CN101212836A - Electret condenser microphone and manufacturing method thereof - Google Patents
Electret condenser microphone and manufacturing method thereof Download PDFInfo
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- CN101212836A CN101212836A CNA2007101860950A CN200710186095A CN101212836A CN 101212836 A CN101212836 A CN 101212836A CN A2007101860950 A CNA2007101860950 A CN A2007101860950A CN 200710186095 A CN200710186095 A CN 200710186095A CN 101212836 A CN101212836 A CN 101212836A
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- 239000003990 capacitor Substances 0.000 claims description 123
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- 238000000034 method Methods 0.000 claims description 73
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- 238000012545 processing Methods 0.000 claims description 57
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- 239000010703 silicon Substances 0.000 claims description 30
- 229910052710 silicon Inorganic materials 0.000 claims description 30
- FFUAGWLWBBFQJT-UHFFFAOYSA-N hexamethyldisilazane Chemical compound C[Si](C)(C)N[Si](C)(C)C FFUAGWLWBBFQJT-UHFFFAOYSA-N 0.000 claims description 28
- 238000006884 silylation reaction Methods 0.000 claims description 27
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- 238000007254 oxidation reaction Methods 0.000 claims description 14
- 238000009489 vacuum treatment Methods 0.000 claims description 14
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- DLFVBJFMPXGRIB-UHFFFAOYSA-N Acetamide Chemical compound CC(N)=O DLFVBJFMPXGRIB-UHFFFAOYSA-N 0.000 description 4
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
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- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 2
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- 238000012360 testing method Methods 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- PQDJYEQOELDLCP-UHFFFAOYSA-N trimethylsilane Chemical compound C[SiH](C)C PQDJYEQOELDLCP-UHFFFAOYSA-N 0.000 description 2
- SIOVKLKJSOKLIF-HJWRWDBZSA-N trimethylsilyl (1z)-n-trimethylsilylethanimidate Chemical compound C[Si](C)(C)OC(/C)=N\[Si](C)(C)C SIOVKLKJSOKLIF-HJWRWDBZSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 1
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- 125000003808 silyl group Chemical group [H][Si]([H])([H])[*] 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G7/00—Capacitors in which the capacitance is varied by non-mechanical means; Processes of their manufacture
- H01G7/02—Electrets, i.e. having a permanently-polarised dielectric
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
- Pressure Sensors (AREA)
Abstract
The invention discloses an Electret condenser microphone and manufacturing method thereof. In producing film 2 (lower electrode) of electret 4 and upper electrode 1 opposed to the film 2 with an air gap interposed, degasification is performed before water repellent finishing with respect to the inside of the air gap 3. The present invention has its object of definitely preventing leakage of the charges stored in an electret to outside in an electret condenser microphone.
Description
Technical field
The present invention relates to the manufacture method of a kind of sound equipment testing agency, particularly a kind of Micro Electro Mechanical System (MEMS:Micro Electro Mechanical Systems) formed electret capacitor microphone of technology and manufacture method thereof utilized.
Background technology
Electret capacitor microphone is the microminiature microphone with parallel plate capacitor, and its operation principle is, if the change of an electrode response sound press of capacitor and vibrating, the electrostatic capacitance of capacitor will change, and this variation finally is transformed to voltage signal.
Electret capacitor microphone has two types, a kind of is a plurality of parts to be fit together and the fit type electret capacitor microphone made, another kind of then be that to utilize semiconductor technology be the integrally formed type electret capacitor microphone that the MEMS technology is made whole microphone one.
Because the manufacturing of fit type electret capacitor microphone is simple, so this electret capacitor microphone is a main flow always.But because utilized coating technique, so all be restricted at the aspects such as raising of the process reliability of the reduction of for example stable on heating raising, miniaturization, cost and sticking part.Just because of this, the integrally formed type electret capacitor microphone that utilizes semiconductor technology that whole microphone is made one just begins to move towards practical.
Below, be elaborated with reference to one of 8 pairs of patent documentations of figure, 1 disclosed existing integrally formed type electret capacitor microphone example.
Fig. 8 is the cutaway view of disclosed integrally formed type electret capacitor microphone in the patent documentation 1.
As shown in Figure 8, on Semiconductor substrate 201, be formed with silicon oxide film 202, simultaneously, the zone (fringe region) of defined reserved remove Semiconductor substrate 201 and silicon oxide film 202 and form film zone 213.Here, film zone 213 is to vibrate the zone that obtains after the part removal of Semiconductor substrate 201 in order to guarantee vibrating membrane 212 described later to receive pressure from the outside.Silicon nitride film 203 is formed on the silicon oxide film 202 film zone 213 is covered.Be formed with a conducting film on silicon nitride film 203, this conducting film becomes bottom electrode 204 and lead-out wiring 215.On silicon nitride film 203, bottom electrode 204 and lead-out wiring 215, be formed with silicon oxide film 205 and silicon nitride film 206 in regular turn respectively.Here, in bottom electrode 204 and silicon oxide film 205, be formed with leakage sound hole 207.And silicon nitride film 203 and silicon nitride film 206 will be formed with that a part of bottom electrode 204 and the silicon oxide film 205 that leak sound hole 207 and be positioned at film zone 213 and be surrounded.
Remark additionally, constitute vibrating membrane 212 by the silicon nitride film 203 that is positioned at film zone 213, bottom electrode 204, silicon oxide film 205 and silicon nitride film 206.Silicon oxide film 205 is foil electrets that electric charge is accumulated.Above silicon nitride film 206, be formed with the fixedly film (top electrode) 210 that constitutes by the conducting film that is surrounded by silicon nitride film 214.At vibrating membrane 212 with fixedly be formed with space 209 between the film 210.The silicon nitride film 206 in 213 outsides, film zone with fixedly between the film 210 and at the silicon oxide film 202 in regional 213 outsides of film and fixedly be formed with silicon oxide film 208 between the film 210.Space 209 forms 213 coverings to major general's thin film region territory.The fixedly film 210 (perhaps covering the fixedly silicon nitride film 214 of film 210) that is arranged in 209 tops, space is formed with a plurality of acoustic holes 211.At silicon nitride film 214, fixedly form opening 216 in film 210 and the silicon oxide film 208 and allow the part of lead-out wiring 215 expose, in silicon nitride film 214, form opening 217 simultaneously and allow fixedly the part of film 210 expose.
