JP2010071964A - Physical quantity sensor and manufacturing method therefor - Google Patents

Abstract

A capacitance type physical quantity sensor according to the present invention provides a physical quantity sensor that can be downsized or improve the sensitivity of the sensor without deteriorating sensor characteristics, and a method for manufacturing the same.
A physical quantity sensor includes a semiconductor substrate including a frame portion, a weight portion disposed inside the frame portion, a flexible portion connecting the weight portion and the frame portion, and one of the frame portions. A first support substrate bonded to the side, a second support substrate bonded to the other side of the frame portion, and at least one of the first support substrate and the second support substrate. A wiring terminal that conducts between one side and the other side of the support substrate; a first electrode that is provided on a surface of the first support substrate; a first electrode that faces the weight; and a surface of the second support substrate; A second electrode facing the weight portion, and the frame portion is provided with a through wiring portion that conducts between one side and the other side of the frame portion, and the through wiring portion and the wiring terminal are electrically connected to each other. Connected.
[Selection] Figure 1

Description

  The present invention relates to a physical quantity sensor that detects a physical quantity using a capacitive element and a manufacturing method thereof, and more particularly, to a sensor that detects acceleration in a plurality of directions and / or angular velocity.

  In recent years, a type of sensor using a capacitive element (so-called capacitance type sensor) has been put to practical use as an acceleration sensor or an angular velocity sensor having a small and simple structure by using MEMS (Micro Electro Mechanical Systems) technology. Yes. In general, a capacitance type sensor has a weight part that can be displaced with a predetermined degree of freedom in a semiconductor substrate sandwiched between a pair of glass substrates, and the weight part can be displaced with acceleration or angular velocity. It is used as a weight part to detect. The displacement is detected based on the capacitance value of the capacitive element. Conventionally, in order to detect a physical quantity of a multi-axis component in a capacitance type sensor, a combination of a plurality of single-axis sensors has been used, but this is a problem in terms of size and cost.

  Therefore, research on a capacitive sensor capable of detecting multi-axis components with a single sensor element is in progress. In such a sensor that detects a physical quantity of a multi-axis component using one sensor element, an electrode constituting the capacitive element is used to detect the physical quantity of the multi-axis component or drive the weight portion using the capacitive element. For this, wiring connection to the outside is required. In order to perform this wiring connection simply and efficiently, for example, a pair of upper and lower glass substrates are connected in a semiconductor substrate, and a wiring columnar body made of a conductive material is disposed around the weight portion. A sensor that takes electrical connection with an electrode and a metal wiring by a body is disclosed (Patent Document 1 and Non-Patent Document 1).

However, securing the formation region of the columnar body for wiring in the sensor has caused problems such as preventing the sensor from being downsized or limiting the size of the weight portion. Therefore, a sensor is disclosed in which a columnar body (post structure) is arranged on a weight part or a beam connecting the weight part and the frame (Patent Document 2).
JP 2007-3192 A JP 2007-192621 A Transactions on Sensors and Micromachines, Vol. 126, no. 6,2006 (Journal of the Institute of Electrical Engineers of Japan, Vol. 126, No. 6, 2006)

  According to the sensor of Patent Document 2, it is difficult to form a columnar body on a weight part or a beam due to non-uniformity of processing in the wafer surface where the sensor is arranged. Reduce. Further, providing a columnar body with respect to a beam (a fragile flexible part) causes a reduction in the strength of the beam. Further, by providing a columnar body in the weight portion, the weight portion is reduced in mass, and the sensor characteristics are deteriorated.

  SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to provide a physical quantity sensor that can reduce the size or improve the sensitivity of a sensor in a capacitance type physical quantity sensor without deteriorating sensor characteristics, and a method for manufacturing the same. To do.

  The physical quantity sensor according to the present invention includes a semiconductor substrate including a frame portion, a weight portion disposed inside the frame portion, a flexible portion connecting the weight portion and the frame portion, and the frame A first support substrate bonded to one side of the portion, a second support substrate bonded to the other side of the frame portion, and provided on at least one of the first support substrate and the second support substrate, A wiring terminal for conducting one side and the other side of the first support substrate or the second support substrate; a first electrode provided on the first support substrate and opposed to the weight portion; 2 is provided on the support substrate, and is provided with a second electrode facing the weight portion, and the frame portion is provided with a through wiring portion that conducts between the frame portion and one side and the other side, The through wiring part and the wiring terminal are electrically connected. And butterflies.

  In the method of manufacturing a physical quantity sensor according to the present invention, a frame portion, a weight portion disposed inside the frame portion, and a flexible portion that connects the weight portion and the frame portion are formed on a semiconductor substrate. And forming a through-hole penetrating the frame portion and one side and the other side in a partial region of the frame portion, an insulating layer in the through-hole and an opening peripheral region of the through-hole, and the insulating Forming a conductive layer disposed on the layer, forming a through-wiring portion that conducts between the frame portion and one side and the other side, and on the first support substrate joined to one side of the frame portion Forming a first electrode and a wiring electrically connected to the first electrode, and a second electrode and the second electrode on a second support substrate joined to the other side of the frame portion. A wiring electrically connected to the first electrode and the weight portion and the first electrode facing each other. Joining the first support substrate and one side of the frame portion, and joining the second support substrate and the other side of the frame portion to face the weight portion and the second electrode, A wiring terminal provided on at least one of the first support substrate and the second support substrate and electrically connecting one side and the other side of the first support substrate or the second support substrate; The through wiring portion and the wiring terminal portion are electrically connected through the wiring formed on the supporting substrate and the second supporting substrate.

  According to the present invention, in a capacitance-type physical quantity sensor, by providing a through-wiring portion in a frame portion, the sensitivity of the sensor is improved by downsizing or enlarging a weight portion compared to a conventional sensor. It is possible to provide a physical quantity sensor and a method for manufacturing the same.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
<Structure of physical quantity sensor>
FIG. 1 is an exploded perspective view showing a state in which the physical quantity sensor 100 is disassembled. In FIG. 1, two axes (X axis and Y axis) perpendicular to the plane of the physical quantity sensor 100 are set, and a direction perpendicular to the two axes is defined as a Z axis. The physical quantity sensor 100 is configured by sandwiching a semiconductor substrate W between a first support substrate 140 and a second support substrate 150 positioned above and below the semiconductor substrate W. The semiconductor substrate W is configured by laminating a silicon film 110, a BOX layer 120, and a silicon substrate 130 in this order. The semiconductor substrate W is manufactured by a manufacturing process as will be described later, and a frame-like frame (including the frame part 111 and the frame part 131) having an opening penetrating the inside of the semiconductor substrate W, and the frame is flexible in the frame. The weight portion (including the weight joint portion 112 and the weight portion 132) that is displaceably supported by the flexible portion 113 (113a to 113d) having a property is integrally configured, and a sensor portion that detects a physical quantity is provided. Forming. Further, the frame has through-wiring portions P (P1 to P10) that pass through the upper and lower sides of the semiconductor substrate W to ensure conduction (not shown here for the sake of easy viewing).

