JP2010214480A - Method of manufacturing microstructure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more easily remove residue generated when forming a structure by using a sacrifice layer made of organic resin. <P>SOLUTION: After removing the sacrifice layer 105, a substrate 101 formed with a lower electrode 141 and an upper electrode structure 171 is arranged in hydrogen fluoride gas for a prescribed time. For instance, if the substrate 101 is arranged in a sealable prescribed container and hydrogen fluoride gas is introduced into the container, the residue 111 stuck to the lower electrode 141 and the upper electrode structure 171, etc. formed on the substrate 101 can be exposed to hydrogen fluoride gas. As a result, hydrogen fluoride gas is acted on the residue 111 and the residue 111 is removed by etching. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a fine structure having a space between fine structures, such as a movable portion and a movable space.

  2. Description of the Related Art MEMS (Micro Electro Mechanical System) technology for producing a fine structure on a semiconductor substrate such as silicon or an insulating substrate such as glass has been developed. MEMS are being used in various fields such as various sensor fields, medical fields, and wireless communication fields. As an example, a MEMS switch having a fine switch structure manufactured by micromachine technology has excellent characteristics as a high-frequency switch (see Non-Patent Document 1).

  The MEMS switch includes a fixed electrode and a movable electrode. For example, the movable electrode is displaced by an electrostatic force, and the contact electrode fixed to the movable electrode and the fixed electrode are brought into contact with each other, thereby realizing an electrical switch operation. is there. In such a switch, it is important that the contact portion is a good contact. For example, when each electrode is made of a metal material, it is required that the metal surface be exposed on the surface of each electrode and that the contact resistance be small.

  A microstructure having a space between the electrode structures as described above is generally manufactured using a sacrificial layer. For example, a sacrificial layer is formed on the lower electrode, an upper electrode is formed on the sacrificial layer, and then the sacrificial layer is selectively removed. As a result, two electrode structures that are spaced apart from each other can be formed. As a material for the sacrificial layer, an organic resin is generally used. An organic resin can be formed at a low temperature and can be easily patterned. Therefore, if an organic resin is used for the sacrificial layer, for example, a microstructure can be manufactured at low cost on a CMOS-LSI without causing deterioration of LSI characteristics due to heat.

  By the way, as described above, the sacrificial layer is removed. Methods for removing the sacrificial layer of the organic resin include ashing using oxygen plasma (see Non-Patent Document 2) and ashing by heating the sacrificial layer and exposing it to an ozone atmosphere (see Patent Document 1). However, these methods have a problem that polymer films, fine particles, and the like become residues on the surface of the electrode and hinder the operation of the fine structure. In addition, the residue after ashing mentioned above originates in the adhesion | attachment adjuvant added mainly in order to improve the adhesiveness of organic resin and a board | substrate.

  As a method of removing such a residue after ashing, a method of removing the residue by washing by a wet process has been proposed. By cleaning the electrode surface by wet treatment, the residue is removed and a clean surface can be obtained. However, in this method, in the case of an electrode structure with a fine dimension, problems such as the electrodes sticking to each other in the drying process after the wet treatment or the like are broken due to the surface tension of the solution used in the wet treatment (non-patent). Reference 3).

  Here, in order to solve the problem of surface tension in the liquid treatment, a method of drying using a supercritical fluid after washing by a wet treatment has been proposed (see Non-Patent Document 3). However, in a process using a supercritical fluid, first, a special cleaning device that can withstand high pressure is required. In addition, it is necessary to repeat the processes such as pressurization, heating, decompression, and replacement a plurality of times. As described above, in the process using the supercritical fluid, the application is not easy, and the cleaning process requires a lot of time, so it is not easy to reduce the manufacturing process and cope with mass production ( Patent Document 2).

JP 2002-219695 A JP 2001-176837 A

G.M.Rebeiz and J.B.Muldavin, “RF MEMS switches and switch circuits”, IEEE Microwave Magazine, Vol.2, No.4, pp.59-70, Dec.2001. D. Hah, E. Yoon, and S. Hong, "A low-voltage actuated micromachined microwave switch using torsion springs and leverge", IEEE Trans. Microwave Theory and Techniques, Vol. 48, No. 12, pp. 2540-2545 , Dec. 2000. Tsuji, Kuniyasu, Hattori, “Limits of wet cleaning in high-aspect-ratio fine structures and pattern destruction-free cleaning technology”, IEICE Technical Report, SDM 2003-172, pp. 15-20, October 2003.