Fig. 9 (a) is the figure of each operation that schematically shows the manufacture method of existing electret capacitor microphone to Fig. 9 (f), and the basic structure of this existing electret capacitor microphone is the same with the basic structure of the integrally formed type electret capacitor microphone shown in the patent documentation 1.Remark additionally, in Fig. 9 (f), represent the inscape identical, the part that repeats is just no longer done having illustrated with electret capacitor microphone shown in Figure 8 with same symbol at Fig. 9 (a).Simultaneously, for convenience of description, a part of inscape has been omitted diagram.
At first, shown in Fig. 9 (a), form silicon oxide film 202 at the surface and the back side of the Semiconductor substrate 201 that forms by silicon.Then, shown in Fig. 9 (b), on the silicon oxide film 202 of the surface of Semiconductor substrate 201 side, form silicon nitride film 203 in regular turn, become conducting film, silicon oxide film 205 and the silicon nitride film 206 of bottom electrode 204, simultaneously, form bottom electrode 204 by being used in combination photoetching and etching technique, leak sound hole 207 and vibrating membrane 212.
Afterwards, shown in Fig. 9 (c), the final sacrifice layer oxide-film 218 that is provided with space 209 that forms.
Then, shown in Fig. 9 (d), be used in combination film forming, photoetching and etching technique and on sacrifice layer oxide-film 218, form the fixedly film 210 that constitutes and have concaveconvex structure by the conducting film that is surrounded by silicon nitride film 214 (not shown)s.Afterwards, fixedly leaving acoustic hole 211 in the film 210.Afterwards, shown in Fig. 9 (e), be used in combination photoetching and etching technique and form from the back side one side of Semiconductor substrate 201 and pass the through hole 219 that this substrate arrives the silicon oxide film 202 of this substrate surface one side.
Then, shown in Fig. 9 (f), pass acoustic hole 211 a part of sacrifice layer oxide-film 218 wet etchings are come fixedly forming space 209 between film 210 and the vibrating membrane 212.At this moment, passing Lou, the silicon oxide film 202 of 207 pairs of Semiconductor substrate 201 surperficial sides of sound hole also carries out partially-etched.
So, just made integrally formed type electret capacitor microphone, its structure is such, plays the vibrating membrane 212 of the effect of bottom electrode and electret, that the fixedly film 210 that plays the effect of top electrode clips space 209 is opposed.
Yet, pass acoustic hole and be exposed at structure in the outer air because electret capacitor microphone has foil electret, so between the environment of the high temperature environment that wet, low temperature and low humidity, use under the situation of this electret capacitor microphone more, in other words, using under the poor environment of condensing water droplet under the situation of this electret capacitor microphone, the little inside, space of area of the opening that communicates with the tube outer air (acoustic hole and leakage sound hole) just becomes the poor environment of the water droplet that freeze-outs especially easily.The result is, vibrating membrane and fixedly film is owing to condensing water droplet is close together, and the electric charge that is accumulated in the electret just is easy to drain in the outer air, and this is a potential problem.
For addressing this problem, following solution has been proposed in patent documentation 2, the fit type electret capacitor microphone is put into to come in hexamethyldisilazane (HMDS:hexamethyldisilazane) gaseous environment that aquation is refused in inside, space and handle, prevent thus vibrating membrane and fixedly film owing to condensing water droplet is close together, thereby the electric charge that prevents to be accumulated in the electret drains in the outer air.
Below, with reference to the accompanying drawings, the manufacture method of the fit type electret capacitor microphone shown in the patent documentation 2 is described.Figure 10 (a) is the figure of each operation that shows the manufacture method of the existing electret capacitor microphone shown in the patent documentation 2 to Figure 10 (f).
Shown in Figure 10 (a), form silicon oxide film 302 at the surface and the back side of Semiconductor substrate 301.Then, shown in Figure 10 (b), be used in combination photoetching and etching technique and optionally remove the top of Semiconductor substrate 301 and the silicon oxide film 302 of substrate surface one side, become the pit of space 309 (with reference to Figure 10 (f)).
Afterwards, shown in Figure 10 (c), form silicon oxide film 302 once more on the surface of the Semiconductor substrate of exposing from this pit 301.Afterwards, shown in Figure 10 (d), be used in combination photoetching and etching technique and form the through hole 319 that passes the silicon oxide film 302 in the described pit of Semiconductor substrate 301 arrival from the back side one side of Semiconductor substrate 301.
Then, shown in Figure 10 (e), will be in electret capacitor microphone in the manufacture process and be put into to come in the HMDS gaseous environment that silicon oxide film 302 is refused aquation and handle (position of representing to have water repellency among the figure with symbol 322 (stain)).
At last, shown in Figure 10 (f), surface one side that vibrating membrane 312 is attached to Semiconductor substrate 301 is built described pit.Vibrating membrane 312 has the membrane structure that for example is formed with conducting film on the dielectric film resemble the silicon oxide film.So, Semiconductor substrate 301 just plays bottom electrode, and the described pit that is covered by vibrating membrane 312 becomes space 309, just can produce the fit type electret capacitor microphone that the silicon oxide film 302 that is arranged in the space 309 becomes electret.
" patent documentation 1 " day disclosure special permission communique spy opens the 2006-074102 communique
No. 4910840 specifications of " patent documentation 2 " United States Patent (USP)
Summary of the invention
The technical problem that-invention will solve-
Yet, even resemble put down in writing in the patent documentation 2 utilize the HMDS material that electret capacitor microphone is refused aquation to handle, can not prevent fully that the electric charge that is accumulated in electret from draining in the outer air, this is a problem.
The present invention makes for addressing the above problem just, and its purpose is: prevent reliably that in electret capacitor microphone the electric charge that is accumulated in electret from draining in the outer air.
-in order to the technical scheme of technical solution problem-
For reaching described purpose, drain to method in the outer air as the electric charge that also can prevent to be accumulated in electret under the environment of the water droplet that freeze-outs in meeting, this case inventor has at first expected following invention.
In other words, the manufacture method of first electret capacitor microphone involved in the present invention, be comprise first electrode that is provided with electret, accompanying between it and described first electrode space and with the manufacture method of the electret capacitor microphone of second electrode of described first electrode contraposition in, comprise following operation, operation a, to the processing that outgases of the inside in described space, and operation b, after described operation a, at least aquation is refused in the inside in described space and handle.
Manufacture method according to first electret capacitor microphone of the present invention, because before inside, space being refused the aquation processing, outgas processing, so remove after can handling gasifications such as the moisture will remain in space inwall etc., ethanol molecule by the degassing, and then refuse the aquation processing.So, handle because can carry out the aquation of refusing of inside, space reliably, so space inwall etc. have very strong water repellency.The result is, drains in the outer gas of tube even also can prevent the electric charge that is accumulated in electret under the poor environment of the water droplet that freeze-outs easily, thereby can make the reliability raising of electret capacitor microphone.