  The outer periphery of the silicon film 110, the BOX layer 120, the silicon substrate 130, the first support substrate 140, and the second support substrate 150 has a substantially square shape of 3 mm × 3 mm, for example, and their heights are 20 μm, 2 μm, and 600 μm, respectively. , 500 μm and 500 μm. These external shapes and heights are examples, and are not limited to the above. In addition, the external size of the conventional physical quantity sensor is about 3 mm × 3 mm, and the case where the external size of the physical quantity sensor 100 of the present embodiment is also 3 mm × 3 mm is illustrated. Further, in the physical quantity sensor 100 of the present embodiment, a through wiring portion P that conducts an upper surface and a lower surface of a semiconductor substrate W described later is provided. With this configuration, the physical quantity sensor 100 according to the present embodiment can reduce the outer size to 1.5 mm × 1.5 mm without changing the size of the weight used in the conventional physical quantity sensor. It is possible to reduce the size to about 1/4 compared to the overall external size. Further, if the overall size of the physical quantity sensor 100 of the present embodiment is a substantially square shape of 3 mm × 3 mm, the size of the weight part 132 described later is about the size of the weight part used in the conventional physical quantity sensor. The sensitivity as a physical quantity sensor can be improved.

  The semiconductor substrate W including the silicon film 110, the BOX layer 120, and the silicon substrate 130 can be manufactured using an SOI (Silicon On Insulator) substrate. Moreover, the 1st support substrate 140 and the 2nd support substrate 150 are comprised by either a glass material, a semiconductor material, a metal material, and an insulating resin material.

  2A to 2C are plan views showing the upper surfaces of (A) the silicon film 110, (B) the BOX layer 120, and (C) the silicon substrate 130, respectively. 3A to 3C are respectively (A) the lower surface of the first support substrate 140, (B) the upper surface of the second support substrate 150 (wiring terminals are not shown), and (C) the second support. 3 is a plan view showing a lower surface of a substrate 150. FIG.

  In the silicon film 110 shown in FIG. 2A, a frame portion 111, weight joint portions 112 (112a to 112e), and a flexible portion 113 are formed. The frame part 111 is a frame-shaped substrate whose outer periphery and inner periphery are both substantially square. The weight joint portion 112 (112a to 112e) has a substantially clover-like shape when FIG. 2A is viewed from the vertical direction. The weight joint portion 112 is joined to the weight portion 132 (weight portions 132a to 132e shown in FIG. 2C) having substantially the same shape as the weight joint portion 112 via the BOX layer 120b, and is integrated with the frame portion 111. Is displaced. 2 (A) and 2 (C), the alphabetic portions (a to e) of the reference numerals attached to the weight joint portions 112a to 112e and the weight portions 132a to 132e are the same in correspondence with the mutual positional relationship. It is attached in order. The flexible portions 113a to 113d are substantially rectangular substrates, respectively, and connect the frame portion 111 and the weight joint portions 112a to 112e in four directions. The flexible portions 113a to 113d have flexibility because they are thin, and function as beams that can be bent. When the flexible portions 113a to 113d are bent, the weight joint portions 112a to 112e can be displaced with respect to the frame portion 111.

  The upper surface of the weight junction 112a functions as a drive electrode E (see FIG. 5) described later. The driving electrode E on the upper surface of the weight junction 112a is capacitively coupled to a driving electrode 144a (see FIG. 5), which will be described later, installed on the lower surface of the first support substrate 140, and these driving electrodes E-144a. The weight junctions 112a to 112e are vibrated in the Z-axis direction by the voltage applied therebetween. Details of this drive will be described later.

  The upper surfaces of the weight joint portions 112b to 112e function as detection electrodes E (see FIG. 5) described later that detect displacement of the weight joint portion 112 in the X-axis and Y-axis directions, respectively. The detection electrodes E on the upper surfaces of the weight joint portions 112b to 112e are capacitively coupled to detection electrodes 144b to 144e (described later) installed on the lower surface of the first support substrate 140, respectively. In addition, the alphabet part (b-e) of the code | symbol attached | subjected to the weight junction parts 112b-112e and the electrodes 144b-144e for detection, respectively, is attached | subjected in the same order corresponding to the mutual positional relationship. Details of this detection will be described later.

  In the silicon substrate 130, a frame part 131 and a weight part 132 (132a to 132e) are formed. In the silicon substrate 130, the frame portion 131 and the weight portion 132 (132a to 132e) can be formed by forming an opening by etching the semiconductor substrate W. The height of the weight portion 132 (in the Z-axis direction in FIG. 2) is created to be lower than the height of the frame portion 131. This is because a gap corresponding to the measurement range is secured between the weight part 132 and the second support substrate 150 and the weight part 132 can be displaced.

  The frame portion 131 is a frame-shaped substrate having both an outer periphery and an inner periphery that are substantially square, and has a shape corresponding to the frame portion 111 of the silicon film 110. The frame part 131 is joined to the frame part 111 via the BOX layer 120 a and is integrated with the frame part 111.

  The weight part 132 functions as a weight (action body) that receives a force caused by acceleration or a Coriolis force caused by angular velocity. The weight part 132 is divided into substantially rectangular parallelepiped weight parts 132a to 132e. Weight parts 132b to 132e are connected to the weight part 132a arranged at the center from four directions, and can be displaced (moved or rotated) integrally as a whole. That is, the weight part 132a functions as a connection part for connecting the weight parts 132b to 132e. The weight part 132 has a substantially clover-like shape when FIG. 2C is viewed from the vertical direction.

  The weight portions 132a to 132e have substantially square cross-sectional shapes (shapes viewed from the XY coordinate plane in FIG. 2C) corresponding to the weight joint portions 112a to 112e, respectively. The weight parts 132a to 132e are joined to the weight joint parts 112a to 112e via the BOX layer 120b. The weight joint 112 is displaced according to the force applied to the weights 132a to 132e, and as a result, the physical quantity can be measured.

  The reason why the weight part 132 is configured as the weight parts 132a to 132 is to achieve both miniaturization and high sensitivity of the physical quantity sensor 100. When the physical quantity sensor 100 is downsized (capacity reduction), the capacity of the weight portion 132 is also reduced and the mass thereof is reduced, so that the sensitivity to the physical quantity is also reduced. The weights 132b to 132e are distributed and arranged so as not to hinder the bending of the flexible parts 113a to 113d, thereby securing the mass of the weight part 132 as a whole. As a result, the physical quantity sensor 100 can be both reduced in size and increased in sensitivity.

  The lower surface of the weight portion 132a (the surface facing the upper surface of the second support substrate 150) functions as a drive electrode E (see FIG. 5) described later. The driving electrode E on the lower surface of the weight portion 132a is capacitively coupled to a driving electrode 154a (see FIG. 5), which will be described later, installed on the upper surface of the second support substrate 150, and between these driving electrodes E-154a. The weight junctions 112a to 112e are vibrated in the Z-axis direction by the voltage applied to the. Details of this drive will be described later.

