JP3435643B2 - Apparatus and method for manufacturing silicon-based structure - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a processing technology for silicon-based materials and a manufacturing technology for silicon-based structures.
As used herein, the silicon-based material means single crystal silicon,
It refers to polycrystalline silicon, silicon oxide, silicon nitride, or the like. A silicon-based structure refers to a structure containing a silicon-based material during or after manufacturing. The silicon-based structure may contain a material other than the silicon-based material.

[0002]

2. Description of the Related Art With the progress of semiconductor manufacturing technology, various silicon-based material processing technologies have been developed. By using this silicon material processing technology, MOS (Metal)
It is possible to manufacture not only semiconductor elements such as Oxide Semiconductor) but also various silicon-based structures having functions such as sensors and actuators. Today, it is possible to micromachine silicon-based materials with a size of several μm or less. With this micromachining technology (micromachining technology),
It is also possible to manufacture microstructures on the order of μm.

(First Background Art) A method for manufacturing, for example, a silicon-based structure having a hollow space 320 shown in FIG. 22 by using a silicon-based material processing technique will be described with reference to FIGS. 20 to 22. .. This silicon-based structure has a beam (beam) or mass (mass) A extending above the hollow space 320. First, as shown in FIG. 20, a silicon oxide layer 308 is formed in a predetermined region on the silicon substrate 302. Next, a silicon layer 312 is formed so as to cover the silicon oxide layer 308. The sample shown in FIG. 20 obtained through the above steps is housed in the etching reaction chamber of the dry etching apparatus. With this device,
A gas for etching silicon is supplied to the etching reaction chamber to locally dry-etch the silicon layer 312 as shown in FIG. As a result, an etching hole 318 reaching the silicon oxide layer 308 is formed. As a result, part of the silicon oxide layer 308 is exposed. The sample shown in FIG. 21 in which the etching hole 318 is formed is housed in the etching container of the wet etching apparatus this time and immersed in the etching solution. This etching solution is, for example, a solution (dilute HF) diluted with hydrofluoric acid. The hydrogen fluoride solution etches silicon oxide and barely etches silicon. As a result, as shown in FIG. 22, the silicon oxide layer 308 is removed by wet etching. The silicon oxide layer 308 is a layer for creating the hollow space 320 by finally removing it.
This layer is commonly referred to as the "sacrificial layer". As a result, a hollow silicon structure having the hollow space 320 is manufactured.

This structure is used, for example, as an acceleration sensor. When used as an acceleration sensor,
A portion A of the silicon layer 312 is used as a beam or mass that is displaced when acceleration acts. For example, when acceleration in the direction perpendicular to the substrate surface of the silicon substrate 302 acts, the mass A is displaced in the direction perpendicular to the substrate surface. The applied acceleration can be detected by detecting the displacement of the mass A as a change in the capacitance between the electrode pair (not shown). Alternatively, the beam A bends when acceleration in a direction perpendicular to the substrate surface of the silicon substrate 302 acts. The acting acceleration can be detected by detecting the deflection of the beam A as a resistance change of the piezoresistor not shown. It is also possible to detect the acceleration in the direction parallel to the substrate surface of the silicon substrate 302.

(Second Background Art) A method of manufacturing a silicon-based structure having a hollow space 420 shown in FIG. 26, for example, by using a silicon-based material processing technique will be described with reference to FIGS. 23 to 26. . This silicon-based structure has a diaphragm B located above the hollow space 420. First, as shown in FIG. 23, a lower electrode 404 is formed by locally implanting impurities into the single crystal silicon substrate 402. The surface of the silicon substrate 402 is nitrided to form a lower silicon nitride layer 410. A polycrystalline silicon layer 408 is formed on a predetermined region of the lower silicon nitride layer 410. In this example, the polycrystalline silicon layer 40
8 is a sacrifice layer. An upper first silicon nitride layer 412 is formed so as to cover the polycrystalline silicon layer 408. An upper electrode 406 is formed on a predetermined region of the upper first silicon nitride layer 412. The upper electrode 406 is formed of polycrystalline silicon or the like. A second upper portion is formed so as to cover the upper electrode 406.
A silicon nitride layer 414 is formed. The upper silicon nitride layers 412 and 414 are etched in the portion where the upper electrode 406 does not exist to form an etching hole 418 reaching the polycrystalline silicon layer 408. As a result, a part of the polycrystalline silicon layer 408 is exposed. As a result, the exposed portion of the polycrystalline silicon layer 408 is oxidized to form a natural oxide film (silicon oxide) 419.

The sample obtained through the above steps is
It is placed in an etching container of a silicon oxide wet etching apparatus and immersed in an etching solution. This etching solution is a solution (dilute HF) diluted with the above-mentioned hydrofluoric acid. The hydrogen fluoride solution etches silicon oxide and barely etches silicon nitride. As a result, as shown in FIG. 24, the natural oxide film 419 is removed by wet etching. Next, the natural oxide film 419
The sample from which is removed is housed in an etching reaction chamber of a silicon dry etching apparatus. In this apparatus, a gas that etches silicon and barely etches silicon nitride is supplied to the etching reaction chamber to dry-etch the sacrificial layer polycrystalline silicon layer 408. As a result, the hollow space 420 is formed.

Thereafter, as shown in FIG. 25, the upper electrode 4
06 and the lower electrode 404 on the contact holes 422a, 42
2b is formed. After that, an aluminum layer 416 to be a wiring layer is formed over the surface of the sample. Then, FIG.
As shown in FIG. 7, the aluminum layer 416 is patterned to form a wiring layer 416a in contact with the upper electrode 406 and a wiring layer 416b in contact with the lower electrode 404. After that, the sealing layer 424 is formed to seal the etching hole 418.
As a result, a hollow silicon-based structure having the hollow space 420 is manufactured. This structure functions as a pressure sensor.

In this structure, the upper silicon nitride layer 41 is formed.
2, 414, the upper electrode 406, and the predetermined portion B of the sealing layer 424 function as a diaphragm. The hollow space 420 is a sealed space and functions as a pressure reference chamber. In this structure, the diaphragm B bends according to the difference between the pressure applied to the diaphragm B and the reference pressure. When the diaphragm B bends, the distance between the upper electrode 406 and the lower electrode 404 changes. When the distance between the electrodes 406 and 404 changes, the capacitance between the electrodes 406 and 404 changes. The amount of pressure acting on the diaphragm B can be detected by detecting the amount of change in the capacitance.

[0009]

In any of the background arts, wet etching is performed to remove silicon oxide. However, if wet etching is performed, then it is necessary to perform a step of cleaning the etching solution attached to the sample and a step of drying the sample after the cleaning. Therefore, there is a problem that the manufacturing process of the structure becomes complicated.

Further, if wet etching is performed, the layers surrounding the hollow space of the hollow structure will stick to each other due to the surface tension of the liquid in the subsequent washing and drying steps.
A so-called sticking phenomenon may occur. When the sticking phenomenon occurs, the structure hardly functions as a sensor or an actuator. That is, the sticking phenomenon causes defective products and reduces yield. Taking the first background art as an example, in the structure shown in FIG. 22, when the silicon layer 312 functioning as the mass and the beam A is attached to the silicon substrate 302, the displacement amount of the mass A due to the acting acceleration or the beam A of the beam A. The amount of deflection is significantly reduced. As a result, this structure hardly functions as an acceleration sensor. Second
Taking the background art as an example, if the upper first silicon nitride layer 412 functioning as the diaphragm B shown in FIG. 26 is stuck to the lower silicon nitride layer 410, the amount of deflection of the diaphragm B due to the acting pressure is significantly reduced. As a result, this structure has almost no function as a pressure sensor.

There is an increasing demand for higher sensitivity and higher accuracy of sensors and actuators. To meet this demand,
The rigidity of the structure is lower and the geometry of the structure tends to be smaller. The lower the rigidity of the structure or the smaller geometry of the structure, the greater the likelihood of sticking phenomena due to wet etching. As described above, in recent years, defective products are more likely to occur due to wet etching.

Conversely, in order to prevent defective products from being generated, it is unavoidable to increase the rigidity of the structure and increase the shape and size of the structure. As a result, realization of a structure that functions as a highly sensitive or highly accurate sensor or actuator is hindered. Further, according to the manufacturing process of the second background art, as shown in FIG. 25, when the aluminum layer 416 is formed, the aluminum 416 enters the space 420 from the etching hole 418. As a result,
As shown in FIG.
In some cases, c may remain in the space 420 without being removed even after patterning. If the aluminum 416c remains in the space 420, the deflection of the diaphragm B is obstructed when pressure is applied to the diaphragm B. That is, a structure that hardly functions as a pressure sensor is manufactured, and a defective product is generated.

The native oxide film 419 and the silicon layer 4 shown in FIG.
If the aluminum layer 416 can be formed before etching 08, such a problem does not occur. However, the hydrogen fluoride solution that etches the native oxide film 419 etches the aluminum 416. Therefore, the second
In the background art, after etching the native oxide film 419 and the silicon layer 408 of FIG. 23, the aluminum layer 4 of FIG.
There is no choice but to form 16. The same problem may occur in the silicon-based structure of the first background art. Further, not only the occurrence of the sticking phenomenon at the time of manufacturing the silicon-based structure but also the reduction of the occurrence of the sticking phenomenon at the time of use is an important issue. If the occurrence of the sticking phenomenon during use can be reduced, the occurrence of defective products during use of the silicon-based structure can be reduced.