Preferably, in the manufacture method of first electret capacitor microphone of the present invention, in described operation b, under the hexamethyldisilazane gaseous environment, carry out heat treated.
So, because become moisture, ethanol etc. and be removed the only residual inside, space that the state of hydroxy is arranged handling by the degassing, hydroxy (correctly saying, is the hydrogen in the hydroxy) is by Si (CH
3)
3Base replaces, so space inwall etc. just have very strong water repellency.
Preferably, in the manufacture method of first electret capacitor microphone of the present invention, in described operation a, or only carry out vacuum treatment, or only carry out baking processing, or carry out vacuum treatment and these two kinds of processing of baking processing.
So, just can gasify reliably and remove remaining in moisture in the space, ethanol etc.
Remark additionally, in the manufacture method of first electret capacitor microphone of the present invention, the processing that both can outgas in same cavity is handled with refusing aquation, can outgas in different cavitys again and handle and refuse the aquation processing.
For the fit type electret capacitor microphone, as putting down in writing in the patent documentation 2, if electret capacitor microphone is put in the HMDS gaseous environment, then can make vibrating membrane and the fixedly water repellency raising of film, prevent vibrating membrane and fixedly film owing to the water droplet that freeze-outs is adjacent to together, thereby the electric charge that prevents to a certain extent to be accumulated in the electret drains in the outer air.But, in the manufacture process that causes the integrally formed type electret capacitor microphone that people pay attention in recent years, even intactly using in the patent documentation 2 the disclosed aquation of refusing handles, can not make vibrating membrane and fixedly any film in the film have sufficient water repellency, the result is to prevent vibrating membrane and the fixedly film phenomenon generation so together owing to the water droplet that freeze-outs is adjacent to.In other words, compare, in integrally formed type electret capacitor microphone, prevent to be accumulated in electric charge in the electret and drained to the difficulty that just becomes in the outer air more with the fit type electret capacitor microphone.
So this case invention people reaches following purpose to have carried out following research and inquirement.Purpose is exactly, in integrally formed type electret capacitor microphone, also make vibrating membrane and fixedly film both sides' water repellency improve, prevent vibrating membrane and fixedly film is owing to the water droplet that freeze-outs is adjacent to together, the electric charge that prevents from thus to be accumulated in the electret drains in the outer air.Particularly, this case inventor, in integrally formed type electret capacitor microphone and fit type electret capacitor microphone, refuse after aquation handles in order to find out, vibrating membrane and fixedly the water repellency of film but have the very reason of big-difference, to the disclosed aquation of refusing in the patent documentation 2 is handled the manufacture method of disclosed electret capacitor microphone in the situation be applied to the manufacture method of disclosed integrally formed type electret capacitor microphone in the patent documentation 1 and the patent documentation 2 and has been carried out detailed comparison.The result has obtained following opinion.
Figure 11 (a) and Figure 11 (b) handle under the situation in the manufacture method be applied to disclosed integrally formed type electret capacitor microphone in the patent documentation 1 figure that refuses the situation that aquation handles that carries out at the space inwall in order to explanation disclosed aquation of refusing in patent documentation 2.
Shown in Fig. 9 (f), in the manufacture process of integrally formed type electret capacitor microphone, it is fixedly to form space 209 between film 210 and the vibrating membrane 212 by wet etching sacrifice layer oxide-film 218 partly that an operation is arranged.At this moment, shown in Figure 11 (a), silicon nitride film 206 (being formed on above the vibrating membrane 212) and silicon nitride film 214 (be formed on fixing film 210 below, be provided with opening (acoustic hole 211)) near the existence of each film stops by Si (CH
3)
3The ethanol molecule that base replaces (CH for example
3OH), hydrone (H
2O) etc.And, can become Si (CH on the surface of silicon nitride film 206 and silicon nitride film 214 each film
3)
3The hydroxy of the replacement object of base is original just seldom.Therefore, shown in Figure 11 (b),, be present in the Si (CH on the surface of silicon nitride film 206 and silicon nitride film 214 each film even be put in the HMDS gaseous environment
3)
3The density of base is also very little.Such supposition can be made thus, promptly fixedly in vibrating membrane 212, all sufficient water repellency can not be obtained in the film 210.Remark additionally, hydroxy is by Si (CH under the HMDS gaseous environment
3)
3Base replaces and produces this fact of water repellency is that known being adjacent to property with the raising photoresistance is purpose technology (patent documentation 2).
Figure 12 (a) and Figure 12 (b) are the figure in order to the situation of refusing the aquation processing of carrying out at the space inwall in the manufacture method of disclosed electret capacitor microphone in the explanation patent documentation 2.
Arrive shown in Figure 10 (f) as Figure 10 (a), in the manufacture process of fit type electret capacitor microphone, because can becoming to fit behind the pit in space 309 again, first formation goes up vibrating membrane 312, so, shown in Figure 12 (a), near the silicon oxide film 302 that is fixed on substrate surface, exist hardly to stop by Si (CH
3)
3The ethanol molecule that base replaces (CH for example
3OH), hydrone (H
2O) etc.And, there is the abundant Si (CH that becomes on the surface of silicon oxide film 302
3)
3The hydroxy of the replacement object of base.Therefore, shown in Figure 12 (b),, then be present in the Si (CH on silicon oxide film 302 surfaces if be put in the HMDS gaseous environment
3)
3The density of base just becomes very high.Can make such supposition thus, promptly the surface energy at silicon oxide film 302 accesses sufficient water repellency.Remark additionally, can use the good material of water repellency to be formed on and refuse the vibrating membrane 312 that the aquation processing is fitted to substrate one side afterwards again, can prevent the generation of problem thus.
This case inventor has expected following invention according to above-mentioned opinion, and the electric charge that also can prevent to be accumulated in electret in a kind of integrally formed type electret capacitor microphone under the environment that is in the water droplet that can freeze-out drains to the method in the outer air.
In other words, the manufacture method of second electret capacitor microphone involved in the present invention, be to comprise: be provided with electret and first electrode that can vibrate, between it and described first electrode, accompany the space and with second electrode of described first electrode contraposition, and, the manufacture method of the integrally formed type electret capacitor microphone that is covered by silicon nitride film towards the position in described space at least in described first electrode and described second electrode surface separately is a prerequisite, this manufacture method comprises: operation a, to the processing that outgases of the inside in described space; Operation b, the surface oxidation to the described silicon nitride film of major general after described operation a forms silicon oxynitride film; And operation c, after described operation b, at least silylation (silyl group) is carried out on the surface of described silicon oxynitride film and replace processing.
