JP6507999B2 - MEMS sensor - Google Patents

Description

  A MEMS sensor is disclosed herein.

  Patent Document 1 discloses a MEMS sensor. The MEMS sensor comprises a movable electrode and two fixed electrodes arranged on the stairs on both sides of the movable electrode.

JP 2000-49358 A

  When manufacturing the MEMS sensor of Patent Document 1, the sacrificial layer is formed in advance in a stepped shape by etching the sacrificial layer, the movable electrode and the fixed electrode are stacked thereon, and the sacrificial layer is finally removed Do. In the MEMS sensor manufactured in this manner, it is difficult to form the sacrificial layer between the movable electrode and the fixed electrode in a step-like manner with high accuracy, and therefore, the step amount tends to vary. In particular, in a MEMS sensor having a stepped comb-tooth electrode pair, a technology capable of forming the amount of level difference between two comb-tooth electrodes with high accuracy is expected.

  The present specification provides a technique for solving the above-mentioned problems. In this specification, in a MEMS sensor having a stepped comb-tooth electrode pair, a technique is provided that can accurately form the level difference between two comb-tooth electrodes.

  The MEMS sensor disclosed in the present specification is disposed to mesh with the first fixed comb electrode and the first fixed comb electrode, and the position of the upper end is substantially equal to the position of the upper end of the first fixed comb electrode And the first movable comb electrode, the second fixed comb electrode, and the second fixed comb electrode are arranged to mesh with the first movable comb electrode, the position of the lower end being substantially equal to the position of the lower end of the first fixed comb electrode. The second movable comb electrode is provided such that the position of the upper end is substantially equal to the position of the upper end of the second fixed comb electrode, and the position of the lower end is substantially equal to the position of the lower end of the second fixed comb electrode. In the MEMS sensor, a first additional comb electrode made of a conductive material is provided above the first movable comb electrode, and a second addition made of a conductive material is provided below the second movable comb electrode. A comb electrode is provided.

  In the MEMS sensor described above, the first fixed comb electrode and the first additional comb electrode are used as a stepped comb electrode pair, and the second fixed comb electrode and the second additional comb electrode are formed as a staggered comb electrode. It can be used as an electrode pair. In this MEMS sensor, the position of the lower end of the first additional comb electrode substantially coincides with the position of the upper end of the first fixed comb electrode, and the height of the first additional comb electrode is made of a conductive material. It is defined by the stacking height. Since the lamination height of the conductive material can be accurately adjusted, the step amount between the first fixed comb electrode and the first additional comb electrode can be adjusted with high accuracy. Similarly, in this MEMS sensor, the position of the lower end of the second additional comb electrode substantially coincides with the position of the lower end of the second fixed comb electrode, and the height of the second additional comb electrode is conductive It is defined by the lamination height of the elastic material. Since the lamination height of the conductive material can be adjusted with high accuracy, the step amount between the second fixed comb electrode and the second additional comb electrode can be adjusted with high accuracy. According to the above-described MEMS sensor, the first fixed comb electrode and the first additional comb electrode are formed of the staggered comb electrode pair, the second fixed comb electrode, and the second additional comb electrode. The level differences can be formed with high precision for the stepped comb-tooth electrode pairs.

  Further, in the above-described MEMS sensor, a stepped pair of comb-tooth electrodes composed of the first fixed comb-tooth electrode and the first additional comb-tooth electrode, a second fixed comb-tooth electrode and the second additional comb-tooth electrode The stepped comb-tooth electrode pairs have steps in opposite directions. With such a configuration, a MEMS sensor having a differential structure can be realized.

FIG. 2 is a top view of the MEMS sensor 2 of the first embodiment. FIG. 2 is a cross-sectional view of the MEMS sensor 2 according to the first embodiment as viewed from the II-II cross section. FIG. 3 is a cross-sectional view of the MEMS sensor 2 of the first embodiment as viewed from the III-III cross section. FIG. 6 is a view for explaining the operation of the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a view for explaining the method for manufacturing the MEMS sensor 2 of the first embodiment. FIG. 7 is a top view of a MEMS sensor 102 according to a second embodiment. FIG. 10 is a cross-sectional view of the MEMS sensor 102 of the second embodiment as viewed from the XVI-XVI cross section. FIG. 14 is a top view of a MEMS sensor 202 of Example 3. FIG. 16 is a cross-sectional view of the MEMS sensor 202 according to the third embodiment as viewed from the XVIII-XVIII cross section. FIG. 18 is a cross-sectional view of the MEMS sensor 202 according to the third embodiment as viewed from the XIX-XIX cross section. FIG. 14 is a view for explaining the operation of the MEMS sensor 202 of the third embodiment. FIG. 16 is a top view of a MEMS sensor 302 of Example 4. FIG. 20 is a cross-sectional view of the MEMS sensor 302 according to the fourth embodiment as viewed from the XXII-XXII cross section; FIG. 16 is a cross-sectional view of the MEMS sensor 302 of the fourth embodiment as seen from the XXIII-XXIII cross section. FIG. 16 is a view for explaining the operation of the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a view for explaining the method for manufacturing the MEMS sensor 302 of the fourth embodiment. FIG. 16 is a top view of a MEMS sensor 402 of Example 5. FIG. 18 is a cross-sectional view of the MEMS sensor 402 of the fifth embodiment as viewed from the XXXIV-XXXIV cross section; FIG. 16 is a top view of a MEMS sensor 502 of Example 6. FIG. 31 is a cross-sectional view of the MEMS sensor 502 of the sixth embodiment as viewed from the XXXVI-XXXVI cross section; Sectional drawing seen from the XXXVII-XXXVII section of the MEMS sensor 502 of Example 6. FIG. FIG. 18 is a view for explaining the operation of the MEMS sensor 502 of the sixth embodiment.

  In the MEMS sensor disclosed in this specification, the first movable comb electrode and the first additional comb electrode are electrically connected, and the second movable comb electrode and the second additional comb electrode are electrically connected. It can be configured as you are.

  According to the above MEMS sensor, the first movable comb electrode and the first additional comb electrode can be used as a single comb electrode, and the second movable comb electrode and the second additional comb electrode can be single. Can be used as a comb-tooth electrode. For this reason, it becomes unnecessary to wire the first additional comb electrode and the second additional comb electrode separately from the wiring to the first movable comb electrode and the second movable comb electrode.

  Alternatively, in the MEMS sensor disclosed in the present specification, the first movable comb electrode and the first additional comb electrode are electrically insulated, and the second movable comb electrode and the second additional comb electrode are electrically Can be configured to be isolated.

  According to the MEMS sensor described above, the first movable comb electrode and the first additional comb electrode can be used as separate comb electrodes, and the second movable comb electrode and the second additional comb electrode can be separated into combs. It can be used as a tooth electrode. Further, according to the MEMS sensor described above, since the initial facing area of the first additional comb electrode and the first fixed comb electrode is substantially zero, the parasitic capacitance between both can be extremely reduced. Since the initial opposing area of the additional 2 comb electrode and the second fixed comb electrode is substantially zero, the parasitic capacitance between both can be extremely reduced.

  In the MEMS sensor disclosed in the present specification, the first movable comb electrode and the first additional comb electrode are connected via an insulating film, and the second movable comb electrode and the second additional comb electrode are connected. It can comprise so that between may be connected via an insulating film.

  According to the above MEMS sensor, electrical insulation between the first movable comb electrode and the first additional comb electrode, and between the second movable comb electrode and the second additional comb electrode with a simple configuration. Electrical isolation can be realized.

  Alternatively, in the MEMS sensor disclosed in the present specification, the first movable comb electrode and the first additional comb electrode are connected via a PN junction, and the second movable comb electrode and the second additional comb electrode are connected The electrodes can be configured to be connected via a PN junction.

  According to the above MEMS sensor, electrical insulation between the first movable comb electrode and the first additional comb electrode, and between the second movable comb electrode and the second additional comb electrode with a simple configuration. Electrical isolation can be realized.

  In the MEMS sensor disclosed in the present specification, a third additional comb electrode made of a conductive material is provided below the first fixed comb electrode, and a conductive material is provided above the second fixed comb electrode. Can be configured to be provided with a fourth additional comb electrode made of

  According to the above-described MEMS sensor, the first movable comb electrode and the third additional comb electrode include the first comb electrode and the first additional comb electrode, and the first movable comb electrode and the third additional comb electrode. A stepped comb-tooth electrode pair having a step difference in the opposite direction to each other, and formed of a second fixed comb-tooth electrode and a second additional comb-tooth electrode, and a second movable comb-tooth electrode And the step-like comb electrode pair composed of the fourth additional comb electrode has steps in opposite directions to each other. With such a configuration, sensor sensitivity can be improved.

Example 1
1 to 3 show the MEMS sensor 2 of the present embodiment. In the MEMS sensor 2, a support layer 4 made of conductive single crystal silicon, an insulating layer 6 made of silicon oxide, and a sensor layer 8 mainly made of conductive single crystal silicon are sequentially stacked. Also, it is formed on the laminated substrate 10. In the following description, the stacking direction of the layered substrate 10 (the direction perpendicular to the sheet of FIG. 1, the vertical direction of FIGS. 2 and 3) is taken as the Z direction, and the in-plane direction of the layered substrate 10 is taken as the X direction and the Y direction. In the following description, the positive direction in the Z direction (upper direction in FIGS. 2 and 3) is referred to as the upper direction, and the negative direction in the Z direction (lower direction in FIGS. 2 and 3) is referred to as the lower direction. In the MEMS sensor 2 of the present embodiment, the insulating layer 6 is stacked above the support layer 4, and the sensor layer 8 is stacked above the insulating layer 6. The MEMS sensor 2 is used in combination with the arithmetic circuit 11.

  In the sensor layer 8, by selectively removing single crystal silicon by etching, the mass portion 12, the comb-tooth electrode portions 14a, 14b, 14c, 14d and the plate-like beam portions 16a, 16b, 16c, 16d and The peripheral portion 18, the comb-tooth electrode portions 20a, 20b, 20c and 20d, and the electrode support portions 22a, 22b, 22c and 22d are formed. Among them, the mass 12, the comb-tooth electrodes 14a, 14b, 14c, 14d, the plate-like beams 16a, 16b, 16c, 16d, and the peripheral portion 18 are integrally formed without a joint. Is maintained at the same potential. Further, the comb-tooth electrode portions 20a, 20b, 20c, and 20d are integrally formed seamlessly with the corresponding electrode support portions 22a, 22b, 22c, and 22d, respectively, and are maintained at the same potential.

  The mass portion 12 is formed in a rectangular shape when the MEMS sensor 2 is viewed in plan from above. Although not shown, the mass portion 12 is formed with a plurality of etching holes penetrating the mass portion 12 from the upper surface to the lower surface. The comb-tooth electrode portions 14a and 14b are provided at one end (the end on the right side of FIG. 1) of the mass 12 in the X direction, and the other end of the mass 12 in the X direction (FIG. 1) The comb-tooth electrode parts 14c and 14d are provided at the left end of the The comb-tooth electrode portion 14 a and the comb-tooth electrode portion 14 b are disposed at symmetrical positions with respect to the center position of the mass portion 12 in the Y direction. Similarly, the comb-tooth electrode portion 14 c and the comb-tooth electrode portion 14 d are disposed at symmetrical positions with respect to the center position of the mass portion 12 in the Y direction. The comb-tooth electrode portions 20a, 20b, 20c, and 20d each include a support portion extending in the X direction from the mass portion 12 and an electrode portion extending in the Y direction from the support portion. The plate-like beam portions 16a and 16b are provided at one end (the upper end in FIG. 1) of the mass 12 in the Y direction, and the other end of the mass 12 in the Y direction (FIG. 1) The plate-like beam portions 16c and 16d are provided at the lower end portion thereof. The plate-like beams 16 a, 16 b, 16 c, 16 d extend from the mass 12 along the Y direction and are connected to the peripheral edge 18. The plate-like beam portions 16a, 16b, 16c, and 16d are formed in shapes that have high rigidity in the X direction and Y direction, and low rigidity in the Z direction. When the MEMS sensor 2 is viewed in plan from above, the peripheral portion 18 has the mass 12, the comb-tooth electrodes 14a, 14b, 14c, 14d, the plate-like beams 16a, 16b, 16c, 16d, and the comb-tooth It forms in the rectangular frame shape which encloses electrode part 20a, 20b, 20c, 20d and electrode support part 22a, 22b, 22c, 22d. The lower insulating layer 6 is removed by etching with respect to the mass portion 12, the comb-tooth electrode portions 14 a, 14 b, 14 c, 14 d and the plate-like beam portions 16 a, 16 b, 16 c, 16 d. Relatively displaceable. The peripheral portion 18 is fixed to the support layer 4 via the lower insulating layer 6.