The problems in the case of wet etching silicon oxide with a hydrogen fluoride solution have been described above. On the other hand, in recent years, an apparatus capable of dry etching silicon oxide with hydrogen fluoride gas has also appeared. A technique related to this is disclosed in Japanese Patent Laid-Open No. 8-1160.
70 and Japanese Patent Application Laid-Open No. 4-96222. However, even when this apparatus is used, it is necessary to perform a troublesome work of transferring the sample between the etching reaction chamber of the silicon dry etching apparatus and the etching reaction chamber of the silicon oxide dry etching apparatus. This work complicates the manufacturing process. Further, when transferring the sample, the sample is exposed to the outside air. This causes a defective product during manufacturing of the silicon-based structure or a defective product during use. In particular, when the sample is transferred to perform the dry etching of silicon after performing the dry etching of the natural oxide film formed on the surface of silicon, the sample is exposed to the outside air, There is a risk that a natural oxide film will be formed again on the surface.

As described above, when the etching of silicon and the etching of silicon oxide are performed by using different dry etching apparatuses, the above-mentioned problems and the problem of high cost occur. Therefore, when manufacturing a silicon-based structure, as described in the first and second background art, silicon is etched by a silicon dry etching apparatus, and silicon oxide is etched by a widely used oxidation method. It is practically common to use a wet etching apparatus for silicon.

A first object of the present invention is to simplify the manufacturing process of a silicon-based structure. A second object of the present invention is to reduce the occurrence of defective products during manufacturing of silicon-based structures or the occurrence of defective products during use. A third object of the present invention is to realize a silicon-based structure that functions as a highly sensitive or highly accurate sensor or actuator. The present invention has been made to solve at least one of the above problems.

[0017]

[Means, Actions and Effects for Solving the Problems] Both the above-described silicon dry etching apparatus and silicon oxide dry etching apparatus were manufactured in consideration of processing of structures such as sensors and actuators. However, there is a background that it is made in consideration of processing of semiconductor elements such as MOS. In the processing of semiconductor elements such as MOS, there are many cases where the material that needs to be etched is only silicon or only silicon oxide. Even when both silicon and silicon oxide must be etched, one of the materials (silicon or silicon oxide) is etched and then processed (such as crystal growth or film forming), and then the other material (oxidized). Silicon or silicon). The above-described silicon dry etching apparatus and silicon oxide dry etching apparatus are made assuming these cases. MO
In the processing of a semiconductor element such as S, it is rare that one material (silicon or silicon oxide) is etched and then the other material (silicon oxide or silicon) is subsequently etched.

Under such circumstances, the inventors of the present invention have conducted earnest research to realize a technique suitable for manufacturing a silicon-based structure, and as a result, dry etching of silicon and dry etching of silicon oxide are performed. The inventors have found the idea that the above-mentioned problems relating to the silicon-based structure can be effectively solved by performing them in the same etching reaction chamber.

In the silicon-based material processing apparatus or silicon-based structure manufacturing apparatus embodying the present invention, the manufacture of a silicon-based structure that functions as a sensor, an actuator or the like is initially in mind. It is a novel device. The present invention is also embodied in a method for manufacturing a silicon-based structure.

Hereinafter, first to eighth aspects embodying the present invention and more preferable embodiments of these aspects will be described. A first aspect embodying the present invention is a silicon-based material processing apparatus. This apparatus includes a first gas supply unit, a second gas supply unit, an etching reaction chamber, a selective communication unit, and a gas discharge unit. The first gas is a gas that etches silicon. The second gas is a gas that etches silicon oxide and hardly etches silicon. The selective communication means selectively communicates the etching reaction chamber with either the first gas supply unit or the second gas supply unit. The gas discharging means discharges the gas in the etching reaction chamber.

According to this aspect, the first gas can be supplied to the etching reaction chamber by connecting the first gas supply section to the etching reaction chamber by the selective communication means. By supplying the first gas to the etching reaction chamber, at least a part of silicon can be removed by dry etching. The gas discharging means can discharge the first gas in the etching reaction chamber. The second gas can be supplied to the etching reaction chamber by connecting the second gas supply unit to the etching reaction chamber by the selective communication means. By supplying the second gas to the etching reaction chamber, when silicon remains, at least a part of the silicon oxide can be removed by dry etching while leaving the silicon. Of course, the first gas may be supplied after the second gas is supplied.

According to this aspect, no wet etching is required to remove the silicon oxide. Therefore, it is not necessary to perform the step of cleaning the etching liquid attached to the sample and the step of drying the sample after the cleaning.
Therefore, the manufacturing process of the silicon-based structure can be simplified. In addition, since wet etching is not required to remove silicon oxide, the possibility of sticking phenomenon during manufacturing can be extremely reduced. Therefore, it is possible to reduce the occurrence of defective products during manufacturing. In other words, the rigidity of the structure can be reduced and the shape and size of the structure can be reduced as compared with the case where wet etching is performed.
Therefore, it is possible to realize a structure that functions as a highly sensitive or highly accurate sensor or actuator. Further, since silicon and silicon oxide can be dry-etched in the same etching reaction chamber, the laborious work of transferring the sample between the etching reaction chamber of the silicon dry etching device and the etching reaction chamber of the silicon oxide dry etching device is required. It becomes unnecessary. Therefore, the manufacturing process can be simplified. Since it is not necessary to transfer the sample between the etching reaction chambers, the sample is not exposed to the outside air during that time. In particular, it is possible to prevent the natural oxide film from being formed again on the surface of the sample after etching the natural oxide film formed on the surface of silicon. It is possible to reduce the occurrence of defective products during manufacturing of the silicon-based structure or the occurrence of defective products during use. The above effects can be similarly obtained in the second to eighth aspects described below.

The silicon-based material processing apparatus of the second aspect is similar to the first aspect, in that the first gas supply section, the second gas supply section, the etching reaction chamber, the selective communication means, and the gas exhaustion. Equipped with means. The first gas is a gas that etches silicon oxide and barely etches silicon nitride. The second gas is a gas that etches silicon and hardly etches silicon nitride.

According to this aspect, by supplying the first gas to the etching reaction chamber, at least a part of the silicon oxide is removed by dry etching while preventing the silicon nitride from being etched when the silicon nitride is present. it can. After discharging the first gas from the etching reaction chamber, by supplying the second gas to the etching reaction chamber, at least a part of the silicon is removed while not etching the silicon nitride when the silicon nitride is present. It can be removed by dry etching. Second
Of course, the first gas may be supplied after the gas is supplied.

The third aspect is an apparatus for manufacturing a silicon-based structure. This apparatus manufactures a hollow silicon-based structure by processing a sample in which a second silicon-based material is formed on a first silicon-based material and the second silicon-based material is covered with a third silicon-based material. It is a device. This device is
Similar to the above aspect, the first gas supply unit, the second gas supply unit, the etching reaction chamber, the selective communication unit, and the gas discharge unit are provided. The first gas is a gas that exposes a part of the second silicon-based material. The second gas is a gas that etches the second silicon-based material and hardly etches the first and third silicon-based materials.

Here, the first silicon material to the third silicon material are any of silicon, silicon oxide and silicon nitride. The first silicon-based material and the third silicon-based material may be the same. The first silicon material and the second silicon material are different, and the second silicon material and the third silicon material are also different.

According to this aspect, by supplying the first gas to the etching reaction chamber and performing dry etching, a part of the second silicon-based material can be exposed. After the first gas is discharged from the etching reaction chamber, the second gas is supplied to the etching reaction chamber, so that the first and third gases are discharged.
The second silicon-based material can be removed by dry etching while not etching the silicon-based material.
As a result, a silicon-based structure having a hollow space formed by etching the second silicon-based material is manufactured.

A fourth aspect is an apparatus for manufacturing a silicon-based structure, which is a more specific version of the third aspect. This device
This is an apparatus for manufacturing a hollow silicon-based structure by processing a sample in which a silicon oxide layer is formed on a silicon substrate and the silicon oxide layer is covered with the silicon layer. This device is provided with a first gas supply unit, a second gas supply unit, an etching reaction chamber, a selective communication unit, and a gas discharge unit, as in the first aspect. The first gas is a gas that etches silicon. The second gas is a gas that etches silicon oxide and hardly etches silicon.

According to this aspect, a part of the silicon oxide layer can be exposed by locally supplying the first gas to the etching reaction chamber to dry-etch the silicon layer. By discharging the first gas from the etching reaction chamber and then supplying the second gas to the etching reaction chamber, the silicon oxide layer can be removed by dry etching while preventing the silicon substrate and the silicon layer from being etched. As a result, a silicon-based structure having a hollow space formed by etching the silicon oxide layer is manufactured.

The fifth aspect is an apparatus for manufacturing a silicon-based structure, which is a more specific form of the third aspect. This device
A silicon layer is formed on the lower silicon nitride layer, the silicon layer is covered with an upper silicon nitride layer, holes are formed in the upper silicon nitride layer, and the surface of the silicon layer located corresponding to the holes is oxidized. It is an apparatus for manufacturing a hollow silicon-based structure by processing a sample on which silicon is formed. This device is provided with a first gas supply unit, a second gas supply unit, an etching reaction chamber, a selective communication unit, and a gas discharge unit, as in the first aspect. The first gas is a gas that etches silicon oxide and barely etches silicon nitride. The second gas is a gas that etches silicon and hardly etches silicon nitride.

According to this aspect, a part of the silicon layer can be exposed by supplying the first gas to the etching reaction chamber and dry etching the silicon oxide formed on the surface of the silicon layer. After discharging the first gas from the etching reaction chamber, a second gas is discharged into the etching reaction chamber.
By supplying the gas, the silicon layer can be removed by dry etching while preventing the lower silicon nitride layer and the upper silicon nitride layer from being etched. As a result, a silicon-based structure having a hollow space formed by etching the silicon layer is manufactured.