  The lower surfaces of the weight portions 132b to 132e function as detection electrodes E (see FIG. 5) described later that detect displacements in the X-axis and Y-axis directions of the weight joint portions 112b to 112e, respectively. The detection electrodes E on the back surfaces of the weight portions 132b to 132e are capacitively coupled to detection electrodes 154b to 154e (described later) installed on the upper surface of the second support substrate 150, respectively. In addition, the alphabet part (b-e) of the code | symbol attached | subjected to the weight parts 132b-132e and the electrodes 154b-154e for detection, respectively, is attached | subjected in the same order corresponding to each mutual positional relationship. Details of this detection will be described later.

  2B includes a BOX layer 120a that connects the frame part 111 and the frame part 131, and a BOX layer 120b that connects the weight joint parts 112a to 112e and the weight parts 132a to 132e. The The BOX layer 120 is not connected to the silicon film 110 and the silicon substrate 130 in a portion other than the portion shown in FIG. This is because the flexible portions 113a to 113d can be bent and the weight portion 132 can be displaced.

  In the present embodiment, a structure in which the frame portion 111 of the silicon film 110 and the frame portion 131 of the silicon substrate 130 are joined by the BOX layer 120 is referred to as a frame. In this frame, through wiring portions P (P1 to P10) penetrating vertically are formed. The details of the through wiring portion P (P1 to P10) will be described later. In the case of the physical quantity sensor 100 having an outer shape of 3 mm, the width of the frame is, for example, about 500 μm to 750 μm. For example, a through wiring portion P (P1 to P10) having a diameter of 30 to 100 μm is arranged in this frame. . Moreover, when it is set as the physical quantity sensor 100 whose external shape is 1.5 mm x 1.5 mm, the width | variety of a flame | frame is about 250 micrometers-300 micrometers, for example. The frame width is not particularly limited.

  In FIG. 1, conductive portions 160 to 161 are formed in order to connect the silicon film 110 and the silicon substrate 130 at necessary portions. The conducting part 160 conducts the frame part 111 and the frame part 131 and penetrates the frame part 111 and the BOX layer 120a. The conducting portion 161 conducts the weight joint portion 112 and the weight portion 132, and penetrates the weight joint portion 112a and the BOX layer 120b. For example, the conductive portions 160 to 161 are formed by forming a metal layer such as Al on the edge, wall surface, and bottom of the hole. The shape of the hole is not particularly limited. However, since the metal layer can be effectively formed by Al sputtering or the like, it is preferable to form the holes of the conduction portions 160 to 161 in a forward tapered cone shape.

  Next, the first and second support substrates 140 and 150 will be described with reference to FIG. FIG. 3A is a plan view of the first support substrate 140 as viewed from the lower surface (the surface facing the upper surface of the silicon film 110). The first support substrate 140 has a substantially rectangular parallelepiped outer shape (see FIG. 1), and includes a frame portion 141 and a bottom plate portion 142. The frame portion 141 and the bottom plate portion 142 are formed with a concave portion 143 having a substantially rectangular parallelepiped shape (for example, length 1.0 mm to 1.5 mm, depth 5 μm) so that the weight portion 132 formed on the silicon substrate 130 can be displaced. Has been. The size of the concave portion 143 can be appropriately set (changed) in accordance with a value corresponding to the maximum displacement amount of the weight joint portions 112a to 112e and a desired detection sensitivity.

  The frame portion 141 is a frame-shaped substrate whose outer periphery and inner periphery are both substantially square. The inner periphery and outer periphery of the frame part 141 are the inner periphery and outer periphery of the frame part 111. The bottom plate portion 142 has a substantially square substrate shape whose outer periphery is substantially the same as the frame portion 141. The recess 143 formed in the first support substrate 140 is for securing a space for the weight joint 112 to be displaced.

  A driving electrode 144a and detection electrodes 144b to 144e are disposed on the bottom plate portion 142 (the lower surface of the first support substrate 140) so as to face the weight joint portion 112. The drive electrode 144a and the detection electrodes 144b to 144e can be made of a conductive material. The drive electrode 144a has, for example, a substantially cross shape, and is formed at the center of the recess 143 so as to face the weight joint 112a. The detection electrodes 144b to 144e are substantially square, respectively, surround the drive electrode 144a from four directions, and are sequentially disposed so as to face the weight joint portions 112b to 112e, respectively. The drive electrode 144a and the detection electrodes 144b to 144e are separated from each other.

  A wiring L1 that is electrically connected to the through wiring portion P1 is connected to the driving electrode 144a. Wires L3 to L6 that are electrically connected to the through wiring portions P3 to P6 are connected to the detection electrodes 144b to 144e, respectively. The numerical portions (1, 3 to 6) of the reference numerals attached to the wirings L1, L3 to L6 and the through wiring portions P1, P3 to P6 are attached in the same order corresponding to the mutual positional relationship. Yes.

  For example, a metal material such as Al can be used as a constituent material of the drive electrode 144a, the detection electrodes 144b to 144e, and the wirings L1 and L3 to L6.

  FIG. 3B is a plan view of the second support substrate 150 as viewed from the upper surface (the surface facing the lower surface of the silicon substrate 130). The second support substrate 150 is a substrate having a substantially square outer shape. The frame part 131 of the silicon substrate 130 is bonded to the second support substrate 150. Since the weight part 132 is lower than the frame part 131, it is not joined to the second support substrate 150. This is because a gap is secured between the weight part 132 and the second support substrate 150 and the weight part 132 can be displaced.

  A driving electrode 154 a and detection electrodes 154 b to 154 e are arranged on the upper surface side of the second support substrate 150 so as to face the weight portion 132. The drive electrode 154a and the detection electrodes 154b to 154e can be made of a conductive material. The driving electrode 154a has, for example, a cross shape and is formed near the center of the upper surface of the second support substrate 150 so as to face the weight portion 132a. Each of the detection electrodes 154b to 154e is substantially square, and surrounds the drive electrode 154a from four directions (X-axis positive direction, X-axis negative direction, Y-axis positive direction, and Y-axis negative direction). It is arranged to face 132e. The drive electrode 154a and the detection electrodes 154b to 154e are separated from each other.

  A wiring L2 that is electrically connected to the through wiring portion P2 is connected to the driving electrode 154a. The detection electrodes 154b to 154e are connected to wirings L7 to L10 that are electrically connected to the through wiring portions P7 to P10, respectively. The numerical portions (2, 7 to 10) of the reference numerals attached to the wirings L2, L7 to L10 and the through wiring portions P2, P7 to P10 are attached in the same order corresponding to the mutual positional relationship. Yes.

  For example, a metal material such as Al can be used as a constituent material of the drive electrode 154a, the detection electrodes 154b to 154e, and the wirings L2 and L7 to L10.