  The comb-tooth electrode portions 20a, 20b, 20c, and 20d are disposed to mesh with the corresponding comb-tooth electrode portions 14a, 14b, 14c, and 14d, respectively. The comb-tooth electrode portions 20a, 20b, 20c, and 20d each include an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The respective electrode portions of the comb-tooth electrode portions 20a, 20b, 20c and 20d are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 14a, 14b, 14c and 14d in the X direction. The support parts of the comb-tooth electrode parts 20a, 20b, 20c, 20d are connected to the corresponding electrode support parts 22a, 22b, 22c, 22d. In the comb-tooth electrode portions 20a, 20b, 20c and 20d, the lower insulating layer 6 is removed by etching, but the electrode support portions 22a, 22b, 22c and 22d are supported on the supporting layer 4 via the lower insulating layer 6. It is fixed against. When the mass portion 12 is not displaced relative to the support layer 4, the Z-direction position of the upper end of the comb electrode portions 14 a, 14 b, 14 c, 14 d is the position of the comb electrode portions 20 a, 20 b, 20 c, 20 d The position in the Z direction of the lower ends of the comb electrode portions 14a, 14b, 14c and 14d corresponds to the position in the Z direction of the upper end, and the position in the Z direction of the lower ends of the comb electrode portions 20a, 20b, 20c and 20d It matches with. The comb-tooth electrode portions 14a, 14b, 14c, 14d and the comb-tooth electrode portions 20a, 20b, 20c, 20d form a parallel plate capacitor. When the comb-tooth electrode portions 14a, 14b, 14c, 14d are displaced relative to the comb-tooth electrode portions 20a, 20b, 20c, 20d in the Z direction, and the opposing area of the both changes, the electrostatic formed between the two The size of the capacity also changes. The change in capacitance can be detected by the arithmetic circuit 11.

  As shown in FIGS. 2 and 3, additional comb-tooth electrodes 24 a and 24 d are provided on the top of the comb-tooth electrode portions 14 a and 14 d. In addition, additional comb electrodes 24 b and 24 c are provided below the comb electrode portions 14 b and 14 c. In the MEMS sensor 2 of the present embodiment, the additional comb-tooth electrodes 24a, 24b, 24c, 24d may be made of any conductive material, for example, the conductive material is imparted. It may be composed of polycrystalline silicon or may be composed of a metal such as aluminum. The additional comb-tooth electrodes 24a, 24b, 24c, 24d are electrically conducted to the corresponding comb-tooth electrodes 14a, 14b, 14c, 14d, respectively.

  The arithmetic circuit 11 is connected to the peripheral portion 18 of the MEMS sensor 2 and the electrode support portions 22a, 22b, 22c, and 22d. The peripheral portion 18 has the same potential as the comb-tooth electrode portions 14a, 14b, 14c, and 14d. Further, the electrode support portions 22a, 22b, 22c, and 22d have the same potential as the comb-tooth electrode portions 20a, 20b, 20c, and 20d, respectively. The arithmetic circuit 11 can detect capacitance between each of the comb-tooth electrode portions 14a, 14b, 14c, 14d and the corresponding comb-tooth electrode portions 20a, 20b, 20c, 20d.

  The operation of the MEMS sensor 2 will be described below. When acceleration in the Z direction acts on the mass portion 12, an inertial force in the Z direction acts on the mass portion 12, and the plate-like beams 16a, 16b, 16c, and 16d are bent and deformed in the Z direction. As a result, the mass portion 12 and the comb electrode portions 14 a, 14 b, 14 c, 14 d are displaced relative to the support layer 4 in the Z direction. The amount of displacement in the Z direction at this time is proportional to the magnitude of the acceleration acting on the mass portion 12. On the other hand, the positions of the comb electrode portions 20 a, 20 b, 20 c and 20 d are fixed with respect to the support layer 4. Therefore, when acceleration in the Z direction acts on the MEMS sensor 2, the comb-tooth electrode portions 14a, 14b, 14c and 14d are displaced relative to the comb-tooth electrode portions 20a, 20b, 20c and 20d in the Z direction. The relative displacement amount in the Z direction at this time has a magnitude corresponding to the acceleration in the Z direction. In the present specification, the comb-tooth electrode portions 14a, 14b, 14c, and 14d relatively displaced with respect to the support layer 4 are also referred to as movable comb-tooth electrodes. Further, the comb-tooth electrode portions 20a, 20b, 20c, and 20d not displaced relative to the support layer 4 are also referred to as fixed comb-tooth electrodes.

  In FIG. 4A, the comb-tooth electrodes 14a and 14c, the additional comb-tooth electrodes 24a and 24c, and the comb-tooth electrode 20a when the mass 12 is not displaced relative to the support layer 4 , 20c are shown. In this state, the comb-tooth electrode portion 14a and the comb-tooth electrode portion 20a completely overlap each other, and the opposing area of the two is equal to the area of the comb-tooth electrode portion 20a. Moreover, in this state, the comb-tooth electrode portion 14c and the comb-tooth electrode portion 20c completely overlap each other, and the opposing area of the two is equal to the area of the comb-tooth electrode portion 20c. In this state, when the arithmetic circuit 11 subtracts the capacitance between the comb electrode portion 14a and the comb electrode portion 20a from the capacitance of the comb electrode portion 14c and the comb electrode portion 20c, the difference is It will be zero.

  As shown in FIG. 4B, when the mass portion 12 is displaced relative to the support layer 4 downward (in the negative direction of the Z direction), the comb-tooth electrode portions 14a and 14c become comb-tooth electrode portions 20a and 20c. Relative to the lower part. In this case, with regard to the comb electrode portion 20a, even if the comb electrode portion 14a is relatively displaced downward, the additional comb electrode 24a provided above the comb electrode portion 14a faces the comb electrode portion 20a. Therefore, the facing area does not change, and the capacitance between the comb-tooth electrode portion 14a and the comb-tooth electrode portion 20a does not change from the state of (a). Unlike this, with respect to the comb-tooth electrode portion 20c, when the comb-tooth electrode portion 14c is relatively displaced downward, the opposing area decreases, and the capacitance between the comb-tooth electrode portion 14c and the comb-tooth electrode portion 20c decreases. Do. In this state, when the arithmetic circuit 11 subtracts the capacitance between the comb electrode portion 14a and the comb electrode portion 20a from the capacitance of the comb electrode portion 14c and the comb electrode portion 20c, the difference is The size is equal to the decrease of the capacitance between the comb-tooth electrode portion 14c and the comb-tooth electrode portion 20c, and the sign of the difference is negative.

  As shown in FIG. 4C, when the mass portion 12 is displaced relative to the support layer 4 upward (in the positive direction of the Z direction), the comb-tooth electrode portions 14a and 14c become comb-tooth electrode portions 20a and 20c. Relative displacement upward with respect to In this case, with respect to the comb electrode portion 20c, even if the comb electrode portion 14c is relatively displaced upward, the additional comb electrode 24c provided below the comb electrode portion 14c faces the comb electrode portion 20c. Therefore, the facing area does not change, and the capacitance between the comb electrode portion 14c and the comb electrode portion 20c does not change from the state of (a). Unlike this, with respect to the comb-tooth electrode portion 20a, when the comb-tooth electrode portion 14a is relatively displaced upward, the opposing area decreases and the capacitance between the comb-tooth electrode portion 14a and the comb-tooth electrode portion 20a decreases. Do. In this state, when the arithmetic circuit 11 subtracts the capacitance between the comb electrode portion 14a and the comb electrode portion 20a from the capacitance of the comb electrode portion 14c and the comb electrode portion 20c, the difference is The size is equal to the decrease in capacitance between the comb-tooth electrode portion 14a and the comb-tooth electrode portion 20a, and the sign of the difference is positive.

  According to the MEMS sensor 2 of the present embodiment, the electrostatic capacitance between the comb electrode portion 14a provided with the additional comb electrode 24a at the upper side and the comb electrode portion 20a and the additional comb electrode 24c provided at the lower side By calculating the difference between the capacitances of the comb electrode portion 14c and the comb electrode portion 20c by using the arithmetic circuit 11, a change in capacitance due to the displacement of the mass portion 12 in the Z direction Only can be detected. In addition, according to the MEMS sensor 2 of the present embodiment, it is determined from the sign of the difference calculated by the arithmetic circuit 11 whether the mass portion 12 is displaced in the positive direction of the Z direction or in the negative direction. be able to. Thereby, the displacement amount of the mass portion 12 in the Z direction can be accurately detected, and the acceleration in the Z direction acting on the mass portion 12 can be accurately detected.

  Hereinafter, a method of manufacturing the MEMS sensor 2 will be described. First, as shown in FIG. 5, a wafer 30 made of single crystal silicon to which conductivity is imparted is prepared. The wafer 30 corresponds to the sensor layer 8.

  Next, as shown in FIG. 6, a silicon oxide layer 32 is formed on the upper surface of the sensor layer 8, and the formed silicon oxide layer 32 is selectively removed by dry etching.

  Next, as shown in FIG. 7, a polycrystalline silicon layer 34 given conductivity is formed on the upper surface of the sensor layer 8, and the formed polycrystalline silicon layer 34 is selectively removed by dry etching. As a result, additional comb-tooth electrodes 24 b and 24 c which are disposed below the comb-tooth electrodes 14 b and 14 c in the MEMS sensor 2 are formed.

  Next, as shown in FIG. 8, the silicon oxide layer 32 on the upper surface of the sensor layer 8 is removed by hydrogen fluoride water or the like.

  Next, as shown in FIG. 9, a wafer 36 made of conductive single crystal silicon is prepared. The wafer 36 corresponds to the support layer 4.

  Next, as shown in FIG. 10, a silicon oxide layer 38 is formed on the upper surface of the support layer 4, and the formed silicon oxide layer 38 is selectively removed by dry etching. The silicon oxide layer 38 corresponds to the insulating layer 6, but the silicon oxide layer 38 at a position corresponding to the mass portion 12 is used as a sacrificial layer. That is, the silicon oxide layer 38 at the position corresponding to the mass portion 12 is not removed at this stage but is removed at the final stage of production.

  Next, as shown in FIG. 11, the sensor layer 8 of FIG. 8 is turned upside down and bonded to the upper surface of the substrate consisting of the support layer 4 and the insulating layer 6 of FIG. 10 (ie, the upper surface of the insulating layer 6). In this state, the upper surface of the sensor layer 8 may be polished to adjust the thickness of the sensor layer 8.

  Next, as shown in FIG. 12, a silicon oxide layer 40 is formed on the upper surface of the sensor layer 8, and the formed silicon oxide layer 40 is selectively removed by dry etching.

  Next, as shown in FIG. 13, a polycrystalline silicon layer 42 given conductivity is formed on the upper surface of the sensor layer 8, and the formed polycrystalline silicon layer 42 is selectively removed by dry etching. As a result, additional comb electrodes 24 a and 24 d are formed above the comb electrodes 14 a and 14 d in the MEMS sensor 2.

  Next, as shown in FIG. 14, the sensor layer 8 is etched away from the upper surface to the lower surface to pattern the sensor layer 8. Thus, the mass portion 12 of the sensor layer 8, the comb-tooth electrodes 14a, 14b, 14c, 14d, the plate-like beams 16a, 16b, 16c, 16d, the peripheral edge 18, and the comb-tooth electrodes 20a, 20b. , 20c, 20d, and electrode support portions 22a, 22b, 22c, 22d.

  Then, the MEMS sensor 2 can be obtained by etching away the insulating layer 6 under the mass part 12 which is a sacrificial layer.

(Example 2)
15 and 16 show the MEMS sensor 102 of this embodiment. Similarly to the MEMS sensor 2 of the first embodiment, the MEMS sensor 102 of the present embodiment mainly includes the support layer 104 made of single crystal silicon to which conductivity is imparted, the insulating layer 106 made of silicon oxide, and conductivity. It is formed on a laminated substrate 110 in which a sensor layer 108 made of applied single crystal silicon is laminated in order. In the following description, the stacking direction of the layered substrate 110 (the direction perpendicular to the plane of FIG. 15, the vertical direction in FIG. 16) is taken as the Z direction, and the in-plane directions of the layered substrate 110 are taken as the X direction and the Y direction. In the following description, the positive direction in the Z direction (the upper direction in FIG. 16) is referred to as the upper direction, and the negative direction in the Z direction (the lower direction in FIG. 16) is referred to as the downward direction. In the MEMS sensor 102 of this embodiment, the insulating layer 106 is stacked above the support layer 104, and the sensor layer 108 is stacked above the insulating layer 106. The MEMS sensor 102 is used in combination with the arithmetic circuit 111.