In the first to fifth aspects, it is preferable that the first gas and the second gas are gases that hardly etch the aluminum material. Examples of aluminum-based materials include aluminum and Al.
Aluminum alloys such as -Si and Al-SI-Cu are mentioned. If the first gas and the second gas hardly etch the aluminum-based material, these gases can form the aluminum-based material before etching silicon and silicon oxide. Therefore, it is possible to prevent the aluminum-based material from entering the hollow space removed by dry etching. Therefore, it is possible to reduce the occurrence of defective products during manufacturing or the occurrence of defective products during use.

In the first to fifth aspects, it is preferable that the gas supply section has a storage section for a solid or liquid which is a raw material of gas. Furthermore, it is preferable to provide a gas conversion means for converting the solid or liquid into a gas. According to this aspect, the gas can be stored in a solid or liquid state that is easier to handle than gas, and can be converted into gas and supplied when it is necessary to supply gas to the etching reaction chamber. Therefore, the convenience of the device can be improved.

The gas supply also preferably has a reservoir of gas converted from solid or liquid. According to this aspect, the gas converted from the solid or the liquid can be stored, so that it is possible to sufficiently deal with the case where the dry etching with a large amount of gas is necessary.

More specifically, the gas supply unit is a solid xenon difluoride (XeF ₂ ) or bromine trifluoride (Br).
It is preferable to have a container containing F ₃ ). The xenon difluoride gas or the bromine trifluoride gas obtained by gasifying the raw materials contained in these containers has the property of etching silicon and hardly etching silicon oxide, silicon nitride, and aluminum-based materials. Therefore, a gasified material of these containers is a gas suitable as the first gas in the fourth aspect or the second gas in the fifth aspect.

Alternatively, the gas supply section may use hydrogen fluoride (H
F) a container containing the solution and methyl alcohol (CH ₃
It is preferable to have a container containing an (OH) solution or water (H ₂ O). A mixed gas of hydrogen fluoride gasified from raw materials and methyl alcohol or water contained in these containers has a property of etching silicon oxide and hardly etching silicon, silicon nitride, and aluminum-based materials. Therefore, a gasified material of these containers is a gas suitable as the second gas in the fourth aspect or the first gas in the fifth aspect.

When the liquid in the liquid containing portion is converted into gas and supplied to the etching reaction chamber, it is preferable to further include means for suppressing clogging of the liquid between the liquid containing portion and the etching reaction chamber. According to this aspect,
Even when the liquid in the liquid containing portion is converted into gas, the liquid can be prevented from being clogged even if the liquid bumps into the pipe or the like between the liquid containing portion and the etching reaction chamber.

The gas converting means is preferably a depressurizing means for depressurizing the solid or liquid containing portion. Further, it is preferable that the depressurizing means and the solid or liquid containing portion are connected via an etching reaction chamber. According to this aspect,
While converting the solid or liquid in the solid or liquid storage portion into a gas, the converted gas can be quickly introduced into the etching reaction chamber.

In the first to fifth aspects, it is preferable that the etching reaction chamber is provided with a means for preventing a linear gas flow from the gas supply port to the gas discharge port. Providing such blocking means can improve the uniformity of the gas flow in the etching reaction chamber.

In the first to fifth aspects, it is preferable that the gas discharging means has a high speed discharging means and a low speed discharging means. By providing these discharge means, it is possible to discharge gas efficiently, for example, discharging at low speed normally and discharging at high speed only when necessary.

In each of the first to fifth aspects, it is preferable to further include an etching end detecting means for detecting the end of etching of the sample. By using this detecting means, it is possible to prevent a situation in which etching is performed more than necessary, or conversely etching is insufficient, even when the sample size varies.

In the first to fifth aspects, a container for containing the organosilicon compound, a container for containing water, and a gas conversion means for converting the organosilicon compound contained in these containers and water into a gas. It is preferable to further include a coating chamber connected to these containers. This aspect is
This is a useful technique for suppressing the occurrence of sticking phenomenon when using a silicon-based structure. According to this aspect,
The surface of the silicon-based structure formed by the first to fifth aspects can be coated with a water-repellent film. Therefore,
The water repellency of the silicon-based structure can be improved.
Therefore, for example, even when the structure is used in an environment where dew condensation is likely to occur, it is possible to prevent the liquid from adhering to the structure and causing the sticking phenomenon due to the surface tension of the liquid. Therefore, it is possible to reduce the occurrence of defective products during use.

Further, the following connecting portion, opening and closing means,
It is preferable to provide a sample transport means. The connection part connects the etching reaction chamber and the coating chamber by blocking them from the outside air. The opening / closing means can switch between the etching reaction chamber and the coating chamber into an open state and a closed state. The sample transfer means can transfer the sample between the etching reaction chamber and the coating chamber. Alternatively, it is preferable to include the following preparatory chamber, connecting portion, opening / closing means, and sample transfer means. The connection part connects the etching reaction chamber and the preparatory chamber and the preparatory chamber and the coating chamber by blocking them from the outside air. The opening / closing means can switch between the etching reaction chamber and the preliminary chamber and between the preliminary chamber and the coating chamber into an open state and a closed state. The sample transfer means can transfer the sample between the etching reaction chamber and the preliminary chamber and between the preliminary chamber and the coating chamber. According to these aspects, the structure after dry etching is completed in the etching reaction chamber can be transported to the coating chamber without being exposed to the outside air. Therefore, the oxidation of the structure can be prevented. Furthermore, if a preliminary chamber is provided, it becomes easier to transfer the structure between the etching reaction chamber and the coating chamber.

The present invention is also embodied in a method of making a useful silicon-based structure. A method of manufacturing a silicon-based structure according to a sixth aspect of the present invention has the following steps. A second silicon-based material is formed on the first silicon-based material. A third silicon material is formed so as to cover the second silicon material. The sample obtained through the above steps is placed in the etching reaction chamber. A first gas is supplied to the etching reaction chamber to locally perform dry etching to expose a part of the second silicon-based material. The first gas is discharged from the etching reaction chamber. A second silicon-based material is etched into the etching reaction chamber to remove the first and third silicon materials.
A second gas that does not etch the silicon-based material is supplied to dry-etch the second silicon-based material. here,
The first silicon material to the third silicon material are any of silicon, silicon oxide, and silicon nitride. The first silicon material and the third silicon material may be the same, while the first silicon material and the second silicon material are different, and the second silicon material and the third silicon material are also different. There is.

The seventh aspect is a method of manufacturing a silicon-based structure, which is a more specific form of the sixth aspect. This manufacturing method has the following steps. A silicon oxide layer is formed on a silicon substrate. A silicon layer is formed so as to cover the silicon oxide layer. The sample obtained through the above steps is placed in the etching reaction chamber. A first gas for etching silicon is supplied to the etching reaction chamber,
The silicon layer is locally dry-etched to expose a part of the silicon oxide layer. The first gas is discharged from the etching reaction chamber. A second gas that etches silicon oxide and hardly etches silicon is supplied to the etching reaction chamber to dry-etch the silicon oxide layer.

The eighth aspect is a method for manufacturing a silicon-based structure, which is a more specific form of the sixth aspect. This manufacturing method has the following steps. A silicon layer is formed on the lower silicon nitride layer. An upper silicon nitride layer is formed so as to cover the silicon layer. A hole reaching the silicon layer is formed in the upper silicon nitride layer. The sample obtained through the above steps is placed in the etching reaction chamber. A first gas that etches silicon oxide and hardly etches silicon nitride is supplied to the etching reaction chamber to dry-etch the silicon oxide formed on a portion of the surface of the silicon layer corresponding to the hole of the upper silicon nitride layer. Then, a part of the silicon layer is exposed. The first gas is discharged from the etching reaction chamber. A second gas that etches silicon and hardly etches silicon nitride is supplied to the etching reaction chamber to dry-etch the silicon layer.

In the sixth to eighth aspects, the first gas and the second gas are selected from gases that hardly etch aluminum-based materials, aluminum exposed on the surface of the sample is formed, and then the sample is etched in the reaction chamber. It is preferable to store in.

It is preferable to have a step of exposing the structure that has undergone the steps of any of the sixth to eighth aspects to a mixed gas of water vapor and an organosilicon compound.

In the present specification, a gas that etches one material (for example, silicon) and hardly etches the other material (for example, silicon oxide) includes, for example, the etching rate of one material and the etching rate of the other material. A gas having a ratio (etching selection ratio) of 15 or more is included. The etching selection ratio is preferably 20 or more, more preferably 30 or more.
The other material mentioned here includes the above-mentioned aluminum-based material. The gas that hardly etches the other material naturally includes a gas that does not etch the other material at all.

[0050]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) FIG. 1 shows the configuration of a silicon-based structure manufacturing apparatus (hereinafter referred to as "structure manufacturing apparatus") of the first embodiment. This apparatus can be used as a processing apparatus for silicon-based materials because it can be used for processing all silicon-based materials. Of manufacturing equipment.
The structure manufacturing apparatus according to the first embodiment includes a xenon difluoride container 20, a sublimation gas storage container 21, and a hydrogen fluoride container 30.
And the methyl alcohol container 31 and the etching reaction chamber 1
0, a dry pump 42, an abatement device 49, a turbo molecular pump 40, a rotary pump 41, and a control unit 50.
It has 2 etc.