Manufacture method according to second electret capacitor microphone of the present invention, aquation is handled that is the processing that outgases is before handled in silylation replacement (silanization) because in that the inside in space is refused, so can after gasifications such as the moisture that utilizes the degassing to handle to remain in the space, ethanol, remove, refuse the aquation processing afterwards again.And, because carrying out the surface oxidation that covers the silicon nitride film of first electrode and second electrode respectively being formed silicon oxynitride film, so can make the hydroxy that can become the replacement of silylation object very abundant before silylation replaces.So, replace because can be reliably the inwall in space be carried out silylation, so just have very strong water repellency in first electrode and second electrode surface separately towards the position in space etc.Therefore, even first electrode (vibrating membrane) that also can prevent to be provided with electret under the poor environment of the water droplet that freeze-outs easily and second electrode (fixedly film) are owing to the water droplet that freeze-outs is close together, thereby can prevent to be accumulated in the electric charge of electret owing to the water droplet that freeze-outs drains in the outer gas.The result is that the reliability of electret capacitor microphone is improved.
Preferably, in the manufacture method of second electret capacitor microphone of the present invention, in described operation b, carry out plasma oxidation and handle.
So, even, also can reliably the surface oxidation that covers the silicon nitride film of first electrode and second electrode respectively be formed silicon oxynitride film in the little inside, space of area of the opening that communicates with the tube outer air (acoustic hole and leakage sound hole).And, replace plasma oxidation if for example utilize in the oxygen-containing gas environment for a long time baking processing (thermal oxidation) to wait, also can receive same effect.
Preferably, in the manufacture method of second electret capacitor microphone of the present invention, in described operation c, under the hexamethyldisilazane gaseous environment, carry out heat treated.
So, because become moisture, ethanol etc. and be removed the only residual inside, space that the state of hydroxy is arranged handling by the degassing, can be by Si (CH
3)
3Base replaces hydroxy (correctly saying, is the hydrogen in the hydroxy), so space inwall etc. just have very strong water repellency.And, because HMDS is a general silylating reagent cheap, that get easily, replace so can carry out silylation at low cost.
Preferably, in the manufacture method of second electret capacitor microphone of the present invention, in described operation a, or only carry out vacuum treatment, or only carry out baking processing, or carry out vacuum treatment and these two kinds of processing of baking processing.
So, just can gasify reliably and remove remaining in moisture in the space, ethanol etc.
Electret capacitor microphone involved in the present invention, to comprise: be provided with electret and first electrode that can vibrate, between it and described first electrode, accompany the space and with the integrally formed type electret capacitor microphone of second electrode of described first electrode contraposition be prerequisite, in described first electrode and described second electrode surface separately at least the position towards described space covered with the terminal silicon oxynitride film of silylation (containing three substituted silane bases).
In other words, because electret capacitor microphone involved in the present invention is the electret capacitor microphone that utilizes the manufacture method of aforementioned second electret capacitor microphone of the present invention to obtain, position towards the space in first electrode and second electrode surface separately is that terminal silicon oxynitride film covers with the silylation, just has very strong water repellency so be provided with first electrode (vibrating membrane) of electret respectively with second electrode (fixedly film).Therefore, even under the poor environment of the water droplet that freeze-outs easily, also can prevent vibrating membrane and fixedly film can prevent thus that owing to the water droplet that freeze-outs is adjacent to together the electric charge that is accumulated in the electret from draining in the outer air.The result is that the reliability of electret capacitor microphone is improved.
Preferably, in electret capacitor microphone of the present invention, described silylation is Si (CH
3)
3Base.
So, the general silylating reagent of just can use cheapness, getting easily is that HMDS makes electret capacitor microphone of the present invention.Therefore can suppress manufacturing cost.And, even with for example N-trimethyl silane yl acetamide (TMSA:(N-Trimethylsilylacetamide), N, (BSA:(N, O-Bis (trimethylsilyl)-acetamide) wait other silylating reagent to wait to receive same effect to the two trimethyl silane yl acetamides of O-.
The effect of-invention-
According to the present invention, because refuse the aquation processing again after utilizing the degassing to handle to remove the moisture that remains in, ethanol etc., so can make the inwall etc. in space have very strong water repellency in the space in.Therefore, even under the poor environment of easy condensing water droplet, can prevent that also the electric charge that is accumulated in the electret from draining in the outer air, thereby the reliability of electret capacitor microphone is improved.
According to the present invention, in the manufacture process of integrally formed type electret capacitor microphone, before refusing aquation processing that is silylation replacement, the surface oxidation that covers the silicon nitride film of first electrode and second electrode is respectively formed silicon oxynitride film, so can make the hydroxy that becomes the replacement of silylation object very abundant.So, replace because can be reliably the inwall in space be carried out silylation, so just have very strong water repellency in first electrode and second electrode surface separately towards the position in space etc.Therefore, even in the integrally formed type electret capacitor microphone in being in the poor environment of easy frosting, also can prevent to be accumulated in the electric charge of electret owing to frosting drains in the outer gas of tube.The result is that the reliability of integrally formed type electret capacitor microphone is improved.
The simple declaration of accompanying drawing
Fig. 1 (a) is the cutaway view of each operation of the manufacture method of the electret capacitor microphone that shows that first embodiment of the invention is related to Fig. 1 (h).
Fig. 2 (a) and Fig. 2 (b) are before the degassing that is presented at the manufacture method of the related electret capacitor microphone of first embodiment of the invention is handled and the figure of one of degassing temperature programmed desorption analysis result after handling example.
Fig. 3 (a) and Fig. 3 (b) are used in combination the degassing in the manufacture method of the related electret capacitor microphone of first embodiment of the invention in order to explanation to handle and refuse the figure that refuses hydration mechanism that aquation is handled.
Fig. 4 be in order in the explanation manufacture method of existing electret capacitor microphone as a comparative example refuse hydration mechanism figure.
Fig. 5 is the cutaway view of the related integrally formed type electret capacitor microphone of second embodiment of the invention.
Fig. 6 (a) is the cutaway view of each operation in the manufacture method of the integrally formed type electret capacitor microphone that shows that second embodiment of the invention is related to Fig. 6 (g).