  As described above, conventionally, when a desired structure is manufactured using a sacrificial layer of an organic resin, such as manufacturing a fine structure having a movable part such as MEMS, the sacrificial layer is removed. There was a problem that the residue was not easy to remove.

  The present invention has been made to solve the above-described problems, and makes it possible to more easily remove residues generated when a structure is formed using a sacrificial layer made of an organic resin. For the purpose.

  The method for manufacturing a microstructure according to the present invention includes a first step of forming a structure using a sacrificial layer made of an organic resin on a substrate, and a second step of removing the sacrificial layer using active oxygen. And a third step of exposing the substrate to an atmosphere containing hydrogen fluoride gas. For example, in the first step, after forming the sacrificial layer, a structure may be formed on the sacrificial layer.

  In the method for manufacturing a fine structure, in the case where a step of forming a structure made of a silicon compound on a substrate is included before the third step, the processing temperature is preferably set to 40 ° C. or higher in the third step. In this case, the partial pressure of the hydrogen fluoride gas is preferably 10 kPa or more in the third step. Further, after the third step, a fourth step of exposing the substrate to an atmosphere containing active oxygen may be provided.

  As described above, according to the present invention, after removing the sacrificial layer using active oxygen, the substrate is exposed to an atmosphere containing hydrogen fluoride gas, so the sacrificial layer made of an organic resin is used, An excellent effect is obtained in that a residue generated when manufacturing a microstructure having a flexible structure that is spaced apart from the substrate can be more easily removed.

It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the plane in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 1 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is process drawing which shows the cross-sectional state in each process for demonstrating the manufacturing method in Embodiment 2 of this invention. It is a correlation diagram which shows the relationship between the etching rate by the hydrogen fluoride gas of silicon oxide, and substrate temperature. It is sectional drawing which shows typically the structure of the fine structure manufactured by Embodiment 2 of this invention. It is sectional drawing which shows typically the state in the middle of manufacture of the microstructure which can apply this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Embodiment 1]
First, the first embodiment of the present invention will be described. First, as shown in FIG. 1A, a seed layer 102 necessary for forming a metal film by plating is formed on a substrate 101 made of, for example, silicon. For example, a titanium layer and a gold layer may be stacked in this order by a sputtering method, an evaporation method, or the like, and these stacked films may be used as the seed layer 102. At this time, the thickness of the titanium layer may be about 0.1 μm, and the thickness of the gold layer may be about 0.1 μm.

  Next, as shown in FIG. 1B, first, a resist pattern 103 having an opening 103 a is formed on the seed layer 102. For example, a well-known photoresist material is applied on the seed layer to form a resist film. Next, the resist pattern 103 can be formed by patterning the resist film by a known photolithography technique using a photomask having a pattern corresponding to the opening 103a. The film thickness of the resist pattern 103 is about 1 μm.

  Next, the metal pattern 104 is formed by depositing gold by electrolytic plating on the seed layer 102 exposed in the opening 103a. The metal pattern 104 may be about 0.3 μm thick. The metal pattern 104 constitutes a part of the lower electrode described later. After the metal pattern 104 is thus formed, the resist pattern 103 is removed.

  Next, the seed layer 102 is selectively removed by etching using the metal pattern 104 as a mask, so that the lower electrode 141 is formed on the substrate 101 as shown in FIG. 1C. In etching the seed layer 102 around the metal pattern 104, first, the upper gold layer can be removed by wet etching using an etchant composed of iodine, ammonium iodide, water, and ethanol. In this etching, a part of the metal pattern 104 is also etched. The lower titanium layer can be removed by wet etching using an aqueous hydrogen fluoride solution.

  Next, as shown in FIG. 1D, a sacrificial layer 105 made of an organic resin is formed on the substrate 101 so as to cover the lower electrode 141, and an opening 105 a is formed in the sacrificial layer 105. For example, a photosensitive organic resin composed of PBO (polybenzoxazole) is applied onto the substrate 101 to form a coating film. Next, the sacrificial layer 105 having the opening 105a can be formed by patterning the formed coating film by a known lithography technique. In the patterning process of the sacrificial layer 105, a prebaking process at 120 ° C. is performed on the coating film for about 4 minutes as a pre-process. Further, after the patterning, a heat treatment at about 310 ° C. is performed and cured. In addition, as an organic resin used for the sacrificial layer 105, for example, CRC8300 manufactured by Sumitomo Bakelite may be used.

