JP2018118356A - Mems element and method for manufacturing same - Google Patents

Mems element and method for manufacturing same Download PDF

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JP2018118356A
JP2018118356A JP2017012679A JP2017012679A JP2018118356A JP 2018118356 A JP2018118356 A JP 2018118356A JP 2017012679 A JP2017012679 A JP 2017012679A JP 2017012679 A JP2017012679 A JP 2017012679A JP 2018118356 A JP2018118356 A JP 2018118356A
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silicon substrate
spacer
oxide film
movable electrode
thermal oxide
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JP6863545B2 (en
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孝英 臼井
Takahide Usui
孝英 臼井
新一 荒木
Shinichi Araki
新一 荒木
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New Japan Radio Co Ltd
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Abstract

PROBLEM TO BE SOLVED: To provide a MEMS element of which breakage is prevented, and a method for manufacturing said MEMS element.SOLUTION: The MEMS element is provided in which an air gap is formed by arranging a silicon substrate 1 comprising a back chamber 11, and a stationery electrode 8 and a movable electrode 6 on the silicon substrate with a first spacer 12 interposed therebetween. The MEMS element comprises: a second spacer 13 between the silicon substrate and the movable electrode; and a step part between a side surface end 14 of the back chamber and the second spacer. The step part becomes a smooth shape by removing a thermal oxide film 2 formed on a part of the silicon substrate, no projection is formed on the second spacer, so that breakage of the movable electrode is prevented.SELECTED DRAWING: Figure 2

Description

本発明は、ＭＥＭＳ素子に関し、特にマイクロフォン、各種センサ、スイッチ等として用いられる容量型のＭＥＭＳ素子およびその製造方法に関する。   The present invention relates to a MEMS element, and more particularly to a capacitive MEMS element used as a microphone, various sensors, switches, and the like, and a method for manufacturing the same.

従来、半導体プロセスを用いたＭＥＭＳ(Micro Electro Mechanical Systems)素子は、半導体基板上に固定電極、犠牲層（絶縁膜）および可動電極を形成した後、犠牲層の一部を除去することで、スペーサーを介して固定された固定電極と可動電極との間にエアーギャップ（中空）構造が形成されている。   Conventionally, a MEMS (Micro Electro Mechanical Systems) element using a semiconductor process has a fixed electrode, a sacrificial layer (insulating film), and a movable electrode formed on a semiconductor substrate, and then a part of the sacrificial layer is removed to form a spacer. An air gap (hollow) structure is formed between the fixed electrode fixed via the movable electrode and the movable electrode.

例えば、容量型のＭＥＭＳ素子であるコンデンサマイクロフォンでは、音圧を通過させる複数の貫通孔を備えた固定電極と、音圧を受けて振動する可動電極（ダイアフラム膜）とを対向して配置し、音圧を受けて振動する可動電極の変位を電極間の容量変化として検出する構成となっている。   For example, in a capacitor microphone that is a capacitive MEMS element, a fixed electrode having a plurality of through holes that allow sound pressure to pass therethrough and a movable electrode (diaphragm film) that vibrates in response to the sound pressure are arranged to face each other. The displacement of the movable electrode that vibrates in response to sound pressure is detected as a change in capacitance between the electrodes.

図４は、一般的なコンデンサマイクロフォンの製造方法の説明図である。まず、結晶方位（１００）面の厚さ４２０μｍのシリコン基板１上に、厚さ１μｍ程度の熱酸化膜２を形成し、熱酸化膜２上に、ＣＶＤ（Chemical Vapor Deposition）法により厚さ０．２〜２．０μｍ程度の導電性ポリシリコン膜を積層形成する。次に導電性ポリシリコン膜を通常のフォトリソグラフ法によりパターニングし、可動電極６を形成する（図４ａ）。   FIG. 4 is an explanatory diagram of a general method for manufacturing a condenser microphone. First, a thermal oxide film 2 having a thickness of about 1 μm is formed on a silicon substrate 1 having a crystal orientation (100) plane of 420 μm, and a thickness of 0 is formed on the thermal oxide film 2 by a CVD (Chemical Vapor Deposition) method. A conductive polysilicon film having a thickness of about 2 to 2.0 μm is laminated. Next, the conductive polysilicon film is patterned by a normal photolithography method to form the movable electrode 6 (FIG. 4a).

