JPH07183202A - Method of manufacturing x-ray mask and manufacturing device of x-ray mask using same - Google Patents

Abstract

PURPOSE:To avoid the thermal strain by a method wherein a temperature controllable solid block is brought into contact with a specific region of an X-ray transmission film for heat absorption. CONSTITUTION:A temperature controllable solid block 20 is integrated as an exclusive mask holder 11 to be portable. An X-ray mask 3 is integrated into the inside of this mask holder 11 so that the solid block 20 and a thin film 9 of the holder 11 may be left in a slightly contact state by a presser metal fitting 12 and a screw 13. When an etching pattern 7 is formed on the thin film 9 by dryetching step using a resist pattern 8 as an etching resistant mask, the thin film 9 is excessively heated but the thermal strain of the thin film 9 can be avoided by the temperature control mechanism provided on the rear surface of the thin film 9 in contact with the solid block 20 thereby enabling an extremely fine X-ray absorber pattern to be formed with high precision.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray mask (X-ray exposure mask) manufacturing method and an X-ray mask manufacturing apparatus using the same. For example, a mask surface is formed by using X-rays having a wavelength of about 2Å to 150Å. Highly accurate exposure transfer is possible in so-called X-ray lithography in which the above electronic circuit pattern is transferred onto the wafer surface to manufacture semiconductor elements such as IC and LSI.

[0002]

2. Description of the Related Art Recently, in exposure apparatuses for manufacturing semiconductor elements such as ICs and LSIs, there have been various X-ray exposure apparatuses using X-rays capable of printing with higher resolution as semiconductor elements become highly integrated. Is proposed.

Many studies have been made on the manufacturing method of the X-ray mask (X-ray exposure mask) used in the X-ray exposure apparatus using this X-ray and the manufacturing apparatus thereof.

An X-ray exposure mask (hereinafter also referred to as an "X-ray mask") generally used in an X-ray exposure apparatus is an X-ray absorber pattern having a desired pattern and a thin film supporting the X-ray absorber pattern. And a holding frame that holds the supporting film. The X-ray absorber pattern is required to have a line width of submicron or less and a positional accuracy commensurate with the line width.

Further, in many cases, the X-ray exposure requires a proximity exposure method in which the X-ray mask and the transferred object are kept to several tens of microns or less, so that the flatness of the X-ray mask is required to be highly accurate.

Since the X-ray absorber is usually formed on a support film having a thickness of several microns, precise stress control is required for each of the support film and the absorber in order to secure its positional accuracy and flatness. Come on.

[0007]

As has been conventionally done in the manufacture of X-ray masks, after forming an X-ray absorber pattern on a Si wafer, etching from the back surface of the wafer (hereinafter abbreviated as back etching) is performed. In the method of forming a window for X-rays, the internal stress of the Si wafer and the supporting film (thin film) is released during back etching, and the stress significantly deteriorates the positional accuracy of the absorber pattern on the support shaft film. Come on.

On the other hand, a method has been proposed in which a predetermined portion of a Si wafer is back-etched to form a window for X-rays, and then an absorber pattern is formed on the support shaft film.

However, if back etching is performed, Si in a predetermined portion corresponding to the mask region is lost, so that heat generated when the X-ray absorber pattern is formed by electron beam exposure (abbreviated as EB exposure) or the like. The emission decreases, the resist temperature rises, stress changes occur, the exposure conditions become unstable, and the reproducibility of patterning deteriorates. Further, even in a process such as dry etching where heat is applied, the stress of the support film changes due to the temperature rise of the support film, and it becomes difficult to secure highly accurate position accuracy and flatness.

Therefore, as a method of cooling the support film in a non-contact manner, a method of flowing helium gas on the back surface of the support film in the step of applying heat such as plasma etching is disclosed in JP-A-62-21.
It is proposed in Japanese Patent No. 9924.

However, in this method, there is always a risk that the pressure of the helium gas is applied to the supporting film having a thickness of only a few microns in a vacuum, and the supporting film is broken, and diffuses into the apparatus.
Further, as a method of cooling the support film by contact, a method of previously providing a heat dissipation material by vapor deposition of metal on the back surface of the support film at the time of patterning by EB exposure is disclosed in JP-A-61-1231.
It is proposed in Japanese Patent No. 8.

In addition to this, Japanese Patent Application Laid-Open No. 62-92437 proposes a method of contacting a liquid metal with a thin film to dissipate the heat in a process such as plasma etching where heat is applied.

However, in the former case, a heat dissipating material is added and an extra processing step is required to remove it. In addition, the latter has a problem that it is contaminated by liquid metal and is difficult to handle.