The xenon difluoride container 20 contains solid xenon difluoride (XeF ₂ ). Xenon difluoride is a solid at room temperature and pressure. In the sublimation gas storage container 21, the xenon difluoride gas sublimated from the solid state is temporarily stored. The xenon difluoride gas is gasified by decompressing the xenon difluoride container 20 with a dry pump 42 or the like and sublimating the solid xenon difluoride in the container 20. A solution of hydrofluoric acid (HF) is contained in the hydrogen fluoride container 30. The methyl alcohol container 31 contains a solution of methyl alcohol (CH ₃ OH). The dry pump 42 is used for the etching reaction chamber 10 and the containers 20, 30, 3
Depressurize 1. The exclusion device 49 renders the exhaust gas exhausted from the dry pump 42 harmless. Turbo molecular pump 4
0 and the rotary pump 41 decompress the etching reaction chamber 10 and the containers 20, 30, 31 at a higher speed than the dry pump 42. The control unit 502 includes a CPU 504, a ROM 506 that stores control programs and the like, a RAM 508 that temporarily stores data and the like, and an input port 510.
And an output port 512 and the like.

A third valve 23, a first flow meter 27, and a sixth valve 26 are provided in the pipe between the etching reaction chamber 10 and the xenon difluoride container 20. Between the etching reaction chamber 10 and the sublimation gas storage container 21, a pipe provided with a fourth valve 24, a first flow meter 27 and a sixth valve 26, and a pipe provided with a fifth valve 25 are provided. There is. A second flow meter 32 and a seventh valve 34 are provided in the pipe between the etching reaction chamber 10 and the hydrogen fluoride container 30. A pipe between the etching reaction chamber 10 and the methyl alcohol container 31 has a third flow meter 33 and an eighth valve 35.
Is provided. A ninth valve 43 is provided in the pipe between the etching reaction chamber 10 and the turbo molecular pump 40. A first throttle valve 91 and a tenth valve 44 are provided in a pipe between the etching reaction chamber 10 and the dry pump 42. In the etching reaction chamber 10,
The first pressure gauge 11 is connected. Etching reaction chamber 1
A first vacuum gauge 12 is connected to 0 via a twelfth valve 13. A nitrogen gas supply unit 93 is connected to the etching reaction chamber 10 via the second valve 14.

The etching reaction chamber 10 is provided with an etching end detector 97 for detecting the end of etching of the sample. The etching end detection unit 97 may be any unit that detects the end of etching of the portion of the sample to be etched by some means, or may be one that determines by setting some conditions. However, it is preferable to use the technique described in JP 2001-185530 A created by the present inventors.

The control unit 502 includes the above-mentioned valves 13,
14, 23 to 26, 34, 35, 43, 44, each pressure gauge 11, 22, each flow meter 27, 32, 33, each pump 40
˜42, the first vacuum gauge 12, the abatement device 49, the etching end detection unit 97, etc. are electrically connected. Control unit 50
2 has a function of monitoring and controlling the operation of each of these parts. In the etching reaction chamber 10, as shown in FIG. 2, a sample table 80, a shower plate 82,
Two blocking plates 83 are provided. Sample table 80
A sample 81 for manufacturing a structure by dry etching can be placed on the. It is preferable to provide radial grooves or a small number of minute projections on the surface of the sample table 80. Providing the groove or the protrusion can prevent the pressure difference between both surfaces of the sample 81. Therefore, even the sample 81 formed of a brittle material can be prevented from being damaged. In addition, the sample 81 is placed on the surface of the sample table 80.
Can be prevented from adhering to each other.

The shower plate 82 is formed in a disk shape and has a large number of gas supply ports 82a on the lower surface. It is preferable that the shower plate 82 be attached with a rotary shaft so as to be rotatable. Further, it is preferable that the joint between the rotary shaft and the disc be a swing seal so that the disc can swing.
By making the disk rotatable or swingable, the gas can be showered almost uniformly throughout the etching reaction chamber 10. Further, it is preferable that the gas supply pipe and the rotary shaft are formed separately. In this case, if the gas supply pipe is formed of soft piping and the joint between the soft piping and the disk is a fixed seal,
Gas leakage can be firmly prevented. Moreover, since it is not necessary to consider gas leakage at the joint of the rotary shaft, the structure of the motion seal can be simplified. Further, it is preferable that the soft pipe is wound around the swing central axis by the vibration angle.

The two blocking plates 83 are the shower plates 8
The linear gas flow from the second gas supply port 82a to the gas discharge port 10a is blocked. When the blocking plate 83 is provided, the gas flow direction in the etching reaction chamber 10 is dispersed in various directions. Therefore, the gas can be supplied almost uniformly to the entire sample 81 in the etching reaction chamber 10. Stop plate 8
When No. 3 is provided, the sample 81 can be etched substantially uniformly even when gas is continuously supplied to perform continuous etching.

As shown in FIG. 3, three blocking plates 85 are attached to the methyl alcohol container 31 to form a maze structure. By providing this blocking plate 85, it is possible to prevent the methyl alcohol solution from directly entering the pipe when the methyl alcohol solution bumps when the methyl alcohol container 31 is depressurized by the dry pump 42 or the like. As a result, it is possible to prevent the methyl alcohol solution from clogging the filter 84 in the pipe.

Next, for example, a method for manufacturing a silicon-based structure having a hollow space 120 shown in FIG. 6 by using the structure manufacturing apparatus of the first embodiment having the above-mentioned structure and a silicon-based material processing technique will be described with reference to FIG. ~ It demonstrates with reference to FIG. This silicon-based structure has a beam (beam) or mass (mass) A extending above the hollow space 120. This manufacturing method is
This is to be compared with the first background art shown in FIGS.

First, the following processing is performed by an apparatus different from the structure manufacturing apparatus of the first embodiment. First, for example, in a predetermined region on the silicon substrate 102 shown in FIG.
Silicon oxide layer 1 by the ical vapor deposition method etc.
08 is formed. After that, the silicon layer 112 is covered by the CVD method or the like so as to cover the silicon oxide layer 108.
To form.

The sample as shown in FIG. 4 obtained through the above steps is housed in the etching reaction chamber 10 of the structure manufacturing apparatus of the first embodiment shown in FIG. The following processing is performed in this structure manufacturing apparatus. First, in this structure manufacturing apparatus, the xenon difluoride gas for etching silicon is supplied to the etching reaction chamber 10 to supply the silicon layer 11
2 is locally dry-etched. Xenon difluoride gas selectively etches silicon (Si: including both polycrystalline silicon and single crystal silicon) to remove silicon oxide (SiO ₂ ), silicon nitride (SiN), and aluminum (Al). Do not etch. Specifically, the etching rate of silicon by xenon difluoride gas is about 4600Å / min, the etching rate of silicon oxide is about 0Å / min, the etching rate of silicon nitride is about 120Å / min, and The etching rate is about 0Å / min. However,
These values can be changed under various conditions.

As a method of locally dry etching, for example, a method of supplying a gas in a state where a mask is formed by a resist except a portion to be dry etched, a method of locally applying a gas to a portion to be dry etched, etc. However, the method is not limited to these. Any method may be used as long as it can locally perform dry etching. When masking with a resist, the resist must be a material that is hardly etched by a gas (xenon difluoride gas in this example). Thereby, as shown in FIG. 5, an etching hole 118 reaching the silicon oxide layer 108 is formed. As a result, part of the silicon oxide layer 108 is exposed. Then, xenon difluoride gas is discharged from the etching reaction chamber 10. Then, a mixed gas of methyl alcohol and hydrogen fluoride is supplied to the etching reaction chamber 10 to dry-etch the entire silicon oxide layer 108.

A mixed gas of methyl alcohol and hydrogen fluoride selectively etches silicon oxide (SiO ₂ ) to obtain silicon (Si: including both polycrystalline silicon and single crystal silicon) and silicon nitride (SiN). ) And aluminum (Al) are hardly etched. Specifically, the etching rate of silicon oxide with a mixed gas of methyl alcohol and hydrogen fluoride is about 1000 Å / min, the etching rate of silicon is about 0 Å / min, and the etching rate of silicon nitride is about 10 Å / min.
And the etching rate of aluminum is about 1Å / mi
It is a small value of n or less. However, these values may vary depending on various conditions. Silicon oxide layer 10
8 is finally removed so that the space 1 as shown in FIG.
It is a layer for producing 20. This layer is commonly referred to as the "sacrificial layer". As a result, as shown in FIG. 6, a silicon-based structure having the hollow space 120 is manufactured.

This structure is used, for example, as an acceleration sensor. When used as an acceleration sensor,
A portion A of the silicon layer 112 is used as a beam or mass that is displaced when acceleration acts. For example, when acceleration in the direction perpendicular to the substrate surface of the silicon substrate 102 acts, the mass A is displaced in the direction perpendicular to the substrate surface. The applied acceleration can be detected by detecting the displacement of the mass A as a change in the capacitance between the electrode pair (not shown). Alternatively, the beam A bends when acceleration in a direction perpendicular to the substrate surface of the silicon substrate 102 acts. The acting acceleration can be detected by detecting the deflection of the beam A as a resistance change of the piezoresistor not shown. It is also possible to detect the acceleration in the direction parallel to the substrate surface of the silicon substrate 102.

Next, the above-mentioned processing by the structure manufacturing apparatus of the first embodiment will be described more specifically with reference to FIG.
Initially, all valves are closed. The following processing may be performed by the control unit 502 by a control program or the like, or a part of the control may be manually performed by the operator. First, the first throttle valve 91 and the first
The 0 valve 44, the sixth valve 26, and the third valve 23 are opened, the dry pump 42 is driven, and the etching reaction chamber 1
0 and the pressure of the xenon difluoride container 20 is reduced. Xenon difluoride sublimes at a pressure of 3.8 Torr or less. Therefore, this depressurization process causes the solid xenon difluoride contained in the xenon difluoride container 20 to sublimate into gas. This xenon difluoride gas is guided to the etching reaction chamber 10 by the suction force of the dry pump 42, and is further discharged via the dry pump 42. As a result, the gas or the like remaining in the etching reaction chamber 10 is expelled. After discharging, the tenth valve 44, the sixth valve 26, and the third valve 23 are closed.