  FIG. 3C is a plan view of the second support substrate 150 as viewed from the bottom surface (the surface not facing the bottom surface of the silicon substrate 130). Wiring terminals T (T1 to T11) penetrating the second support substrate 150 are provided on the lower surface of the second support substrate 150, and the outside of the physical quantity sensor 100 (CV conversion circuit or the like) and the drive electrode. 144a and 154a, and detection electrodes 144b to 144e and 154b to 154e can be electrically connected.

  The upper end of the wiring terminal T11 (the end portion facing the lower surface of the silicon substrate 130) is connected to the lower surface of the frame portion 131 and is used to define the potentials of the weight joint portion 112 and the weight portion 132. The wiring terminals T1 to T10 are connected to the through wiring portions P1 to P10, respectively. In addition, the numerical part (1-10) of the code | symbol attached | subjected to the wiring terminals T1-T10 and the penetration wiring parts P1-P10, respectively is attached | subjected in the same order corresponding to the mutual positional relationship.

  For example, the wiring terminals T1 to T11 are formed by forming a metal film such as Al into a tapered conical through hole. The wiring terminals T1 to T11 can be used as connection terminals for connecting to an external circuit (FIG. 9 described later) by wire bonding or the like.

  The through wiring portion P will be described with reference to FIG. FIG. 4A is a cross-sectional view schematically showing the through wiring portion P. FIG. FIG. 4B is a plan view of the through wiring portion P of FIG. 4A viewed from the lower surface side. The through wiring portion P is formed by forming a through hole 170 penetrating up and down the frame and then laminating an insulating layer 171 and a conductive layer 172 in order from the inner wall side of the through hole 170. Insulating layers 171 are also formed on the surfaces of the frame part 111 and the frame part 131 so that the through wiring parts P1 to P10 are electrically independent from each other. The insulating layer 171 may be formed on the entire surface of the frame portion 111 and the frame portion 131, or may be formed by patterning only a region where the wiring L to be connected contacts the frame portion 111 and the frame portion 131. In FIG. 4B, an insulating layer 171 is formed on the surfaces of the frame portion 111 and the frame portion 131, and a conductive layer 172 is formed over the insulating layer 171. When the first support substrate 140 and the second support substrate 150 are joined to the frame, the insulating layer 171 and the conductive layer 172 are formed on the surfaces of the frame portion 111 and the frame portion 131, thereby electrically connecting the wiring L. Making it easy.

  In addition, it is preferable to form a bonding member 180 made of a material capable of bonding the first support substrate 140 and the second support substrate 150 in the outer peripheral region of the frame portion 111 and the frame portion 131. The joining member 180 has a height (height from the upper surface of the frame portion 111 or the lower surface of the frame portion 131) including the insulating layer 171 and the conductive layer 172 formed on the surface of the frame portion 111 and the frame portion 131. More preferably, they are formed approximately equally. By forming the joining member 180 in this way, the parallelism of the sensor gap formed between the upper and lower surfaces of the frame, the lower surface of the first support substrate 140 and the upper surface of the second support substrate 150 can be maintained, and The sealing stability after bonding the first support substrate 140 and the second support substrate 150 to the frame can be improved.

  The insulating layer 171 is made of an inorganic insulating layer such as silicon oxide or silicon nitride. The conductive layer 172 is made of a material such as metal or polycrystalline silicon, and the material can be appropriately selected depending on the material of the first support substrate 140 and the second support substrate 150 to be bonded, the bonding method, and the like. The bonding member 180 is made of a material such as metal or polycrystalline silicon, and the material can be appropriately selected depending on the material of the first support substrate 140 and the second support substrate 150 to be bonded, the bonding method, and the like. When the joining member 180 has a layer configuration substantially the same as that of the through wiring portion P, it can be formed at the same time as the through conduction portion P, and can be separated by patterning by etching, which is advantageous in manufacturing.

  Note that although the conductive layer 172 is illustrated as a layer in FIG. 4A, when the conductive layer 172 is formed of a metal, the conductive layer 172 is used as a power feeding layer and the conductive material is filled into the through-hole 170 by electrolytic plating. It may be the configuration.

<Wiring of physical quantity sensor>
Next, wiring and electrodes of the physical quantity sensor 100 will be described. FIG. 5 is a cross-sectional view of the physical quantity sensor 100 shown in FIG. 1 as viewed from the line AA, and shows six sets of capacitive elements in the physical quantity sensor 100. In FIG. 5, the portion where the weight portion functions as an electrode is indicated by hatching. 5 illustrates six sets of capacitive elements, the above-described physical quantity sensor 100 includes 10 sets of capacitive elements as illustrated in FIGS. 2A and 2B.

  One electrode of the 10 capacitive elements includes a drive electrode 144a and detection electrodes 144b to 144e formed on the first support substrate 140, and a drive electrode 154a and detection electrode 154b formed on the second support substrate 150. ~ 154e. The electrodes facing the electrodes 144a to 144e and 154a to 154e are a driving electrode E formed on the upper surface of the weight joint portion 112a and a detection electrode E formed on the upper surface of the weight joint portions 112b to 112e, respectively. The driving electrode E formed on the lower surface of the weight portion 132a and the detection electrode E formed on the lower surface of the weight portions 132b to 132e.

  The capacitance of the capacitive element is inversely proportional to the distance between the electrodes. In the present embodiment, it is considered that the drive electrode E and the detection electrode E are on the upper surface of the weight joint 112 and the lower surface of the weight 132. The drive electrode E and the detection electrode E are not separately formed on the upper surface of the weight joint 112 or the surface layer of the lower surface of the weight 132. The upper surface of the weight joint 112 and the lower surface of the weight 132 are regarded as functioning as the drive electrode E and the detection electrode E.

  The driving electrode 144a and the detection electrodes 144b to 144e formed on the first support substrate 140 are sequentially connected to the through wiring portions P1, P3 to P6 via the wirings L1, L3 to L6 (see FIG. 3A), respectively. (See FIG. 2A). The driving electrode 154a and the detection electrodes 154b to 154e formed on the second support substrate 150 are sequentially connected to the through wiring portions P2, P7 to P10 via the wirings L2, L7 to L10 (see FIG. 3B), respectively. (See FIG. 2A). In FIG. 5, a portion where the detection electrode 144e is electrically connected to the through wiring portion P1 via the wiring L1, and a detection electrode 154c is electrically connected to the through wiring portion P2 via the wiring L2. The part which has been shown. In FIG. 5, the through wiring portions P1 and P2 show a case where the through holes are filled with a conductive material.

  The wirings connected to the outside for the driving electrodes 144a and 154a and the detection electrodes 144b to 144e and 154b to 154e may be connected to the lower surfaces of the through wiring portions P1 to P10. The wiring terminals T1 to T10 shown in FIG. 3C are arranged at positions facing the lower surface of the frame part 131 in which the through wiring parts P1 to 10 are formed, respectively. The wiring terminal T11 shown in FIG. 3C is arranged at a position facing the lower surface of the frame part 131 at the position where the conduction part 160 is formed.

  As described above, the wiring terminals T1 to T10 are electrically connected to the driving electrodes 144a and 154a and the detection electrodes 144b to 144e and 154b to 154e through the through wiring portions P1 to P10, respectively.