In the present invention, a step of applying heat to the X-ray transparent film, such as forming an X-ray absorber pattern on the X-ray transparent film (also referred to as a thin film or a supporting film) after back-etching the back surface of the substrate is performed. By contacting the temperature-controllable solid block with a predetermined region of the X-ray transparent film when passing through,
The X-ray transmission film absorbs heat, effectively prevents the temperature of the film from changing and the stress of the film to change to cause thermal strain.
An object of the present invention is to provide an X-ray mask manufacturing method and a manufacturing apparatus therefor capable of forming a line absorber pattern.

[0015]

According to the method of manufacturing an X-ray mask of the present invention, (1-1) after forming a thin film on the front surface of a substrate, the substrate portion in a predetermined region on the back surface of the substrate is removed by back etching. To form a frame body, and then when manufacturing the X-ray mask through the step of applying heat to the thin film, in the step of applying the heat, a region of the thin film in which the substrate portion is removed by back etching is removed. It is characterized in that a solid block whose temperature can be adjusted is brought into contact with a part.

Particularly, (1-1-1) the step of applying heat to the thin film is a step of forming an X-ray absorber pattern on the surface of the thin film.

(1-1-2) The contact surface of the solid block placed in contact with the thin film is a flat surface.

(1-1-3) The contact surface of the solid block placed in contact with the thin film is a convex curved surface.

(1-1-4) When the solid block is placed in contact with the thin film, the thin film and the solid block are opposed to each other in parallel and then brought into relatively close contact with each other.

(1-1-5) When the thin film and the solid block are brought close to and in contact with each other, a surface displacement amount of the thin film is measured, and based on the surface displacement amount, the thin film and the solid block are brought close to each other and The contact state is controlled.

(1-1-6) When the thin film and the solid block are brought close to and in contact with each other, the amount of surface displacement of the thin film is measured, and the surface formed by the thin film and the frame is based on the amount of surface displacement. The surface of the frame is positioned so that the flatness of the frame has a value within a predetermined range.

(1-1-7) When the thin film and the solid block are brought close to and in contact with each other, a surface displacement amount of the thin film is measured, and the thin film and the frame body are formed based on the surface displacement amount. The surface of the frame is positioned so that the flatness of the surface takes a value within a predetermined range, and the thin film and the solid block are brought into contact with each other by suction.

(1-1-8) The thin film is an X-ray transparent film. And so on.

(1-2) After the X-ray transparent film is provided on the front surface of the substrate, the substrate portion in a predetermined region on the back surface of the substrate is removed by back etching to form a frame, and then the X-ray transparent film is formed. When manufacturing a mask for X-rays through a step of forming an X-ray absorber pattern on the back surface, during the step of applying heat to the thermal X-ray transparent film, back etching of the back surface of the X-ray transparent film is performed. Is characterized in that a temperature-adjustable solid block is brought into contact with a part of the region where the substrate portion is removed.

In the X-ray mask manufacturing apparatus of the present invention, (2-1) a substrate having a thin film formed on the surface thereof is provided with a frame body having a predetermined area on the back side of the substrate removed by back etching. Fixing means for fixing in position, contact means for contacting a temperature-adjustable solid block to a part of the area of the back surface of the thin film from which the substrate portion has been removed by back etching, and processing for applying heat to the thin film. The X-ray mask is manufactured by utilizing the processing means for applying the temperature and the temperature adjusting means for adjusting the temperature of the solid block.

In particular, (2-1-1) the processing means for applying heat to the thin film is a means for forming an X-ray absorber pattern on the surface of the thin film.

(2-1-2) The contact surface of the solid block placed in contact with the thin film is flat.

(2-1-3) The contact surface of the solid block placed in contact with the thin film is a convex curved surface.

(2-1-4) A means for making the thin film and the solid block face each other in parallel and then bringing them into relatively close contact with each other is provided.

(2-1-5) Means for measuring the surface displacement amount of the thin film when the thin film and the solid block are brought close to and in contact with each other, and the thin film and the solid block are brought close to each other based on the surface displacement amount. And a means for controlling the contact state.

(2-1-6) Means for measuring a surface displacement amount of the thin film when the thin film and the solid block are brought close to and in contact with each other, and the thin film and the frame body based on the surface displacement amount. And a means for positioning the surface of the frame so that the flatness of the formed surface takes a value within a predetermined range.

(2-1-7) Means for measuring the amount of surface displacement of the thin film when the thin film and the solid block are brought close to and in contact with each other, and the thin film and the frame based on the amount of surface displacement. A means for positioning the surface of the frame body and a means for bringing the thin film and the solid block into contact with each other by suction so that the flatness of the surface to be formed has a value within a predetermined range. And so on.

The X-ray mask of the present invention is characterized by being manufactured according to (3-1) constituent requirements (1-1) or (1-2).

The X-ray exposure method of the present invention comprises (4-1) the requirements (3-) for the exposed member (resist).
It is characterized in that a predetermined pattern is transferred by X-ray exposure through the X-ray mask created in 1).