Next, the second valve 14 is opened, and nitrogen gas is supplied to the etching reaction chamber 10 from the nitrogen gas supply portion 93 to bring the inside of the etching reaction chamber 10 to atmospheric pressure. The door of the etching reaction chamber 10 is opened under atmospheric pressure, and a sample 81 as shown in FIG. 2 is placed on the sample table 80. After mounting the sample 81, the door is closed and the second valve 14 is closed.

Next, the first throttle valve 91 and the first throttle valve 91
The 0 valve 44, the third valve 23, and the sixth valve 26 are opened, the dry pump 42 is driven, and the etching reaction chamber 10 is opened.
And the pressure of the xenon difluoride container 20 is reduced. As a result, the solid xenon difluoride contained in the xenon difluoride container 20 sublimes into gas, and the etching reaction chamber 1
It is introduced within 0. The pressure in the etching reaction chamber 10 is monitored by the first pressure gauge 11, and when the predetermined pressure is reached, the third pressure
The valve 23 and the sixth valve are closed, and the xenon difluoride gas is confined in the etching reaction chamber 10. The xenon difluoride gas locally etches the silicon layer 112 (see FIG. 5) of the sample 81 in the etching reaction chamber 10 to form the etching hole 118. The reaction equation of this etching is represented by the following equation (1). 2XeF ₂ + Si → 2Xe + SiF ₄ (1)

When the etching completion detecting unit 97 detects that the etching of the portion of the silicon layer 112 that needs etching with the xenon difluoride gas is completed, the tenth step is performed.
The valve 44 is opened, and the xenon difluoride gas in the etching reaction chamber 10 is discharged through the dry pump 42 and the abatement device 49. The etching end detection unit 97 may not be provided. For example, the etching period data calculated or stored by the control unit 502 may be used. The etching period data is data which is calculated during the operation of the apparatus from the time when the etching is started to the time when the etching is estimated under a predetermined condition, or is calculated and stored in advance. The predetermined condition is, for example, the size of the sample, the amount of gas supplied to the etching reaction chamber, the type of gas, or the like.

Next, the first throttle valve 91 and the first throttle valve 91
The 0 valve 44, the eighth valve 35, and the seventh valve 34 are opened, and the dry pump 42 evacuates. Then, the methyl alcohol solution in the methyl alcohol container 31 is evaporated, and the hydrogen fluoride solution in the hydrogen fluoride container 30 is evaporated. The flow rate of the evaporated methyl alcohol gas is monitored by the third flow meter 33, and the flow rate is adjusted if necessary. Further, the flow rate of the evaporated hydrogen fluoride gas is monitored by the second flow meter 32, and the flow rate is adjusted if necessary. A mixed gas of methyl alcohol and hydrogen fluoride whose flow rate is adjusted is supplied to the etching reaction chamber 10. After that, the eighth valve 35 and the seventh
The valve 34 is closed and the mixed gas of methyl alcohol and hydrogen fluoride is discharged from the etching reaction chamber 10. As a result, the gas or the like remaining in the etching reaction chamber 10 is expelled.

Next, the ninth valve 43 is opened, and the inside of the etching reaction chamber 10 is evacuated to a high vacuum by the turbo molecular pump 40 and the rotary pump 41. Next, the ninth valve 43 is closed,
The tenth valve 44, the eighth valve 35, and the seventh valve 34 are opened, and the dry pump 42 is evacuated to evaporate the methyl alcohol solution in the methyl alcohol container 31 and the hydrogen fluoride solution in the hydrogen fluoride container 30. Evaporate. The flow rate of the evaporated methyl alcohol gas is monitored by the third flow meter 33, and the flow rate is adjusted if necessary. Further, the flow rate of the evaporated hydrogen fluoride gas is monitored by the second flow meter 32, and the flow rate is adjusted if necessary. The mixed gas of methyl alcohol and hydrogen fluoride, the flow rate of which was adjusted, was used as the etching reaction chamber 10.
Is supplied to.

The pressure in the etching reaction chamber 10 is monitored by the first pressure gauge 11, the first throttle valve 91 is adjusted,
Hold at a predetermined pressure. As a result, the silicon oxide layer 108 (see FIG. 5) of the sample is etched with the mixed gas.
In this case, the reactions represented by the following formulas (2) and (3) occur. "M" in Formula (2) and Formula (3) represents methyl alcohol. M + 2HF → HF ₂ ⁻ + MH ⁺ (2) SiO ₂ + 2HF ₂ ⁻ + 2MH ⁺ → SiF ₄ + 2H ₂ O + 2M (3)

When the etching completion detecting unit 97 detects that the etching of the silicon oxide layer 108 by the mixed gas is completed, the eighth valve 35 and the seventh valve 34 are closed, and methyl alcohol and fluorine are removed from the etching reaction chamber 10. Dry gas 42 and abatement device 49 for mixed gas of hydrogen fluoride
Exhaust through. Also in this case, the etching period data calculated or stored by the control unit 502 may be used without using the etching end detection unit 97.

In the above processing, the etching reaction chamber 10, the methyl alcohol container 31, the hydrogen fluoride container 3
As the means for reducing the pressure of the xenon difluoride container 20 and the like, a high-speed pressure reducing means in which the turbo molecular pump 40 and the rotary pump 41 are connected may be used instead of the dry pump 42. In this case, when reducing the pressure, the tenth valve 4
Instead of 4, the ninth valve 43 is opened.

Next, a method for manufacturing the silicon-based structure having the hollow space 220 shown in FIG. 13 by using the structure manufacturing apparatus of the first embodiment having the above-mentioned configuration and the processing technique for other silicon-based materials. Will be described with reference to FIGS. This silicon-based structure has a diaphragm B located above the hollow space 220. This manufacturing method is to be compared with the second background art shown in FIGS.

First, the following processing is performed by an apparatus different from the structure manufacturing apparatus of the first embodiment. Impurities are locally implanted into the single crystal silicon substrate 202 shown in FIG. 7 to form the lower electrode 204. The lower silicon nitride layer 210 is formed by nitriding the surface of the silicon substrate 202. A polycrystalline silicon layer 208 is formed in a predetermined region on the lower silicon nitride layer 210 by, for example, the CVD method. In this example, the polycrystalline silicon layer 208 serves as a sacrificial layer. An upper first silicon nitride layer 212 is formed so as to cover the polycrystalline silicon layer 208. Upper first silicon nitride layer 212
The upper electrode 206 is formed in a predetermined region above. The upper electrode 206 is made of polycrystalline silicon or the like. Upper electrode 20
An upper second silicon nitride layer 214 is formed so as to cover 6.

After that, as shown in FIG.
6 and the contact hole 222 on the predetermined region of the lower electrode 204.
a and 222b are formed. Then, as shown in FIG.
An aluminum layer 216 to be a wiring layer is formed on the surface of the sample. Then, as shown in FIG.
16 is patterned to form a wiring layer 216a that contacts the upper electrode 206 and a wiring layer 216 that contacts the lower electrode 204.
b is formed. Then, as shown in FIG. 11, in the portion where the upper electrode 206 does not exist, the upper silicon nitride layer 21 is formed.
2, 214 is etched to form a polycrystalline silicon layer 208
To form etching holes 218. This allows
Part of the polycrystalline silicon layer 208 is exposed. As a result,
The exposed portion of the polycrystalline silicon layer 208 is oxidized to form a natural oxide film (silicon oxide) 219.

The sample shown in FIG. 11 obtained through the above steps is housed in the etching reaction chamber 10 of the structure manufacturing apparatus of the first embodiment shown in FIG. The following processing is performed in this structure manufacturing apparatus. First, the structure manufacturing apparatus supplies a mixed gas of methyl alcohol and hydrogen fluoride to the etching reaction chamber 10 to dry-etch the natural oxide film (silicon oxide) 219 shown in FIG. As described above, the mixed gas of methyl alcohol and hydrogen fluoride selectively etches silicon oxide and hardly etches silicon (polycrystalline or single crystal), silicon nitride, and aluminum. As a result, a part of the silicon layer 208 which is a sacrifice layer is exposed. Then, a mixed gas of methyl alcohol and hydrogen fluoride is discharged from the etching reaction chamber 10. Then, a xenon difluoride gas is supplied to the etching reaction chamber 10 so that the silicon layer 20 shown in FIG.
8 is dry-etched. As a result, the state shown in FIG. 12 is obtained. Xenon difluoride gas, as described above,
Selectively etches silicon (polycrystal, single crystal), and hardly etches silicon oxide, silicon nitride and aluminum. After that, a sealing layer 224 as shown in FIG. 13 is formed by a device different from the structure manufacturing device of the first embodiment to seal the etching hole 218. As a result, a silicon-based structure having the hollow space 220 is manufactured. This structure functions as a pressure sensor.

In this structure, the upper silicon nitride layer 21
2, 214, the upper electrode 206, and the predetermined portion B of the sealing layer 224 function as a diaphragm. The space 220 from which the silicon oxide layer 208, which is a sacrificial layer, is removed is a sealed space and functions as a pressure reference chamber. According to this structure, the diaphragm B bends according to the difference between the pressure applied to the diaphragm B and the reference pressure. When the diaphragm B bends, the distance between the upper electrode 206 and the lower electrode 204 changes. When the distance between the electrodes 206 and 204 changes,
The capacitance between both electrodes 206 and 204 changes. The amount of pressure acting on the diaphragm B can be detected by detecting the amount of change in the capacitance.