Fig. 7 (a) is the figure that refuses the aquation processing that carries out at the space inwall in order in the manufacture method of the related integrally formed type electret capacitor microphone of explanation second embodiment of the invention to Fig. 7 (d), Fig. 7 (a) shows the aquation processing beginning state before of refusing, Fig. 7 (b) shows the state after the degassing is handled, Fig. 7 (c) shows the state behind the plasma oxidation, and Fig. 7 (d) shows the state after Si (CH3) 3 bases replace.
Fig. 8 is the cutaway view of the integrally formed type electret capacitor microphone shown in the patent documentation 1.
Fig. 9 (a) is the cutaway view of each operation in the manufacture method of the electret capacitor microphone that shows that basic structure is identical with disclosed integrally formed type electret capacitor microphone in the patent documentation 1 to Fig. 9 (f).
Figure 10 (a) is the cutaway view that shows each operation in the manufacture method of disclosed fit type electret capacitor microphone in the patent documentation 2 to Figure 10 (f).
Figure 11 (a) and Figure 11 (b) handle under the situation in the manufacture method that is applied to disclosed integrally formed type electret capacitor microphone in the patent documentation 1 figure that refuses the situation that aquation handles that carries out at the space inwall in order to explanation disclosed aquation of refusing in patent documentation 2, what Figure 11 (a) showed is initial condition, and that Figure 11 (b) shows is Si (CH
3)
3State after base replaces.
Figure 12 (a) and Figure 12 (b) are the figure in order to the situation of refusing the aquation processing of carrying out at the space inwall in the manufacture method of disclosed electret capacitor microphone in the explanation patent documentation 2, what Figure 12 (a) showed is initial condition, Figure 12 (b) demonstration having carried out Si (CH
3)
3State after base replaces.
Embodiment
(first embodiment)
Below, with reference to the accompanying drawings, the manufacture method of the related electret capacitor microphone of first embodiment of the invention is described.
Fig. 1 (a) is the cutaway view of each operation of the manufacture method of the electret capacitor microphone that shows that this embodiment is related to Fig. 1 (h).
At first, shown in Fig. 1 (a), form the dielectric film 14 that for example constitutes by silicon oxide film at the surface and the back side of the Semiconductor substrate 13 that forms by for example silicon.Then, shown in Fig. 1 (b), on the dielectric film 14 of the surface of Semiconductor substrate 13 side, form after the film 2, in this this film 2, form again and leak sound hole 23.This film 2 by the dielectric film that will become electret at the conducting film superimposed layer that will become bottom electrode after and constitute.
Then, shown in Fig. 1 (c), on film 2, form after the expendable film 20 that constitutes by for example silicon oxide film, shown in Fig. 1 (d), on expendable film 20, form top electrode 1 for another example.Afterwards, shown in Fig. 1 (e), after combination utilizes photoetching and etching technique to come to form acoustic hole 25 in top electrode 1, shown in Fig. 1 (f), combination utilizes photoetching and etching technique to form from the back side one side of Semiconductor substrate 13 and passes the through hole 8 that Semiconductor substrate 13 arrives the dielectric film 14 of substrate surface one side.
Then, shown in Fig. 1 (g), by acoustic hole 25 with expendable film 20 partly wet etching come between top electrode 1 and film 2 (bottom electrode), to form space 3.At this moment, pass the dielectric film 14 of sound hole 23 Semiconductor substrate 13 surperficial sides Lou also by partly etching.
At last, shown in Fig. 1 (h), utilized the aquation of refusing of HMDS for example to handle (refuse position that aquation handles with symbol 5 (stain) expression) to the Semiconductor substrate 13 that contains space 3.So, a part of just having made to be arranged in the film 2 in the space 3 is that dielectric film is the electret capacitor microphone of electret 4.
This embodiment is characterised in that, carry out described refuse aquation handle before to the processing that outgases of the inside in space 3.The degassing is handled, and is the combination that Semiconductor substrate 13 is exposed the vacuum treatment more than 1 hour under the pressure below the 25Pa for example and Semiconductor substrate 13 is exposed the baking processing more than 24 hours under the temperature more than 300 ℃ for example.Remark additionally, the condition that the degassing is handled is not occur the peak value of moisture, ethanol etc. in the temperature programmed desorption analysis result.Fig. 2 (a) shows the degassing of this embodiment and handles one of temperature programmed desorption analysis result before example, and Fig. 2 (b) shows the degassing of this embodiment and handles one of temperature programmed desorption analysis result afterwards example.By Fig. 2 (a) and Fig. 2 (b) as can be known, the peak value of being seen before the degassing is handled has disappeared after degassing processing.
Fig. 3 (a) and Fig. 3 (b) are used in combination the degassing in the manufacture method of electret capacitor microphone of this embodiment in order to explanation to handle and refuse the figure that refuses hydration mechanism that aquation is handled.Remark additionally, in Fig. 3 (a) and Fig. 3 (b), represent the inwall in space with square frame.
Handle if carry out the degassing of this embodiment, then shown in Fig. 3 (a), remain in the ethanol molecule (CH for example of space inwall etc.
3OH), hydrone (H
2O) etc. be removed after the gasification.The result is to become the only residual state of hydroxy down in the space.
Next, if used HMDS (in other words, Si (CH
3)
3-NH-Si (CH
3)
3) the aquation of refusing handle, then shown in Fig. 3 (b), the hydroxy in the space (correctly saying, is the hydrogen in the hydroxy) is by Si (CH
3)
3Base replaces.The result is that the inwall in space etc. has very strong water repellency.
Fig. 4 be in order to explanation as a comparative example in the manufacture method of only refusing the existing electret capacitor microphone that aquation handles in the space refuse hydration mechanism figure.Remark additionally, represent the inwall in space among Fig. 4 with square frame.
As existing, only utilizing HMDS to refuse under the situation that aquation handles, ethanol molecule (CH for example arranged because be in that space inwall etc. is residual
3OH), hydrone (H
2O) refuse aquation under etc. the state and handle, so the hydroxy (correctly saying, is the hydrogen in the hydroxy) in the ethanol molecule, hydrone etc. is by Si (CH
3)
3Base replaces.Therefore, Si (CH
3)
3Base is insufficient to the replacement of the hydroxy in the space, and the film micro areas such as inwall that just become the space are refused the inadequate state of aquation, the result, and electric charge drains to the outer air from electret under the frosting environment.