  The drive electrode E and the detection electrode E are formed on the upper surface of the weight joint 112 and the lower surface of the weight 132, respectively. The weight joint portion 112 and the weight portion 132 are electrically connected via the conductive portion 161, and both are made of a conductive material. The frame part 131 and the frame part 111 are electrically connected via the conductive part 160, and both are made of a conductive material. The weight joint portion 112, the flexible portion 113, and the frame portion 111 are integrally formed of a conductive material. Therefore, the wiring for the drive electrode E and the detection electrode E may be connected to the lower surface of the frame portion 131. Since the wiring terminal T11 is disposed on the lower surface of the frame portion 131 facing the conduction portion 160, the wiring terminal T11 is electrically connected to the driving electrode E and the detection electrode E.

<Operation of physical quantity sensor>
As described above, in the physical quantity sensor 100, the weight portion in which the weight joint portion 112 and the weight portions 132 (132 a to 132 e) are integrally formed is supported by the flexible portion 113 having flexibility extending from the frame portion 111. The first support substrate 140, the second support substrate 150, and the semiconductor substrate W are configured to be displaceable.

  When the physical quantity sensor 100 is used as an acceleration sensor, it is only necessary to detect the displacement of the weight caused by the action of acceleration. For example, if acceleration in the X-axis positive direction is applied to the weight part, the weight part is displaced in the X-axis positive direction by an external force corresponding to the acceleration. The amount of displacement at this time depends on the magnitude of the acting acceleration. Therefore, if the displacement of the weight portion in the X-axis, Y-axis, and Z-axis directions is detected, the acceleration value of each axial component can be obtained. In the physical quantity sensor 100, the acceleration value of each axial component can be detected by detecting the change in the capacitance of the capacitive element formed by the weight portion and the electrode.

  When the physical quantity sensor 100 is used as an angular velocity sensor, the weight 132 is caused to vibrate up and down by a driving electrode (generally, an AC voltage is applied to make a single vibration), and the displacement of the weight caused by the action of the angular velocity is detected. do it. For example, when the angular velocity ω is applied while the weight portion is moving in the Z-axis direction at the speed vz, the Coriolis force F acts on the weight portion 132. Specifically, according to the angular velocity ωx in the X-axis direction and the angular velocity ωy in the Y-axis direction, the Coriolis force Fy (= 2 · m · vz · ωx) in the Y-axis direction and the Coriolis force Fx (= 2 · m · vz · ωy) acts on the weight portion 132 (m is the mass of the weight portion 132). When the Coriolis force Fy due to the angular velocity ωx in the X-axis direction is applied, an inclination in the Y direction occurs at the weight joint 112. As described above, the weight joint 112 is inclined (displaced) in the Y direction and the X direction by the Coriolis forces Fy and Fx caused by the angular velocities ωx and ωy. Therefore, by detecting the displacement of the weight portion 132 in each axial direction, the value of the angular velocity of each axial component can be obtained. In the physical quantity sensor 100, the value of the angular velocity of each axial component can be detected by detecting the change in the capacitance of the capacitive element formed between the weight part 132 and each electrode.

  In FIG. 5, when a voltage is applied between the drive electrodes 144a and E, the drive electrodes 144a and E are attracted to each other by the Coulomb force, and the weight portions (the weight joint portion 112 and the weight portion 132) are displaced in the positive direction of the Z axis. . In FIG. 5, when a voltage is applied between the driving electrodes 154a and E, the driving electrodes 154a and E are attracted to each other by the Coulomb force, and the weight joint portion 112 (also the weight portion 132) is displaced in the Z-axis negative direction. . That is, by alternately applying a voltage between the drive electrodes 144a and E and between the drive electrodes 154a and E, the weight joint portion 112 (also the weight portion 132) vibrates in the Z-axis direction. The voltage can be applied using a positive or negative direct current waveform (a pulse waveform when considering non-application), a half-wave waveform, or the like. The period of vibration of the weight joint 112 is determined by the period for switching the voltage. This switching cycle is preferably close to the natural frequency of the weight joint 112 to some extent. The natural frequency of the weight portion is determined by the elastic force of the flexible portion 113, the mass of the weight portion 132, and the like. If the period of vibration applied to the weight portion does not correspond to the natural frequency, the energy of vibration applied to the weight portion is diffused and energy efficiency is reduced. Note that an AC voltage having a frequency half that of the natural frequency of the weight may be applied only to either the drive electrodes 144a and E or between the drive electrodes 154a and E.

  In general, the angular velocity signal is several kHz or more, and the acceleration signal has a frequency two or more digits lower than the angular velocity signal, so that each can be identified by an external signal processing circuit. In other words, the acceleration and angular velocity are processed by the filter circuit for the low frequency component (or bias component) and the signal following the vibration frequency by the signal processing circuit provided outside, and each signal after the processing is detected. It is possible to detect the acceleration in the triaxial (X, Y, Z) direction and the angular velocity in the biaxial (X, Y) direction. That is, by using the physical quantity sensor 100 as one sensor element, it is possible to detect the acceleration in the triaxial (X, Y, Z) direction and the angular velocity in the biaxial (X, Y) direction. Further, the physical quantity sensor 100 can be used as a sensor that detects only acceleration / angular velocity. The physical quantity sensor 100 described in the present embodiment can detect the acceleration in the three-axis (X, Y, Z) direction and the angular velocity around the two axes (X, Y). In the case of detecting acceleration in the three-axis direction, the drive electrodes 144a and 154a described above function as detection electrodes for detecting acceleration in the Z-axis direction.

<Method for Manufacturing Physical Quantity Sensor 100>
Hereinafter, the manufacturing method of the physical quantity sensor 100 will be described with reference to FIGS. 6 (A) to 6 (D) and FIGS. 7 (A) to (C).
(1) Preparation of semiconductor substrate W (see FIG. 6A)
A semiconductor substrate W (SOI substrate) formed by stacking a silicon film 110, a BOX layer 120, and a silicon substrate 130 is prepared. As described above, the silicon film 110 is a layer constituting the frame part 111, the weight joint part 112, and the flexible part 113. The BOX layer 120 is a layer that joins the silicon film 110 and the silicon substrate 130 and functions as an etching stopper layer. The silicon substrate 130 is a layer constituting the frame part 131 and the weight part 132. The semiconductor substrate W is produced by SIMOX or a bonding method.

(2) Processing of silicon film 110 (see FIG. 6B)
By forming a mask for processing the frame portion 111, the weight joint portion 112, the flexible portion 113, the opening 114, and the through hole 170, and etching the silicon film 110 through the mask, the frame portion 111, the weight joint A portion 112, a flexible portion 113, and an opening 114 are formed. As an etching method, a RIE (Reactive Ion Etching) method can be used.

