after the heat treatment was 100 nm.

  Next, the silicon wafer provided with the coating film as described above was placed on a hot plate at 200 ° C. for 1 minute to remove the solvent (cyclopentanone) contained in the coating film.

  Thereafter, the silicon wafer provided with the dried coating film is subjected to a heat treatment (baking treatment) for 30 minutes in a nitrogen atmosphere in an oven at 400 ° C., thereby curing the prepolymer constituting the coating film, Then, a substrate with an insulating film was obtained.

  Next, the obtained substrate with an insulating film was subjected to a nitrogen-based etching process by a reactive ion etching method using a mixed gas of nitrogen and hydrogen. In this reactive ion etching, L-201D-L manufactured by Anelva Co., Ltd., frequency: 13.56 MHz, pressure: 12.5 Pa, output: 100 W, nitrogen gas flow rate: 7.5 sccm, hydrogen gas flow rate: 2. It was performed under the conditions of 5 sccm and treatment time: 15 seconds.

Thereafter, the insulating film after the nitrogen-based etching process was subjected to oxygen content reduction treatment with H ₂ the He plasma treatment using a mixed gas of helium and hydrogen. The H ₂ He plasma treatment uses a DragonTM 2300 manufactured by ASM, frequency: 27 MHz, pressure: 200 Pa, output (RF top power): 100 W, RF bottom power: 0 W, helium gas flow rate: 5 sccm, hydrogen gas flow rate: 0 .1 sccm, temperature: 350 ° C., treatment time: 20 seconds.

(Examples 2 to 25)
As shown in Table 2, an insulating film-coated substrate was produced in the same manner as in Example 1 except that the type of film forming composition was changed and the oxygen content reduction treatment conditions were changed.

(Comparative Examples 1-4)
As shown in Table 2, a substrate with an insulating film was produced in the same manner as in Example 1 except that the type of the film-forming composition was changed and the oxygen content reduction treatment was not performed.

[4] Evaluation of Insulating Film (Substrate with Insulating Film) [4.1] Dielectric Constant For each of the examples and comparative examples, the insulating film (nitrogen-based etching treatment and oxygen content reduction treatment immediately after film formation was performed). The dielectric constant of the insulating film after the nitrogen-based etching treatment (the insulating film not subjected to the oxygen content reduction treatment) and the insulating film after the oxygen content reduction treatment were evaluated. The dielectric constant was evaluated using an automatic mercury probe CV measuring device SSM495 manufactured by Nippon SSM Co., Ltd.

[4.2] Oxygen atom concentration For each of the above Examples and Comparative Examples, the insulating film immediately after the film formation (the insulating film not subjected to the nitrogen-based etching process and the oxygen content reduction process), the insulation after the nitrogen-based etching process The O (oxygen atom) concentration of the film (insulating film not subjected to the oxygen content reduction treatment) and the insulating film after the oxygen content reduction treatment was analyzed. The analysis of O (oxygen atom) concentration was performed by X-ray photoelectron spectroscopy (XPS) using Escalab-220iXL manufactured by Thermo Fisher Scientific. The detection depth was 5 nm from the surface of the insulating film.

[4.3] Infrared spectroscopic analysis (FT-IR)
About each said Example and each comparative example, the insulating film immediately after film-forming (insulating film which has not performed nitrogen type etching processing and oxygen content rate reduction processing), and the insulating film (oxygen content rate reduction processing after nitrogen type etching processing) The insulating film that has not been applied) and the insulating film after the oxygen content reduction treatment are scraped off from the substrate and subjected to infrared spectroscopic analysis (FT-IR) by the KBr method, and the presence of a carbonyl group that is a functional group containing oxygen The presence or absence was confirmed. The infrared spectroscopic spectrum was evaluated using FT-IR8900 manufactured by Shimadzu.

[4.4] Radical concentration (spin concentration)
About each said Example and each comparative example, the insulating film (insulating film which has not performed the oxygen content rate reduction process) immediately after a nitrogen-type etching process is shaved off from a board | substrate, 3 mg is taken out from there respectively, JEOL make, electronic The radical concentration (spin concentration) was evaluated using a spin resonance apparatus JES-RE3X.

[4.5] Breakdown voltage, leakage current For each of the above examples and comparative examples, the breakdown voltage was determined using the finally obtained substrate with an insulating film (including the insulating film after the oxygen content reduction treatment). And leakage current was evaluated. The breakdown voltage and leakage current were evaluated using an automatic mercury probe CV measuring device SSM495 manufactured by Nippon SSM Co., Ltd., as with the dielectric constant.