An X-ray exposure apparatus of the present invention comprises an X-ray source and the X-ray mask according to claim 18, and subject a member to be exposed to X-ray exposure through the X-ray mask to transfer a predetermined pattern. It is characterized by doing.

The semiconductor device of the present invention is characterized by being manufactured through a step of processing a substrate on which a pattern is transferred according to (5-1) constituent requirements (4-1).

[0037]

EXAMPLES Generally, in the process of manufacturing an X-ray mask, heat is applied to the X-ray transparent film when forming an original pattern on the X-ray transparent film (thin film) surface, drawing, or etching. , Thermal distortion occurs in the X-ray transparent film.

Therefore, in the present invention, in the step of applying heat to the X-ray transparent film, a solid block whose temperature can be adjusted is brought into contact with it to prevent the temperature from rising.

In the present invention, in order to prevent the X-ray transmission film (thin film) from being damaged by the contact at this time, the surface displacement amount of the thin film due to the contact is measured by an interferometer so that the elongation deformation of the thin film due to the contact is suppressed to a predetermined amount or less. The measuring means and the adjusting means for facing the thin film and the solid block in parallel and the moving means for bringing them into close contact with each other while facing each other are used.

As a result, the temperature of the thin film becomes almost the same as the surface of the temperature-controlled solid block. Note that this method can be sufficiently applied even in a vacuum.

Next, the manufacturing method of the X-ray mask (X-ray exposure mask) according to the present invention and the structural features thereof will be described.

The X-ray supporting film (also referred to as an X-ray transmitting film or a thin film) used in this embodiment is sufficiently transparent to X-rays and needs to be self-supporting. The thing of thickness is used. And as the material, for example, S
An inorganic material such as i, SiO ₂ , SiN, SiCN, or BN, a radiation resistant organic film such as polyimide, or a single film or a composite film of these is used.

Next, as the material of the X-ray absorber, X-rays are sufficiently absorbed, workability is good, and a thickness in the range of 0.2 to 1.0 μm is preferable. For example, Au, W, Ta. , Pt
And other heavy metals, and these compounds are used. Again X
The holding frame for holding the line supporting film is composed of a silicon wafer or the like (the thin film, the X-ray absorber and the holding frame constitute one element of the frame body).

Further, the holding frame may be provided with a reinforcing member for assisting transportation of the X-ray mask (X-ray mask structure). This reinforcing body is made of a material such as Pyrex glass, Ti, or ceramics.

In addition to the above, the X-ray mask according to the present invention is appropriately provided with a protective film for the X-ray absorber, a conductive film, an antireflection film for alignment light, and the like.

A desired pattern is formed on such an X-ray mask using a resist using an EB exposure device or the like, and the X-ray absorber is patterned through a single-layer or multi-layer resist.

At this time, etching of the multi-layer resist and X
Dry etching is used for etching the line absorber itself. In addition, for Au and the like, a deposition method such as plating is often used, and in that case as well, dry etching is used for processing the electrode such as plating.

At this time, the temperature of the thin film is controlled by using a method in which the X-ray supporting film (thin film) is brought into contact with the temperature-adjustable solid block from the surface opposite to the processed surface of the X-ray mask.

When actually contacting the thin film, an X-ray mask holding device provided with a solid block having a temperature control function is used. Further, the contact surface with the thin film has a slightly convex curvature than the flat surface so that the thin film is less likely to be subjected to bending stress. When the thin film and the solid block are brought into contact with each other by the X-ray mask holding device, the frame is first fixed, and then the thin film and the solid block are faced in parallel, and gradually brought into close contact while facing each other.

At this time, the amount of surface displacement of the thin film is measured by an interferometer to keep the amount of contact between the thin film and the solid block within a certain range. The X-ray mask holding device makes contact with the thin film by moving the solid block, but may make contact by adsorption.

When the X-ray mask holding device is used in vacuum, it is preferable to make mechanical contact so that the thin film and the solid block are kept in contact with each other even after the adsorption is released. Again X
The line mask holding device may be used also when joining the holding frame and the reinforcing body (reinforcing body). By using an X-ray mask manufacturing pattern processing device equipped with an X-ray mask holding device,
We have obtained a highly accurate X-ray mask.

In the present invention, the transferred material (exposed member) is subjected to X-ray exposure using the X-ray mask manufactured as described above, and the X-ray absorber pattern is transferred onto the transferred material.
Then, a semiconductor device is manufactured by processing and processing the transferred body.

Next, each embodiment of the X-ray mask manufacturing method of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of the essential part of a part of a manufacturing apparatus applied to the method of manufacturing an X-ray mask according to the first embodiment of the present invention.