  In the sensor layer 108, by selectively removing single crystal silicon by etching, the mass portion 112, the comb-tooth electrode portions 114a and 114b, the plate-like beam portions 116a, 116b, 116c and 116d, and the relay portion 118a. , 118b, straight beam portions 120a, 120b, 120c, 120d, relay support portions 122a, 122b, 122c, 122d, comb electrode portions 124a, 124b, comb electrode portions 126a, 126b, detection electrode support portion 128a and 128b, comb-tooth electrode parts 130a and 130b, and excitation electrode support parts 132a and 132b are formed. Among them, the mass portion 112, the comb electrode portions 114a and 114b, the plate-like beam portions 116a, 116b, 116c and 116d, the relay portions 118a and 118b, the straight beam portions 120a, 120b, 120c and 120d, and the relay The support portions 122a, 122b, 122c, 122d and the comb-tooth electrode portions 124a, 124b are integrally formed seamlessly, and they are maintained at the same potential. In addition, the comb-tooth electrode portions 126a and 126b are integrally formed seamlessly with the corresponding detection electrode support portions 128a and 128b, respectively, and are maintained at the same potential. Further, the comb-tooth electrode portions 130a and 130b are integrally formed seamlessly with the corresponding excitation electrode support portions 132a and 132b, respectively, and are maintained at the same potential.

  The mass portion 112 is formed in a rectangular shape when the MEMS sensor 102 is viewed in plan from above. The comb-tooth electrode portion 114a is provided at one end (the end on the left side in FIG. 15) of the mass portion 112 in the X direction, and the other end (the right side in FIG. 15) of the mass portion 112 in the X direction. The comb-tooth electrode portion 114 b is provided at the end portion of the The comb-tooth electrode portions 114 a and 114 b are disposed at the center position of the mass portion 112 in the Y direction. Each of the comb-tooth electrode parts 114 a and 114 b includes a support part extending in the X direction from the mass part 112 and an electrode part extending in the Y direction from the support part. The plate-like beam portions 116a and 116b are provided at one end (the upper end in FIG. 15) of the mass portion 112 in the Y direction, and the other end (FIG. 15) of the mass portion 112 in the Y direction. The plate-like beam portions 116c and 116d are provided at the lower end portion thereof. The plate-like beam portions 116a and 116b extend from the mass portion 112 in the Y direction and are connected to the relay portion 118a. The plate-like beam portions 116c and 116d respectively extend from the mass portion 112 in the Y direction and are connected to the relay portion 118b. The plate-like beam portions 116a, 116b, 116c, and 116d are formed in shapes that have high rigidity in the X direction and Y direction, and low rigidity in the Z direction. The relay portions 118 a and 118 b are formed in a rectangular shape having a longitudinal direction in the X direction when the MEMS sensor 102 is viewed in plan from above. One end (the end on the left side in FIG. 15) of the relay portion 118a in the X direction is connected to the relay support portion 122a via the linear beam portion 120a. The other end (the end on the right side in FIG. 15) of the relay portion 118a in the X direction is connected to the relay support portion 122b via the linear beam portion 120b. A comb electrode portion 124 a extending along the Y direction is provided at an end portion of the relay portion 118 a in the Y direction. One end (the end on the left side in FIG. 15) of the relay portion 118b in the X direction is connected to the relay support portion 122c via the linear beam portion 120c. The other end (the end on the right side in FIG. 15) of the relay portion 118b in the X direction is connected to the relay support portion 122d via the linear beam portion 120d. A comb-tooth electrode portion 124b extending along the Y direction is provided at an end of the relay portion 118b in the Y direction. The straight beam portions 120a, 120b, 120c, and 120d are formed in shapes that have high rigidity in the X and Z directions and low rigidity in the Y direction. Mass portion 112, comb-tooth electrode portions 114a and 114b, plate-like beam portions 116a, 116b, 116c and 116d, relay portions 118a and 118b, straight beam portions 120a, 120b, 120c and 120d, comb-tooth electrode portion The lower insulating layer 106 is removed by etching and 124a and 124b are displaceable relative to the support layer 104. The relay support portions 122 a, 122 b, 122 c, 122 d are fixed to the support layer 104 via the lower insulating layer 106.

  The comb-tooth electrode portions 126a and 126b are respectively arranged to mesh with the corresponding comb-tooth electrode portions 114a and 114b. Each of the comb-tooth electrode portions 126a and 126b includes an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The respective electrode portions of the comb-tooth electrode portions 126a and 126b are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 114a and 114b in the X direction. The support portions of the comb-tooth electrode portions 126a and 126b are connected to the corresponding detection electrode support portions 128a and 128b. Although the lower insulating layer 106 is removed by etching the comb electrode portions 126a and 126b, the detection electrode support portions 128a and 128b are fixed to the support layer 104 via the lower insulating layer 106. . When the mass portion 112 is not displaced relative to the support layer 104, the Z-direction position of the upper end of the comb-tooth electrode portions 114a and 114b is equal to the Z-direction position of the upper end of the comb-tooth electrode portions 126a and 126b. The position in the Z direction of the lower end of the comb electrode portions 114a and 114b is the same as the position in the Z direction of the lower end of the comb electrode portions 126a and 126b. The comb-tooth electrode portions 114a and 114b and the comb-tooth electrode portions 126a and 126b form a parallel plate capacitor. When the comb-tooth electrode parts 114a and 114b are relatively displaced in the Z direction with respect to the comb-tooth electrode parts 126a and 126b, and the opposing area of the two changes, the magnitude of the capacitance formed between the two also changes. The change in capacitance can be detected by the arithmetic circuit 111.

  The comb-tooth electrode portions 130a and 130b are disposed to mesh with the corresponding comb-tooth electrode portions 124a and 124b. The comb-tooth electrode portions 130a and 130b extend in the Y direction, and are arranged to face the corresponding comb-tooth electrode portions 124a and 124b in the X direction. The comb-tooth electrode portions 130a and 130b are connected to the corresponding excitation electrode support portions 132a and 132b, respectively. In the comb-tooth electrode portions 130a and 130b, the lower insulating layer 106 is removed by etching, but the excitation electrode supporting portions 132a and 132b are fixed to the support layer 104 via the lower insulating layer 106. . The position in the Z direction of the upper end of the comb electrode portions 124a and 124b coincides with the position in the Z direction of the upper end of the comb electrode portions 130a and 130b, and the position in the Z direction of the lower end of the comb electrode portions 124a and 124b Is the same as the position of the lower end of the comb electrode portions 130a and 130b in the Z direction. The comb-tooth electrode portions 124a and 124b and the corresponding comb-tooth electrode portions 130a and 130b form a parallel plate capacitor. When a voltage is applied between the comb-tooth electrode portions 124a and 124b and the corresponding comb-tooth electrode portions 130a and 130b, the comb-tooth electrode portions 124a and 124b correspond to the corresponding comb-tooth electrode portions so as to increase their opposing areas. Electrostatic attraction acts to pull in 130a, 130b.

  As shown in FIG. 16, an additional comb electrode 134a is provided below the comb electrode portion 114a. Further, an additional comb electrode 134 b is provided on the upper side of the comb electrode portion 114 b. The additional comb-tooth electrodes 134a and 134b may be made of any conductive material, for example, may be made of polycrystalline silicon to which conductivity is imparted, or aluminum Etc. may be comprised from metals, such as. The additional comb electrodes 134a and 134b are electrically conducted to the corresponding comb electrode portions 114a and 114b, respectively.

  The arithmetic circuit 111 is connected to the relay support portion 122d of the MEMS sensor 102, the excitation electrode support portions 132a and 132b, and the detection electrode support portions 128a and 128b. The relay support portion 122d has the same potential as the comb-tooth electrode portions 114a and 114b and the comb-tooth electrode portions 124a and 124b. The excitation electrode support portions 132a and 132b have the same potential as the comb electrode portions 130a and 130b, respectively, and the detection electrode support portions 128a and 128b have the same potential as the comb electrode portions 126a and 126b, respectively. The arithmetic circuit 111 can apply a voltage between each of the comb electrode portions 124a and 124b and the corresponding comb electrode portions 130a and 130b, and corresponds to each of the comb electrode portions 114a and 114b. The electrostatic capacitance between the comb-tooth electrode parts 126a and 126b can be detected.

  The operation of the MEMS sensor 102 will be described below. When a voltage is applied between the comb-tooth electrode portion 124a and the comb-tooth electrode portion 130a, electrostatic attraction is exerted to pull the comb-tooth electrode portion 124a to the comb-tooth electrode portion 130a, and the relay portion 118a and the plate-like beam The portions 116a and 116b, the mass portion 112, the plate-like beams 116c and 116d, and the relay portion 118b are integrally displaced upward in FIG. Conversely, when a voltage is applied between the comb-tooth electrode portion 124 b and the comb-tooth electrode portion 130 b, an electrostatic attractive force is exerted to pull the comb-tooth electrode portion 124 b into the comb-tooth electrode portion 130 b, and the relay portion 118 b The plate-like beam portions 116c and 116d, the mass portion 112, the plate-like beam portions 116a and 116b, and the relay portion 118a are integrally displaced downward in FIG. By alternately applying such a voltage, the mass portion 112 is excited in the Y direction.

  When an angular velocity around the X axis acts on the MEMS sensor 102 while the mass portion 112 vibrates in the Y direction, Coriolis force in the Z direction acts on the mass portion 112, and the mass portion 112 vibrates in the Z direction Do. The amplitude of the Z-direction vibration of the mass portion 112 at this time is proportional to the magnitude of the angular velocity around the X axis acting on the MEMS sensor 102. When the mass portion 112 vibrates in the Z direction, the comb electrode portions 114a and 114b vibrate in the Z direction (vertical direction in FIG. 16) with respect to the comb electrode portions 126a and 126b. The arithmetic circuit 111 detects the electrostatic capacitance between the comb-tooth electrode portions 114 a and 114 b and the corresponding comb-tooth electrode portions 126 a and 126 b, and calculates the difference between the two, thereby acting on the MEMS sensor 102. An angular velocity around an axis can be detected.

  Similar to the MEMS sensor 2 of the first embodiment, according to the MEMS sensor 102 of the present embodiment, the capacitance between the comb electrode portion 114 b and the comb electrode portion 126 b provided with the additional comb electrode 134 b above The Z value of the mass portion 112 is calculated by the calculation circuit 111 by calculating the difference between the capacitances of the comb electrode portion 114a and the comb electrode portion 126a provided with the additional comb electrode 134a below. Only changes in capacitance due to directional displacement can be detected. In addition, according to the MEMS sensor 102 of the present embodiment, it is detected from the sign of the difference calculated by the arithmetic circuit 111 whether the mass portion 112 is displaced in the positive direction of the Z direction or in the negative direction. be able to. As a result, the displacement amount of the mass portion 112 in the Z direction can be accurately detected, and the angular velocity around the X axis acting on the mass portion 112 can be accurately detected.

(Example 3)
FIGS. 17-19 show the MEMS sensor 202 of this embodiment. The MEMS sensor 202 is provided with conductivity by a support layer 204 made of single crystal silicon which has been imparted conductivity by n-type impurity doping, an insulating layer 206 made of silicon oxide, and mainly by n-type impurity doping. The sensor layer 208 made of single crystal silicon is formed on the laminated substrate 210 in order. In the following description, the stacking direction of the layered substrate 210 (the direction perpendicular to the sheet of FIG. 17, the vertical direction of FIGS. 18 and 19) is taken as the Z direction, and the in-plane direction of the layered substrate 210 is taken as the X direction and the Y direction. In the following description, the positive direction in the Z direction (upper direction in FIGS. 17 and 18) is referred to as the upper direction, and the negative direction in the Z direction (lower direction in FIGS. 17 and 18) is referred to as the downward direction. In the MEMS sensor 202 of this embodiment, the insulating layer 206 is stacked above the support layer 204, and the sensor layer 208 is stacked above the insulating layer 206. The MEMS sensor 202 is used in combination with the arithmetic circuit 211.