As mentioned above, according to this embodiment, because inside, space is being refused aquation processings that outgas before handling, thus remove after can handling gasifications such as the moisture that will remain in space inwall etc., ethanol molecule by the degassing, and then refuse the aquation processing.So, handle because can carry out the aquation of refusing of inside, space reliably, so space inwall etc. have very strong water repellency.The result is, drains in the outer gas of tube even also can prevent the electric charge that is accumulated in electret under the poor environment of the water droplet that freeze-outs easily, thereby can make the reliability raising of electret capacitor microphone.
Remarking additionally, in this embodiment, is the material with electro-deposition (electro-deposition) characteristic as long as become the insulating material of electret, not special the qualification.Can use for example silicon oxide film, silicon nitride film etc.
In this embodiment, in refusing the aquation processing, utilized HMDS, can also use for example N-trimethyl silane yl acetamide (TMSA:(N-Trimethylsilylacetamide), N, (BSA:(N, O-Bis (trimethylsilyl)-acetamide) waits other silylating reagent etc. to the two trimethyl silane yl acetamides of O-.
In this embodiment, carried out vacuum treatment and these two processing of baking processing as degassing processing, but can also only carry out vacuum treatment or only carry out baking processing replacing.
In this embodiment, the processing that both can outgas in same cavity is handled with refusing aquation, can outgas in different cavitys again and handle and refuse the aquation processing.
(second embodiment)
Below, with reference to the accompanying drawings second embodiment of the invention related electret capacitor microphone and manufacture method thereof are described.
Fig. 5 is the cutaway view of the electret capacitor microphone of this embodiment, particularly, is the cutaway view of integrally formed type electret capacitor microphone.
As shown in Figure 5, on Semiconductor substrate 101, be formed with silicon oxide film 102, simultaneously, the zone (fringe region) of defined reserved remove Semiconductor substrate 101 and silicon oxide film 102 forms film zone 113.Here, film zone 113 is to vibrate the zone that obtains after the part removal of Semiconductor substrate 101 in order to guarantee vibrating membrane 112 described later to receive pressure from the outside.Silicon nitride film 103 is formed on the silicon oxide film 102 film zone 113 is covered.Be formed with a conducting film on silicon nitride film 103, this conducting film can become bottom electrode 104 and lead-out wiring 115.On silicon nitride film 103, bottom electrode 104 and lead-out wiring 115, be formed with silicon oxide film 105 and silicon nitride film 106 in regular turn respectively.Here, in bottom electrode 104 and silicon oxide film 105, be formed with leakage sound hole 107.And silicon nitride film 103 and silicon nitride film 106 will be formed with that a part of bottom electrode 104 and the silicon oxide film 105 that leak sound hole 107 and be positioned at film zone 11 3 and be surrounded.
Remark additionally, constitute vibrating membrane 112 by the silicon nitride film 103 that is positioned at film zone 113, bottom electrode 104, silicon oxide film 105 and silicon nitride film 106.Silicon oxide film 105 is foil electrets that electric charge is accumulated.Above silicon nitride film 106, be formed with the fixedly film (top electrode) 110 that constitutes by the conducting film that is surrounded by silicon nitride film 114.At vibrating membrane 112 with fixedly be formed with space 109 between the film 110.The silicon nitride film 106 in 113 outsides, film zone with fixedly between the film 210 and at the silicon oxide film 102 in regional 113 outsides of film and fixedly be formed with silicon oxide film 108 between the film 110.Space 109 forms 113 coverings to major general's thin film region territory.The fixedly film 110 (perhaps covering the fixedly silicon nitride film 114 of film 110) that is arranged in 109 tops, space is formed with a plurality of acoustic holes 111.At silicon nitride film 114, fixedly form opening 116 in film 110 and the silicon oxide film 108 and allow the part of lead-out wiring 115 expose, in silicon nitride film 114, form opening 11 7 simultaneously and allow fixedly the part of film 110 expose.
This embodiment is characterised in that, be formed with silicon oxynitride film 151 at the surface element of silicon nitride film 103, silicon nitride film 106 and silicon nitride film 114 each film (particularly space 109 and towards the position of tube outer air), silicon oxynitride film 151 for example is with Si (CH
3)
3Silylation such as base are terminal surface (below be called silylation end surface 153).In other words, be provided with electret and the bottom electrode 104 that can vibrate, be that 109 position is covered by terminal silicon oxynitride film 151 with the silylation towards the space in the top electrode surface separately of fixedly film 110.
Remark additionally, the surface of the fixedly film 110 that exposes on the surface of the exposing surface of Semiconductor substrate 101, the lead-out wiring 115 that exposes from opening 116 places and from opening 117 is formed with silicon oxide film 152, and silicon oxide film 152 also has silylation end surface 153.Remark additionally,, also do not have so check, carry out some problems such as bonding wire at opening 116 and 117 usefulness probes because the thickness of silicon oxide film 152 is below about 1nm.
Below, the manufacture method to the related electret capacitor microphone of this embodiment describes with reference to the accompanying drawings.Particularly, Fig. 6 (a) is the manufacture method that shows the electret capacitor microphone of this embodiment to Fig. 6 (g), the cutaway view of each operation in the manufacture method of the electret capacitor microphone that particularly, to be basic structure identical with the integrally formed type electret capacitor microphone of this embodiment shown in Figure 5.Remark additionally, in Fig. 6 (g), represent the inscape identical, the part that repeats is just no longer done having illustrated with electret capacitor microphone shown in Figure 5 with same symbol at Fig. 6 (a).Simultaneously, for convenience of description, a part of inscape has been omitted diagram.
At first, shown in Fig. 6 (a), form for example silicon oxide film 102 of dielectric film at the surface and the back side of the Semiconductor substrate 101 that forms by for example silicon.Then, shown in Fig. 6 (b), on the silicon oxide film 102 of the surface of Semiconductor substrate 101 side, form silicon nitride film 103 in regular turn, become conducting film, silicon oxide film 105 and the silicon nitride film 106 of bottom electrode 104, simultaneously, being used in combination photoetching and etching technique forms bottom electrode 104, leaks sound hole 107 and vibrating membrane 11 2.
Afterwards, shown in Fig. 6 (c), the final sacrifice layer oxide-film 118 that is provided with space 109 that forms.
Then, shown in Fig. 6 (d), be used in combination film forming, photoetching and etching technique and on sacrifice layer oxide-film 118, form the fixedly film 110 that constitutes and have concaveconvex structure by the conducting film that is surrounded by silicon nitride film 114 (not shown)s.Afterwards, fixedly leaving acoustic hole 111 in the film 110.Afterwards, shown in Fig. 6 (e), be used in combination photoetching and etching technique and form from the back side one side of Semiconductor substrate 101 and pass the through hole 119 that this substrate arrives the silicon oxide film 102 of this substrate surface one side.