次に、可動電極６上に厚さ２．０〜５．０μｍ程度の第１のスペーサーとなるＵＳＧ(Undoped Silicate Glass)膜からなる犠牲層７を積層形成し、さらに、犠牲層７上に厚さ０．１〜１．０μｍ程度の導電性ポリシリコン膜を積層形成する。導電性ポリシリコン膜を通常のフォトリソグラフ法によりパターニングし、固定電極８を形成する。固定電極８上には、さらに減圧ＣＶＤ法により窒化膜を積層形成し、固定電極８と一体となったバックプレート９を形成する。固定電極８とバックプレート９には貫通孔１０を形成し、犠牲層７を露出させる（図４ｂ）。   Next, a sacrificial layer 7 made of a USG (Undoped Silicate Glass) film serving as a first spacer having a thickness of about 2.0 to 5.0 μm is laminated on the movable electrode 6, and the sacrificial layer 7 is further thickened. A conductive polysilicon film having a thickness of about 0.1 to 1.0 μm is stacked. The conductive polysilicon film is patterned by a normal photolithography method to form the fixed electrode 8. A nitride film is further laminated on the fixed electrode 8 by a low pressure CVD method to form a back plate 9 integrated with the fixed electrode 8. A through hole 10 is formed in the fixed electrode 8 and the back plate 9 to expose the sacrificial layer 7 (FIG. 4b).

その後、シリコン基板１を裏面側から熱酸化膜２が露出するまでシリコン基板１をエッチングすることでバックチャンバー１１を形成する。最後に貫通孔１０から犠牲層７の一部をエッチングし、第１のスペーサー１２を形成すると同時に、バックチャンバー１１側に残る熱酸化膜の一部をエッチングし、第２のスペーサー１３を形成し、固定電極８と可動電極６が対向するＭＥＭＳ素子を形成する（図４ｃ）。このような一般的なコンデンサマイクロフォンの製造方法は、例えば特許文献１に記載されている。   Then, the back chamber 11 is formed by etching the silicon substrate 1 until the thermal oxide film 2 is exposed from the back surface side. Finally, a part of the sacrificial layer 7 is etched from the through hole 10 to form the first spacer 12, and at the same time, a part of the thermal oxide film remaining on the back chamber 11 side is etched to form the second spacer 13. Then, a MEMS element in which the fixed electrode 8 and the movable electrode 6 are opposed to each other is formed (FIG. 4c). Such a general method of manufacturing a condenser microphone is described in Patent Document 1, for example.

特開２００７−２７４０９６号公報JP 2007-274096 A

ところで、このようにシリコン基板１をエッチングすることでバックチャンバー１１を形成すると、非常に深くシリコン基板１をエッチングする必要があるため、シリコン基板１の底面（バックチャンバー側面端部１５）は、スムーズな円形とはならず突起部が残ってしまう。図５は、バックチャンバー１１の側面端部と熱酸化膜の一部をエッチングして形成した第２のスペーサー１３の端部を可動電極６側から模式的に表している。図５に示すように、バックチャンバー側面端部１５に突起部１６が形成されると、熱酸化膜は等方的にエッチングされるため、第２のスペーサー１３の側端部にも突起部１７が形成されてしまう。このように突起部１７が存在する第２のスペーサー１３に支持された可動電極６に圧力が加わると、第２のスペーサー１３の突起部１７先端と可動電極６との接続点１８に応力が集中し、可動電極６に破壊しやすくなってしまうという問題点があった。   By the way, when the back chamber 11 is formed by etching the silicon substrate 1 in this way, it is necessary to etch the silicon substrate 1 very deeply, so that the bottom surface of the silicon substrate 1 (back chamber side surface end 15) is smooth. It does not become a circular shape, and the protrusion remains. FIG. 5 schematically shows an end portion of the second spacer 13 formed by etching a side end portion of the back chamber 11 and a part of the thermal oxide film from the movable electrode 6 side. As shown in FIG. 5, when the protrusion 16 is formed on the back chamber side end 15, the thermal oxide film is isotropically etched, so that the protrusion 17 is also formed on the side end of the second spacer 13. Will be formed. When pressure is applied to the movable electrode 6 supported by the second spacer 13 where the protrusion 17 is present in this way, stress is concentrated at the connection point 18 between the tip of the protrusion 17 of the second spacer 13 and the movable electrode 6. However, there is a problem that the movable electrode 6 is easily broken.