  Next, as shown in FIG. 1E, first, a seed layer 106 is formed on the sacrificial layer 105 including the inside of the opening 105a. Further, a metal pattern 107 is formed from a part of the opening 105a (FIG. 1D) to a region corresponding to the upper part of the lower electrode 141. Note that an opening 105 b is formed on one end side of the metal pattern 107. As shown in the cross-sectional view of FIG. 1F, the metal pattern 107 includes a support portion 108, a connection portion 109, and portions that become the upper electrode 110. The opening 105b is adjacent to the support portion 108. FIG. 1E shows a cross section taken along line ee ′ of FIG. 1F.

  Here, the seed layer 106 may be formed in the same manner as the seed layer 102 described above. Similarly to the metal pattern 104 described above, the metal pattern 107 is a resist pattern in which a desired region is opened, and gold is selectively plated on the seed layer 106 exposed in the opening. What is necessary is just to form. Even in this case, the film thickness of the resist pattern may be about 1 μm. The plating thickness of the metal pattern 107 may be about 0.3 μm.

  Next, the seed layer 106 is selectively removed by etching using the metal pattern 107 as a mask to form an upper electrode structure 171 in which the upper electrode 110 is disposed to face the upper side of the lower electrode 141 as shown in FIG. 1G. State. The upper electrode structure 171 includes a support portion 108 that is connected to the substrate 101, and a connecting portion 109 that connects the support portion 108 and the upper electrode 110. The etching of the seed layer 106 is the same as the etching of the seed layer 102 described above.

  Next, the sacrificial layer 105 is removed by, for example, ashing using oxygen plasma or an ozone atmosphere, so that the lower electrode 141 and the upper electrode 110 are separated from each other as shown in FIG. 1H. Here, in the removal using the active oxygen of the sacrificial layer 105 which is an organic resin as described above, a residue 111 is formed in a region where the sacrificial layer 105 is in contact. In such an ashing process, it is not easy to completely remove the organic resin, and a residue 111 is formed from a portion that remains unetched or a tracer generated by redeposition. The upper electrode structure 171 is a microstructure that displaces the upper electrode 110 with respect to the lower electrode 141, for example, when the connecting portion 109 is deformed (bent). However, the residue 111 hinders the above-described operation of the upper electrode structure 171.

  The residue 111 is derived from an auxiliary agent added to the organic resin in order to improve the adhesion of the sacrificial layer 105 to the substrate, and is mainly composed of silicon suboxide. For this reason, it is not easy to remove completely by the treatment using active oxygen as described above. On the other hand, the residue 111 can be removed with hydrogen fluoride gas. Therefore, after removing the sacrificial layer 105 as described above, the substrate 101 on which the lower electrode 141 and the upper electrode structure 171 are formed is placed in hydrogen fluoride gas for a predetermined time.

  For example, if the substrate 101 is placed in a predetermined container that can be sealed and hydrogen fluoride gas is introduced into the container, the substrate 101 adheres to the lower electrode 141 and the upper electrode structure 171 formed on the substrate 101. The remaining residue 111 can be exposed to hydrogen fluoride gas. As a result, hydrogen fluoride is allowed to act on the residue 111 and the residue 111 is removed by etching, so that the lower electrode 141 and the upper electrode structure are formed on the substrate 101 without any residue as shown in FIG. 1I. 171 can be formed.

  As described above, in this embodiment, the sacrificial layer made of an organic resin is removed by dry etching, and the residue formed on the electrode surface after the sacrificial layer is further removed is dry-etched using hydrogen fluoride gas. Remove with. Thus, according to the present embodiment, for example, a movable structure can be formed by two electrode structures, and the surface of the formed electrode structure can be sufficiently cleaned. For this reason, problems such as sticking of electrodes due to the residue do not occur, and a minute movable structure that does not impede driving by the residue can be manufactured. Moreover, according to this Embodiment, the residue is removed, without performing the liquid process from which surface tension becomes a problem. For this reason, damage such as fine pattern deformation or fixation due to surface tension does not occur.

  Note that after the treatment with hydrogen fluoride gas as described above, an ashing treatment may be performed in which the substrate is exposed to an atmosphere using active oxygen such as ozone gas or oxygen gas plasma. When a residue containing carbon remains on the surface of a structure such as an electrode after the treatment with hydrogen fluoride gas, the residue can be removed by an ashing treatment using active oxygen.