  In the sensor layer 208, by selectively removing single crystal silicon by etching, the mass portion 212, the comb-tooth electrode portions 214a, 214b, 214c and 214d, and the plate-like beam portions 216a, 216b, 216c and 216d and The peripheral portion 218, the comb-tooth electrode portions 220a, 220b, 220c, and 220d, and the electrode support portions 222a, 222b, 222c, and 222d are formed. Among them, the mass portion 212, the comb-tooth electrode portions 214a, 214b, 214c and 214d, the plate-like beam portions 216a, 216b, 216c and 216d and the peripheral portion 218 are integrally formed seamlessly. Is maintained at the same potential. Further, the comb-tooth electrode portions 220a, 220b, 220c, and 220d are integrally formed seamlessly with the corresponding electrode support portions 222a, 222b, 222c, and 222d, respectively, and are maintained at the same potential.

  The mass portion 212 is formed in a rectangular shape when the MEMS sensor 202 is viewed in plan from above. The comb electrode portions 214a and 214b are provided at one end (the end on the right side of FIG. 17) of the mass 212 in the X direction, and the other end of the mass 212 in the X direction (FIG. 17). The comb-tooth electrode parts 214c and 214d are provided at the left end of the The comb-tooth electrode portion 214 a and the comb-tooth electrode portion 214 b are disposed at symmetrical positions with respect to the center position of the mass portion 212 in the Y direction. Similarly, the comb-tooth electrode portion 214 c and the comb-tooth electrode portion 214 d are disposed at symmetrical positions with respect to the center position of the mass portion 212 in the Y direction. The comb-tooth electrode portions 220a, 220b, 220c, and 220d each include a support portion extending in the X direction from the mass portion 212 and an electrode portion extending in the Y direction from the support portion. The plate-like beams 216a and 216b are provided at one end (the upper end in FIG. 17) of the mass 212 in the Y direction, and the other end (Y in FIG. 17) of the mass 212 is provided. The plate-like beam portions 216c and 216d are provided at the lower end portion thereof. The plate-like beams 216 a, 216 b, 216 c, and 216 d extend from the mass 212 along the Y direction and are connected to the peripheral edge 218. The plate-like beam portions 216a, 216b, 216c, and 216d are formed in shapes that have high rigidity in the X direction and Y direction, and low rigidity in the Z direction. When the MEMS sensor 202 is viewed in plan from above, the peripheral portion 218 has the mass portion 212, the comb-tooth electrodes 214a, 214b, 214c and 214d, the plate-like beams 216a, 216b, 216c and 216d, and the comb-tooth It is formed in a rectangular frame shape surrounding the electrode portions 220a, 220b, 220c, 220d and the electrode support portions 222a, 222b, 222c, 222d. The lower insulating layer 206 is removed by etching with respect to the mass portion 212, the comb-tooth electrode portions 214a, 214b, 214c, and 214d, and the plate-like beam portions 216a, 216b, 216c, and 216d. Relatively displaceable. The peripheral portion 218 is fixed to the support layer 204 via the lower insulating layer 206.

  The comb-tooth electrode portions 220a, 220b, 220c, and 220d are disposed to mesh with the corresponding comb-tooth electrode portions 214a, 214b, 214c, and 214d, respectively. The comb-tooth electrode portions 220a, 220b, 220c, and 220d respectively include an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The electrode portions of the comb-tooth electrode portions 220a, 220b, 220c, and 220d are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 214a, 214b, 214c, and 214d in the X direction. The support portions of the comb-tooth electrode portions 220a, 220b, 220c, and 220d are connected to the corresponding electrode support portions 222a, 222b, 222c, and 222d. Although the lower insulating layer 206 is removed by etching the comb electrode portions 220a, 220b, 220c and 220d, the electrode support portions 222a, 222b, 222c and 222d are supported by the support layer 204 via the lower insulating layer 206. It is fixed against. When the mass portion 212 is not displaced relative to the support layer 204, the Z-direction position of the upper end of the comb electrode portions 214a, 214b, 214c, and 214d is the position of the comb electrode portions 220a, 220b, 220c, and 220d. The position in the Z direction of the lower end of the comb electrode portions 214a, 214b, 214c, 214d coincides with the position in the Z direction of the upper end, the position in the Z direction of the lower end of the comb electrode portions 220a, 220b, 220c, 220d It matches with.

  As shown in FIGS. 18 and 19, additional comb electrodes 224 a and 224 d are provided above the comb electrode portions 214 a and 214 d. Further, additional comb electrodes 224 b and 224 c are provided below the comb electrode portions 214 b and 214 c. In the MEMS sensor 202 according to this embodiment, the additional comb-tooth electrodes 224a, 224b, 224c, and 224d are made of polycrystalline silicon to which conductivity is imparted by doping of p-type impurities. The additional comb-tooth electrodes 224a, 224b, 224c and 224d are connected to the corresponding comb-tooth electrodes 214a, 214b, 214c and 214d via pn junctions, and the corresponding comb-tooth electrodes 214a, 214b, 214c, Electrically isolated from 214d.

  As shown in FIG. 17, the additional comb-tooth electrodes 224 a and 224 d are electrically connected via a relay wiring 226 a provided on the top surface of the mass portion 212. The additional comb electrode 224 d is electrically conducted to the pad portion 230 a provided on the upper surface of the peripheral portion 218 through the relay portion 228 a provided on the upper surface of the mass portion 212, the plate-like beam portion 216 c and the peripheral portion 218. doing. The additional comb-tooth electrodes 224 b and 224 c are electrically connected via the relay wiring 226 b provided on the lower surface of the mass portion 212. The additional comb electrode 224 b is a peripheral edge portion through the through electrode 232 penetrating the mass portion 212 from the upper surface to the lower surface, and the relay wiring 228 b provided on the upper surface of the mass portion 212, the plate-like beam portion 216 d and the peripheral portion 218. It electrically conducts to the pad part 230b provided in the upper surface of 218. FIG. The relay interconnections 226a and 226b, the relay interconnections 228a and 228b, the pad portions 230a and 230b, and the through electrodes 232 are all made of polycrystalline silicon to which conductivity is imparted by doping of p-type impurities. The relay wires 226a and 226b, the relay wires 228a and 228b, the pad portions 230a and 230b, and the through electrodes 232 are connected to the mass portion 212, the plate-like beam portions 216c and 216d, and the peripheral portion 218 via a pn junction. It electrically insulates from the part 212, the plate-like beams 216c and 216d, and the peripheral part 218.

  The arithmetic circuit 211 is connected to the electrode support portions 222 a, 222 b, 222 c, 222 d and the pad portions 230 a, 230 b of the MEMS sensor 202. The electrode support portions 222a, 222b, 222c, and 222d have the same potential as the comb-tooth electrode portions 220a, 220b, 220c, and 220d, respectively. The pad portion 230a is at the same potential as the additional comb electrodes 224a and 224d, and the pad portion 230b is at the same potential as the additional comb electrodes 224b and 224c. The arithmetic circuit 211 can detect the capacitance between each of the additional comb electrodes 224a, 224b, 224c, and 224d and the corresponding comb electrode portions 220a, 220b, 220c, and 220d.

  The operation of the MEMS sensor 202 will be described below. When an acceleration in the Z direction acts on the mass portion 212, an inertial force in the Z direction acts on the mass portion 212, and the plate beams 216a, 216b, 216c, and 216d are bent and deformed in the Z direction. As a result, the mass portion 212 and the comb-tooth electrode portions 214 a, 214 b, 214 c, 214 d are displaced relative to the support layer 204 in the Z direction. The amount of displacement in the Z direction at this time is proportional to the magnitude of the acceleration acting on the mass portion 212. On the other hand, the positions of the comb electrode portions 220 a, 220 b, 220 c and 220 d are fixed with respect to the support layer 204. Therefore, when acceleration in the Z direction acts on the MEMS sensor 202, the comb-tooth electrode portions 214a, 214b, 214c and 214d are displaced relative to the comb-tooth electrode portions 220a, 220b, 220c and 220d in the Z direction. The relative displacement amount in the Z direction at this time has a magnitude corresponding to the acceleration in the Z direction.

  In (a) of FIG. 20, the comb-tooth electrode portions 214a and 214c, the additional comb-tooth electrodes 224a and 224c, and the comb-tooth electrode portion 220a in a state in which the mass portion 212 is not displaced relative to the support layer 204. , 220c are shown. In this state, the comb-tooth electrode portion 214a and the comb-tooth electrode portion 220a completely overlap each other, the additional comb-tooth electrode 224a does not face the comb-tooth electrode portion 220a, and the capacitance between both is substantially zero. It is. Further, in this state, the comb-tooth electrode portion 214c and the comb-tooth electrode portion 220c completely overlap each other, the additional comb-tooth electrode 224c does not face the comb-tooth electrode portion 220c, and the capacitance between both is It is almost zero. In this state, when the arithmetic circuit 211 subtracts the capacitance between the additional comb electrode 224 a and the comb electrode portion 220 a from the capacitance of the additional comb electrode 224 c and the comb electrode portion 220 c, the difference is It will be zero.

  As shown in (b) of FIG. 20, when the mass portion 212 is displaced relative to the support layer 204 downward (in the negative direction of the Z direction), the comb-tooth electrode portions 214a and 214c become comb-tooth electrode portions 220a and 220c. Relative to the lower part. In this case, the comb electrode portion 220a is opposed to the additional comb electrode 224a, and the capacitance between the additional comb electrode 224a and the comb electrode portion 220a is smaller than in the state of (a). To increase. Unlike this, the comb electrode portion 220c does not still face the additional comb electrode 224c, so the capacitance between the additional comb electrode 224c and the comb electrode portion 220c remains zero. When the arithmetic circuit 211 subtracts the capacitance between the additional comb electrode 224 a and the comb electrode portion 220 a from the capacitance of the additional comb electrode 224 c and the comb electrode portion 220 c in the state of (b), The magnitude of the difference is equal to the increase in capacitance between the additional comb electrode 224 a and the comb electrode portion 220 a, and the sign of the difference is negative.

  As shown in (c) of FIG. 20, when the mass portion 212 is relatively displaced upward (in the positive direction of the Z direction) with respect to the support layer 204, the comb electrode portions 214a and 214c become comb electrode portions 220a and 220c. Relative displacement upward with respect to In this case, the comb electrode portion 220c is opposed to the additional comb electrode 224c, and the capacitance between the additional comb electrode 224c and the comb electrode portion 220c is smaller than in the state of (a). To increase. Unlike this, with regard to the comb electrode portion 220a, since it does not still face the additional comb electrode 224a, the capacitance between the additional comb electrode 224a and the comb electrode portion 220a remains zero. In state (c), when the arithmetic circuit 211 subtracts the capacitance between the additional comb electrode 224 a and the comb electrode portion 220 a from the capacitance of the additional comb electrode 224 c and the comb electrode portion 220 c, The magnitude of the difference is equal to the increase in capacitance between the additional comb electrode 224 c and the comb electrode portion 220 c, and the sign of the difference is positive.

  According to the MEMS sensor 202 of the present embodiment, the capacitance between the additional comb electrode 224 a provided above the comb electrode portion 214 a and the comb electrode portion 220 a and the capacitance provided below the comb electrode portion 214 c Change of the capacitance due to the displacement of the mass portion 212 in the Z direction by calculating the difference between the capacitance between the added additional comb electrode 224c and the comb electrode portion 220c by the arithmetic circuit 211 Can be detected. In addition, according to the MEMS sensor 202 of this embodiment, it is detected from the sign of the difference calculated by the arithmetic circuit 211 whether the mass portion 212 is displaced in the positive direction of the Z direction or in the negative direction. be able to. Thereby, the displacement amount of the mass portion 212 in the Z direction can be detected with high accuracy, and the acceleration in the Z direction acting on the mass portion 212 can be detected with high accuracy.

  The MEMS sensor 202 of this embodiment can be manufactured by the same manufacturing method as that of the MEMS sensor 2 of the first embodiment except that the through electrode 232 is formed, and thus the detailed description of the manufacturing method is omitted.

(Example 4)
21-23 show a MEMS sensor 302 of this embodiment. In the MEMS sensor 302, a support layer 304 made of conductive single crystal silicon, an insulating layer 306 made of silicon oxide, and a sensor layer 308 mainly made of conductive single crystal silicon are sequentially stacked. Also, it is formed on the laminated substrate 310. In the following description, the stacking direction of the layered substrate 310 (the direction perpendicular to the sheet of FIG. 21, the vertical direction of FIGS. 22 and 23) is taken as the Z direction, and the in-plane direction of the layered substrate 310 is taken as the X direction and the Y direction. Further, in the following description, the positive direction in the Z direction (upper direction in FIGS. 22 and 23) is referred to as the upper direction, and the negative direction in the Z direction (lower direction in FIGS. 22 and 23) is referred to as the downward direction. In the MEMS sensor 302 according to this embodiment, the insulating layer 306 is stacked above the support layer 304, and the sensor layer 308 is stacked above the insulating layer 306. The MEMS sensor 302 is used in combination with the arithmetic circuit 311.