本発明は、上記問題点を解消し、ＭＥＭＳ素子の破壊を防止することができるＭＥＭＳ素子およびその製造方法を提供することを目的とする。   An object of this invention is to provide the MEMS element which can eliminate the said problem, and can prevent destruction of a MEMS element, and its manufacturing method.

上記目的を達成するため、本願請求項１に係る発明は、バックチャンバーを備えたシリコン基板と、該シリコン基板上に、第１のスペーサーを挟んで固定電極と可動電極とを配置することでエアーギャップが形成されたＭＥＭＳ素子において、
前記シリコン基板と前記可動電極の間に第２のスペーサーを備え、
該第２のスペーサーを構成する熱酸化膜と前記バックチャンバーを構成する前記シリコン基板の側面との間に該シリコン基板の一部が切り欠かれた段部を備え、該段部は、前記シリコン基板の一部に形成された前記熱酸化膜の除去により露出した前記シリコン基板からなることを特徴とする。 In order to achieve the above object, the invention according to claim 1 of the present application provides a silicon substrate provided with a back chamber, and a fixed electrode and a movable electrode arranged on the silicon substrate with a first spacer interposed therebetween. In a MEMS element in which a gap is formed,
A second spacer is provided between the silicon substrate and the movable electrode;
A step portion in which a part of the silicon substrate is cut out is provided between a thermal oxide film constituting the second spacer and a side surface of the silicon substrate constituting the back chamber. The silicon substrate is exposed by removing the thermal oxide film formed on a part of the substrate.

本願請求項２に係る発明は、バックチャンバーを備えたシリコン基板上に、第１のスペーサーを挟んで固定電極と可動電極とを配置したＭＥＭＳ素子の製造方法において、第２のスペーサー形成予定領域の内側に環状形状に配置する凹部内を充填するように前記シリコン基板表面を熱酸化する工程と、前記シリコン基板表面の熱酸化膜上に、前記可動電極を形成する工程と、前記可動電極上に、絶縁膜を形成する工程と、前記絶縁膜上に、前記固定電極を形成する工程と、前記固定電極に貫通孔を形成する工程と、前記シリコン基板の一部をエッチング除去し、側面が前記凹部に位置するように前記バックチャンバーを形成する工程と、前記貫通孔から前記絶縁膜の一部をエッチング除去し、前記第１のスペーサーを形成し、前記固定電極と前記可動電極との間にエアーギャップを形成すると同時に、前記凹部内に埋め込まれた熱酸化膜を除去し、前記シリコン基板表面の熱酸化膜の一部を残し、第２のスペーサーを形成する工程と、を含むことを特徴とする。   The invention according to claim 2 of the present application is directed to a MEMS device manufacturing method in which a fixed electrode and a movable electrode are disposed on a silicon substrate having a back chamber with a first spacer interposed therebetween. A step of thermally oxidizing the surface of the silicon substrate so as to fill a concave portion disposed in an annular shape inside; a step of forming the movable electrode on a thermal oxide film on the surface of the silicon substrate; and A step of forming an insulating film; a step of forming the fixed electrode on the insulating film; a step of forming a through hole in the fixed electrode; Forming the back chamber so as to be located in the recess; etching away a part of the insulating film from the through hole; forming the first spacer; and Forming a second spacer by forming an air gap between the movable electrode and removing the thermal oxide film embedded in the recess to leave a part of the thermal oxide film on the surface of the silicon substrate; It is characterized by including these.

本発明のＭＥＭＳ素子の製造方法により製造したＭＥＭＳ素子は、バックチャンバーの側面端部に突起部が形成されたとしても、第２のスペーサーの側端部には突起部が形成されずスムーズな円形形状とすることで、可動電極が破壊に至ることを防止できる。また突起部は、可動電極から離れ、可動電極の振動の際に突起部に接触して破損することも防止できる。   The MEMS element manufactured by the method for manufacturing a MEMS element according to the present invention has a smooth circular shape with no protrusions formed on the side edges of the second spacer even if the protrusions are formed on the side edges of the back chamber. By adopting the shape, the movable electrode can be prevented from being destroyed. Further, the protruding portion can be prevented from being separated from the movable electrode and being damaged due to contact with the protruding portion when the movable electrode vibrates.