Next, the above-described processing by the structure manufacturing apparatus of the first embodiment will be described more specifically with reference to FIG.
Initially, all valves are closed. The following processing may be performed by the control unit 502 by a control program or the like, or a part of the control may be manually performed by the operator. First, the first throttle valve 91 and the first
The 0 valve 44, the 8th valve 35, and the 7th valve 34 are opened, the dry pump 42 evacuates, the methyl alcohol solution in the methyl alcohol container 31 is evaporated, and the hydrogen fluoride solution in the hydrogen fluoride container 30 is removed. Evaporate. The flow rate of the evaporated methyl alcohol gas is monitored by the third flow meter 33, and the flow rate is adjusted if necessary. Further, the flow rate of the evaporated hydrogen fluoride gas is monitored by the second flow meter 32, and the flow rate is adjusted if necessary. A mixed gas of methyl alcohol and hydrogen fluoride whose flow rate is adjusted is supplied to the etching reaction chamber 10. After that, the eighth valve 35 and the seventh valve 3
4 is closed, and a mixed gas of methyl alcohol and hydrogen fluoride is discharged from the etching reaction chamber 10. As a result, the gas or the like remaining in the etching reaction chamber 10 is expelled. In addition, the inside of the etching reaction chamber 10 is 1 × 10 ⁻² Pa.
When the following vacuum state is required, the tenth valve 44 is closed, the ninth valve 43 is opened, and the turbo molecular pump 40 and the rotary pump 41 are evacuated.

Next, the ninth valve 43 and the tenth valve 44
Is closed, the second valve 14 is opened, and nitrogen gas is supplied from the N gas supply unit 93 to the etching reaction chamber 10 to bring the inside of the etching reaction chamber 10 to atmospheric pressure. With the atmospheric pressure kept, the door of the etching reaction chamber 10 was opened and the sample 8 as shown in FIG.
1 is placed on the sample table 80. After mounting the sample 81, the door is closed and the second valve 14 is closed. Next, the ninth
The valve 43 is opened, and the inside of the etching reaction chamber 10 is set to a high vacuum by the turbo molecular pump 40 and the rotary pump 41.
Next, the ninth valve 43 is closed and the tenth valve 44 and the eighth valve 43 are closed.
The valve 35 and the seventh valve 34 are opened, and the dry pump 42
Is evacuated to evaporate the methyl alcohol solution in the methyl alcohol container 31 and evaporate the hydrogen fluoride solution in the hydrogen fluoride container 30. The flow rate of the evaporated methyl alcohol gas is monitored by the third flow meter 33, and the flow rate is adjusted if necessary. Further, the flow rate of the evaporated hydrogen fluoride gas is monitored by the second flow meter 32, and the flow rate is adjusted if necessary. A mixed gas of methyl alcohol and hydrogen fluoride whose flow rate is adjusted is supplied to the etching reaction chamber 10.

The pressure in the etching reaction chamber 10 is monitored by the first pressure gauge 11, the first throttle valve 91 is adjusted,
Hold at a predetermined pressure. As a result, the natural oxide film (silicon oxide) 219 (see FIG. 11) of the sample 81 is etched with the mixed gas. When the etching completion detecting unit 97 detects that the etching of the natural oxide film 219 by the mixed gas is completed, the eighth valve 35 and the seventh valve 34 are closed to remove methyl alcohol and hydrogen fluoride from the etching reaction chamber 10. Dry gas 42 and abatement device 4 for mixed gas
Discharge through 9. Also in the above case, the etching period data calculated or stored by the control unit 502 may be used without using the etching end detection unit 97.

Next, the first throttle valve 91 and the first throttle valve 91
0 valve 44, 5th valve 25, 4th valve 24 and 3rd valve
The valve 23 is opened and the dry pump 42 is driven to depressurize the etching reaction chamber 10, the sublimation gas storage container 21, and the xenon difluoride container 20. Xenon difluoride is 3.8T
In order to sublimate at a pressure of orr or less, this treatment sublimes the solid xenon difluoride contained in the xenon difluoride container 20. After that, the third valve 23
And the sublimation gas storage container 21 and the etching reaction chamber 10 are closed.
The sublimated xenon difluoride gas is discharged. As a result, the gas remaining in the sublimation gas storage container 21 and the etching reaction chamber 10 is expelled. After discharging, the first
The 0 valve 44, the fifth valve 25, and the fourth valve 24 are closed.

Next, the first throttle valve 91 and the first throttle valve 91
0 valve 44, 5th valve 25 and 4th valve 24 are opened, dry pump 42 is driven, and etching reaction chamber 10
Then, the sublimation gas storage container 21 and the xenon difluoride container 20 are depressurized. After reducing the pressure, the fifth valve 25 is closed and the third valve 23 is opened. As a result, the fifth valve 25 is closed and the third valve 23 and the fourth valve 24 are opened. As a result, the sublimation gas storage container 21 in the reduced pressure state and the xenon difluoride container 20 communicate with each other. Therefore, the solid xenon difluoride contained in the xenon difluoride container 20 is sublimated, and the sublimated xenon difluoride gas is stored in the sublimation gas storage container 21. The pressure in the sublimation gas storage container 21 is monitored by the second pressure gauge 22, and when the predetermined pressure is reached, the first
The 0 valve 44 and the third valve 23 are closed, and the fifth valve 25
And the xenon difluoride gas is introduced into the etching reaction chamber 10 from the sublimation gas storage container 21. The pressure in the etching reaction chamber 10 is monitored by the first pressure gauge 11, and when a predetermined pressure is reached, the fifth valve 25 is closed and the xenon difluoride gas is confined in the etching reaction chamber 10. Due to the xenon difluoride gas, the polycrystalline silicon layer 208 which is the sacrifice layer of the sample 81 in the etching reaction chamber 10
(See FIG. 11) is dry etched.

When the etching completion detecting unit 97 detects that the etching of the silicon layer 112 by the xenon difluoride gas is completed, the tenth valve 44 is opened to dry the xenon difluoride gas in the etching reaction chamber 10. It discharges through the pump 42 and the abatement device 49. After being discharged, the fourth valve 24 and the fifth valve 25 are opened again to supply the xenon difluoride gas into the etching reaction chamber 10. Also in the above case, the etching period data calculated or stored by the control unit 502 may be used without using the etching end detection unit 97.

In this embodiment, the operation of supplying xenon difluoride gas to the etching reaction chamber 10, holding and discharging it is repeated, and the polycrystalline silicon layer (sacrificial layer) 208 is selectively formed by a so-called pulse etching method. Etching. A method of continuously supplying gas while continuously monitoring the flow rate with the first flow meter 27 may be used. By using the pulse etching method, the amount of xenon difluoride gas used can be saved.

When the structure manufacturing apparatus of the first embodiment described above is used, wet etching need not be performed to remove silicon oxide. Therefore, it is not necessary to perform the step of cleaning the etching liquid attached to the sample and the step of drying the sample after the cleaning. Therefore, the manufacturing process of the silicon-based structure can be simplified. In addition, since wet etching is not required to remove silicon oxide, the possibility of sticking phenomenon during manufacturing can be extremely reduced. Therefore, it is possible to reduce the occurrence of defective products during manufacturing. In other words, the rigidity of the structure can be reduced and the shape and size of the structure can be reduced as compared with the case where wet etching is performed. Therefore, it is possible to realize a structure that functions as a highly sensitive or highly accurate sensor or actuator. Further, silicon and silicon oxide can be dry-etched in the same etching reaction chamber 10 (see FIG. 1). Therefore, the troublesome work of transferring the sample between the etching reaction chamber of the silicon dry etching apparatus and the etching reaction chamber of the silicon oxide dry etching apparatus becomes unnecessary. Therefore, the manufacturing process can be simplified. Since it is not necessary to transfer the sample between the etching reaction chambers, the sample is not exposed to the outside air during that time. Therefore, it is possible to reduce the occurrence of defective products during manufacturing of the silicon-based structure or the occurrence of defective products during use. In particular, it is possible to prevent the natural oxide film from being formed again on the surface of the sample after etching the natural oxide film formed on the surface of silicon.

The xenon difluoride gas and the mixed gas of hydrogen fluoride gas and methyl alcohol hardly etch the aluminum material. Therefore, these gases can form the aluminum layer 216 as shown in FIG. 9 before etching the silicon oxide 219 as the natural oxide film and the silicon layer 208 as the sacrificial layer as shown in FIG. Therefore, it is possible to prevent the aluminum 216 from entering the hollow space 220 as shown in FIG. 12 after the silicon layer 208 is removed by dry etching. Therefore, it is possible to reduce the occurrence of defective products during manufacturing or the occurrence of defective products during use.

(Second Embodiment) FIG. 14 shows the structure of an apparatus for manufacturing a silicon-based structure according to the second embodiment. In the following, in principle, the description of the same contents as in the first embodiment will be omitted. The structure manufacturing apparatus according to the second embodiment includes a coating chamber 50, an organosilicon compound container 60, a water container 61 and the like in addition to the constituent elements of the structure manufacturing apparatus according to the first embodiment. A liquid organosilicon compound is contained in the organosilicon compound container 60. The organic silicon compound, for example, tridecafluoro-1,1,2,2, - tetramethyl-bi mud octyl trichlorosilane _{(C 8 F 13 H 4 SiCl} 3), Ofuta decyl trichlorosilane _{(C 18} H 37 SiCl _3), etc. Can be used. Water (H ₂ O) is contained in the water container 61. A third pressure gauge 51 is connected to the coating chamber 50. The coating chamber 50 has a first
The second vacuum gauge 52 is connected via the 1-valve 53. A nitrogen gas introducing unit 94 is connected to the coating chamber 50 via a twelfth valve 54.