  In the sensor layer 308, by selectively removing single crystal silicon by etching, the mass portion 312, the comb-tooth electrode portions 314a, 314b, 314c, 314d, and the plate-like beam portions 316a, 316b, 316c, 316d and The peripheral portion 318, the comb-tooth electrode portions 320a, 320b, 320c, and 320d, and the electrode support portions 322a, 322b, 322c, and 322d are formed. Among them, the mass portion 312, the comb-tooth electrode portions 314a, 314b, 314c, 314d, the plate-like beam portions 316a, 316b, 316c, 316d, and the peripheral portion 318 are integrally formed seamlessly. Is maintained at the same potential. In addition, the comb-tooth electrode portions 320a, 320b, 320c, and 320d are integrally formed seamlessly with the corresponding electrode support portions 322a, 322b, 322c, and 322d, respectively, and are maintained at the same potential.

  The mass portion 312 is formed in a rectangular shape when the MEMS sensor 302 is viewed in plan from above. The comb-like electrode portions 314a and 314b are provided at one end of the mass portion 312 in the X direction (the end on the right side of FIG. 21), and the other end of the mass portion 312 in the X direction (FIG. 21) The comb-tooth electrode parts 314 c and 314 d are provided at the left end of the The comb-tooth electrode portion 314 a and the comb-tooth electrode portion 314 b are disposed at symmetrical positions with respect to the center position of the mass portion 312 in the Y direction. Similarly, the comb-tooth electrode portion 314 c and the comb-tooth electrode portion 314 d are disposed at symmetrical positions with respect to the center position of the mass portion 312 in the Y direction. The comb-tooth electrode portions 320a, 320b, 320c, and 320d each include a support portion extending from the mass portion 312 in the X direction, and an electrode portion extending from the support portion in the Y direction. Plate-like beam portions 316a and 316b are provided at one end (the upper end in FIG. 21) of the mass portion 312 in the Y direction, and the other end (FIG. 21) of the mass portion 312 in the Y direction. The plate-like beam portions 316 c and 316 d are provided at the lower end portion thereof. The plate-shaped beam portions 316 a, 316 b, 316 c, and 316 d extend from the mass portion 312 along the Y direction and are connected to the peripheral portion 318. The plate-like beam portions 316a, 316b, 316c, and 316d are formed in shapes that have high rigidity in the X direction and Y direction, and low rigidity in the Z direction. The peripheral portion 318 has the mass portion 312, the comb-tooth electrode portions 314a, 314b, 314c, and 314d, the plate-like beam portions 316a, 316b, 316c, and 316d, and the comb-tooth portions when the MEMS sensor 302 is viewed in plan from above. It forms in the rectangular frame shape which encloses electrode part 320a, 320b, 320c, 320d and electrode support part 322a, 322b, 322c, 322d. In the mass portion 312, the comb-tooth electrode portions 314a, 314b, 314c, and 314d, and the plate-like beam portions 316a, 316b, 316c, and 316d, the lower insulating layer 306 is removed by etching. Relatively displaceable. The peripheral portion 318 is fixed to the support layer 304 via the lower insulating layer 306.

  The comb-tooth electrode portions 320a, 320b, 320c, and 320d are arranged to mesh with the corresponding comb-tooth electrode portions 314a, 314b, 314c, and 314d, respectively. The comb-tooth electrode portions 320a, 320b, 320c, and 320d respectively include an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The electrode portions of the comb-tooth electrode portions 320a, 320b, 320c, and 320d are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 314a, 314b, 314c, and 314d in the X direction. The support portions of the comb-tooth electrode portions 320a, 320b, 320c, and 320d are connected to the corresponding electrode support portions 322a, 322b, 322c, and 322d. Although the lower insulating layer 306 is removed by etching the comb-tooth electrode portions 320a, 320b, 320c, and 320d, the electrode support portions 322a, 322b, 322c, and 322d are supported by the support layer 304 via the lower insulating layer 306. It is fixed against. When the mass portion 312 is not displaced relative to the support layer 304, the Z-direction position of the upper end of the comb electrode portions 314a, 314b, 314c, and 314d is the position of the comb electrode portions 320a, 320b, 320c, and 320d. The position in the Z direction of the lower end of the comb electrode portions 314a, 314b, 314c, 314d corresponds to the position in the Z direction of the upper end in the Z direction of the lower end of the comb electrode portions 320a, 320b, 320c, 320d It matches with.

  As shown in FIGS. 22 and 23, additional comb electrodes 324a and 324d are provided on the top of the comb electrode portions 314a and 314d. Further, additional comb-teeth electrodes 324 b and 324 c are provided below the comb-teeth electrode portions 314 b and 314 c. In the MEMS sensor 302 according to the present embodiment, the additional comb-teeth electrodes 324a, 324b, 324c, and 324d may be made of any conductive material, and may be made of any conductive polycrystalline material. It may be composed of silicon or may be composed of a metal such as aluminum. The additional comb-teeth electrodes 324a, 324b, 324c, and 324d are connected to the corresponding comb-teeth electrode parts 314a, 314b, 314c, and 314d via the insulating films 334a, 334b, 334c, and 334d, respectively. It electrically insulates from electrode part 314a, 314b, 314c, 314d.

  As shown in FIG. 21, the additional comb-teeth electrodes 324 a and 324 d are electrically conducted via a relay wiring 326 a provided on the top surface of the mass portion 312. The additional comb electrode 324 d is electrically conducted to the pad portion 330 a provided on the upper surface of the peripheral portion 318 through the relay portion 328 a provided on the upper surface of the mass portion 312, the plate beam portion 316 c and the peripheral portion 318. doing. The additional comb-teeth electrodes 324 b and 324 c are electrically connected via a relay wire 326 b provided on the lower surface of the mass portion 312. The additional comb electrode 324b is a peripheral edge portion through the through electrode 332 penetrating the mass portion 312 from the upper surface to the lower surface, and the relay wiring 328b provided on the upper surface of the mass portion 312, the plate beam portion 316d and the peripheral portion 318. It electrically conducts to the pad part 330b provided in the upper surface of 318. FIG. Relay wires 326a and 326b, relay wires 328a and 328b, pad portions 330a and 330b, and through electrodes 332 may be made of any conductive material, and can be made conductive. It may be composed of the polycrystalline silicon as it is, or it may be composed of a metal such as aluminum. The relay wires 326a and 326b, the relay wires 328a and 328b, the pad portions 330a and 330b, and the through electrode 332 are connected to the mass portion 312, the plate-like beams 316c and 316d, and the peripheral portion 318 via the insulating film 336. , The mass portion 312, the plate-like beams 316c and 316d, and the peripheral portion 318.

  The arithmetic circuit 311 is connected to the electrode support portions 322 a, 322 b, 322 c, 322 d of the MEMS sensor 302 and the pad portions 330 a, 330 b. The electrode support portions 322a, 322b, 322c, and 322d have the same potential as the comb-tooth electrode portions 320a, 320b, 320c, and 320d, respectively. The pad portion 330a has the same potential as the additional comb electrodes 324a and 324d, and the pad portion 330b has the same potential as the additional comb electrodes 324b and 324c. The arithmetic circuit 311 can detect capacitance between each of the additional comb electrodes 324a, 324b, 324c, and 324d and the corresponding comb electrode units 320a, 320b, 320c, and 320d.

  The operation of the MEMS sensor 302 will be described below. When an acceleration in the Z direction acts on the mass portion 312, an inertial force in the Z direction acts on the mass portion 312, and the plate beams 316a, 316b, 316c, and 316d are bent and deformed in the Z direction. As a result, the mass portion 312 and the comb-tooth electrode portions 314 a, 314 b, 314 c, 314 d are displaced relative to the support layer 304 in the Z direction. The amount of displacement in the Z direction at this time is proportional to the magnitude of the acceleration acting on the mass portion 312. On the other hand, the positions of the comb electrode portions 320 a, 320 b, 320 c and 320 d are fixed with respect to the support layer 304. Therefore, when acceleration in the Z direction acts on the MEMS sensor 302, the comb-tooth electrode portions 314a, 314b, 314c and 314d are displaced relative to the comb-tooth electrode portions 320a, 320b, 320c and 320d in the Z direction. The relative displacement amount in the Z direction at this time has a magnitude corresponding to the acceleration in the Z direction.

  In (a) of FIG. 24, the comb-tooth electrode portions 314a and 314c, the additional comb-tooth electrodes 324a and 324c, and the comb-tooth electrode portion 320a in a state where the mass portion 312 is not displaced relative to the support layer 304. , 320c are shown. In this state, the comb-tooth electrode portion 314a and the comb-tooth electrode portion 320a completely overlap each other, the additional comb-tooth electrode 324a does not face the comb-tooth electrode portion 320a, and the capacitance between both is substantially zero. It is. Further, in this state, the comb-tooth electrode portion 314c and the comb-tooth electrode portion 320c completely overlap each other, the additional comb-tooth electrode 324c does not face the comb-tooth electrode portion 320c, and the capacitance between both is It is almost zero. In this state, when the arithmetic circuit 311 subtracts the capacitance between the additional comb electrode 324a and the comb electrode portion 320a from the capacitance of the additional comb electrode 324c and the comb electrode portion 320c, the difference is It will be zero.

  As shown in (b) of FIG. 24, when the mass portion 312 is displaced relative to the support layer 304 downward (in the negative direction of the Z direction), the comb-tooth electrode portions 314 a, 314 c become comb-tooth electrode portions 320 a, 320 c. Relative to the lower part. In this case, the comb electrode portion 320a is opposed to the additional comb electrode 324a, and the capacitance between the additional comb electrode 324a and the comb electrode portion 320a is smaller than that in the state of (a). To increase. Unlike this, with regard to the comb-tooth electrode portion 320c, the capacitance between the additional comb-tooth electrode 324c and the comb-tooth electrode portion 320c remains zero, because it does not yet face the additional comb-tooth electrode 324c. When the arithmetic circuit 311 subtracts the capacitance between the additional comb electrode 324 a and the comb electrode portion 320 a from the capacitance of the additional comb electrode 324 c and the comb electrode portion 320 c in the state of (b), The magnitude of the difference is equal to the increase in capacitance between the additional comb electrode 324 a and the comb electrode portion 320 a, and the sign of the difference is negative.

  As shown in FIG. 24C, when the mass portion 312 is displaced relative to the support layer 304 upward (in the positive direction of the Z direction), the comb-tooth electrode portions 314a and 314c become comb-tooth electrode portions 320a and 320c. Relative displacement upward with respect to In this case, the comb electrode portion 320c is opposed to the additional comb electrode 324c, and the capacitance between the additional comb electrode 324c and the comb electrode portion 320c is smaller than that in the state of (a). To increase. Unlike this, with regard to the comb electrode portion 320a, since it does not still face the additional comb electrode 324a, the capacitance between the additional comb electrode 324a and the comb electrode portion 320a remains zero. When the arithmetic circuit 311 subtracts the capacitance between the additional comb electrode 324 a and the comb electrode portion 320 a from the capacitance of the additional comb electrode 324 c and the comb electrode portion 320 c in the state of (c), The magnitude of the difference is equal to the increase in capacitance between the additional comb electrode 324 c and the comb electrode portion 320 c, and the sign of the difference is positive.

  According to the MEMS sensor 302 of this embodiment, the capacitance between the additional comb electrode 324 a and the comb electrode 320 a provided above the comb electrode 314 a and the capacitance between the additional electrode 314 a and the comb electrode 314 c are provided. Change of the capacitance due to the displacement of the mass portion 312 in the Z direction by calculating the difference between the capacitance between the added additional comb electrode 324c and the comb electrode portion 320c by the arithmetic circuit 311 Can be detected. In addition, according to the MEMS sensor 302 of this embodiment, it is detected from the sign of the difference calculated by the arithmetic circuit 311 whether the mass part 312 is displaced in the positive direction of the Z direction or in the negative direction. be able to. By this, the displacement amount of the mass portion 312 in the Z direction can be detected with high accuracy, and the acceleration in the Z direction acting on the mass portion 312 can be detected with high accuracy.

  Hereinafter, a method of manufacturing the MEMS sensor 302 will be described. First, as shown in FIG. 25, a wafer 340 made of conductive single crystal silicon is prepared. The wafer 340 corresponds to the sensor layer 308.

  Next, as shown in FIG. 26, after etching the portion corresponding to the through electrode 332 of the sensor layer 308 from the upper surface, the silicon oxide layer 342 is formed on the upper surface of the sensor layer 308.