In FIG. 1, the temperature-adjustable solid block 20 is integrated as a mask-dedicated holder 11 so that it can be carried. An X-ray mask 3 (having an X-ray absorber pattern 7, an X-ray transparent film (thin film) 9, a holding frame 10 and a resist 8 etc.) is held inside the holder 11 by a spring metal fitting 12 and a screw 13. The solid block 20 of the holder 11 and the thin film 9 are integrated in a state of lightly contacting each other. In this state, almost all the steps are performed regardless of whether the pattern drawing, exposure, dry etching at low temperature or high temperature is performed in the atmosphere or in vacuum.

In this embodiment, a state applied to dry etching is shown. Here, the fixed mask chuck 17
The holder 11 is fixed on the light source side by using the fixing bracket 15 and the bolt 16. The holder 11 does not have a temperature control function, but is made of an aluminum material having a high thermal conductivity. The temperature adjusting unit 17a is provided on the processing device side, and the holder 11 is brought into contact with the mask chuck 17 having the temperature adjusted. The temperature of the support film 9 is controlled via the solid block 20 attached to the holder 11.

In this embodiment, the holder 11, that is, the solid block 20 may be brought into contact with both the support film 9 and the holding frame 10. According to this, the temperature of the entire mask 3 is controlled via the mask chuck 17. be able to.

The contact amount is first measured by measuring the thickness of the mask 3 and is controlled to be equal to or less than the allowable value by the processing accuracy of the holder 11. When actually assembling, the film surface displacement of the thin film 9 is measured by the interferometer 16
It is performed while measuring (not shown). When the displacement of the film surface is too large, the holding frame 10 is adjusted while being tilted by three setscrews 19 to keep the surface accuracy within a predetermined range.
Reference numeral 14 is an air escape hole.

In this embodiment, the temperature can be adjusted by directly contacting the solid block 20 with the holder 11 integrated with the solid block 20 and the temperature-controlled mask chuck 17, but other than this, for example, they can be thermally coupled without direct contact. Any method that can be applied is applicable.

In this embodiment, as described above, the solid block 20 is brought into contact with the back surface of the thin film 9 (X-ray transparent film), and in this state, the resist pattern 8 is used as an etching resistant mask for X-ray etching.
The X-ray absorber pattern 7 is dry-etched to form the X-ray absorber pattern 7 on the thin film 9.

In this process, an excessive amount of heat is applied to the thin film 9. However, since the back surface of the thin film 9 is in contact with the solid block 20 having a temperature control mechanism, the surface displacement of the thin film 9 may be changed as necessary. Is measured and fed back to control the contact state of the solid block 20, so that it is possible to form an X-ray absorber pattern that is extremely fine and has excellent positional accuracy without distortion of the thin film. .

FIG. 2 shows a second embodiment of the present invention for producing an X-ray mask (X-ray copy mask) 3 using an original image 2 (X-ray mask).
It is a principal part sectional view of the manufacturing apparatus applied to the manufacturing method of the X-ray mask of the Example.

In FIG. 2, the same elements as those shown in FIG. 1 are designated by the same reference numerals.

In the present embodiment, the case where the holding portion of the X-ray mask 3 is built in the exposure apparatus side in advance is shown. The synchrotron radiation (SR) used for exposure passes through the original image 2 and exposes the resist 8. The X-ray absorber 7, the resist 8 and the X-ray transparent film (SiN) 9 generate heat by the absorbed synchrotron radiation SR. The heat is conducted to the solid block 24 having a structure in which the temperature-controlled water flows through the cooling water passage 21 to control each part within a certain temperature range.

The X-ray mask 3 is adsorbed and held on a mask chuck 23 having a groove 22 for vacuum adsorption. Reference numeral 4 is a minute displacement meter (measuring means) for measuring the amount of surface displacement of the X-ray mask 3.
That is, the amount of surface displacement due to the contact of the solid block 24 is measured by the beam 5. This measurement signal is fed back to a controller (not shown).

The controller prevents the relative displacement of the solid block 24 with respect to the stage 26 and the contact between the X-ray transmissive film 9 and the solid block 24 from being unbalanced.
Is caused by the piezo actuator 25, and the contact displacement amount of the solid block 24 of the X-ray mask 3 is controlled to be constant. In addition to the optical measurement, the measuring means 4 may use eddy current measurement, electrostatic capacitance, or the like. The actuator may be an electrostrictive element, a magnetostrictive element, or a motor and a feed screw mechanism.

The X-ray mask 3 may be attracted to the mask chuck 23 by magnetic attraction. Further, although a pair of displacement amount measuring systems is shown in the figure for easy understanding, it is preferable to have a plurality of displacement amount measuring systems so that the contact between the X-ray transmission film 9 and the solid block 24 does not make one-sided contact.

Further, in this embodiment, the contact surfaces of the X-ray transparent film 9 and the solid block 24 are appropriately roughened so that the contact surfaces do not easily stick to each other. A plurality of air escape holes 6 are provided in the solid block 24 so that the air on the contact surface can easily escape.