(3) Processing of silicon substrate 130 (see FIG. 6C)
By etching the silicon substrate 130 on which a predetermined mask is formed, openings for determining processing positions of the frame portion 131, the weight portion 132, the through hole 170, and the gap 190 are formed, and the silicon substrate 130 is formed. As an etching method, an etching method called DRIE (Deep Reactive Ion Etching) can be used. In DRIE, the etching process that digs while eroding the material layer in the thickness direction and the deposition process that forms a polymer wall on the side of the dug hole can be repeated alternately, allowing erosion to proceed almost only in the thickness direction. Become. In this case, an etching material having etching selectivity between silicon oxide and silicon may be used. For example, a mixed gas of SF ₆ gas and O ₂ gas may be used in the etching stage, and C ₄ F ₈ gas may be used in the deposition stage.

(4) Processing of BOX layer 120 (see FIG. 6D)
The unnecessary BOX layer 120 is etched with respect to the silicon film 110 and the silicon substrate 130. As a result, the BOX layers 120a and 120b (see FIG. 2B) necessary only between the frame portion 111 and the frame portion 131 and between the weight joint portion 112 and the weight portion 132 are left. As an etching method, wet etching using buffered hydrofluoric acid (for example, a mixed aqueous solution of HF = 5.5 wt% and NH ₄ F = 20 wt%) can be given. Further, dry etching by the RIE method using a mixed gas of CF ₄ gas and O ₂ gas is also applicable.

(5) Formation of conductive portions 160 to 161 (see FIG. 7A)
For example, Al is deposited by an evaporation method, a sputtering method, or the like on the opening 114 (see FIG. 6D) penetrating the silicon film 110 and the BOX layer 120b to form the conductive portions 160 to 161. Unnecessary metal layers deposited on the upper surface of the silicon film 110 (metal layers outside the upper edges (not shown) of the conductive portions 160 to 161) are removed by etching.

(6) Formation of penetration wiring part P (refer to Drawing 4 and Drawing 7 (B))
The through wiring portion P is performed by the following 1) to 2).
1) Formation of Insulating Layer 171 An insulating layer 171 is formed in the through hole 170 and in predetermined regions on the respective surfaces of the silicon film 110 and the silicon substrate 130. As the insulating layer 171, for example, silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), or the like can be used. In the case of silicon oxide, a thermal oxidation method or a CVD (Chemical Vapor Deposition) method can be used. In the case of silicon nitride, a CVD method can be used. In the present embodiment, silicon oxide is deposited with a thickness of 0.5 μm on the inside of through-hole 170 and each surface (upper surface and lower surface) of silicon film 110 and silicon substrate 130 by CVD. (See FIG. 4). Thereafter, the unnecessary insulating layer 171 on each surface of the silicon film 110 and the silicon substrate 130 is patterned (removed) by etching using a dry film resist mask.

2) Formation of conductive layer 172 (see FIGS. 4 and 7B)
When the conductive layer 172 having conductivity is disposed inside the through hole 170, it is preferable to use a CVD (Chemical Vapor Deposition) method or an electrolytic plating method in consideration of film formation on the inner wall of the through hole 170. For example, a conductive layer 172 made of polycrystalline silicon (Poly-Si) is deposited to a thickness of 0.5 μm on the inner wall of the through-hole 170 and the surfaces of the silicon film 110 and the silicon substrate 130 by the CVD method ( (See FIG. 4). A portion (not shown) where the conductive layer 172 is not required on each surface (upper surface and lower surface) of the silicon film 110 and the silicon substrate 130 is protected with a resist or the like, and after forming the conductive layer 172 in the through hole 170, The unnecessary conductive layer is removed by lifting off. As the conductive layer 172, for example, a metal material (Ti, Cu, or the like) can be used in addition to polycrystalline silicon. In this case, polycrystalline silicon, Al, or the like is formed at the contact point between the first support substrate 140 and the second support substrate 150 later. Through the above manufacturing method, the through wiring portion P (P1 to P10) is formed in the semiconductor substrate W.

  At this time, it is preferable to form the joining member 180 (see FIG. 4) with the same material as the conductive layer along the outer periphery of the frame part 111 and the frame part 131. In the above-described manufacturing method, the bonding member 180 can be formed by patterning the insulating layer and the conductive layer in the outer peripheral region of each surface of the silicon film 110 and the silicon substrate 130.

(7) Bonding of the first support substrate 140 and the second support substrate 150 (see FIG. 7C)
The joining of the first support substrate 140 and the second support substrate 150 is performed by the steps shown in the following 1) to 4).

1) Creation of the 1st support substrate 140 The 1st support substrate 140 is comprised from either a glass material, a semiconductor, a metal material, and an insulating resin material. A case where a glass material is used as the first support substrate 140 will be described. A glass substrate containing so-called mobile ions (so-called Pyrex (registered trademark) glass) is used. In the case where the first support substrate 140 is made of a glass material, for example, the recess 143 is formed by etching a glass substrate containing movable ions. Next, the driving electrode 144a, the detection electrodes 144b to 144e, and the wirings L1, L3 to L6 are formed in, for example, a pattern made of Al at positions facing the weight joint portions 112a to 112e in the recess 143 (FIG. 3 (A)).

2) Creation of the second support substrate 150 The second support substrate 150 can be made of substantially the same material as the first support substrate 140 described above. In this embodiment, the case where a glass substrate is used as the second support substrate 150 will be described. The driving electrode 154a, the detection electrodes 154b to 154e, and the wirings L2 and L8 to L11 are formed with, for example, a pattern made of Al at positions facing the weight parts 132a to 132e of the glass substrate containing movable ions ( (See FIG. 3B). In addition, the second support substrate 150 is etched or sandblasted so that tapered conical through holes for forming wiring terminals T1 to T11 are formed at positions corresponding to the through wiring portions P1 to P10 and the conduction portion 160, respectively. Individually formed (see FIGS. 7C and 3C).

3) Joining of the semiconductor substrate W, the first support substrate 140, and the second support substrate 150 The first support substrate 140, the second support substrate 150, and the semiconductor substrate W are joined by anodic bonding.

4) Formation of wiring terminals T1 to T11 In the upper surface of the second support substrate 150 and the conical through hole, for example, a metal layer is formed in the order of a Cr layer and an Au layer by vapor deposition or sputtering. Unnecessary metal layers (metal layers outside the upper edge of the wiring terminals T (T1 to T11)) are removed by etching to form wiring terminals T1 to T11 (FIGS. 7C and 3C). )reference). The wiring terminals T1 to T11 may be formed before bonding to the semiconductor substrate W.

  According to the manufacturing method described above, since the first support substrate 140 and the second support substrate 150 are joined after the processing of the semiconductor substrate W, the SOI substrate can be handled in the manufacturing process. For this reason, it is difficult for foreign matters (resist, deposition deposits during DRIE, etc.) to remain inside the sensor. Therefore, the physical quantity sensor 100 with high reliability can be provided.

(8) Dicing of the semiconductor substrate W, the first support substrate 140, and the second support substrate 150 The semiconductor substrate W, the first support substrate 140, and the second support substrate 150 bonded to each other are cut with a dicing saw or the like. The physical quantity sensor 100 is separated. The physical quantity sensor 100 can be manufactured as described above.