The coating chamber 50 includes a thirteenth valve 62.
It is connected to the organic silicon compound container 60 via.
The coating chamber 50 is connected to the water container 61 via the fourteenth valve 63. The coating chamber 50 is the first
The turbo molecular pump 40 is connected via a 5-valve 45. The coating chamber 50 has a throttle valve 92.
And the dry pump 42 via the sixteenth valve 46. The control unit 502 includes the valves 45 and 4 described above.
6, 53, 54, 62 to 63, 91 and the third pressure gauge 51,
It is also electrically connected to the second vacuum gauge 52 and the like. The control unit 502 has a function of monitoring and controlling the operation of each of these units.

The structure manufacturing apparatus of the second embodiment performs the same processing operation as that of the structure manufacturing apparatus of the first embodiment, and then performs the following processing operation. First, the twelfth valve 54 is opened, and nitrogen gas is supplied from the nitrogen gas introducing portion 94 to the coating chamber 50 to bring the inside of the coating chamber 50 to atmospheric pressure. Then, the sample is moved from the etching reaction chamber 10 to the coating chamber 50, and the sample is fixed on the sample table in the coating chamber 50. Specifically, this sample is a sample having a silicon beam and a mass structure A as shown in FIG. Alternatively, the sample is in a state before the etching hole 218 as shown in FIG. The inside of the coating chamber 50 has almost the same structure as the inside of the etching reaction chamber 10 shown in FIG.

Next, the twelfth valve 54 is closed, the fourteenth valve 63 is opened, the water in the water container 61 is evaporated and introduced into the coating chamber 50, and the surface of the structure is exposed to water vapor. Next, the thirteenth valve 62 is opened, the organosilicon compound in the organosilicon compound container 60 is evaporated and introduced into the coating chamber 50, and the surface of the structure is exposed to the organosilicon compound gas. As a result, the surface of the structure is exposed to the mixed gas of water vapor and the organosilicon compound. As a result, the surface of the structure is water-repellently coated by the condensation reaction between the hydroxyl group and the reactive group of the organosilicon compound. The details of the water-repellent coating treatment described above are created by the present inventors in JP-A-11-288.
No. 929 publication.

According to the structure manufacturing apparatus of the second embodiment, in addition to the effects described in the description of the first embodiment, it is possible to more effectively suppress the occurrence of the sticking phenomenon when the silicon-based structure is used. can get. According to this structure manufacturing apparatus, the surface of the silicon-based structure can be coated with a water-repellent film. Therefore, the water repellency of the silicon-based structure can be improved. Therefore, for example, even when using the structure in an environment where dew condensation is likely to occur,
It is possible to prevent liquid from adhering to the structure and causing the sticking phenomenon due to the surface tension of the liquid. Therefore, it is possible to reduce the occurrence of defective products during use.

(Third Embodiment) FIG. 15 shows the structure of a silicon-based structure manufacturing apparatus of the third embodiment. Below, in principle, the description of the same contents as in the first and second embodiments will be omitted. The structure manufacturing apparatus according to the third embodiment includes, in addition to the constituent elements of the structure manufacturing apparatus according to the second embodiment, a preliminary chamber 70, first and second connecting portions 75 and 76, and first and second. Opening and closing means 98, 99,
The sample transport means 96 and the like are provided. The first connecting portion 75 is
The etching reaction chamber 10 and the preliminary chamber 70 are connected to each other by blocking them from the outside air. The second connection part 76 connects the preliminary chamber 70 and the coating chamber 50 by blocking them from the outside air. The first opening / closing means 98 can switch between the etching reaction chamber 10 and the preliminary chamber 70 between an open state and a closed state. Second opening / closing means 99
Can switch between the preliminary chamber 70 and the coating chamber 50 between an open state and a closed state.

The sample carrying means 96 is the etching reaction chamber 1
It is possible to transfer the sample between 0 and the preliminary chamber 70 and between the preliminary chamber 70 and the coating chamber 50. In the spare room 70,
The fourth pressure gauge 71 is connected. A third vacuum gauge 72 is connected to the preliminary chamber 70 via a seventeenth valve 73. A nitrogen gas introducing portion 95 is connected to the preliminary chamber 70 via an eighteenth valve 74. The spare room 70 is the 19th
The turbo molecular pump 40 is connected via a valve 47. The preliminary chamber 70 is connected to the dry pump 42 via the twentieth valve 48.

The structure manufacturing apparatus of the third embodiment performs the same processing operation as that of the structure manufacturing apparatus of the first embodiment, and then performs the following processing operations. First, the nineteenth valve 47 is opened, and the turbo molecular pump 40 and the rotary pump 41 are used to operate the auxiliary chamber 7.
The inside of 0 is evacuated. The pressure in the preliminary chamber 70 is monitored by the fourth pressure gauge 71, and when a predetermined pressure is reached, the sample transfer means 9
The sample is moved from the etching reaction chamber 10 to the preparatory chamber 70 through the first connecting part 75 according to 6. After a predetermined time, the sample transfer means 96 moves the sample from the preliminary chamber 70 to the coating chamber 50 through the second connecting portion 75. Then, the processing operation described in the processing operation of the structure manufacturing apparatus of the second embodiment shown in FIG. 14 is performed.

According to the structure manufacturing apparatus of the third embodiment, in addition to the effects described in the description of the first and second embodiments, the structure after the dry etching in the etching reaction chamber 10 is completed is exposed to the outside air. It can be transferred to the coating chamber 50 without being exposed to water, and the effect of preventing oxidation of the structure and the like can be obtained. Further, since the preliminary chamber 70 is provided, it is easier to transfer the structure between the etching reaction chamber 10 and the coating chamber 50.

Specific examples of the present invention have been described above in detail, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. In the above embodiment, the mass and beam structure A shown in FIG.
The method for manufacturing the hollow silicon-based structure having the structure and the hollow silicon-based structure having the diaphragm structure B shown in FIG. 13 has been described as an example, but these structures can be manufactured by the structure manufacturing apparatus of the above embodiment. It is just one example of a structure. A silicon-based material processing apparatus embodying the present invention, a silicon-based structure manufacturing apparatus, and a manufacturing method thereof are
It is suitable for manufacturing various structures containing at least silicon and silicon oxide during manufacturing. In addition to the xenon difluoride (XeF ₂ ) gas used in the above examples, bromine trifluoride (BrF ₃ ) gas is preferably used. In addition to the mixed gas of methyl alcohol (CH ₃ OH) and hydrogen fluoride (HF) used in the above examples, it is preferable to use a mixed gas of water vapor (H ₂ O) and hydrogen fluoride (HF). . In addition to methyl alcohol and water vapor, it is also preferable to use a gas that produces HF ₂ by mixing with hydrogen fluoride (HF). Of course, other than the above-mentioned gases, any gas may be used as long as it satisfies the requirements of the claims.

Further, for example, a methyl alcohol container 31
In order to prevent the solution of methyl alcohol that has been bumped inside from clogging the inside of the pipe, it can be carried out in the following manner instead of the configuration of FIG. (First Modification) As shown in FIG. 16, the cord heater 86 is attached to the pipe and the etching reaction chamber 10, and the pipe and the etching reaction chamber 10 are attached.
Methyl alcohol container 3 due to bumping by heating
The liquid that has entered the pipe from 1 may be vaporized. (Second Modification) As shown in FIG. 17, a reservoir tank 87 is provided between the methyl alcohol container 31 and the filter 84, and after the reservoir tank 87 is completely vaporized, the vaporized gas is etched. May be supplied to. (Third Modification) As shown in FIG. 18, a replenishment container 88 and a control valve 89 are provided in front of the methyl alcohol container 31, and the replenishment container 88 is adjusted according to the evaporation rate of the liquid in the methyl alcohol container 31.
The flow rate of the raw material supplied from the control valve 89 may be adjusted. (Fourth Modification) As shown in FIG. 19, bumping is prevented when the sponge or the fiber 90 is soaked in the solution in the methyl alcohol container 31 so that the liquid surface does not become wavy and is evacuated by the dry pump 42. You may.

Further, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technique illustrated in the present specification or the drawings can simultaneously achieve a plurality of objects, and achieving the one object among them has technical utility.

[Brief description of drawings]

FIG. 1 shows the configuration of a silicon-based structure manufacturing apparatus according to a first embodiment.

FIG. 2 shows the configuration of an etching reaction chamber of the silicon-based structure manufacturing apparatus of the first embodiment.

FIG. 3 shows a configuration between a methyl alcohol container and a dry pump of the silicon-based structure manufacturing apparatus of the first embodiment.

FIG. 4 shows a part of the manufacturing process of the first silicon-based structure using the silicon-based structure manufacturing apparatus of the first embodiment and another silicon-based material processing technique (1).

FIG. 5 shows a part of the manufacturing process (2).

FIG. 6 shows a part of the manufacturing process (3).

FIG. 7 shows a part of the manufacturing process of the second silicon-based structure using the silicon-based structure manufacturing apparatus of the first embodiment and the processing technique of other silicon-based materials (1).

FIG. 8 shows a part of the manufacturing process (2).

FIG. 9 shows a part of the manufacturing process (3).

FIG. 10 shows a part of the manufacturing process (4).

FIG. 11 shows a part of the manufacturing process (5).

FIG. 12 shows a part of the manufacturing process (6).

FIG. 13 shows a part of the manufacturing process (7).

FIG. 14 shows a structure of a silicon-based structure manufacturing apparatus according to a second embodiment.

FIG. 15 shows a structure of a silicon-based structure manufacturing apparatus of a third embodiment.

FIG. 16 shows a first modification of the configuration between the methyl alcohol container and the dry pump.