本発明のＭＥＭＳ素子の製造方法は、通常の半導体装置の製造工程で、一般的に用いられている工程のみで構成されているため、非常に安定的に、また安価にＭＥＭＳ素子を形成することができるという利点がある。特にシリコン基板の熱酸化により、側面及び底面がスムーズな形状となっている凹部内に充填された熱酸化膜からエッチングを開始することで第２のスペーサーを形成するため、バックチャンバーの側面端部に突起部が残されていても、第２のスペーサーの側端部に突起を形成することがなくなるという利点がある。   Since the MEMS element manufacturing method of the present invention is composed of only a generally used process in a normal semiconductor device manufacturing process, the MEMS element can be formed very stably and inexpensively. There is an advantage that can be. In particular, since the second spacer is formed by starting etching from the thermal oxide film filled in the recess having a smooth shape on the side surface and bottom surface due to the thermal oxidation of the silicon substrate, the side end portion of the back chamber There is an advantage that no projection is formed on the side end of the second spacer even if the projection is left behind.

本発明のＭＥＭＳ素子の製造工程の説明図である。It is explanatory drawing of the manufacturing process of the MEMS element of this invention. 本発明のＭＥＭＳ素子の製造工程の説明図である。It is explanatory drawing of the manufacturing process of the MEMS element of this invention. 本発明のＭＥＭＳ素子の製造方法の効果を説明する図である。It is a figure explaining the effect of the manufacturing method of the MEMS element of this invention. 従来のＭＥＭＳ素子の製造工程の説明図である。It is explanatory drawing of the manufacturing process of the conventional MEMS element. 従来のＭＥＭＳ素子の製造方法の効果を説明する図である。It is a figure explaining the effect of the manufacturing method of the conventional MEMS element.

本発明に係るＭＥＭＳ素子は、バックチャンバーの側面端部と第２のスペーサーが形成される領域との間が一部厚くなるようにシリコン基板表面を熱酸化して熱酸化膜を形成する。この熱酸化膜は通常の半導体装置の製造工程に従い形成されるため、厚さの厚い部分の形状は、スムーズな環状、例えば円形形状に形成することができる。しかも、第２のスペーサーとして残る熱酸化膜の内側に厚い熱酸化膜を形成することで、バックチャンバーの側面端部に残る突起部の影響を受けない構造とすることが可能となる。以下、本発明のＭＥＭＳ素子の製造方法に従い、本発明の実施例について説明する。   In the MEMS device according to the present invention, the surface of the silicon substrate is thermally oxidized to form a thermal oxide film so that a portion between the side end portion of the back chamber and the region where the second spacer is formed is thickened. Since this thermal oxide film is formed in accordance with a normal manufacturing process of a semiconductor device, the thick portion can be formed into a smooth annular shape, for example, a circular shape. In addition, by forming a thick thermal oxide film inside the thermal oxide film remaining as the second spacer, it is possible to achieve a structure that is not affected by the protrusions remaining at the side edges of the back chamber. Hereinafter, according to the method for manufacturing a MEMS device of the present invention, examples of the present invention will be described.

本発明の実施例について、製造工程に従い説明する。まず、結晶方位（１００）面の厚さ４２０μｍのシリコン基板１上に、厚さ１μｍ程度の熱酸化膜２（ＳｉＯ2）を形成し、通常のフォトリソグラフ法により熱酸化膜２をパターニングし、シリコン基板１に幅０．５μｍ、深さ１μｍ程度の環状溝３をシリコン基板１の縁周に沿って複数形成する。このとき、環状溝３のうち最も外側の環状溝３ａの外周が、バックチャンバー形成予定位置よりも外側で、第２のスペーサー形成予定位置より内側になるように形成する(図１ａ)。 Examples of the present invention will be described according to the manufacturing process. First, a thermal oxide film 2 (SiO 2 ) having a thickness of about 1 μm is formed on a silicon substrate 1 having a crystal orientation (100) plane of 420 μm, and the thermal oxide film 2 is patterned by a normal photolithography method. A plurality of annular grooves 3 having a width of about 0.5 μm and a depth of about 1 μm are formed in the silicon substrate 1 along the periphery of the silicon substrate 1. At this time, it forms so that the outer periphery of the outermost annular groove 3a among the annular grooves 3 is outside the back chamber formation planned position and inside the second spacer formation planned position (FIG. 1a).