The breakdown voltage is a voltage applied when a current of 1 × 10 ⁻² A flows, and a breakdown voltage, and the electric field strength (voltage (MV) applied when a current of 1 × 10 ⁻² A flows) is expressed as a film thickness (cm The value divided by), expressed in units of MV / cm).

The leakage current is defined as a leakage current that flows when the electric field intensity is 1 MV / cm, and the current density (A) that flows when the electric field intensity is 1 MV / cm is the mercury electrode area of the automatic mercury probe CV measuring device ( the value obtained by dividing the cm ²⁾ unit:. shown in A / cm ^2).

[4.6] Heat resistance About each said Example and each comparative example, heat resistance of an insulating film was used using the board | substrate (with an insulating film after an oxygen content rate reduction process) finally obtained. Was evaluated. The heat resistance was evaluated based on the thermal decomposition temperature. The obtained insulating film was measured using a TG / DTA measuring device (Seiko Instruments Co., Ltd., TG / DTA220) under a nitrogen gas flow of 200 mL / min. Under a temperature rising rate of 10 ° C./min. The temperature at which the weight loss reached 5% was defined as the thermal decomposition temperature.

[5] Manufacture of Semiconductor Device A plurality of semiconductor devices were manufactured for each example and each comparative example as follows.

  The surface of the insulating film of the substrate with an insulating film (substrate with an insulating film that has not been subjected to nitrogen-based etching treatment) obtained in each of the above examples and comparative examples is composed of SiO by the CVD method. A cap layer (film thickness: 30 nm) was formed.

Next, a resist film was formed on the surface of the cap layer using a spin coater.
Next, the resist film is exposed to light using a photomask so that the half pitch is 65 nm, and further developed, and the resist film is opened at a position corresponding to the position where vias (conductor posts) or wiring grooves are formed. A part (groove part) was formed.

  Next, using the patterned resist film as a mask, the cap layer made of SiO was etched (fluorine-based etching) to form an opening (groove). This step was performed by a reactive ion etching method using a gas containing carbon fluoride and nitrogen. In this reactive ion etching, L-201D-L manufactured by Anerva Co., Ltd. is used, frequency 13.56 MHz, pressure 25 Pa, output 100 W, flow rate (carbon fluoride: 4 sccm, nitrogen: 40 sccm), processing time 1 Carried out in minutes.

  Next, using the patterned cap layer as a mask, the insulating film was subjected to nitrogen etching to form an opening (groove), and the resist film remaining on the insulating film was removed by ashing. In addition, this process was performed on each Example and each comparative example on the same conditions as the nitrogen-type etching process performed by said [3], respectively.

Next, with respect to patterned insulating film was subjected to oxygen content reduction treatment with H ₂ the He plasma treatment using a mixed gas of helium and hydrogen. In addition, this process was performed on each Example and each comparative example on the same conditions as the oxygen content rate reduction process performed by said [3], respectively.

  Next, a barrier metal layer (thickness: 15 nm) made of Ta was formed on the surface side provided with the insulating film by a PVD method.

  Next, a Cu film was formed on the surface provided with the barrier metal layer by the PVD method and the electrolytic plating method. As a result, a wiring layer was formed in the groove portion of the insulating film, and a laminate in which the entire surface of the barrier metal layer (a surface parallel to the main surface of the silicon wafer) was covered with Cu was obtained.

  Next, a first polishing process and a second polishing process were performed on the stacked body by a CMP method, and a semiconductor device was obtained.

  Note that the polishing process (first polishing process and second polishing process) by the CMP method for the laminate was performed as follows.

That is, first, particles composed of a cocondensate of polymethyl methacrylate and divinylbenzene (average particle size: 40 nm): 2 wt%, hydrogen peroxide: 1 wt%, glycine: 3 wt%, benzotriazole: 0.01 wt% , Polyoxyethylene lauryl ether sulfate ammonium salt: 0.05 wt%, water: the first polishing step using the first polishing composition consisting of the balance, followed by the polishing composition, polyoxyethylene Oleyl ether sulfate ammonium salt: 0.005 wt%, oxalic acid: 0.06 wt%, colloidal silica with an average particle diameter of 20 nm: 1.25 wt%, benzotriazole: 3 wt%, hydrogen peroxide: 1 wt%, water: the balance The second polishing step was performed by changing the polishing composition 2. The first polishing step is performed until the Cu layer provided on the surface of the barrier metal layer is completely removed, and the second polishing step is performed by completely removing the barrier metal layer provided on the surface of the insulating film. I went until. In the above polishing step (first polishing step and second polishing step), a polyurethane polishing pad (IC-1000 / suba400, manufactured by Rodel) is used as a surface plate of a polishing machine, weight: 300 g / cm ² , The rotation speed of the platen was 80 rpm, the rotation speed of the wafer was 80 rpm, and the temperature of the polishing composition was 25 ° C.
A semiconductor device was manufactured as described above.