According to various studies in this example, SiN of 35 mm square and 2 μm in thickness was used as the X-ray transparent film,
X-ray transparent film 9 when temperature ΔT is applied to the 30 mm square part
The maximum elongation Δd of Δd = ΔT _x (9 × 10 ⁻⁸ ).
It was [m].

Therefore, the maximum allowable elongation is 0.01 μm.
When m, the allowable temperature is ± 0.11 [° C]. This is achieved by contacting the solid block 24 with SiN.
It is easily achieved with an accuracy of 0.05 ° C. Incidentally, the solid block 24 is made of Si, which is the same material as the holding frame 10. As the solid block 24, a material having a high thermal conductivity which is easy to control the temperature and does not cause heavy metal contamination is used.

On the other hand, the contact of the solid block 24 with Si
Similarly, in order to similarly reduce the amount of elongation displacement of N to 0.01 μm or less, the contact surface of the solid block 24 is formed into a spherical surface having a radius of 13.5 [m], and the contact surface is brought into contact with the pattern transfer range 27 of SiN. The surface displacement amount of SiN at this time was controlled to 10 μm or less.

When the X-ray transparent film 9 produced in the same manner was subjected to a destructive inspection by the bulge method, it was within a range having sufficient strength. In this case, since the contact surface is a spherical surface, it is easier to be parallel to SiN and air can easily escape as compared with a flat surface. Further, vibration of SiN due to contact is easily eliminated.

In this embodiment, the solid block 24 is made of SiN9.
Although they are pressed against and brought into contact with each other, the contact method is not limited to this, and other methods can be applied.

For example, the solid block 24 and the X-ray transparent film 9
And a method of adsorbing them by static electricity by approaching them to several μm, and a method of vacuum adsorbing to the solid block 24 provided with fine vacuum grooves in the same manner of approaching several μm. Since both can be made in heavy contact as compared with the method of pressing and making contact, a greater temperature control effect can be expected.

The former can also be used for exposure in vacuum. Although the contact surface of the solid block 24 is a spherical surface, it does not have to be a spherical surface. The solid block 24 may have a planar shape at a position corresponding to the pattern transfer portion (drawing portion) 27 of the X-ray transparent film 9 and a peripheral curved contact start portion with a large curved surface. In this case, since the pattern transfer portion (drawing portion) 27 is a flat surface, it is possible to deal with the problem of the depth of focus when used in light exposure.

In the present embodiment, the temperature control function is provided in the solid block 24 itself, but the present invention is not limited to this. A temperature control unit may be provided outside and the solid block 24 may be thermally coupled thereto. Further, in the case of the treatment in the atmosphere, when the X-ray permeable film 9 has temperature unevenness due to variations in contact thermal resistance or surface roughness, a slight amount of liquid or helium gas intervenes in the gap between the contact portions in order to make the heat conduction uniform. You may let me.

In addition, in the present embodiment, the solid block 24
In order to adjust the temperature of, a known cooling technique such as a Peltier element may be used in addition to flowing a liquid having a constant temperature. Further, the exposure light is not limited to X-rays, and light such as i-line of a mercury lamp, laser light such as KrF excimer laser, or the like may be used.

A reduction optical system may be arranged between the original image 2 and the X-ray mask 3 which is the object to be exposed. Further, it is more difficult to control the temperature of the X-ray mask 3 by an exposure method in a vacuum such as EB exposure and FIB, but when the present embodiment is applied, the temperature control is easy, and the X-ray mask 3 is charged. It has features such as being able to prevent ups.

FIG. 3 is a cross-sectional view of essential parts of a manufacturing apparatus applied to the method of manufacturing an X-ray mask according to the third embodiment of the present invention. The embodiment of FIG. 3 shows a case where the X-ray mask 3 is protected from a temperature rise due to the bonding when the reinforcing body 31 is bonded to the X-ray mask 3 after the pattern formation. The X-ray mask 3 after the pattern formation is composed of the X-ray absorber pattern 7, the X-ray transmissive film 9 and the holding frame 10, but it is often used in the state where the reinforcing body 31 is further provided.

In particular, when the anodic bonding method 32 is used to bond the X-ray mask 3 and the reinforcing body 31, it is necessary to heat the bonding part at several hundred degrees while applying pressure, and to apply a higher voltage. Also takes a high temperature. X-ray transmission film 9 from this heat
In order to protect the X-ray permeable film 9, the solid block 34 is brought into contact with the X-ray permeable film 9 and the solid block 34 is temperature-controlled.
The temperature rise is suppressed to about 20 ° C. Reference numeral 33 is a screw for adjusting the amount of contact between the solid block 34, the X-ray absorber pattern 7 of the X-ray mask 3 and the X-ray transparent film 9.

FIG. 4 is a sectional view showing the principal part of a manufacturing apparatus applied to the method of manufacturing an X-ray mask according to the fourth embodiment of the present invention.