その後、シリコン基板１表面を熱酸化することにより、環状溝３間のシリコン基板４を熱酸化し、環状凹部５を形成すると同時に環状凹部５内を熱酸化膜２ａで埋める（図１ｂ）。なお、環状凹部５内を熱酸化膜２ａで埋めるために、環状溝３を複数形成すると熱酸化後に熱酸化膜２ａの表面が平坦となり、簡便な方法となる。   Thereafter, the surface of the silicon substrate 1 is thermally oxidized to thermally oxidize the silicon substrate 4 between the annular grooves 3, thereby forming the annular recess 5 and simultaneously filling the annular recess 5 with the thermal oxide film 2a (FIG. 1b). If a plurality of annular grooves 3 are formed to fill the annular recess 5 with the thermal oxide film 2a, the surface of the thermal oxide film 2a becomes flat after thermal oxidation, which is a simple method.

以下、通常の製造工程に従い、熱酸化膜２上に、ＣＶＤ（Chemical Vapor Deposition）法により厚さ０．２〜２．０μｍ程度の導電性ポリシリコン膜を積層形成する。次に導電性ポリシリコン膜を通常のフォトリソグラフ法によりパターニングし、可動電極６を形成する（図１ｃ）。   Thereafter, a conductive polysilicon film having a thickness of about 0.2 to 2.0 μm is laminated on the thermal oxide film 2 by a CVD (Chemical Vapor Deposition) method in accordance with a normal manufacturing process. Next, the conductive polysilicon film is patterned by a normal photolithographic method to form the movable electrode 6 (FIG. 1c).

次に、可動電極６上に厚さ２．０〜５．０μｍ程度の第１のスペーサーとなるＵＳＧ(Undoped Silicate Glass)膜からなる犠牲層７を積層形成し、さらに、犠牲層７上に厚さ０．１〜１．０μｍ程度の導電性ポリシリコン膜を積層形成する。導電性ポリシリコン膜を通常のフォトリソグラフ法によりパターニングし、固定電極８を形成する。固定電極８上には、さらに減圧ＣＶＤ法により窒化膜を積層形成し、固定電極８と一体となったバックプレート９を形成する。固定電極８とバックプレート９には貫通孔１０を形成し、犠牲層７を露出させる（図２ａ）。   Next, a sacrificial layer 7 made of a USG (Undoped Silicate Glass) film serving as a first spacer having a thickness of about 2.0 to 5.0 μm is laminated on the movable electrode 6, and the sacrificial layer 7 is further thickened. A conductive polysilicon film having a thickness of about 0.1 to 1.0 μm is stacked. The conductive polysilicon film is patterned by a normal photolithography method to form the fixed electrode 8. A nitride film is further laminated on the fixed electrode 8 by a low pressure CVD method to form a back plate 9 integrated with the fixed electrode 8. A through hole 10 is formed in the fixed electrode 8 and the back plate 9 to expose the sacrificial layer 7 (FIG. 2a).

その後、シリコン基板１を裏面側から熱酸化膜２が露出するまでエッチングすることでバックチャンバー１１を形成する。このとき、バックチャンバー１１の側壁端部が、図２（ｂ）に示すように、先に形成した環状凹部５内に埋め込まれた熱酸化膜２ａの底部となるように配置する。   Then, the back chamber 11 is formed by etching the silicon substrate 1 from the back surface side until the thermal oxide film 2 is exposed. At this time, it arrange | positions so that the side wall edge part of the back chamber 11 may become the bottom part of the thermal oxide film 2a embedded in the cyclic | annular recessed part 5 formed previously, as shown in FIG.2 (b).

最後に貫通孔１０から犠牲層７の一部をエッチングし、第１のスペーサー１２を形成すると同時に、バックチャンバー１１側に残る熱酸化膜２の一部をエッチングし、第２のスペーサー１３を形成し、固定電極８と可動電極６が対向するＭＥＭＳ素子を形成する（図２ｃ）。   Finally, a part of the sacrificial layer 7 is etched from the through hole 10 to form the first spacer 12, and at the same time, a part of the thermal oxide film 2 remaining on the back chamber 11 side is etched to form a second spacer 13. Then, a MEMS element in which the fixed electrode 8 and the movable electrode 6 are opposed to each other is formed (FIG. 2c).