  Next, as shown in FIG. 27, a conductive polycrystalline silicon layer 344 is formed on the upper surface of the sensor layer 308, and the formed polycrystalline silicon layer 344 is selectively removed by dry etching. The silicon oxide layer 342 is selectively removed by dry etching. As a result, the through electrode 332 of the mass portion 312 of the MEMS sensor 302 is formed, and the additional comb electrodes 324 b and 324 c disposed below the comb electrode portions 314 b and 314 c in the MEMS sensor 302 The relay wiring 326b disposed below is formed.

  Next, as shown in FIG. 28, a wafer 346 made of conductive single crystal silicon is prepared. The wafer 346 corresponds to the support layer 304.

  Next, as shown in FIG. 29, a silicon oxide layer 348 is formed on the upper surface of the support layer 304, and the formed silicon oxide layer 348 is selectively removed by dry etching. The silicon oxide layer 348 corresponds to the insulating layer 306, but the additional comb-tooth electrodes 324b and 324c of the mass portion 312 and the silicon oxide layer 348 at a position corresponding to the portion where the relay wiring 326b is not formed. , Used as a sacrificial layer, not removed at this stage, removed at the final stage of production.

  Next, as shown in FIG. 30, the sensor layer 308 of FIG. 27 is turned upside down and bonded to the upper surface of the substrate (that is, the upper surface of the insulating layer 306) formed of the support layer 304 and the insulating layer 306 of FIG. In this state, the upper surface of the sensor layer 308 is polished to adjust the thickness of the sensor layer 308. Thus, the through electrode 332 is exposed on the upper surface of the sensor layer 308.

  Next, as shown in FIG. 31, a silicon oxide layer 350 is formed on the upper surface of the sensor layer 308, and the formed silicon oxide layer 350 is selectively removed by dry etching. Furthermore, a conductive polycrystalline silicon layer 352 is formed on the upper surface of the sensor layer 308, and the formed polycrystalline silicon layer 352 is selectively removed by dry etching. As a result, in the MEMS sensor 302, the additional comb electrodes 324a and 324d disposed above the comb electrode portions 314a and 314d, the relay wiring 326a disposed above the mass portion 312, and the plate-like beam portions 316c and 316d. The relay wirings 328 a and 328 b disposed above the pad portion and the pad portions 330 a and 330 b disposed above the peripheral portion 318 are formed.

  Next, as shown in FIG. 32, the sensor layer 308 is etched away from the upper surface to the lower surface to pattern the sensor layer 308. Thus, the mass portion 312 of the sensor layer 308, the comb-tooth electrode portions 314a, 314b, 314c, and 314d, the plate-like beam portions 316a, 316b, 316c, and 316d, the peripheral portion 318, and the comb-tooth electrode portions 320a and 320b. , 320c, and 320d, and electrode support portions 322a, 322b, 322c, and 322d.

  Then, the MEMS sensor 302 can be obtained by etching away the insulating layer 306 under the mass part 312 which is a sacrificial layer.

(Example 5)
33 and 34 show a MEMS sensor 402 of this embodiment. The MEMS sensor 402 according to the present embodiment includes a support layer 404 made of conductive single crystal silicon, an insulating layer 406 made of silicon oxide, and a sensor layer 408 mainly made of conductive single crystal silicon. Are sequentially formed on the laminated substrate 410. In the following description, the lamination direction of the laminated substrate 410 (vertical direction in FIG. 33, vertical direction in FIG. 34) is taken as the Z direction, and the in-plane direction of the laminated substrate 410 is taken as the X direction and the Y direction. Further, in the following description, the positive direction in the Z direction (upward in FIG. 34) is referred to as the upper direction, and the negative direction in the Z direction (downward in FIG. 34) is referred to as the downward direction. In the MEMS sensor 402 of this embodiment, the insulating layer 406 is stacked above the support layer 404, and the sensor layer 408 is stacked above the insulating layer 406. The MEMS sensor 402 is used in combination with the arithmetic circuit 411.

  In the sensor layer 408, by selectively removing single crystal silicon by etching, the mass portion 412, the comb-tooth electrode portions 414a and 414b, the plate-like beam portions 416a, 416b, 416c and 416d, and the relay portion 418a. , 418b, straight beam portions 420a, 420b, 420c, 420d, relay support portions 422a, 422b, 422c, 422d, comb electrode portions 424a, 424b, comb electrode portions 426a, 426b, detection electrode support portion 428a and 428b, comb-tooth electrode portions 430a and 430b, and excitation electrode support portions 432a and 432b are formed. Among them, the mass 412, the comb-tooth electrodes 414a and 414b, the plate-like beams 416a, 416b, 416c and 416d, the relays 418a and 418b, the linear beams 420a, 420b, 420c and 420d, and the relay The support portions 422a, 422b, 422c, and 422d and the comb-tooth electrode portions 424a and 424b are integrally formed seamlessly, and these are maintained at the same potential. Further, the comb-tooth electrode portions 426a and 426b are integrally formed seamlessly with the corresponding detection electrode support portions 428a and 428b, and are maintained at the same potential. Further, the comb-tooth electrode portions 430a and 430b are integrally formed seamlessly with the corresponding excitation electrode support portions 432a and 432b, respectively, and are maintained at the same potential.

  The mass portion 412 is formed in a rectangular shape when the MEMS sensor 402 is viewed in plan from above. A comb electrode portion 414a is provided at one end (the end on the left side in FIG. 33) of the mass portion 412 in the X direction, and the other end (the right side in FIG. 33) of the mass portion 412 in the X direction. The comb-tooth electrode portion 414 b is provided at the end portion of the The comb-tooth electrode portions 414 a and 414 b are disposed at the center position of the mass portion 412 in the Y direction. The comb-tooth electrodes 414 a and 414 b each include a support extending from the mass 412 along the X direction, and an electrode extending from the support along the Y direction. The plate-like beams 416a and 416b are provided at one end (the upper end in FIG. 33) of the mass 412 in the Y direction, and the other end (Y in FIG. 33) of the mass 412 is provided. At the lower end), plate-like beams 416c and 416d are provided. The plate-like beams 416a and 416b extend from the mass 412 along the Y direction and are connected to the relay 418a. The plate-like beams 416c and 416d extend from the mass 412 along the Y direction and are connected to the relay 418b. The plate-like beam portions 416a, 416b, 416c, and 416d are formed in shapes that have high rigidity in the X and Y directions and low rigidity in the Z direction. The relay portions 418a and 418b are formed in a rectangular shape having a longitudinal direction in the X direction when the MEMS sensor 402 is viewed in plan from above. One end (the end on the left side in FIG. 33) of the relay portion 418a in the X direction is connected to the relay support portion 422a via the linear beam portion 420a. The other end (the end on the right side in FIG. 33) of the relay portion 418a in the X direction is connected to the relay support portion 422b via the linear beam portion 420b. A comb-tooth electrode portion 424 a extending along the Y direction is provided at an end of the relay portion 418 a in the Y direction. One end (the end on the left side in FIG. 33) of the relay portion 418b in the X direction is connected to the relay support portion 422c via the linear beam portion 420c. The other end (the end on the right side in FIG. 33) of the relay portion 418b in the X direction is connected to the relay support portion 422d via the linear beam portion 420d. A comb-tooth electrode portion 424 b extending along the Y direction is provided at an end of the relay portion 418 b in the Y direction. The straight beam portions 420a, 420b, 420c, and 420d are formed in shapes that have high rigidity in the X and Z directions and low rigidity in the Y direction. Mass part 412, comb-tooth electrode parts 414a and 414b, plate-like beam parts 416a, 416b, 416c and 416d, relay parts 418a and 418b, straight beam parts 420a, 420b, 420c and 420d, comb-tooth electrode part The lower insulating layer 406 is removed by etching and 424a and 424b are displaceable relative to the support layer 404. The relay support portions 422 a, 422 b, 422 c and 422 d are fixed to the support layer 404 via the lower insulating layer 406.

  The comb-tooth electrode portions 426a and 426b are arranged to mesh with the corresponding comb-tooth electrode portions 414a and 414b. Each of the comb-tooth electrode portions 426a and 426b includes an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The electrode portions of the comb-tooth electrode portions 426a and 426b are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 414a and 414b in the X direction. The support portions of the comb-tooth electrode portions 426a and 426b are connected to the corresponding detection electrode support portions 428a and 428b. In the comb-tooth electrode parts 426a and 426b, the lower insulating layer 406 is removed by etching, but the detection electrode support parts 428a and 428b are fixed to the support layer 404 via the lower insulating layer 406. . When the mass portion 412 is not displaced relative to the support layer 404, the position in the Z direction of the upper end of the comb electrode portions 414a and 414b is equal to the position in the Z direction of the upper end of the comb electrode portions 426a and 426b. The Z-direction position of the lower end of the comb-tooth electrode portions 414a and 414b coincides with the Z-direction position of the lower end of the comb-tooth electrode portions 426a and 426b.

  The comb-tooth electrode portions 430a and 430b are arranged to mesh with the corresponding comb-tooth electrode portions 424a and 424b. The comb-tooth electrode portions 430a and 430b respectively extend in the Y direction, and are arranged to face the corresponding comb-tooth electrode portions 424a and 424b in the X direction. The comb-tooth electrode portions 430a and 430b are connected to the corresponding excitation electrode support portions 432a and 432b, respectively. In the comb-tooth electrode portions 430a and 430b, the lower insulating layer 406 is removed by etching, but the excitation electrode support portions 432a and 432b are fixed to the support layer 404 via the lower insulating layer 406. . The position in the Z direction of the upper end of the comb electrode portions 424a and 424b coincides with the position in the Z direction of the upper end of the comb electrode portions 430a and 430b, and the position in the Z direction of the lower end of the comb electrode portions 424a and 424b Is the same as the Z-direction position of the lower end of the comb-tooth electrode portions 430a and 430b. The comb-tooth electrode portions 424a and 424b and the corresponding comb-tooth electrode portions 430a and 430b form a parallel plate capacitor. When a voltage is applied between the comb-tooth electrode portions 424a and 424b and the corresponding comb-tooth electrode portions 430a and 430b, the comb-tooth electrode portions 424a and 424b correspond to the corresponding comb-tooth electrode portions so as to increase their opposing areas. Electrostatic attraction acts to pull in 430 a and 430 b.

  As shown in FIG. 33, an additional comb electrode 434a is provided below the comb electrode portion 414a. In addition, an additional comb electrode 434 b is provided on the top of the comb electrode portion 414 b. The additional comb-tooth electrodes 434a and 434b may be made of any conductive material, for example, may be made of polycrystalline silicon to which conductivity is imparted, or aluminum Etc. may be comprised from metals, such as. The additional comb-teeth electrodes 434a and 434b are respectively connected to the corresponding comb-teeth electrodes 414a and 414b via the insulating films 436a and 436b, and are electrically insulated from the corresponding comb-teeth electrodes 414a and 414b. There is.

  As shown in FIG. 33, the additional comb electrode 434b is formed of the relay support portion 422d through the mass portion 412, the plate beam portion 416d, the relay portion 418b, and the relay wiring 438b provided on the upper surface of the straight beam portion 420d. It electrically conducts to the pad part 440b provided in the upper surface. The additional comb electrode 434a includes a through electrode 442 penetrating the mass portion 412 from the upper surface to the lower surface, and a relay wire 438a provided on the upper surface of the mass portion 412, the plate beam portion 416c, the relay portion 418b, and the linear beam portion 420c. The pad portion 440 a provided on the top surface of the relay support portion 422 c is electrically conducted via the same. Relay wires 438a and 438b, pad portions 440a and 440b, and through electrodes 442 may be made of any conductive material, and any material may be used, and conductive polycrystalline silicon is used. You may be comprised and you may be comprised from metals, such as aluminum. Relay wires 438a and 438b, pad portions 440a and 440b, and through electrodes 442 are mass portions 412, plate-like beams 416c and 416d, relay portions 418b, linear beams 420c and 420d, relay support portions 422c and 422d, and an insulating film. , And electrically insulate from the mass portion 412, the plate-like beam portions 416c and 416d, the relay portion 418b, the linear beam portions 420c and 420d, and the relay support portions 422c and 422d.