  Hereinafter, as modifications 1 to 3 of the present embodiment, a case where the material of the support substrate (including the first support substrate 140 and the second support substrate 150) is changed will be described.

<Modification 1>
A case where a semiconductor material is used as the support substrate will be described. As the semiconductor material, it is preferable to use a silicon substrate which is substantially the same material as the semiconductor substrate W. A substrate provided with an insulating layer (for example, silicon oxide) on the surface of the silicon substrate (not shown) facing the weight joint 112 or the weight 132 is used. The silicon substrate and the semiconductor substrate W can be bonded by a direct bonding method such as a plasma bonding method. Alternatively, a part of the joining member is formed in a predetermined region on the insulating substrate in the order of Cr, Au (or Au—Sn, Ag—Sn) on the insulating layer side. By forming a part of the joining member in the order of Ti and Au on the sensor side (on the conductive layer 172 exposed on the surface of the frame part 111 and the frame part 131), a metal joint such as Au—Au is used. The silicon substrate as the support substrate and the semiconductor substrate W can be bonded.

  When a silicon substrate is used as the support substrate, it is not necessary to replace the blade during dicing. In other words, conventionally, a suitable blade is selected depending on the material of the layer to be diced, whereas in the first modification, dicing can be performed collectively with the same blade. Therefore, production efficiency is improved. Further, conventionally, when a blade is selected for each layer, the blade width must be reduced from the largest to the smallest in the order in which dicing is performed, and when the physical quantity sensor 100 is manufactured by wafer multi-faceting, the area of the dicing region Is unnecessarily large, accounting for about 30%, and imposition efficiency is not good. According to the first modification, dicing can be performed at once by the same blade, so that the area of the dicing region can be reduced and the imposition efficiency can be increased.

<Modification 2>
A case where a metal material is used as the support substrate will be described. As the metal material, stainless steel, invar, or the like can be used. A substrate provided with an insulating layer (for example, insulating resin or silicon oxide) on the surface of the metal plate (not shown) facing the weight joint 112 or the weight 132 is used. For joining the metal plate and the semiconductor substrate W, metal joining can be used. For example, a part of the joining member is formed in the order of Ti and Au on the sensor side (on the conductive layer 172 exposed on the surface of the frame part 111 and the frame part 131). On the metal plate side, a part of the joining member is formed in a predetermined region in the order of Cr, Au (or Au—Sn, Ag—Sn) on the insulating layer. Next, metal bonding is performed using Au on the sensor side and Au on the metal plate side as contacts. When a metal plate is used as the support substrate, a metal plate having a thickness of 50 μm or less can be used because of material strength, and the sensor can be thinned. When a metal material is used as the support substrate, it is necessary to form an insulating layer on the inner wall of the conical through hole after the conical through hole corresponding to the wiring terminal T is formed by etching or the like.

<Modification 3>
A case where an insulating resin material is used as the support substrate will be described. As the insulating resin material, it is preferable to use polyimide resin, epoxy resin, or the like. Metal bonding can be used for bonding the support substrate and the semiconductor substrate W. For example, a part of the joining member is formed in the order of Ti and Au on the conductive layer 172 exposed on the surfaces of the frame part 111 and the frame part 131. On the insulating resin substrate side, a part of the joining member is formed in a predetermined region in the order of Cr, Au (or Au—Sn, Ag—Sn) on the insulating layer. Next, metal bonding is performed using Au on the sensor side and Au on the insulating resin substrate side as contacts.

  As described above, in the physical quantity sensor 100, by providing the through wiring portions P1 to P10 in the frame portions 111 and 131 of the semiconductor substrate W, the formation region of the weight portion 132 and the electrodes 144a to 144e, 154a to 154e, E can be obtained. It is also possible to connect the wirings L1 to L10 so as not to interfere. For this reason, the volume of the weight part 132 can be secured, and the displacement amount of the weight part 132 in the X, Y, and Z-axis directions can be secured. For this reason, size reduction of the external size of the physical quantity sensor 100 can be achieved without deteriorating the sensor performance. Therefore, the external size of the entire physical quantity sensor 100 can be reduced to about ¼ compared to the overall external size of the conventional physical quantity sensor. In addition, when the physical quantity sensor 100 has the same external size as the conventional physical quantity sensor and the volume of the weight portion is increased, the sensitivity as the physical quantity sensor can be improved.

  In recent years, mounting height has become a problem when a physical quantity sensor is mounted on an electronic device. However, in the physical quantity sensor according to the present invention, even if the semiconductor substrate W is thinned (the weight portion is thinned), the weight portion has a larger volume than the conventional one, and compensates for sensitivity reduction due to the thinning. Can do.

  The physical quantity sensor 100 according to the embodiment of the present invention is mounted on a circuit board on which an active element such as an IC is mounted, for example, and is a wiring terminal T (T1 to T11) by a known method and material such as wire bonding connection. By connecting an electronic circuit board or an active element such as an IC, the physical quantity sensor and the electronic circuit can be provided as one electronic component. This electronic component can be distributed in the market by being mounted on a mobile terminal such as a game machine or a mobile phone.

  Hereinafter, a processing circuit that processes displacement signals of acceleration and angular velocity detected by the physical quantity sensor 100 will be described.

<Processing circuit>
A configuration example of each processing circuit that processes displacement signals of acceleration and angular velocity detected by the physical quantity sensor 100 will be described with reference to FIG.

  FIG. 8 is a diagram illustrating a circuit configuration of a processing circuit 300 that processes displacement signals of acceleration and angular velocity detected by the physical quantity sensor 100. In FIG. 8, the processing circuit 300 includes a CV converter 301, an amplifier circuit (Amp) 302, and a filter circuit 303.

  The CV converter 301 converts each axial displacement signal (capacitance change) output from the physical quantity sensor 100 according to the applied acceleration and angular velocity into a voltage signal and outputs the voltage signal to the amplifier circuit 302. The amplifier circuit 302 amplifies the voltage signal input from the CV converter 301 with a predetermined amplification factor and outputs the amplified signal to the filter circuit 303. The filter circuit 303 has a filter function that allows a signal component of several kHz or more to pass therethrough. The filter circuit 303 passes a signal component of several kHz or more from the voltage signal amplified by the amplifier circuit 302 and outputs it as an angular velocity detection signal in the X-axis direction and the Y-axis direction. The filter circuit 303 outputs a low-frequency signal component as an acceleration detection signal in the X-axis direction, the Y-axis direction, and the Z-axis direction.

  Next, an example of a semiconductor device in which the physical quantity sensor 100 and the processing circuit 300 are mounted will be described. Note that in this specification, a semiconductor device refers to all devices that can function using semiconductor technology, and electronic components and electronic devices are also included in the scope of the semiconductor device.