このように形成するＭＥＭＳ素子は、図３に示すように、バックチャンバー１１を形成する際、バックチャンバーの側面端部１４に突起部１６が形成されたとしても、第２のスペーサー１３の側端部には突起が形成されずスムーズな円形形状となる。これは、熱酸化膜がエッチングされる際、熱酸化膜２ａの側面部２ｂと底面がスムーズな円形形状であることにより、このスムーズな円形形状の面をトレースするように等方的なエッチングが進行し、突起部が形成されないためである。また、バックチャンバーの側壁端部１４に突起部１６が形成されているために突起をトレースするように熱酸化膜２のエッチングが進行するものの、このエッチングは熱酸化膜２ａの側面部２ｃに達するとすべての熱酸化膜２ａがエッチングされ、第２のスペーサー１３のエッチング形状に影響を与えることがない。このように、突起のない構造とすることにより、可動電極６に圧力が加わっても、第２のスペーサー１３と可動電極６の特定の接続点に応力が集中することはなく、可動電極６の破壊を防止することができることになる。   As shown in FIG. 3, the MEMS element formed in this way has a side end of the second spacer 13, even when the protrusion 16 is formed on the side end 14 of the back chamber when the back chamber 11 is formed. No protrusions are formed on the part, and a smooth circular shape is obtained. This is because when the thermal oxide film is etched, the side surface 2b and the bottom surface of the thermal oxide film 2a have a smooth circular shape, so that isotropic etching is performed so as to trace the smooth circular surface. This is because the process proceeds and no protrusion is formed. Further, since the protrusion 16 is formed on the side wall end 14 of the back chamber, the etching of the thermal oxide film 2 proceeds so as to trace the protrusion, but this etching reaches the side surface 2c of the thermal oxide film 2a. Then, all the thermal oxide films 2a are etched, and the etching shape of the second spacer 13 is not affected. Thus, by adopting a structure having no protrusion, even if pressure is applied to the movable electrode 6, no stress is concentrated on a specific connection point between the second spacer 13 and the movable electrode 6. Destruction can be prevented.

以上本発明について説明したか、本発明はこれに限定されるものではなく、種々変更可能である。例えば、環状凹部５内に熱酸化膜を充填する方法は、図１（ａ）に示すように複数の環状溝３を形成する方法に限定されるものではなく、幅の広い凹部内に熱酸化膜を充填して環状凹部５を形成してもよい。また、可動電極や熱酸化膜が埋め込まれる凹部等の形状は円形に限るものでもない。   The present invention has been described above, or the present invention is not limited to this, and various modifications can be made. For example, the method of filling the annular recess 5 with the thermal oxide film is not limited to the method of forming the plurality of annular grooves 3 as shown in FIG. The annular recess 5 may be formed by filling a film. Further, the shape of the concave portion or the like in which the movable electrode or the thermal oxide film is embedded is not limited to a circle.

１：シリコン基板、２：熱酸化膜、２ａ，２ｂ，２ｃ：環状凹部に埋め込まれた熱酸化膜、３，３ａ：環状溝、４：環状溝３間のシリコン基板、５：環状凹部、６：可動電極、７：犠牲層、８：固定電極、９：バックプレート、１０：貫通孔、１１：バックチャンバー、１２：第１のスペーサー、１３：第２のスペーサー、１４，１５：バックチャンバー側面端部、１６，１７：突起部、１８：接続点 1: silicon substrate, 2: thermal oxide film, 2a, 2b, 2c: thermal oxide film embedded in an annular recess, 3, 3a: annular groove, 4: silicon substrate between annular grooves 3, 5: annular recess, 6 : Movable electrode, 7: sacrificial layer, 8: fixed electrode, 9: back plate, 10: through hole, 11: back chamber, 12: first spacer, 13: second spacer, 14, 15: side surface of back chamber End, 16, 17: Projection, 18: Connection point

Claims (2)