Then, shown in Fig. 6 (f), pass acoustic hole 111 a part of sacrifice layer oxide-film 118 wet etchings are formed space 109 between fixedly film 110 that is made of conducting film and vibrating membrane 112.At this moment, passing Lou, the silicon oxide film 102 of 107 pairs of Semiconductor substrate 101 surperficial sides of sound hole also carries out partially-etched.And, bottom electrode 104, be that 109 position is covered by silicon nitride film 106 and 114 towards the space in the top electrode surface separately of fixedly film 110.
So, just made integrally formed type electret capacitor microphone, its structure is such, plays the vibrating membrane 112 of the effect of bottom electrode and electret, that the fixedly film 110 that plays the effect of top electrode clips space 109 is opposed.
At last, shown in Fig. 6 (g), the electret capacitor microphone of this embodiment of containing space 109 is carried out the aquation of refusing described later handle (position of representing to be refused aquation with symbol 162 (stain)).So, just made the electret capacitor microphone of this embodiment.
In this embodiment, refusing aquation handles by degassing processing, oxidation (for example plasma oxidation) processing and silylation replacement (Si (CH
3)
3The base replacement) handling this three steps constitutes.Particularly, the inside in space 109 is finished after the degassing handles, handle surface element at silicon nitride film 103, silicon nitride film 106 and silicon nitride film 114 each film (particularly space 1 09 and towards the position of tube outer air) to form silicon oxynitride film 151 by carrying out plasma oxidation again.Afterwards, the electret capacitor microphone of this embodiment is put in the HMDS gaseous environment, to the surface of silicon oxynitride film 1 51 enrich the hydroxy that contains and carry out Si (CH
3)
3Base replaces to be handled.So just, formed silicon oxynitride film 151 with silylation end surface 153.This case inventor utilizes FT-IR method (fourier transform infrared analysis method) that the silicon oxynitride film 151 of such formation is analyzed and researched, and the result shows and do not have the hydroxy peak value that can confirm out.In other words, can infer the surface that to be present in silicon oxynitride film 151 hydroxy more than 99% by Si (CH
3)
3Base replaces.
Fig. 7 (a) is in order to the figure that refuses three steps that aquation handles of this embodiment to be described to Fig. 7 (d).Remark additionally, this embodiment refuses plasma oxidation, the Si (CH of aquation in handling
3)
3Base replaces, do not occur over just the surface of silicon nitride film 106, silicon nitride film 114 etc., also can occur in the whole surface of electret capacitor microphone, but arrive among Fig. 7 (d) at Fig. 7 (a), only show and refuse the relevant position of aquation processing for what prevent that fixedly film and vibrating membrane be adjacent to together to be carried out, in other words, only show silicon nitride film 106 and silicon nitride film 114 that space 109 reaches towards this space 109, the diagram of other inscape and explanation are all omitted and have not been carried.Fig. 7 (a) shows and refuses aquation processing beginning state before, and Fig. 7 (b) shows the state after the degassing is handled, and Fig. 7 (c) shows the state behind the plasma oxidation, and Fig. 7 (d) shows Si (CH
3)
3State after base replaces.
Shown in Fig. 7 (a), refusing before aquation handles beginning, 1 09 inside has ethanol molecule (CH for example in the space
3OH), hydrone (H
2O) etc.The ethanol molecule that is present in the inside in space 109 is except CH
3Beyond the OH, can imagine also to have acetone (acetone), different propylene organic solvents such as (isopropylene).In that there are hydroxy hardly in 109 the silicon nitride film 106 and the surface of silicon nitride film 114 towards the space, the NH base is very abundant.
At first, handling as the degassing of refusing first step that aquation handles, is the combination that electret capacitor microphone is exposed the vacuum treatment more than 1 hour under the pressure below the 25Pa for example and electret capacitor microphone is exposed the baking processing more than 24 hours under the temperature more than 300 ℃ for example.Remark additionally, the condition that the degassing is handled is not occur the peak value of moisture, ethanol etc. in the temperature programmed desorption analysis result.Handle if carry out the degassing of this embodiment, then shown in Fig. 7 (b), remain in the ethanol molecule (CH for example of the inwall in space 109
3OH), hydrone (H
2O) etc. be removed after the gasification.
Next, handling as the plasma oxidation of refusing second step that aquation handles, is for example to carry out in 6 hours by electret capacitor microphone is placed in the RF voltage of 500W being supplied with the plasma that mist produced of for example oxygen and nitrogen.So, shown in Fig. 7 (c), opening (acoustic hole 111) by silicon nitride film 114 arrives the silicon nitride film 106 of the inwall that constitutes space 109 and the oxygen plasma of silicon nitride film 114, surface oxidation with this silicon nitride film 106 and silicon nitride film 114 each film, consequently, form silicon oxynitride film 151 on the surface of silicon nitride film 106 and silicon nitride film 114.Here, have abundant hydroxy on the surface of 109 silicon oxynitride film 151 towards the space.
At last, as the Si (CH that refuses the 3rd step that aquation handles
3)
3Base replace to be handled, and is electret capacitor microphone is put into the (Si (CH in other words as HMDS
3)
3-NH-Si (CH
3)
3) carry out in the gaseous environment.So, shown in Fig. 7 (d), the hydroxy on silicon oxynitride film 151 surfaces is by Si (CH
3)
3Base replaces.The result is that the inwall in the space has formed by the Si (CH with very strong water repellency
3)
3The silicon oxynitride film 151 that base (in other words, the silylation end surface 153) covers.
Remark additionally, in this embodiment, with HMDS as in order to carry out Si (CH
3)
3The silanization materials that base replaces etc. moreover, for example can also utilize other silylating reagent such as TMSA, BSA etc.
Relevant this embodiment refuses effect that aquation handles and can test and confirm by for example carrying out contact angle.Particularly, the disclosed existing aquation of refusing is handled and to be applied in the patent documentation 1 under the situation in the disclosed electret capacitor microphone in patent documentation 2, towards the contact angle of the diaphragm face in space about 70 degree, but carrying out the refusing under the situation that aquation handles of this embodiment, can make towards the contact angle of the diaphragm face in space becomes value more than 80 degree.