[6] Elemental analysis of sidewall (surface exposed by etching) of patterned insulating film Oxygen described above for insulating film (laminated body) having grooves obtained in the process of manufacturing the semiconductor device of [5] above The distribution state of O (oxygen atoms) on the side wall of the insulating film (surface exposed by the nitrogen-based etching process) before and after the content reduction process (whether or not oxygen atoms are unevenly distributed in the vicinity of the surface) is as follows. I investigated.

  That is, after forming a carbon protective film so as to cover the patterned insulating film, both cross sections were processed by a focused ion beam processing apparatus (hereinafter referred to as FIB). Thereafter, the element distribution state was examined by surface analysis using a transmission electron microscope (hereinafter referred to as TEM) and a transmission electron energy loss spectrometer (hereinafter referred to as EELS).

  For FIB processing, a dual beam FIB / SEM composite apparatus Nova200 Nanolab manufactured by FEI was used. For TEM observation, a FEI-made field emission transmission analysis electron microscope Tecnai G2 F20 was used. For EELS analysis, a transmission electron energy loss spectrometer GIF2001 manufactured by Gatan was used.

  Table 2 shows the types of film-forming compositions used in the examples and comparative examples, and the conditions for the oxygen content reduction treatment. Tables 3 and 4 show the results of the above evaluations.

  As is apparent from the table, excellent results were obtained with the present invention, whereas satisfactory results were not obtained with the comparative example. In addition, the chart of the infrared spectroscopy spectrum obtained as a result of [4.3] infrared spectroscopy (FT-IR) about Example 1 is shown in FIG.

  Moreover, except that the thickness of the insulating film was changed in the range of 30 nm to 20 μm, the same evaluation as described above was performed, and as a result, the same result as above was obtained.

  Moreover, when the semiconductor device manufactured in the above [5] was evaluated, it was confirmed that the present invention has small signal loss and wiring delay, and excellent reliability.

1 Semiconductor substrate 2 Silicon-containing film 3 Interlayer insulating film (insulating film)
4 Cap layer 6 Barrier metal layer 7 Wiring layer 8 Resist film 100 Semiconductor device

Claims (12)

An insulating film forming step of forming an insulating film made of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si so as to cover the semiconductor substrate on which the element is formed;
A nitrogen-based etching step of plasma etching the insulating film using a nitrogen-based gas;
A method for manufacturing a semiconductor device, comprising: an oxygen content reduction step for reducing the oxygen content of the insulating film subjected to the nitrogen-based etching step.   A resist film forming step for forming a resist film so as to cover the insulating film between the insulating film forming step and the nitrogen-based etching step; and exposure / development processing on the resist film using a photomask The method for manufacturing a semiconductor device according to claim 1, further comprising: a resist film patterning step of applying and patterning the resist film.   Between the insulating film forming step and the resist film forming step, a cap layer made of at least one material selected from the group consisting of SiO, SiN, SiC, SiCN and SiOC is formed on the surface of the insulating film. The method for manufacturing a semiconductor device according to claim 2, further comprising a cap layer forming step of forming.   4. The semiconductor device according to claim 3, further comprising a fluorine-based etching step of etching the cap layer using a fluorine-based gas with the resist film as a mask between the resist film patterning step and the nitrogen-based etching step. Manufacturing method.   5. The barrier metal layer forming step of forming a barrier metal layer for preventing diffusion of constituent components of the wiring layer on the surface side on which the insulating film is provided after the oxygen content reduction step. The manufacturing method of the semiconductor device in any one.   The wiring layer forming step of forming the wiring layer in the groove portion of the insulating film covered with the barrier metal layer and further covering the surface of the barrier metal layer with a constituent material of the wiring layer. The manufacturing method of the semiconductor device of description.   The method for manufacturing a semiconductor device according to claim 6, further comprising a polishing step of removing a portion formed of the constituent material of the wiring layer and provided outside the groove by polishing using a CMP method. The method for manufacturing a semiconductor device according to claim 1, wherein in the oxygen content reduction step, plasma treatment is performed in an atmosphere containing H ₂ and He.   9. The method of manufacturing a semiconductor device according to claim 1, wherein an O (oxygen atom) content in the vicinity of the surface of the insulating film after the oxygen content reduction step is 5.4 atomic% or less. An insulating film composed of a material containing a polymer of a polymerizable compound that is an organic compound having a chemical structure not containing Si, and subjected to plasma etching,
An insulating film having an oxygen content near the surface of 5.4 atomic% or less.   A semiconductor device manufactured using the method according to claim 1.   A semiconductor device comprising the insulating film according to claim 10.

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