  The arithmetic circuit 411 is connected to the relay support portion 422b of the MEMS sensor 102, the detection electrode support portions 428a and 428b, the excitation electrode support portions 432a and 432b, and the pad portions 440a and 440b. The relay support portion 422b has the same potential as the comb-tooth electrode portions 414a and 414b and the comb-tooth electrode portions 424a and 424b. The detection electrode support portions 428a and 428b have the same potential as the comb electrode portions 426a and 426b, respectively, and the excitation electrode support portions 432a and 432b have the same potential as the comb electrode portions 430a and 430b, respectively 440a and 440b have the same potential as the additional comb-tooth electrodes 434a and 434b, respectively. The arithmetic circuit 411 can apply a voltage between each of the comb electrode portions 424a and 424b and the corresponding comb electrode portions 430a and 430b, and corresponds to each of the additional comb electrodes 434a and 434b. Capacitance between the comb-tooth electrode portions 426a and 426b can be detected.

  The operation of the MEMS sensor 402 will be described below. When a voltage is applied between the comb-tooth electrode portion 424a and the comb-tooth electrode portion 430a, an electrostatic attractive force is exerted to pull the comb-tooth electrode portion 424a to the comb-tooth electrode portion 430a, and the relay portion 418a and the plate-like beam The portions 416a and 416b, the mass portion 412, the plate-like beams 416c and 416d, and the relay portion 418b are integrally displaced upward in FIG. Conversely, when a voltage is applied between the comb-tooth electrode portion 424b and the comb-tooth electrode portion 430b, an electrostatic attractive force is exerted to pull the comb-tooth electrode portion 424b to the comb-tooth electrode portion 430b, and the relay portion 418b The plate-like beams 416c and 416d, the mass 412, the plate-like beams 416a and 416b, and the relay 418a are integrally displaced downward in FIG. By alternately applying such a voltage, the mass portion 412 is excited in the Y direction.

  When an angular velocity around the X axis acts on the MEMS sensor 402 in a state where the mass portion 412 vibrates in the Y direction, Coriolis force in the Z direction acts on the mass portion 412 and the mass portion 412 vibrates in the Z direction Do. The amplitude of the Z-direction vibration of the mass portion 412 at this time is proportional to the magnitude of the angular velocity around the X axis acting on the MEMS sensor 402. When the mass portion 412 vibrates in the Z direction, the comb-tooth electrode portions 414 a and 414 b and the additional comb-tooth electrodes 434 a and 434 b vibrate in the Z direction (vertical direction in FIG. 34) with respect to the comb-tooth electrode portions 426 a and 426 b. The arithmetic circuit 411 detects the capacitance between the additional comb electrodes 434 a and 434 b and the corresponding comb electrodes 426 a and 426 b, and calculates the difference between the two, thereby acting on the MEMS sensor 402. An angular velocity around an axis can be detected.

  Similar to the MEMS sensor 302 of the fourth embodiment, according to the MEMS sensor 402 of the present embodiment, the capacitance between the comb electrode portion 414 b and the comb electrode portion 426 b provided with the additional comb electrode 434 b above The Z value of the mass portion 412 is calculated by the calculation circuit 411 by calculating the difference between the capacitances of the comb electrode portion 414a and the comb electrode portion 426a provided with the additional comb electrode 434a below. Only changes in capacitance due to directional displacement can be detected. In addition, according to the MEMS sensor 402 of this embodiment, it is detected from the sign of the difference calculated by the arithmetic circuit 411 whether the mass portion 412 is displaced in the positive direction of the Z direction or in the negative direction. be able to. By this, the displacement amount of the mass portion 412 in the Z direction can be accurately detected, and the angular velocity around the X axis acting on the mass portion 412 can be accurately detected.

(Example 6)
35 to 37 show the MEMS sensor 502 of this embodiment. In the MEMS sensor 502, a support layer 504 made of conductive single crystal silicon, an insulating layer 506 made of silicon oxide, and a sensor layer 508 mainly made of conductive single crystal silicon are sequentially stacked. Also, it is formed on the laminated substrate 510. In the following description, the stacking direction of the layered substrate 510 (vertical direction in FIG. 35, vertical direction in FIGS. 36 and 37) is taken as the Z direction, and the in-plane direction of the layered substrate 510 is taken as the X direction and the Y direction. Further, in the following description, the positive direction in the Z direction (upper direction in FIGS. 36 and 37) is referred to as the upper direction, and the negative direction in the Z direction (lower direction in FIGS. 36 and 37) is referred to as the lower direction. In the MEMS sensor 502 of this embodiment, the insulating layer 506 is stacked above the support layer 504, and the sensor layer 508 is stacked above the insulating layer 506. The MEMS sensor 502 is used in combination with the arithmetic circuit 511.

  In the sensor layer 508, by selectively removing single crystal silicon by etching, the mass portion 512, the comb-tooth electrode portions 514a, 514b, 514c, 514d, and the plate-like beam portions 516a, 516b, 516c, 516d and The peripheral portion 518, the comb-tooth electrode portions 520a, 520b, 520c, and 520d, and the electrode support portions 522a, 522b, 522c, and 522d are formed. Among them, the mass portion 512, the comb-tooth electrode portions 514a, 514b, 514c, 514d, the plate-like beam portions 516a, 516b, 516c, 516d, and the peripheral portion 518 are integrally formed seamlessly. Is maintained at the same potential. Further, the comb-tooth electrode portions 520a, 520b, 520c, and 520d are integrally formed seamlessly with the corresponding electrode support portions 522a, 522b, 522c, and 522d, respectively, and are maintained at the same potential.

  The mass portion 512 is formed in a rectangular shape when the MEMS sensor 502 is viewed in plan from above. Although not shown, the mass portion 512 is formed with a plurality of etching holes penetrating the mass portion 512 from the upper surface to the lower surface. The comb-like electrode portions 514a and 514b are provided at one end of the mass portion 512 in the X direction (the end on the right side in FIG. 35), and the other end of the mass portion 512 in the X direction (FIG. 35) The comb-shaped electrode portions 514c and 514d are provided at the left end of the The comb-tooth electrode portion 514 a and the comb-tooth electrode portion 514 b are disposed at symmetrical positions with respect to the center position of the mass portion 512 in the Y direction. Similarly, the comb-tooth electrode portion 514 c and the comb-tooth electrode portion 514 d are disposed at symmetrical positions with respect to the center position of the mass portion 512 in the Y direction. The comb-tooth electrodes 520a, 520b, 520c, and 520d each include a support extending from the mass 512 along the X direction, and an electrode extending from the support along the Y direction. Plate-like beam portions 516a and 516b are provided at one end (the upper end in FIG. 35) of the mass 512 in the Y direction, and the other end of the mass 512 in the Y direction (FIG. 35) The plate-like beam portions 516c and 516d are provided at the lower end portion thereof. The plate-like beams 516 a, 516 b, 516 c, 516 d extend from the mass 512 along the Y direction and are connected to the peripheral edge 518. The plate-like beams 516a, 516b, 516c, and 516d are formed in shapes that have high rigidity in the X direction and Y direction and low rigidity in the Z direction. The peripheral portion 518 has the mass portion 512, the comb-tooth electrode portions 514a, 514b, 514c, and 514d, the plate-like beam portions 516a, 516b, 516c, and 516d, and the comb-tooth portions when the MEMS sensor 502 is viewed from above. It is formed in a rectangular frame shape surrounding the electrode parts 520a, 520b, 520c, 520d and the electrode support parts 522a, 522b, 522c, 522d. The lower insulating layer 506 of the mass 512, the comb-tooth electrodes 514a, 514b, 514c, 514d, and the plate-like beams 516a, 516b, 516c, 516d is removed by etching. Relatively displaceable. The peripheral portion 518 is fixed to the support layer 504 via the lower insulating layer 506.

  The comb-tooth electrode portions 520a, 520b, 520c, and 520d are arranged to mesh with the corresponding comb-tooth electrode portions 514a, 514b, 514c, and 514d, respectively. The comb-tooth electrode portions 520a, 520b, 520c, and 520d each include an electrode portion extending in the Y direction and a support portion extending in the X direction and supporting the electrode portion. The electrode portions of the comb-tooth electrode portions 520a, 520b, 520c, and 520d are arranged to face the electrode portions of the corresponding comb-tooth electrode portions 514a, 514b, 514c, and 514d in the X direction. The support portions of the comb-tooth electrode portions 520a, 520b, 520c, and 520d are connected to the corresponding electrode support portions 522a, 522b, 522c, and 522d. In the comb-tooth electrode portions 520a, 520b, 520c, and 520d, the lower insulating layer 506 is removed by etching, but in the electrode support portions 522a, 522b, 522c, and 522d, the support layer 504 is interposed between the lower insulating layers 506. It is fixed against. In the state where the mass portion 512 is not displaced relative to the support layer 504, the position in the Z direction of the upper end of the comb electrode portions 514a, 514b, 514c, and 514d is the position of the comb electrode portions 520a, 520b, 520c, and 520d. The position in the Z direction of the lower end of the comb electrode portions 514a, 514b, 514c, 514d is the same as the position in the Z direction of the upper end, the position in the Z direction of the lower end of the comb electrode portions 520a, 520b, 520c, 520d It matches with. The comb-tooth electrode portions 514a, 514b, 514c, 514d and the comb-tooth electrode portions 520a, 520b, 520c, 520d form a parallel plate capacitor. When the comb-tooth electrode portions 514a, 514b, 514c, and 514d are displaced relative to the comb-tooth electrode portions 520a, 520b, 520c, and 520d in the Z direction, and the opposing area of the both changes, electrostatics formed between the two The size of the capacity also changes. The change in capacitance can be detected by the arithmetic circuit 511.

  As shown in FIGS. 36 and 37, additional comb electrodes 524a and 524d are provided above the comb electrode portions 514a and 514d. Further, additional comb electrodes 524 b and 524 c are provided below the comb electrode portions 514 b and 514 c. In the MEMS sensor 502 according to the present embodiment, the additional comb electrodes 524a, 524b, 524c, and 524d may be made of any conductive material, for example, the conductive members are given conductivity. It may be composed of polycrystalline silicon or may be composed of a metal such as aluminum. The additional comb-tooth electrodes 524a, 524b, 524c, and 524d are electrically conducted to the corresponding comb-tooth electrode portions 514a, 514b, 514c, and 514d, respectively.

  As shown in FIGS. 36 and 37, additional comb electrodes 526a and 526d are provided below the comb electrodes 520a and 520d. Further, additional comb electrodes 526 b and 526 c are provided above the comb electrode portions 520 b and 520 c. In the MEMS sensor 502 according to this embodiment, the additional comb-teeth electrodes 526a, 526b, 526c, and 526d may be made of any conductive material, for example, to which conductivity is added. It may be composed of polycrystalline silicon or may be composed of a metal such as aluminum. The additional comb-tooth electrodes 526a, 526b, 526c, 526d are electrically conducted to the corresponding comb-tooth electrodes 520a, 520b, 520c, 520d, respectively.

  The arithmetic circuit 511 is connected to the peripheral portion 518 of the MEMS sensor 502 and the electrode support portions 522a, 522b, 522c, and 522d. The peripheral portion 518 has the same potential as the comb-tooth electrode portions 514a, 514b, 514c, and 514d. In addition, the electrode support portions 522a, 522b, 522c, and 522d have the same potential as the comb-tooth electrode portions 520a, 520b, 520c, and 520d, respectively. The arithmetic circuit 511 can detect the capacitance between each of the comb-tooth electrode portions 514a, 514b, 514c, and 514d and the corresponding comb-tooth electrode portions 520a, 520b, 520c, and 520d.

  The operation of the MEMS sensor 502 will be described below. When an acceleration in the Z direction acts on the mass portion 512, an inertial force in the Z direction acts on the mass portion 512, and the plate beams 516a, 516b, 516c, and 516d are bent and deformed in the Z direction. As a result, the mass portion 512 and the comb-tooth electrode portions 514 a, 514 b, 514 c, and 514 d are displaced relative to the support layer 504 in the Z direction. The amount of displacement in the Z direction at this time is proportional to the magnitude of the acceleration acting on the mass portion 512. On the other hand, the positions of the comb electrode portions 520 a, 520 b, 520 c, and 520 d are fixed with respect to the support layer 504. Therefore, when acceleration in the Z direction acts on the MEMS sensor 502, the comb-tooth electrode portions 514a, 514b, 514c, and 514d are displaced relative to the comb-tooth electrode portions 520a, 520b, 520c, and 520d in the Z direction. The relative displacement amount in the Z direction at this time has a magnitude corresponding to the acceleration in the Z direction. In the present specification, the comb-tooth electrode portions 514 a, 514 b, 514 c, and 514 d relatively displaced with respect to the support layer 504 are also referred to as movable comb-tooth electrodes. Further, the comb-tooth electrode portions 520a, 520b, 520c, and 520d which are not displaced relative to the support layer 504 are also referred to as fixed comb-tooth electrodes.