As mentioned above, according to this embodiment, because the inside in space 109 is being refused aquation is handled that is silylation processings that outgas between replacing,, refuse the aquation processing afterwards again so can after gasifications such as the moisture that utilizes the degassing to handle to remain in the space 109, ethanol, remove.And, because carrying out before silylation replaces, to cover the silicon nitride film 106 of bottom electrode 104 and top electrode (fixedly film 110) and 114 surface oxidation respectively and form silicon oxynitride film 151, so can make the hydroxy that can become silylation replacement object very abundant.So, replace because can be reliably the inwall in space 109 be carried out silylation, thus can be in bottom electrode 104 and top electrode (fixedly film 110) surface separately 109 formation such as position are had the Si (CH of very strong water repellency towards the space
3)
3The silicon oxynitride film 151 that base (in other words, the silylation end surface 153) covers.Therefore, even under the poor environment of the water droplet that freeze-outs easily, also can prevent to be provided with the bottom electrode 104 of electret that is vibrating membrane 112 and fixing film 110 owing to condensing water droplet is close together, thereby can prevent to be accumulated in the electric charge of electret owing to condensing water droplet drains in the outer gas of tube, the result is that the reliability of electret capacitor microphone is improved.
According to this embodiment, what utilize when the surface oxidation of the silicon nitride film 106 that will cover bottom electrode 104 and top electrode (fixedly film 110) respectively and 114 forms silicon oxynitride film 151 is plasma oxidation.Therefore, even in little 109 inside, space of area of the opening that communicates with the tube outer air (acoustic hole 111 and leak sound hole 107), also can be reliably the surface oxidation of silicon nitride film 106 and 114 be formed silicon oxynitride film 151.
Remarking additionally, in this embodiment, is the material with electro-deposition characteristic as long as become the insulating material of electret, not special the qualification.Can use for example silicon oxide film, silicon nitride film etc.
In this embodiment, carried out vacuum treatment and these two processing of baking processing as degassing processing, but can also only carry out vacuum treatment or only carry out baking processing replacing it.
What utilize when the surface oxidation of the silicon nitride film 106 that will cover bottom electrode 104 and top electrode (fixedly film 110) respectively and 114 forms silicon oxynitride film 151 in this embodiment, is plasma oxidation.But can replace this way, for example utilize in the oxygen-containing gas environment for a long time baking processing (thermal oxidation) etc.
Practicality on the-industry-
In sum, the present invention relates to electret capacitor microphone and manufacture method thereof, can be to the space In firmly refuse hydration process, even accomplished under the poor environment of the water droplet that freeze-outs easily attached The electric charge of electret can not drain in the outer gas of tube yet, so the present invention is to realizing electret capacitor The high reliability of microphone is of great use.
Claims (9)
1. the manufacture method of an electret capacitor microphone, this electret capacitor microphone comprises: be provided with first electrode of electret, between it and described first electrode, accompany the space and with second electrode of described first electrode contraposition, it is characterized in that:
The manufacture method of this electret capacitor microphone comprises:
Operation a, to the processing that outgases of the inside in described space, and
Operation b refuses aquation to the inside in described space at least and handles after described operation a.
2. the manufacture method of electret capacitor microphone according to claim 1 is characterized in that:
In described operation b, under the hexamethyldisilazane gaseous environment, carry out heat treated.
3. according to the manufacture method of claim 1 or 2 described electret capacitor microphones, it is characterized in that:
In described operation a, or only carry out vacuum treatment, or only carry out baking processing, or carry out vacuum treatment and these two kinds of processing of baking processing.
4. integrally formed type electret capacitor microphone, it comprises: be provided with electret and first electrode that can vibrate, between it and described first electrode, accompany the space and with second electrode of described first electrode contraposition, it is characterized in that:
At least covered by silicon oxynitride film towards the position in described space in described first electrode and described second electrode surface separately with the silylation termination.
5. integrally formed type electret capacitor microphone according to claim 4 is characterized in that:
Described silylation is Si (CH
3)
3Base.
6. the manufacture method of an integrally formed type electret capacitor microphone, this electret capacitor microphone comprises: be provided with electret and first electrode that can vibrate, between it and described first electrode, accompany the space and with second electrode of described first electrode contraposition, and, at least covered by silicon nitride film towards the position in described space in described first electrode and described second electrode surface separately, it is characterized in that:
The manufacture method of this integrally formed type electret capacitor microphone comprises:
Operation a is to the processing that outgases of the inside in described space;
Operation b, the surface oxidation to the described silicon nitride film of major general after described operation a forms silicon oxynitride film; And
Operation c carries out silylation to the surface of described silicon oxynitride film at least and replaces processing after described operation b.
7. the manufacture method of integrally formed type electret capacitor microphone according to claim 6 is characterized in that:
Carrying out plasma oxidation in described operation b handles.
8. according to the manufacture method of claim 6 or 7 described integrally formed type electret capacitor microphones, it is characterized in that:
In described operation c, under the hexamethyldisilazane gaseous environment, carry out heat treated.
9. according to the manufacture method of claim 6 or 7 described integrally formed type electret capacitor microphones, it is characterized in that:
In described operation a, or only carry out vacuum treatment, or only carry out baking processing, or carry out vacuum treatment and these two kinds of processing of baking processing.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006356039 | 2006-12-28 | ||
| JP2006356039 | 2006-12-28 | ||
| JP2007223874 | 2007-08-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101212836A true CN101212836A (en) | 2008-07-02 |
Family
ID=39612402
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2007101860950A Pending CN101212836A (en) | 2006-12-28 | 2007-11-15 | Electret condenser microphone and manufacturing method thereof |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2008182666A (en) |
| CN (1) | CN101212836A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106982002A (en) * | 2017-05-26 | 2017-07-25 | 成都润泰茂成科技有限公司 | It is a kind of to stablize the micro-vibration TRT for preserving electric charge |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101096548B1 (en) | 2009-11-06 | 2011-12-20 | 주식회사 비에스이 | Mems microphone and manufacturing method of the same |
| JP6554742B2 (en) | 2014-10-22 | 2019-08-07 | 国立大学法人静岡大学 | Electret element, microphone equipped with the electret element, and method for manufacturing the electret element |
| WO2022254903A1 (en) | 2021-05-31 | 2022-12-08 | 株式会社鷺宮製作所 | Electret device |
-
2007
- 2007-08-30 JP JP2007223874A patent/JP2008182666A/en not_active Withdrawn
- 2007-11-15 CN CNA2007101860950A patent/CN101212836A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106982002A (en) * | 2017-05-26 | 2017-07-25 | 成都润泰茂成科技有限公司 | It is a kind of to stablize the micro-vibration TRT for preserving electric charge |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2008182666A (en) | 2008-08-07 |
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