[Embodiment 2]
Next, a second embodiment of the present invention will be described. First, as shown in FIG. 2A, a seed layer 202 necessary for forming a metal film by plating is formed on a substrate 201 made of, for example, silicon. For example, a titanium layer and a gold layer may be stacked in this order by a sputtering method, a vapor deposition method, or the like, and these stacked films may be used as the seed layer 202. At this time, the thickness of the titanium layer may be about 0.1 μm, and the thickness of the gold layer may be about 0.1 μm.

  Next, as shown in FIG. 2B, first, a resist pattern 203 having an opening 203 a is formed on the seed layer 202. For example, a well-known photoresist material is applied on the seed layer to form a resist film. Next, the resist pattern 203 can be formed by patterning the resist film by a known photolithography technique using a photomask having a pattern corresponding to the opening 203a. The film thickness of the resist pattern 203 is about 1 μm.

  Next, a metal pattern 204 is formed by depositing gold on the seed layer 202 exposed in the opening 203a by electrolytic plating. The metal pattern 204 may have a thickness of about 0.3 μm. The metal pattern 204 constitutes a part of the lower electrode described later. After the metal pattern 204 is thus formed, the resist pattern 203 is removed.

  Next, the seed layer 202 is selectively removed by etching using the metal pattern 204 as a mask, so that a lower electrode (first electrode) 241 is formed on the substrate 201 as shown in FIG. 2C. In the etching of the seed layer 202 around the metal pattern 204, first, the upper gold layer can be removed by wet etching using an etchant composed of iodine, ammonium iodide, water, and ethanol. In this etching, part of the metal pattern 204 is also etched. The lower titanium layer can be removed by wet etching using an aqueous hydrogen fluoride solution.

  Next, as illustrated in FIG. 2D, an insulating film 241 a is formed on the lower electrode 241. For example, the insulating film 241a can be formed on the lower electrode 241 by depositing silicon oxide to form a silicon oxide film and patterning the silicon oxide film by a known photolithography technique and etching technique. The insulating film 241a may be formed with a film thickness of about 0.1 μm, for example.

  Next, as shown in FIG. 2E, a sacrificial layer 205 made of an organic resin is formed on the substrate 201 so as to cover the lower electrode 241 on which the insulating film 241a is formed, and an opening 205a is formed in the sacrificial layer 205. Form. For example, a photosensitive organic resin composed of PBO is applied onto the substrate 201 to form a coating film. Next, the sacrificial layer 205 having the opening 205a can be formed by patterning the formed coating film by a known lithography technique.

  In the patterning process of the sacrificial layer 205, a prebaking process at 120 ° C. is performed on the coating film for about 4 minutes as a pre-process. Further, after the patterning, a heat treatment at about 310 ° C. is performed and cured. As an organic resin used for the sacrificial layer 205, for example, CRC8300 manufactured by Sumitomo Bakelite may be used.

  Next, as shown in FIG. 2F, first, a seed layer 206 is formed on the sacrificial layer 205 including the inside of the opening 205a. Further, a metal pattern 207 is formed over a region corresponding to the upper portion of the lower electrode 241 from a part of the opening 205a (FIG. 2F). Note that an opening 205 b is formed on one end side of the metal pattern 207. Similarly to the metal pattern 107 in the first embodiment described above, the metal pattern 207 includes a portion that becomes the support portion 208, the connecting portion 209, and the upper electrode 210. The opening 205b is adjacent to the support 208.

  Here, the seed layer 206 may be formed in the same manner as the seed layer 202 described above. Similarly to the metal pattern 204 described above, the metal pattern 207 is a resist pattern in which a desired region is opened, and gold is selectively plated on the seed layer 206 exposed in the opening. What is necessary is just to form. Even in this case, the film thickness of the resist pattern may be about 1 μm. Further, the plating thickness of the metal pattern 207 may be about 0.3 μm.

  Next, the seed layer 206 is selectively removed by etching using the metal pattern 207 as a mask, thereby forming an upper electrode structure 271 in which the upper electrode 210 is disposed to face the lower electrode 241 as shown in FIG. 2G. State. The upper electrode structure 271 includes a support portion 208 that is connected to the substrate 201 and a connecting portion 209 that connects the support portion 208 and the upper electrode 210. The etching of the seed layer 206 is the same as the etching of the seed layer 202 described above.