  FIG. 9 is a diagram illustrating an example of a sensor module 400 as a semiconductor device on which the physical quantity sensor 100 and the processing circuit 300 are mounted. In the sensor module 400, a signal processing chip 401 including the processing circuit 300, a memory chip 402, and a sensor chip 403 including the physical quantity sensor 100 are mounted on a substrate 404. Each chip 401, 402, 403 is connected by a bonding wire 405. The memory chip 402 is a memory that stores a control program, parameters, and the like for the signal processing chip 401.

  Providing the sensor module 400 as described above facilitates mounting on a mobile terminal such as a game machine or a mobile phone.

  Next, an example in which the sensor module 400 shown in FIG. 9 is mounted as an electronic device, for example, in a mobile terminal will be described.

  FIG. 10 is a diagram illustrating an example of the portable information terminal 500 in which the sensor module 400 is mounted. In FIG. 10, the portable information terminal 500 includes a display unit 501 and a keyboard unit 502. The sensor module 400 is mounted inside the keyboard unit 502. The portable information terminal 500 has a function of storing various programs therein and executing communication processing, information processing, and the like by the various programs. In this portable information terminal 500, by using the acceleration and angular velocity detected by the sensor module 400 in the application program, for example, it is possible to add a function of detecting the acceleration at the time of dropping and turning off the power. become.

  By mounting the sensor module 400 on the mobile terminal as described above, a new function can be realized, and the convenience and reliability of the mobile terminal can be improved.

It is a disassembled perspective view which shows the state which decomposed | disassembled the physical quantity sensor which concerns on one embodiment of this invention. 1A is a plan view showing the top surface of a silicon film, FIG. 2B is a plan view showing the top surface of a BOX layer, and FIG. 2C is a plan view showing the top surface of the silicon substrate. . It is a figure which shows the structure of a support substrate, (A) is a top view which shows the lower surface of a 1st support substrate, (B) is a top view which shows the upper surface of a 2nd support substrate, (C) is the lower surface of a 2nd support substrate. FIG. It is a figure which shows typically the penetration wiring part formed in a semiconductor substrate, (A) is sectional drawing which shows the structure of a penetration wiring part, (B) is a top view which shows the structure of a penetration wiring part. It is sectional drawing which shows the structure of the capacitive element formed in a physical quantity sensor. It is a figure which shows the manufacturing method of a physical quantity sensor, (A) is sectional drawing which shows the semiconductor substrate before a process, (B) shows the process of forming a frame part, a weight junction part, a flexible part, and opening in a semiconductor substrate. Sectional drawing, (C) is a sectional view showing a step of forming a frame portion and a weight portion on a semiconductor substrate, and (D) is a sectional view showing a step of forming a through hole in the semiconductor substrate. It is a figure which shows the manufacturing method of a physical quantity sensor, (A) is sectional drawing which shows the process of forming a conduction | electrical_connection part in a semiconductor substrate, (B) is sectional drawing which shows the process of forming a penetration wiring part in a semiconductor substrate, (C ) Is a cross-sectional view showing a process of bonding a first support substrate and a second support substrate to a semiconductor substrate and forming wiring terminals on the second support substrate. It is a figure which shows an example of the angular velocity processing circuit which processes the displacement signal of the angular velocity detected by a physical quantity sensor. It is a figure which shows an example of the sensor module which mounted the physical quantity sensor and the processing circuit. It is a figure which shows an example of the mobile terminal which mounted the sensor module.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 ... Physical quantity sensor, 110 ... Silicon film, 111, 131 ... Frame part, 112 (112a-112e) ... Weight junction part, 113 ... Flexible part, 120 ... BOX layer, 130 ... Silicon substrate, 132 (132a-132e) ... weight portion, 140 ... first support substrate, 144a, 154a ... drive electrode, 144b-144e, 154b-154e ... detection electrode, 150 ... second support substrate, 160, 161 ... conduction portion, 170 ... through hole, 171 ... Insulating layer, 172 ... Conductive layer, 180 ... Joint member, 190 ... Gap, 300 ... Processing circuit, 400 ... Sensor module, 500 ... Portable information terminal, L1, L2 ... (connected to driving electrode) wiring, E ... Driving electrode (of weight part), detection electrode, L3-L10 ... wiring (connected to detection electrode), T1-T11E ... line terminal, P1-P1 ... through the wiring portion

Claims (6)

A semiconductor substrate comprising a frame portion, a weight portion disposed inside the frame portion, and a flexible portion connecting the weight portion and the frame portion;
A first support substrate joined to one side of the frame portion;
A second support substrate joined to the other side of the frame portion;
A wiring terminal provided on at least one of the first support substrate and the second support substrate and electrically conducting one side and the other side of the first support substrate or the second support substrate;
A first electrode provided on the first support substrate and facing the weight portion;
A second electrode provided on the second support substrate and facing the weight portion;
The frame portion is provided with a through wiring portion that conducts between one side and the other side of the frame portion, and the through wiring portion and the wiring terminal are electrically connected to each other. Sensor.   The first electrode and the second electrode include a detection electrode for detecting a change in capacitance of a capacitive element formed between the first electrode and the second electrode and the weight portion, and the weight portion. The physical quantity sensor according to claim 1, further comprising a drive electrode that is driven to vibrate.   A joining member that joins the frame portion and the first support substrate, or the frame portion and the second support substrate is between the frame portion and the first support substrate, or the frame portion and the first support substrate. The physical quantity sensor according to claim 1, wherein the physical quantity sensor is disposed between the two support substrates. The through wiring portion includes a through hole penetrating one side and the other side of the frame portion, an insulating layer formed in the through hole and in a peripheral region of the opening of the through hole, and on the insulating layer. A conductive layer formed,
The physical quantity sensor according to claim 1, wherein the through wiring portion and the wiring terminal are electrically connected by the conductive layer. A semiconductor substrate is formed with a frame portion, a weight portion disposed inside the frame portion, and a flexible portion connecting the weight portion and the frame portion,
Forming a through-hole penetrating one side and the other side of the frame part in a partial region of the frame part;
A through wiring portion that forms an insulating layer and a conductive layer disposed on the insulating layer in the through hole and in a peripheral region of the opening of the through hole, and that conducts one side and the other side of the frame portion Form the
Forming a first electrode and a wiring electrically connected to the first electrode on a first support substrate bonded to one side of the frame portion;
Forming a second electrode and a wiring electrically connected to the second electrode on a second support substrate bonded to the other side of the frame portion;
Bonding the first support substrate and one side of the frame portion with the weight portion and the first electrode facing each other;
The second support substrate and the other side of the frame part are joined with the weight part and the second electrode facing each other,
Forming a wiring terminal provided on at least one of the first support substrate and the second support substrate and electrically connecting one side and the other side of the first support substrate or the second support substrate;
A method of manufacturing a physical quantity sensor, wherein the through wiring portion and the wiring terminal portion are electrically connected via the wiring formed on the first support substrate and the second support substrate. The physical quantity sensor according to any one of claims 1 to 4,
A processing circuit for processing a physical quantity detection signal detected by the physical quantity sensor;
A semiconductor device comprising:

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