FIG. 17 shows a second modification of the configuration between the methyl alcohol container and the dry pump.

FIG. 18 shows a third modification of the configuration between the methyl alcohol container and the dry pump.

FIG. 19 shows a fourth modification of the configuration between the methyl alcohol container and the dry pump.

FIG. 20 shows a part of the manufacturing process of the conventional first silicon-based structure (1).

FIG. 21 shows a part of the manufacturing process (2).

FIG. 22 shows a part of the manufacturing process (3).

FIG. 23 shows a part of the manufacturing process of the conventional second silicon-based structure (1).

FIG. 24 shows a part of the manufacturing process (2).

FIG. 25 shows a part of the manufacturing process (3).

FIG. 26 shows a part of the manufacturing process (4).

[Explanation of symbols]

10: Etching reaction chamber 20: Xenon difluoride container 21: Sublimation gas storage container 23-26, 34, 35: Valve 30: Hydrogen fluoride container 31: Methyl alcohol container 42: Dry pump 49: Harmful device 502: Control unit

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takanori Mizuno, Nagakute-cho, Aichi-gun, Aichi, Japan 1-41 Yokomichi, Yokouchi Central Research Institute Co., Ltd. (72) Inventor, Katsuji Okuda, Aichi-gun, Nagakute-cho, Aichi-gun 1 of 41 Yorokodo, Toyota Central Research Institute Co., Ltd. (72) Inventor Masayuki Matsui, Nagakute-cho, Aichi-gun, Aichi-gun, Nagatoji 1 of 41 Yokochi Central Research Institute, Ltd. (72) Inventor, Yasuhiko Suzuki Aichi-gun, Aichi Nagakute-machi, Oita, Nagaminate, Yokomichi 41-1, Toyota Central Research Institute Co., Ltd. (56) Reference JP-A-3-185715 (JP, A) JP-A-10-209088 (JP, A) JP-A-9-102490 ( JP, A) JP 11-17245 (JP, A) JP 8-195381 (JP, A) JP 11-274142 (JP, A) JP 59-224129 (JP, A) JP-A-2001-15481 (JP, A) JP-A-9-321025 (JP, A) JP-A-9-162462 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B81C 1 / 00 H01L 21/302 201

Claims (9)

(57) [Claims] 1. A first gas supply unit, a second gas supply unit,
An etching reaction chamber for performing gas etching, a selective communication unit, and a gas discharge unit are provided. The first gas is a gas for etching silicon, and the second gas is a gas for etching silicon oxide and hardly etching silicon. The selective communication means selectively communicates the etching reaction chamber with either the first gas supply unit or the second gas supply unit, and the gas discharge unit discharges the gas in the etching reaction chamber and discharges at high speed. An apparatus for processing a silicon-based material, characterized by having a means and a low speed discharging means. 2. A first gas supply unit, a second gas supply unit,
An etching reaction chamber for performing gas etching, a selective communication unit, and a gas discharge unit are provided. The first gas is a gas that etches silicon oxide and hardly etches silicon nitride, and the second gas etches silicon. Is a gas that hardly etches silicon nitride, the selective communication means selectively communicates the etching reaction chamber with either the first gas supply part or the second gas supply part, and the gas discharge means is the gas discharge means in the etching reaction chamber. An apparatus for processing a silicon-based material, which has a high-speed discharging means and a low-speed discharging means while discharging gas. 3. A second silicon-based material on a first silicon-based material
The material is formed and the second silicon-based material is the third silicon-based
Hollow silicon-based structure by processing sample covered with material
A device for manufacturing First gas supply unit, second gas supply unit, and gas etching
Etching reaction chamber, selective communication means, and gas discharge
Equipped with means, The first gas is a gas that exposes part of the second silicon-based material.
Is The second gas etches the second silicon-based material to remove the first gas.
And third silicon material Gas that hardly etches
Is The selective communication means connects the etching reaction chamber to the first gas supply unit.
Selectively communicate with any of the second gas supply units, The gas discharging means discharges the gas in the etching reaction chamber.
At the same time, have a high-speed discharging means and a low-speed discharging means.
Characteristic silicon-based structure manufacturing equipment. 4. A first gas supply unit, a second gas supply unit,
An etching reaction chamber for performing gas etching, a selective communication unit, a gas discharge unit, a container containing an organosilicon compound, a container containing water, a gas conversion unit, a coating chamber, a connecting portion, and an opening / closing unit. And a sample transfer means, the first gas is a gas for etching silicon, the second gas is a gas for etching silicon oxide and hardly etching silicon, and the selective communication means is for etching the etching reaction chamber. The first gas supply section and the second gas supply section are selectively communicated with each other, the gas discharge means discharges the gas in the etching reaction chamber, and the gas conversion means is contained in the container of the organosilicon compound. The water stored in the container for storing the organosilicon compound and water is converted into a gas, the gas converted by the gas conversion means is introduced into the coating chamber, and the connecting portion is The etching reaction chamber and the coating chamber are connected to each other by shutting them off from the outside air, the opening / closing means can switch between the etching reaction chamber and the coating chamber between an open state and a closed state, and the sample transfer means is connected to the etching reaction chamber. A silicon-based material processing apparatus, which is capable of transporting a sample between coating chambers. 5. A first gas supply unit, a second gas supply unit,
An etching reaction chamber for performing gas etching, a selective communication unit, a gas discharge unit, a container containing an organosilicon compound, a container containing water, a gas conversion unit, a coating chamber, a connecting portion, and an opening / closing unit. And a sample transfer means, the first gas is a gas that etches silicon oxide and hardly etches silicon nitride, and the second gas is a gas that etches silicon and barely etches silicon nitride. The communication means selectively communicates the etching reaction chamber with either the first gas supply unit or the second gas supply unit, the gas discharge unit discharges the gas in the etching reaction chamber, and the gas conversion unit uses the organosilicon. Converts the water in the storage container for the organosilicon compound and water in the storage container for the compound into a gas, and the coating chamber uses the gas converted by the gas conversion means. Introduced, the connection part connects the etching reaction chamber and the coating chamber by blocking them from the outside air, and the opening / closing means can switch the etching reaction chamber and the coating chamber between the open state and the closed state. The means is capable of transporting a sample between the etching reaction chamber and the coating chamber, and is a silicon-based material processing apparatus. 6. A second silicon-based material on a first silicon-based material
The material is formed and the second silicon-based material is the third silicon-based
Hollow silicon-based structure by processing sample covered with material
A device for manufacturing First gas supply unit, second gas supply unit, and gas etching
Etching reaction chamber, selective communication means, and gas discharge
Means, container for containing organosilicon compound, and water
Connecting container, gas conversion means, coating chamber
A part, an opening / closing means, and a sample transfer means, The first gas is a gas that exposes part of the second silicon-based material.
Is The second gas etches the second silicon-based material to remove the first gas.
And a gas that hardly etches the third silicon-based material
Is The selective communication means connects the etching reaction chamber to the first gas supply unit.
Selectively communicate with any of the second gas supply units, The gas discharge means discharges the gas in the etching reaction chamber, The gas conversion means is an organic container in the container for the organosilicon compound.
Storage of iodine compounds and water Converts the water in the container into gas, The gas converted by the gas conversion means is introduced into the coating chamber.
Entered, The connecting part is located between the etching reaction chamber and the coating chamber.
Cut off from the air and connect, The opening / closing means connects between the etching reaction chamber and the coating chamber.
Can be switched between open and closed states, The sample transfer means consists of an etching reaction chamber and a coating chamber.
Silicon system characterized by being able to transfer samples between
Structure manufacturing equipment. 7. The preparatory chamber is further provided, and the connecting part connects the etching reaction chamber and the preparatory chamber and the preparatory chamber and the coating chamber by blocking them from the outside air, and the opening / closing means is the etching reaction chamber and the preparatory chamber. And between the preparatory chamber and the coating chamber can be switched between an open state and a closed state, and the sample transfer means transfers the sample between the etching reaction chamber and the preparatory chamber and between the preparatory chamber and the coating chamber. The device according to any one of claims 4 to 6, which is transportable. 8. A second silicon-based material on a first silicon-based material
Forming the material, A third silicon material so as to cover the second silicon material.
Forming a charge,The aluminum sample was applied to the surface of the sample obtained through the above steps.
A step of forming a um-based material, Obtained by going through the above stepsAluminum on the surface
Material exposedStep of storing sample in etching reaction chamber
When, The first gas is supplied to the etching reaction chamber to locally gas.
SwetchAlmost etches aluminum materials
WithoutExpose a portion of the second silicon-based material
Process, Discharging a first gas from the etching reaction chamber, After the first gas is discharged, the second reaction chamber is placed in the second reaction chamber.
Etching a recon material to produce first and third silicon materials
materialAnd aluminum-based materialsHardly etches
Gas etching of the second silicon-based material by supplying the second gas
A silicon-based structure characterized by having a step of
Manufacturing method. 9. A step of forming a second silicon-based material on the first silicon-based material, a step of forming a third silicon-based material so as to cover the second silicon-based material, and the above steps. A step of accommodating the sample obtained in step 1 into an etching reaction chamber, a step of supplying a first gas to the etching reaction chamber to locally perform gas etching to expose a part of the second silicon-based material, and the etching A step of discharging the first gas from the reaction chamber, and a second gas that etches the second silicon-based material and hardly etches the first and third silicon-based materials into the etching reaction chamber after the first gas is discharged. Gas for etching the second silicon-based material by supplying the gas , and the sample obtained through the above steps is treated with water vapor and an organic solvent.
A method for manufacturing a silicon-based structure, comprising a step of exposing to a mixed gas of an iodine compound .