  Next, the sacrificial layer 205 is removed by, for example, ashing using oxygen plasma or an ozone atmosphere, so that the lower electrode 241 and the upper electrode 210 are separated from each other as shown in FIG. 2H. Here, when the sacrificial layer 205 which is an organic resin as described above is removed using active oxygen, a residue 211 is formed in a region where the sacrificial layer 205 is in contact. In such an ashing process, it is not easy to completely remove the organic resin, and a residue 211 is formed from a portion that remains unetched or a trace element generated by reattachment. The upper electrode structure 271 is a microstructure that displaces the upper electrode 210 with respect to the lower electrode 241 when the connecting portion 209 is deformed (bends), for example. However, the residue 211 hinders the above-described operation of the upper electrode structure 271.

  The residue 211 is derived from an auxiliary agent added to the organic resin in order to improve the adhesion of the sacrificial layer 205 to the substrate, and is mainly composed of silicon suboxide. For this reason, it is not easy to remove completely by the treatment using active oxygen as described above. On the other hand, the residue 211 can be removed with hydrogen fluoride gas. By the way, in this embodiment mode, an insulating film (a structure made of a silicon compound) 241 a is provided on the lower electrode 241. The insulating film 241a made of silicon oxide is etched to some extent by hydrogen fluoride gas. Therefore, in order to remove the residue 211 using hydrogen fluoride gas, it is important that the insulating film 241a is not removed by the hydrogen fluoride gas.

  Here, the inventors' research has found that the etching rate of the residue 211 and the silicon oxide can be controlled by controlling the processing temperature and the partial pressure of the hydrogen fluoride gas when using hydrogen fluoride gas.

  First, as shown in FIG. 3, it has been found that the etching rate of silicon oxide by hydrogen fluoride gas decreases as the processing temperature increases. FIG. 3 shows the substrate temperature dependence of the etching rate of the silicon thermal oxide film formed on the silicon substrate by the hydrogen fluoride gas. The temperature of the silicon substrate is changed to 25 ° C., 40 ° C., and 70 ° C., and the silicon thermal oxide film on the surface of the substrate is etched with hydrogen fluoride gas having a saturated vapor pressure at each temperature. As a result, the etch rate of the silicon thermal oxide film is 180 nm / min or more at the substrate temperature condition of 25 ° C., but rapidly decreases when the temperature exceeds 40 ° C., and decreases to 3.5 nm / min at the 70 ° C. condition. .

  On the other hand, a photosensitive organic resin film is formed on a silicon substrate, and this is ashed to form a residue. The substrate is heated to 70 ° C. and exposed to hydrogen fluoride gas having a saturated vapor pressure. In this treatment, a residue having a thickness of 160 nm can be removed within 1 minute. Accordingly, the etching selectivity between the residue and silicon oxide can be increased by setting the processing temperature to 40 ° C. or higher, particularly 70 ° C., such as heating the substrate. It is important that the processing temperature is lower than the heat resistance temperature of the microstructure manufactured.

  It was also confirmed that the etching rate of the residue increased with respect to silicon oxide by setting the partial pressure of hydrogen fluoride gas to 10 kPa or more. Therefore, the selective ratio between the residue and silicon oxide can be increased by setting the partial pressure of hydrogen fluoride gas to 10 kPa or more. As a matter of course, the pressure (partial pressure) of hydrogen fluoride gas in this treatment is the maximum saturated vapor pressure of hydrogen fluoride gas at the treatment temperature.

  Therefore, in order to remove the formed residue 211 after removing the sacrificial layer 205 as described above, the substrate 201 on which the lower electrode 241 and the upper electrode structure 271 are formed is changed to a substrate temperature of 70 ° C., for example. And may be placed in hydrogen fluoride gas having a partial pressure of 10 kPa or more for a predetermined time. In addition, about temperature conditions and partial pressure conditions, you may make it correspond respectively, and you may combine these two. By removing the residue 211 by etching using such a hydrogen fluoride gas treatment, as shown in FIG. 2I, the lower electrode 241 in which the insulating film 241a is formed on the substrate 201 without any residue. And the upper electrode structure 271 can be formed.

  Although the case where the insulating film 241a is made of silicon oxide has been described above, the present invention is not limited to this. In the case where a structure formed of a material that is etched by hydrogen fluoride gas, such as a silicon compound such as silicon oxide or silicon nitride, is formed before the sacrifice layer is removed, the structure may be the same as described above.