バックチャンバーを備えたシリコン基板と、該シリコン基板上に、第１のスペーサーを挟んで固定電極と可動電極とを配置することでエアーギャップが形成されたＭＥＭＳ素子において、
前記シリコン基板と前記可動電極の間に第２のスペーサーを備え、
該第２のスペーサーを構成する熱酸化膜と前記バックチャンバーを構成する前記シリコン基板の側面との間に該シリコン基板の一部が切り欠かれた段部を備え、該段部は、前記シリコン基板の一部に形成された前記熱酸化膜の除去により露出した前記シリコン基板からなることを特徴とするＭＥＭＳ素子。 In a MEMS device in which an air gap is formed by disposing a silicon substrate with a back chamber and a fixed electrode and a movable electrode on the silicon substrate with a first spacer interposed therebetween,
A second spacer is provided between the silicon substrate and the movable electrode;
A step portion in which a part of the silicon substrate is cut out is provided between a thermal oxide film constituting the second spacer and a side surface of the silicon substrate constituting the back chamber. A MEMS device comprising the silicon substrate exposed by removing the thermal oxide film formed on a part of the substrate. バックチャンバーを備えたシリコン基板上に、第１のスペーサーを挟んで固定電極と可動電極とを配置したＭＥＭＳ素子の製造方法において、
第２のスペーサー形成予定領域の内側に環状形状に配置する凹部内を充填するように前記シリコン基板表面を熱酸化する工程と、
前記シリコン基板表面の熱酸化膜上に、前記可動電極を形成する工程と、
前記可動電極上に、絶縁膜を形成する工程と、
前記絶縁膜上に、前記固定電極を形成する工程と、
前記固定電極に貫通孔を形成する工程と、
前記シリコン基板の一部をエッチング除去し、側面が前記凹部に位置するように前記バックチャンバーを形成する工程と、
前記貫通孔から前記絶縁膜の一部をエッチング除去し、前記第１のスペーサーを形成し、前記固定電極と前記可動電極との間にエアーギャップを形成すると同時に、前記凹部内に埋め込まれた熱酸化膜を除去し、前記シリコン基板表面の熱酸化膜の一部を残し、第２のスペーサーを形成する工程と、を含むことを特徴とするＭＥＭＳ素子の製造方法。 In a method of manufacturing a MEMS element in which a fixed electrode and a movable electrode are arranged on a silicon substrate having a back chamber with a first spacer interposed therebetween,
Thermally oxidizing the silicon substrate surface so as to fill the inside of the concave portion disposed in an annular shape inside the second spacer formation scheduled region;
Forming the movable electrode on the thermal oxide film on the surface of the silicon substrate;
Forming an insulating film on the movable electrode;
Forming the fixed electrode on the insulating film;
Forming a through hole in the fixed electrode;
Etching away a portion of the silicon substrate and forming the back chamber so that the side surface is located in the recess;
A part of the insulating film is removed by etching from the through hole, the first spacer is formed, an air gap is formed between the fixed electrode and the movable electrode, and at the same time, the heat embedded in the recess Removing the oxide film, leaving a part of the thermal oxide film on the surface of the silicon substrate, and forming a second spacer.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110868681A (en) * 2019-11-29 2020-03-06 中芯集成电路制造(绍兴)有限公司 MEMS microphone warpage compensation method and MEMS microphone wafer

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008244752A (en) * 2007-03-27 2008-10-09 Yamaha Corp Electrostatic pressure transducer
JP2016002625A (en) * 2014-06-18 2016-01-12 新日本無線株式会社 MEMS element
JP2016022544A (en) * 2014-07-17 2016-02-08 新日本無線株式会社 MEMS element

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008244752A (en) * 2007-03-27 2008-10-09 Yamaha Corp Electrostatic pressure transducer
JP2016002625A (en) * 2014-06-18 2016-01-12 新日本無線株式会社 MEMS element
JP2016022544A (en) * 2014-07-17 2016-02-08 新日本無線株式会社 MEMS element

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110868681A (en) * 2019-11-29 2020-03-06 中芯集成电路制造(绍兴)有限公司 MEMS microphone warpage compensation method and MEMS microphone wafer
CN110868681B (en) * 2019-11-29 2021-09-14 绍兴中芯集成电路制造股份有限公司 MEMS microphone warpage compensation method and MEMS microphone wafer

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