In FIG. 4, the solid block 50 is replaced by the X-ray mask 3
It can be carried as a dedicated holder 41.
The X-ray mask 3 is held inside the holder 41, and the holder 41 and the X-ray transparent film 9 are integrated with each other by a spring metal fitting 42 and a screw 43 in a state of lightly contacting each other. In this state, almost all processes such as drawing and exposure, low temperature and high temperature dry etching, etc. are performed regardless of whether it is in air or in vacuum.

In this embodiment, the X-ray mask 3 is attached to the holder 41.
It shows the state of wearing. The holder 41 itself does not have a temperature control function, but is made of an aluminum material having a high thermal conductivity. Similar to the first embodiment shown in FIG. 1, the holder 41 is brought into direct contact with a temperature control section (not shown) on the apparatus side to enable temperature control.

Upon contact with the X-ray transparent film 9, first, X
The contact surfaces of the line permeable film 9 and the holder 41 are opposed to each other with a gap of 10 μm. This gap is controlled to be equal to or less than the allowable value due to the processing accuracy of the holder 41.

Next, the film surface displacement of the X-ray transparent film 9 is measured by the interferometer 36.
The X-ray transparent film 9 is suction-contacted to the holder 41 by the vacuum 47 while being measured. Since the contact is made even when the vacuum is released, the holding frame 9 is moved while being tilted by the screws 45 and the wedge-shaped tops 46 at three places to keep the surface accuracy within a predetermined range.

Finally, the vacuum 47 is released to allow the internal and external gases to communicate with each other so that the gas can be mounted on the processing apparatus in vacuum. Reference numeral 44 is a vacuum hole. 48 is a screw lock. Reference numeral 49 is a positioning screw for the mask 3.

FIG. 5 is a cross-sectional view of essential parts of a manufacturing apparatus applied to a method for manufacturing an X-ray mask according to the fifth embodiment of the present invention.

In FIG. 5, the solid block 60 is replaced by the X-ray mask 3
It is designed to be portable as a dedicated holder 52.
The holding plate 5 holds the X-ray mask 3 inside the holder 52.
3, the solid block 60 and the X-ray transparent film 9 by the screw 54
Are integrated in a state of lightly contacting.

The inner dimension 56 of the pressing plate 53 is smaller than the inner dimension 57 of the back-etched hole, and a large curvature is provided so that the X-ray transmissive film 9 is not strongly bent. By doing so, the X-ray transparent film 9 made of SiN or the like shows a very large breaking strength. In this state, in the atmosphere such as drawing and exposure
Almost all processes are performed regardless of the vacuum.

In this embodiment, an example applied to EB exposure is shown. This holder 52 itself has no temperature control function,
Made of aluminum with high thermal conductivity. The holder 52 is brought into contact with the temperature control section on the apparatus side in the same manner as the first embodiment shown in FIG. 1 to enable temperature control.

FIG. 6 is a schematic view of a main part of an exposure apparatus to which the present invention is applied for the purpose of manufacturing an X-ray mask, for example.

The figure shows a case where the pattern on the two surfaces of the original image is reduced and projected onto the transferred body 3 as an X-ray mask through the projection system 70.

In FIG. 6, 60 is an original image 2 and an X-ray mask 3.
A laser light such as He-Cd for aligning the position with, a laser light source 61, a CCD camera 62,
The mark (alignment mark) provided on the original image 2 and the X-ray mask 3 is imaged, and the mark positions of both the original image 2 and the X-ray mask 3 are detected with high accuracy by the imaging processor 63. Based on the detection result, the substrate chuck 64
X direction actuator 66, Y direction actuator 6
8 is driven to align the original image 2 and the X-ray mask 3 with high accuracy.

In this embodiment, a temperature-controlled solid block (not shown) having a flat contact surface for contacting the X-ray permeable membrane
Is attached to the substrate chuck 64, and X is applied from the back etch side.
It is in contact with the wire permeable membrane. 70 is a lens barrel of the projection optical system, 6
Reference numerals 5 and 67 are an interferometric length measuring device using a laser or the like for detecting the positions in the X direction and the Y direction, and 69 is an alignment optical unit.

In addition, in the present invention, as a light source, i-line (365 nm), KrF-excimer light (248 nm),
The present invention can be similarly applied to a stepwise-movement type reduction projection exposure apparatus or an equal-magnification mirror projection type exposure apparatus which uses ArF-excimer light (193 nm) or the like and has illumination light from these light sources. Note that the X-ray exposure apparatus is a normal X-ray exposure apparatus.
It can also be applied to the exposure process of line lithography.

Next, an example of a method of manufacturing a semiconductor device to which the present invention is applied will be described.

FIG. 7 shows a flow of manufacturing a semiconductor device (semiconductor chip such as IC or LSI, or liquid crystal panel, CCD or the like). In step 1 (circuit design), a semiconductor device circuit is designed. In step 2 (mask manufacturing), a mask having the designed circuit pattern is manufactured in the same manner as in the first embodiment.