  Also in this embodiment, after the treatment with hydrogen fluoride gas as described above, an ashing treatment may be performed in which the substrate is exposed to an active oxygen atmosphere such as plasma of ozone gas or oxygen gas. When a residue containing carbon remains on the surface of a structure such as an electrode after the treatment with hydrogen fluoride gas, the residue can be removed by an ashing treatment using active oxygen.

  By the way, by forming the insulating film 241a on the lower electrode 241, as shown in FIG. 4, when the upper electrode 210 is displaced, a short circuit due to contact between the lower electrode 241 and the upper electrode 210 is prevented. be able to. The insulating film 241a prevents the lower electrode 241 and the upper electrode 210 from coming into direct contact.

  In the above-described embodiment, the support portion, the connecting portion, and the upper electrode are integrally formed by plating, but the present invention is not limited to this. For example, as shown in FIG. 5, a support portion 503 is formed on a substrate 501 together with the lower electrode 502, and in this state, a sacrificial layer 504 is formed by embedding the lower electrode 502 and exposing the upper surface of the support portion 503. Thereafter, the upper electrode 505 may be formed on the sacrificial layer 504, and in addition, the beam portion 506 connected to the support portion 503 and the upper electrode 505 may be formed. In this manner, the support portion 503, the upper electrode 505, and the beam portion 506 may be formed individually. In addition, the support part 503 and the beam part 506 may be comprised from the metal, and may be comprised from insulators, such as a silicon oxide and a silicon nitride.

  As described above, according to the present invention, a sacrificial layer made of an organic resin is used on a substrate, such as manufacturing a microstructure having two structures (electrodes) that are spaced apart from each other in the vertical direction. Thus, when the structure is formed, residues generated after removing the sacrificial layer can be more easily removed.

  When a structure is formed using a sacrificial layer made of an organic resin including a resist pattern used in a lithography technique, a residue after the sacrificial layer is removed becomes a problem. For example, in the case of the movable electrode structure described above, the operation of the upper electrode is hindered. In addition, in an LSI multilayer wiring structure or the like, if a residue remains after a wiring structure or the like is formed using a resist pattern, it greatly affects the next wiring formation process. Further, if a residue or the like remains after forming a micro flow path using a resist pattern, there arises a problem that the desired performance as the flow path cannot be exhibited.

  Thus, when forming a structure using a sacrificial layer, the residue after removing the sacrificial layer becomes a serious problem. According to the present invention, this residue can be removed more easily without using a complicated process such as using a supercritical fluid or using a complicated apparatus. Furthermore, according to the present invention, it is possible to remove residues even when a silicon compound such as silicon oxide is provided.

  In addition, according to the present invention, for example, there is a space between two electrode structures such as a capacitive pressure sensor, an acceleration sensor, a variable capacitance element, a movable mirror structure, a vibrator, a mechanical filter, and a switch. Even in this fine structure, the same effect as the above-described embodiment can be obtained.

  DESCRIPTION OF SYMBOLS 101 ... Substrate 102 ... Seed layer 103 ... Resist pattern 103a ... Opening 104 ... Metal pattern 105 ... Sacrificial layer 105a ... Opening 105b ... Opening 106 ... Seed layer 107 ... Metal pattern 108 DESCRIPTION OF SYMBOLS ... Support part, 109 ... Connection part, 110 ... Upper electrode, 111 ... Residue, 141 ... Lower electrode, 171 ... Upper electrode structure.

Claims (5)

A first step of forming a structure using a sacrificial layer made of an organic resin on a substrate;
A second step of removing the sacrificial layer using active oxygen;
And a third step of exposing the substrate to an atmosphere containing hydrogen fluoride gas. In the manufacturing method of the fine structure according to claim 1,
In the first step, after the sacrifice layer is formed, the structure is formed on the sacrifice layer. In the manufacturing method of the fine structure according to claim 1 or 2,
Before the third step, a step of forming a structure made of a silicon compound on the substrate is included, and in the third step, a processing temperature is set to 40 ° C. or more. Method. In the manufacturing method of the fine structure according to claim 1 or 2,
Before the third step, a step of forming a structure made of a silicon compound on the substrate is included, and in the third step, the partial pressure of hydrogen fluoride gas is 10 kPa or more. Manufacturing method of structure. In the manufacturing method of the microstructure according to any one of claims 1 to 4,
After the third step, the method for manufacturing a microstructure includes a fourth step of exposing the substrate to an atmosphere containing active oxygen.

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