  In (a) of FIG. 38, the comb-tooth electrode portions 514a and 514c, the additional comb-tooth electrodes 524a and 524c, and the comb-tooth electrode portion 520a in a state where the mass portion 512 is not displaced relative to the support layer 504. , 520c and the additional comb electrodes 526a, 526c. In this state, the comb-tooth electrode portion 514a and the comb-tooth electrode portion 520a completely overlap each other, and the opposing area between them is equal to the area of the comb-tooth electrode portion 514a and the comb-tooth electrode portion 520a. Further, in this state, the comb-tooth electrode portion 514c and the comb-tooth electrode portion 520c completely overlap each other, and the opposing area of both is equal to the area of the comb-tooth electrode portion 514c and the comb-tooth electrode portion 520c. In this state, when the arithmetic circuit 511 subtracts the capacitance between the comb electrode portion 514a and the comb electrode portion 520a from the capacitance of the comb electrode portion 514c and the comb electrode portion 520c, the difference is It will be zero.

  As shown in (b) of FIG. 38, when the mass portion 512 is displaced relative to the support layer 504 downward (in the negative direction of the Z direction), the comb-tooth electrode portions 514a, 514c become comb-tooth electrode portions 520a, 520c. Relative to the lower part. In this case, with respect to the comb electrode portion 520a, when the comb electrode portion 514a is relatively displaced downward, the additional comb electrode 526a provided below the comb electrode portion 520a faces the comb electrode portion 514a, Since the additional comb electrode 524a provided above the comb electrode portion 514a is opposed to the comb electrode portion 520a, the opposing area is increased, and the capacitance between the comb electrode portion 514a and the comb electrode portion 520a is increased. Will increase. Unlike this, with respect to the comb electrode portion 520c, when the comb electrode portion 514c is relatively displaced downward, the opposing area is reduced, and the capacitance between the comb electrode portion 514c and the comb electrode portion 520c is decreased. Do. In this state, when the arithmetic circuit 511 subtracts the capacitance between the comb electrode portion 514a and the comb electrode portion 520a from the capacitance of the comb electrode portion 514c and the comb electrode portion 520c, the difference is The magnitude is the absolute value of the increase in capacitance between the comb electrode portion 514a and the comb electrode portion 520a, and the decrease amount of capacitance between the comb electrode portion 514c and the comb electrode portion 520c. It is equal to the sum of absolute values, and the sign of the difference is negative.

  As shown in (c) of FIG. 38, when the mass portion 512 is relatively displaced upward (in the positive direction of the Z direction) with respect to the support layer 504, the comb-tooth electrode portions 514a, 514c become comb-tooth electrode portions 520a, 520c. Relative displacement upward with respect to In this case, with regard to the comb electrode portion 520c, when the comb electrode portion 514c is relatively displaced upward, the additional comb electrode 526c provided above the comb electrode portion 520c faces the comb electrode portion 514c, Since the additional comb electrode 524c provided below the comb electrode portion 514c faces the comb electrode portion 520c, the opposing area is increased, and the capacitance between the comb electrode portion 514c and the comb electrode portion 520c is increased. Will increase. Unlike this, with respect to the comb electrode portion 520a, when the comb electrode portion 514a is relatively displaced upward, the opposing area decreases, and the capacitance between the comb electrode portion 514a and the comb electrode portion 520a decreases. Do. In this state, when the arithmetic circuit 511 subtracts the capacitance between the comb electrode portion 514a and the comb electrode portion 520a from the capacitance of the comb electrode portion 514c and the comb electrode portion 520c, the difference is The magnitude is the absolute value of the decrease in capacitance between the comb electrode portion 514a and the comb electrode portion 520a, and the increase in capacitance between the comb electrode portion 514c and the comb electrode portion 520c. It is equal to the value obtained by adding the absolute value, and the sign of the difference is positive.

  According to the MEMS sensor 502 of this embodiment, the capacitance between the comb-tooth electrode portion 514a provided with the additional comb-tooth electrode 524a and the comb-tooth electrode portion 520a provided with the additional comb-tooth electrode 526a below The arithmetic circuit 511 calculates the difference between the electrostatic capacitances between the comb electrode portion 514c provided with the additional comb electrode 524c below and the comb electrode portion 520c provided with the additional comb electrode 526c above. By calculating in the above, it is possible to detect only the change in capacitance resulting from the displacement of the mass portion 512 in the Z direction. In addition, according to the MEMS sensor 502 of this embodiment, it is determined from the sign of the difference calculated by the arithmetic circuit 511 whether the mass unit 512 is displaced in the positive direction of the Z direction or in the negative direction. be able to. By this, the displacement amount of the mass portion 512 in the Z direction can be accurately detected, and the acceleration in the Z direction acting on the mass portion 512 can be accurately detected.

  The MEMS sensor 502 of the present embodiment can be manufactured by the same manufacturing method as that of the MEMS sensor 2 of the first embodiment, and thus the detailed description of the manufacturing method is omitted.

  As mentioned above, although the specific example of this invention was described in detail, these are only an illustration and do not limit a claim. The art set forth in the claims includes various variations and modifications of the specific examples illustrated above.

  The technical elements described in the present specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques exemplified in the present specification or the drawings can simultaneously achieve a plurality of purposes, and achieving one of the purposes itself has technical utility.

2: MEMS sensor; 4: support layer; 6: insulating layer; 8: sensor layer; 10: laminated substrate; 11: arithmetic circuit; 12: mass portion; 14a: comb electrode portion; 14b: comb electrode portion; 16d: plate beam portion 16b: plate beam portion 16c: plate beam portion 16d: plate beam portion 18: peripheral portion 20a: comb teeth 20b: comb electrode portion; 20 d: comb electrode portion; 22a: electrode support portion; 22b: electrode support portion; 22c: electrode support portion; 22d: electrode support portion; 24a: Additional comb electrode 24b: additional comb electrode 24c: additional comb electrode 24d: additional comb electrode 30: wafer 32: silicon oxide layer 34: polycrystalline silicon layer 36: wafer 38: oxide Silicon layer; 40: Silicon oxide layer; 42: Polycrystalline silicon layer; 102 MEMS sensor; 104: support layer; 106: insulating layer; 108: sensor layer; 110: laminated substrate; 111: arithmetic circuit; 112: mass portion; 114a: comb electrode portion; 114b: comb electrode portion; 116a: plate 116b: plate beam portion 116c: plate beam portion 116d: plate beam portion 118a: relay portion 118b: relay portion 120a: straight beam portion 120b: straight beam portion 120c: straight beam portion Beam portion 120d: straight beam portion 122a: relay support portion 122b: relay support portion 122c: relay support portion 122d: relay support portion 124a: comb electrode portion 124b: comb electrode portion 126a: comb Tooth electrode part; 126b: comb electrode part; 128a: detection electrode support part; 128b: detection electrode support part; 130a: comb electrode part; 130b: comb electrode part; 132a: excitation electrode support part; Excitation electrode support part: 134a: additional comb electrode; 134 b: additional comb electrode; 202: MEMS sensor; 204: support layer; 206: insulating layer; 208: sensor layer; 210: laminated substrate; 211: arithmetic circuit; : Mass part; 214a: comb electrode part; 214b: comb electrode part; 214c: comb electrode part; 214d: comb electrode part; 216a: plate beam part; 216b: plate beam part; Beam part 216d: plate beam part 218: peripheral part 220a: comb electrode part 220b: comb electrode part 220c: comb electrode part 220 d: comb electrode part 222a: electrode support part 222 b : Electrode support portion; 222c: electrode support portion; 222d: electrode support portion; 224a: additional comb electrode; 224b: additional comb electrode; 224c: additional comb electrode; 224d: additional comb electrode; 226a: relay wiring; 226b: relay wiring; 228a: relay wiring; 228b: relay wiring; 230a: pad unit; 230b: pad unit; 232: through electrode; 302: MEMS sensor; 304: support layer; 306: insulating layer; 308: sensor layer; 310: laminated substrate; 311: arithmetic circuit; 312: mass part; 314a: comb electrode part; 314b: comb electrode part; 314c: comb electrode part; 314 d: comb electrode part; 316a: plate beam part; 316b: plate beam portion; 316c: plate beam portion; 316 d: plate beam portion; 318: peripheral edge portion; 320a: comb electrode portion; 320b: comb electrode portion; 320c: comb electrode portion; Tooth electrode portion; 322a: electrode support portion; 322b: electrode support portion; 322c: electrode support portion; 322d: electrode support portion; 324a: additional comb electrode; 324b: additional comb electrode; Tooth electrode; 324d: additional comb-teeth electrode; 326a: relay wiring; 326b: relay wiring; 328a: relay wiring; 328b: relay wiring; 330a: pad portion; 330b: pad portion; 332: through electrode; 334a: insulating film; 334b: insulating film; 334c: insulating film; 336: insulating film; 340: wafer; 342: silicon oxide layer; 344: polycrystalline silicon layer; 346: wafer; 348: silicon oxide layer; Silicon layer; 352: polycrystalline silicon layer; 402: MEMS sensor; 404: support layer; 406: insulating layer; 408: sensor layer; 410: laminated substrate; 411: arithmetic circuit; 412: mass part; Part: 414b: comb-like electrode part; 416a: plate-like beam part; 416b: plate-like beam part; 416c: plate-like beam part; 416 d: plate-like beam part 18a: relay portion; 418b: relay portion; 420a: straight beam portion; 420b: straight beam portion; 420d: straight beam portion; 422a: relay support portion; 422b: relay support portion; 422c: relay support Part: 422d: Relay support part; 424a: comb electrode part; 424 b: comb electrode part; 426a: comb electrode part; 426b: comb electrode part; 428a: detection electrode support part; 428b: detection electrode support part; 430a: comb electrode portion; 430b: comb electrode portion; 432a: excitation electrode support portion; 432b: excitation electrode support portion; 434a: additional comb electrode; 434b: additional comb electrode; 436a: insulating film; 438a: relay wiring; 438b: relay wiring; 440a: pad portion; 440b: pad portion; 442: through electrode; 502: MEMS sensor; 504: support layer; : Insulating layer; 508: sensor layer; 510: laminated substrate; 511: arithmetic circuit; 512: mass portion; 514a: comb electrode portion; 514b: comb electrode portion; 514c: comb electrode portion; 516a: plate beam portion 516b: plate beam portion 516c: plate beam portion 516d: plate beam portion 518: peripheral edge portion 520a: comb electrode portion 520b: comb electrode portion 520c : Comb-tooth electrode portion; 520 d: comb-tooth electrode portion; 522a: electrode support portion; 522b: electrode support portion; 522c: electrode support portion; 522d: electrode support portion; 524a: additional comb-tooth electrode; 524b: additional comb-tooth electrode 524c: additional comb electrode; 524 d: additional comb electrode; 526a: additional comb electrode; 526 b: additional comb electrode; 526 c: additional comb electrode; 526 d: additional comb electrode

Claims (6)

A first fixed comb electrode,
The first fixed comb electrode is disposed so as to be engaged, the position of the upper end is approximately equal to the position of the upper end of the first fixed comb electrode, and the position of the lower end is approximately equal to the position of the lower end of the first fixed comb electrode , A first movable comb electrode,
A second fixed comb electrode,
The second fixed comb electrode is disposed in mesh with the second fixed comb electrode, and the position of the upper end is approximately equal to the position of the upper end of the second fixed comb electrode, and the position of the lower end is approximately equal to the position of the lower end of the second fixed comb electrode , And a second movable comb electrode,
A first additional comb electrode made of a conductive material is provided above the first movable comb electrode,
A MEMS sensor, wherein a second additional comb electrode made of a conductive material is provided below the second movable comb electrode. The first movable comb electrode and the first additional comb electrode are electrically conducted,
The MEMS sensor according to claim 1, wherein the second movable comb electrode and the second additional comb electrode are electrically connected. The first movable comb electrode and the first additional comb electrode are electrically insulated;
The MEMS sensor according to claim 1, wherein the second movable comb electrode and the second additional comb electrode are electrically insulated. The first movable comb electrode and the first additional comb electrode are connected via an insulating film,
The MEMS sensor according to claim 3, wherein the second movable comb electrode and the second additional comb electrode are connected via an insulating film. The first movable comb electrode and the first additional comb electrode are connected via a PN junction,
The MEMS sensor according to claim 3, wherein the second movable comb electrode and the second additional comb electrode are connected via a PN junction. Under the first fixed comb electrode, a third additional comb electrode made of a conductive material is provided,
The MEMS sensor according to claim 1, wherein a fourth additional comb electrode made of a conductive material is provided above the second fixed comb electrode.

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