On the other hand, in step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4
The (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by X-ray lithography using the mask and wafer prepared above.

The next step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip by using the wafer manufactured in step 4, an assembly process (dicing, bonding), a packaging process (chip encapsulation). Etc. are included. In step 6 (inspection), the semiconductor device manufactured in step 5 undergoes inspections such as an operation confirmation test and a durability test. Through these steps, the semiconductor device is completed and shipped (step 7).

FIG. 8 shows a detailed flow of the wafer process. In step 11 (oxidation), the surface of the wafer is oxidized. In step 12 (CVD), an insulating film is formed on the wafer surface.

In step 13 (electrode formation), electrodes are formed on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted in the wafer. Step 15
In (resist processing), a photosensitive agent is applied to the wafer. In step 16 (exposure), the circuit pattern of the mask is printed and exposed on the wafer by the X-ray exposure apparatus described above.

In step 17 (development), the exposed wafer is developed. In step 18 (etching), parts other than the developed resist image are removed. In step 19 (resist peeling), the resist that has become unnecessary due to etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

FIG. 9 is a schematic view of a main part when an X-ray mask manufactured by the method of the present invention is applied to an exposure apparatus for manufacturing a semiconductor element.

In FIG. 9, reference numeral 139 denotes an X-ray beam which is substantially parallel light and illuminates the surface of the X-ray mask M. W is a wafer, for example, an X-ray resist is applied on the surface.
133 is a mask frame (holding frame), and 134 is a mask membrane (X-ray transparent film), and a circuit pattern is patterned on this surface by an X-ray absorber. Reference numeral 132 is a mask support, and 136 is a wafer fixing member as a fixing means such as a wafer chuck. 137 is a Z-axis stage,
Actually, the tilt is possible. 138 is X
The axis stage 144 is a Y-axis stage.

The X-ray mask M and the wafer W alignment detection function portion (position detection device) is provided in the housings 130a and 130b.
The information on the gap between the mask M and the wafer W and the positional deviation information in the X and Y in-plane directions are obtained from this.

FIG. 9 shows two alignment detection function portions 130a and 130b.
Alignment detection function portions are further provided at two locations corresponding to each side of the corner IC circuit pattern area. An optical system and a detection system are housed in the housings 130a and 130b. Reference numerals 146a and 146b denote alignment detection light from each alignment system.

The signals obtained by these alignment detecting functional portions are processed by the processing means 140 to obtain the shift in the XY plane and the gap value. After judging this result, if it does not fall within the predetermined value, the drive systems 142, 141, 143 of the respective axis stages are moved to bring it within the predetermined mask / wafer displacement, and after that, X
The mask M is irradiated with the line exposure beam 139. Until the alignment is completed, shut off with an X-ray shielding member (not shown). In FIG. 9, the X-ray source and the X-ray illumination system are omitted.

[0108]

As described above, according to the present invention, after the back surface of the substrate is back-etched, for example, an X-ray absorber pattern is formed on the X-ray transmissive film (also referred to as a thin film or a support film). By keeping the temperature-controllable solid block in contact with a predetermined region of the X-ray transparent film during the process in which heat is applied to the transparent film, the X-ray transparent film absorbs heat and the temperature rises. It is possible to achieve an X-ray mask manufacturing method and a manufacturing apparatus therefor that effectively prevent stress from changing and causing thermal strain, and that enables highly accurate X-ray absorber pattern formation.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a first embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of an essential part of a third embodiment of the present invention.

FIG. 4 is a sectional view of a main part of a fourth embodiment of the present invention.

FIG. 5 is a sectional view of the essential parts of a fifth embodiment of the present invention.

FIG. 6 is a schematic view of a main part of an exposure apparatus for manufacturing an X-ray mask to which the present invention has been applied.

FIG. 7 is a flowchart of a method for manufacturing a semiconductor device using an X-ray mask according to the present invention.

FIG. 8 is a flowchart of a method for manufacturing a semiconductor device using an X-ray mask according to the present invention.

FIG. 9 is a schematic view of a main part of an exposure apparatus using the X-ray mask of the present invention.

[Explanation of symbols]

 2 original image 3 X-ray mask 4 measuring means 5 beam 7 X-ray absorber pattern 8 resist 9 X-ray transparent film (thin film) 10 holding frame 11 holder 17 mask chuck 20, 24, 34, 50 solid block

Claims (22)

[Claims] 1. A thin film is provided on a front surface of a substrate, a substrate portion in a predetermined region on the back surface of the substrate is removed by back etching to form a frame, and then X is formed through a step of applying heat to the thin film. In manufacturing the line mask, in the step of applying the heat, a temperature-adjustable solid block is brought into contact with a part of a region of the thin film where the substrate portion is removed by back etching. Method of manufacturing line mask. 2. The method of manufacturing an X-ray mask according to claim 1, wherein the step of applying heat to the thin film is a step of forming an X-ray absorber pattern on the surface of the thin film. 3. The method of manufacturing an X-ray mask according to claim 1, wherein a contact surface of the solid block which is placed in contact with the thin film is a flat surface. 4. The method of manufacturing an X-ray mask according to claim 1, wherein the contact surface of the solid block that is placed in contact with the thin film is a convex curved surface. 5. The X according to claim 1, wherein, when the solid block is placed in contact with the thin film, the thin film and the solid block are faced in parallel and then brought into relatively close contact with each other. Method of manufacturing line mask. 6. The surface displacement amount of the thin film is measured when the thin film and the solid block are brought close to and in contact with each other, and the proximity and contact states of the thin film and the solid block are controlled based on the surface displacement amount. The method of manufacturing an X-ray mask according to claim 5, wherein: 7. When the thin film and the solid block are brought close to and in contact with each other, the amount of surface displacement of the thin film is measured, and the flatness of the surface formed by the thin film and the frame is predetermined based on the amount of surface displacement. The method for manufacturing an X-ray mask according to claim 5, wherein the surface of the frame is positioned so that the value is within the range. 8. When the thin film and the solid block are brought close to and in contact with each other, a surface displacement amount of the thin film is measured, and a flatness of a surface formed by the thin film and the frame body is measured based on the surface displacement amount. The manufacturing of the X-ray mask according to claim 5, wherein the surface of the frame is positioned so that the value falls within a predetermined range, and the thin film and the solid block are brought into contact with each other by adsorption. Method. 9. The method of manufacturing an X-ray mask according to claim 1, wherein the thin film is an X-ray transparent film. 10. A fixing means for fixing at a predetermined position a frame body having a structure in which a substrate portion in a predetermined region on the back side of the substrate having a thin film provided on the front surface is removed by back etching, Contact means for contacting a temperature-controllable solid block with a part of the substrate-removed region of the substrate by back etching, processing means for applying heat to the thin film, and temperature control for temperature control of the solid block. An X-ray mask manufacturing apparatus, which manufactures an X-ray mask using the means. 11. The manufacturing method of an X-ray mask according to claim 10, wherein the processing means for applying heat to the thin film is a means for forming an X-ray absorber pattern on the surface of the thin film. apparatus. 12. The contact surface of the solid block disposed in contact with the thin film is a flat surface.
0 X-ray mask manufacturing equipment. 13. The apparatus for manufacturing an X-ray mask according to claim 10, wherein a contact surface of the solid block placed in contact with the thin film is a convex curved surface. 14. The apparatus for manufacturing an X-ray mask according to claim 10, further comprising means for facing the thin film and the solid block in parallel and bringing them into close contact with each other. 15. A means for measuring the amount of surface displacement of the thin film when the thin film and the solid block are brought close to and in contact with each other,
15. The X-ray mask manufacturing apparatus according to claim 14, further comprising means for controlling the proximity and contact state of the thin film and the solid block based on the surface displacement amount. 16. A means for measuring the amount of surface displacement of the thin film when the thin film and the solid block are brought close to and in contact with each other,
And a means for positioning the surface of the frame so that the flatness of the surface formed by the thin film and the frame takes a value within a predetermined range based on the amount of surface displacement. 15. The X-ray mask manufacturing apparatus according to claim 14. 17. Means for measuring the amount of surface displacement of the thin film when the thin film and the solid block are brought close to and in contact with each other,
Means for positioning the surface of the frame so that the flatness of the surface formed by the thin film and the frame takes a value within a predetermined range based on the amount of surface displacement, the thin film and the solid 15. The X-ray mask manufacturing apparatus according to claim 14, further comprising means for bringing the blocks into contact with each other by suction. 18. An X-ray mask manufactured by the method according to claim 1. 19. An X-ray exposure method comprising a step of exposing a member to be exposed through the X-ray mask according to claim 18 to transfer a predetermined pattern. 20. An X-ray source and the X-ray mask according to claim 18, wherein the member to be exposed is exposed to X-ray through the X-ray mask.
An X-ray exposure device that performs line exposure and transfers a predetermined pattern. 21. A substrate is manufactured by a process including a step of transferring a pattern on an X-ray mask surface to an exposed member formed on a substrate according to the X-ray exposure method according to claim 19 and processing the substrate. A semiconductor device characterized by. 22. After providing an X-ray transparent film on the surface of the substrate,
When manufacturing a mask for X-rays through a step of removing a substrate portion in a predetermined region on the back surface of the substrate by back etching to form a frame, and then forming an X-ray absorber pattern on the X-ray transparent film. During the step of applying heat to the thermal X-ray transparent film, a temperature-controllable solid block is brought into contact with a part of a region of the back surface of the X-ray transparent film where the substrate is removed by back etching. A method for manufacturing an X-ray mask, comprising: