JP2003344444A - Semiconductor acceleration sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor acceleration sensor capable of preventing generation of a defective product at the wire bonding time or at the sealing time of a bonding wire. <P>SOLUTION: In the semiconductor acceleration sensor body 1, a frame part 11 having a rectangular frame shape is provided, and an overlapping part 12 is arranged inside the frame part 11, and one side around the overlapping part 12 is connected to the frame part 11 continuously and integrally through a flexible part 13 thinner than the frame part 11. Each gauge resistance 15 formed on the flexible part 13 is connected to a pad 16 through diffusion layer wiring 17 and metal wiring 21. The frame part 11 is formed in the rectangular frame shape by a support frame 11a for supporting the overlapping part 12 in an open-sided shape, a pad frame 11b formed in parallel with the support frame 11a and having a plurality of pads 16 formed thereon, and a pair of side frames 11c, 11d for connecting respectively each left end and each right end of the support frame 11a and the pad frame 11b on right and left both sides of the overlapping part 12. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to, for example, an automobile,
The present invention relates to a semiconductor acceleration sensor used in aircrafts, home appliances and the like.

[0002]

2. Description of the Related Art Conventionally, there are known acceleration sensors that detect mechanical strain as a change in electric resistance and a sensor that detects mechanical strain as a change in capacitance. As an acceleration sensor that detects a change, a semiconductor acceleration sensor formed using a semiconductor manufacturing technique is provided.

As a semiconductor acceleration sensor of this type, for example, as shown in FIG. 19, an SOI (Silicon) having a buried insulating layer 102 made of a silicon oxide film in an intermediate portion in the thickness direction is used.
There is a structure in which glass covers 2 and 3 are laminated on both surfaces in the thickness direction of the semiconductor acceleration sensor body 1 formed using the conOn Insulator) substrate 100. In addition, S
The OI substrate 100 includes a support layer 101 made of a silicon layer (silicon substrate) and an active layer 103 made of an n-type silicon layer.
And a buried insulating layer 102 is formed between the two.

As shown in FIGS. 19 and 20, the semiconductor acceleration sensor body 1 is provided with a rectangular frame-shaped frame portion 11 ′, a weight portion 12 is arranged inside the frame portion 11 ′, and a weight portion 12 is provided. One side around the frame 1
The frame portion 1 through the flexible portion 13 which is thinner than 1 '
1'has a structure that is continuously and integrally connected. Therefore, a slit 14 is formed around the weight portion 12 between the weight portion 12 and the frame portion 11 ′ except for the bending portion 13. Further, the flexible portions 13 are formed at two locations apart from each other in the direction along one side of the weight portion 12. Each of the flexures 13 is provided with two gauge resistors 15 as strain detecting elements. The gauge resistor 15 is a piezoresistor and is connected by a diffusion layer wiring 17 so as to form a bridge circuit. Further, the pad 16 that serves as each terminal of the bridge circuit is a portion where the flexible portion 13 is connected in the frame portion 11 '(that is, a portion relatively close to the flexible portion 13).
Is formed in.

Therefore, when an external force (that is, acceleration) including a component in the thickness direction of the semiconductor acceleration sensor body 1 is applied, the frame portion 11 'and the weight portion 12 are caused to have a thickness of the semiconductor acceleration sensor body 1 by the inertia of the weight portion 12. As a result, the bending portion 13 bends as a result, and the resistance value of the gauge resistor 15 changes. That is, the acceleration acting on the semiconductor acceleration sensor body 1 can be detected by detecting the change in the resistance value of the gauge resistor 15. In this semiconductor acceleration sensor main body 1, the weight portion 12 is provided with a frame portion 11 ′ through a bending portion 13 as a cantilever.
It is supported by a cantilever. The semiconductor acceleration sensor shown in FIG. 19 constitutes a so-called cantilever type semiconductor acceleration sensor, but a double-supported beam type semiconductor acceleration sensor is also known.

A glass cover 2 is joined to the main surface side of the semiconductor acceleration sensor body 1 (upper surface side in FIG. 19), and a glass cover 2 is bonded to the back surface side (lower surface side in FIG. 19) of the semiconductor acceleration sensor body 1. The cover 3 is joined. The space formed between the cover 2 and the cover 3 is not hermetically sealed, but when the weight portion 12 moves relative to the frame portion 11 ′, a braking force (air) against the weight portion 12 ( When the so-called air dump acts and excessive acceleration (acceleration of several thousand G, for example) is applied, the amount of movement of the weight portion 12 is regulated to prevent the bending portion 13 from being broken. Weight part 1 on both covers 2 and 3
Recesses 2a and 3a for securing the moving range of the weight portion 12 are formed on the surface facing 2 respectively. Further, in both covers 2 and 3, protrusion-shaped stoppers 2b and 3b for restricting the movement amount of the weight portion 12 are integrally formed on the inner bottom surfaces of the recesses 2a and 3a, respectively, and the weight portion 12 is subjected to acceleration. The moving amount of the weight portion 12 when the stopper 2b,
The breakage of the flexible portion 13 is prevented by regulating the distance 3b.

By the way, the semiconductor acceleration sensor body 1 is
The insulating layer 18 is formed on the main surface of the active layer 103 (note that the insulating layer 18 is not shown in FIG. 20), and the above-mentioned pad 16 is formed in the contact hole formed in the insulating layer 18. It is connected to the diffusion layer wiring 17 via a metal wiring 21 made of Ai-Si having a buried portion and a contact portion 23 between the metal wiring 21 and the diffusion layer wiring 17. Further, in the semiconductor acceleration sensor body 1, Al-Si is formed on the insulating layer 18 and on the portions of the frame portion 11 ′ that overlap the portions parallel to the extension direction of the bending portion 13.
The bonding layer 22 made of is formed. The insulating layer 1
Reference numeral 8 is composed of a silicon oxide film on the main surface of active layer 103 and a silicon nitride film formed on this silicon oxide film.

The peripheral portion of the cover 3 on the back surface of the semiconductor acceleration sensor body 1 is joined to the back surface of the semiconductor acceleration sensor body 1 by anodic bonding. On the other hand, the cover 2 on the main surface side of the semiconductor acceleration sensor body 1 is the semiconductor acceleration sensor body 1
Of the frame portion 11 ′ is anodically bonded to the main surface side of the semiconductor acceleration sensor body 1 through the bonding layers 22 formed on the surface sides of the portions parallel to the extension direction of the bending portion 13, and the extension direction of the bending portion 13 is formed. A gap is formed between the part and the part orthogonal to. That is, the frame portion 11 'is
If the vertical direction of FIG. 20 is defined as the horizontal direction, the weight portion 12
A frame 11a 'supporting the cantilever and a frame 11a
a frame 11b 'parallel to a', and a pair of side frames 11c ', 1 connecting left and right ends of both frames 11a', 11b 'on the left and right sides of the weight portion 12, respectively.
1d 'and a rectangular frame shape.
A gap is formed between the insulating layer 18 on the a ′ and 11 b ′ and the cover 2.

An example of a method of manufacturing the above semiconductor acceleration sensor will be briefly described below. In the SOI wafer described below, a large number of semiconductor acceleration sensor bodies 1 are finally formed, a large number of covers 2 are formed in advance on the first glass substrate, and a large number of them are formed in advance on the second glass substrate. The cover 3 is formed.

First, the active layer 1 on the main surface side of the SOI wafer
After the diffusion layer wiring 17 and the gauge resistor 15 are sequentially formed on the silicon wafer 03, a silicon oxide film is formed on the entire main surface and the back surface of the SOI wafer, and then silicon is formed on the entire main surface side and the back surface side of the SOI wafer. Form a nitride film. The impurity concentration of the diffusion layer wirings 17 ^{10 2 0}
It is set to about cm ^−3, and when forming the diffusion layer wiring 17, drive-in is performed after pre-deposition of p-type impurities (for example, boron) on the surface of the active layer 103 by ion implantation. Drive-in is 110
The temperature is set to about 0 ° C.

Next, the slit 14 is formed on the SOI wafer.
The silicon nitride film and the silicon oxide film on the back surface side of the SOI wafer are patterned in order to make the portion corresponding to the bending portion 13 thinner than other portions. Subsequently, using each silicon nitride film as a mask, S is performed until the thickness of the portion corresponding to each of the slit 14 and the bending portion 13 in the SOI wafer reaches a predetermined thickness (for example, about 10 μm).
The OI wafer is etched from the back side. In addition, in this etching, KOH (potassium hydroxide), TMAH
(Tetramethylammonium aqueous solution), anisotropic etching using an alkaline solution such as EDP (ethylenediaminepyrocatechol), or anisotropic etching using an inductively coupled plasma type dry etcher using CF ₄ gas as an etching gas, for example. I do.

Thereafter, the pad 16, the metal wiring 21 and the bonding layer 22 are formed on the main surface side of the SOI wafer, and subsequently, the silicon nitride film and the silicon on the main surface side of the SOI wafer are formed to form the above-mentioned slits 14. The oxide film is patterned, and the portion of the SOI wafer corresponding to the above-mentioned slit 14 is etched by, for example, TMAH. A large number of semiconductor acceleration sensor bodies 1 are formed on the SOI wafer by etching with a mixed solution of glycol and pure water.

Next, a first glass substrate having a large number of covers 2 formed thereon is bonded to the main surface side of the SOI wafer by anodic bonding. Then, the silicon nitride film and the silicon oxide film on the back surface side of the SOI wafer are removed by etching, and a second glass substrate on which a large number of covers 3 are formed in advance is bonded to the back surface side of the SOI wafer by anodic bonding. When the first glass substrate is anodically bonded, a DC voltage of about 500 V to 800 V is applied at 400 ° C. in vacuum, but both ends of the cover 2 in the left-right direction in FIG. 19 are open. Therefore, the thermal stress strain generated during anodic bonding can be relaxed.

After that, by performing dicing,
A semiconductor acceleration sensor including the semiconductor acceleration sensor body 1 and the pair of covers 2 and 3 as shown in FIG. 19 is obtained.

By the way, the semiconductor acceleration sensor shown in FIG. 19 is mounted on the printed circuit board 40. Here, in the semiconductor acceleration sensor, after the cover 3 on the back surface side of the semiconductor acceleration sensor body 1 is fixed to the printed board 40 via the adhesive layer 50 made of an adhesive material, the pad 16 of the semiconductor acceleration sensor body 1 and the printed board 40. Is connected to the conductive pattern 41 via a bonding wire W made of a gold thin wire or an Al-Si thin wire, and the bonding wire W is protected by being sealed by a protective layer 42 made of, for example, a silicone resin.

The semiconductor acceleration sensor body 1 described above is formed by using an SOI wafer, but not limited to the SOI wafer, one formed by using a silicon wafer is also known.

[0017]

As one means for improving the sensitivity in the semiconductor acceleration sensor having the above-mentioned conventional structure, the bending portion 1 is configured so that the bending amount of the bending portion 13 becomes large.
It is considered that the thickness of 3 is further reduced. However, when the sensitivity is improved by such means, after the semiconductor acceleration sensor is fixed to the printed board 40, the pad 16 and the conductor pattern 41 of the printed board 40 are fixed.
In the bonding process of connecting the and the bonding wire W, if the bonding wire W is a gold wire, ultrasonic vibration is applied while applying a predetermined pressure to the capillary and the bonding is performed at a temperature of about 150 ° C. (substrate temperature). In general, the wire bonding is performed by the sonic thermocompression bonding method, and if the bonding wire W is an Al-Si thin wire, the wire bonding is performed by the ultrasonic method.
There is a risk that the flexible portion 13 will be easily damaged due to cracks in the product, resulting in a significant decrease in yield. For example, when performing wire bonding by ultrasonic thermocompression bonding,
The weight portion 12 may violently swing up and down, left and right due to shock and vibration from the capillary, and the thin flexible portion 13 may be cracked and damaged.

Further, even if the wire bonding succeeds without damaging the bending portion 13, the bonding wire W, the connection portion between the bonding wire W and the conductor pattern 41, and the connection portion between the bonding wire W and the pad 16 are protected. When the protective layer 42 is formed of a sealing resin made of gel such as a silicone resin, the gap between the semiconductor acceleration sensor body 1 and the cover 2 (frame 11
The sealing resin may intrude into the position of the flexible portion 13 from the gap between the insulating layer 18 on the a ′ and the cover 2), and defective sensitivity characteristics may occur due to defective operation of the flexible portion 13. There is.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a semiconductor acceleration sensor capable of preventing defective products from being generated during wire bonding or sealing of bonding wires. To do.

[0020]

In order to achieve the above-mentioned object, the invention of claim 1 has a rectangular frame-shaped frame portion and a bending portion thinner than the frame portion inside the frame portion via a flexible portion. A semiconductor acceleration sensor body having a cantilevered weight portion, and a gauge resistance for detecting strain generated in the bending portion due to displacement of the weight portion with respect to the frame portion, and a main surface side of the semiconductor acceleration sensor body The semiconductor acceleration sensor main body is provided with a first cover that is fixedly attached to the first acceleration control unit and regulates the movement amount of the weight portion, and a second cover that is fixed to the back surface side of the semiconductor acceleration sensor main body that regulates the movement amount of the weight portion. The pad connected to the resistor via the wiring is formed on the main surface side of the free end side portion of the weight portion in the frame portion, and the pad is connected to the gauge resistor. Since the pad connected via the pad is formed on the main surface side of the free end side part of the weight part in the frame part, the stress applied to the bending part due to the impact at the time of wire bonding to the pad is weakened as compared with the conventional case. Therefore, it is possible to prevent the bending portion from being damaged even when the sensitivity is improved by making the bending portion thinner than in the conventional case, and moreover, the bonding wire and the bonding wire and the pad after the wire bonding can be prevented. Since it is possible to prevent the sealing resin from reaching the flexible portion when the connection portion and the like are sealed with the sealing resin, it is possible to eliminate malfunction of the flexible portion due to the sealing resin. Therefore, it becomes possible to prevent defective products from occurring during wire bonding or sealing of the bonding wires.
Since the yield is high, the cost can be reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, A portion formed in a rectangular frame shape with a pair of side frames that connect the left end portions and the right end portions of the support frame and the pad frame on the left and right sides of the weight portion, respectively, and that is formed on at least each side frame of the wiring. Is a diffusion layer wiring, and the semiconductor acceleration sensor body has a bonding layer formed between the first cover and the main surface of each side frame at a portion overlapping with the wiring. The width of each side frame on both the left and right sides of the weight portion can be made narrower than that in the case where the wiring is formed so as not to overlap a portion of the wiring formed on each side frame. Since it is possible to reduce the size of the rate sensor body, as a result, it is possible to reduce the size of the semiconductor acceleration sensor.

According to a third aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on the left and right sides of the weight section, and a pair of side frames that connect the left end sections and the right end sections of the pad frame, respectively. Since the recess is formed in the pad, the vibration energy generated at the time of wire bonding to the pad is attenuated at the recess, so that the impact applied to the bending portion at the time of wire bonding can be further weakened.

In the invention of claim 4, in the invention of claim 3, since the recess is formed in the vicinity of the support frame in the longitudinal direction of each of the side frames, it occurs at the time of wire bonding to the pad. The vibration energy can be rapidly attenuated at a position relatively close to the bending portion.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on the left and right sides of the weight part, and a pair of side frames that respectively connect the left end parts and the right end parts of the pad frame, and each side frame of the semiconductor acceleration sensor body is a support frame. Since it is formed in a planar shape that is longer than the linear distance between the pad frame and each pad frame, the distance until the vibration energy generated at the time of wire bonding to the pad reaches the bending portion is linear for each side frame. Since it can be made longer than in the case where the wire bond is formed, the vibration energy is further attenuated by the time it reaches the flexible portion. The shock applied to the flexible portion more can be weakened even when Ingu.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on a left side and a right side of the weight section, and a pair of side frames connecting the left end sections and the right end sections of the pad frame, respectively. Since the groove is formed on the surface, the surface wave due to the vibration energy generated at the time of wire bonding to the pad can be attenuated by the groove, and the impact applied to the bending portion at the time of wire bonding can be further weakened.

According to a seventh aspect of the invention, in the invention of the sixth aspect, the number of the grooves formed on the main surface of each of the side frames is plural, and the main surface of each of the side frames has the above-mentioned groove. Since the grooves are formed apart from each other along the longitudinal direction of each of the side frames, surface waves due to vibration energy generated at the time of wire bonding to the pad can be further attenuated, and the flexible portion at the time of wire bonding. The impact on the can be further reduced.

According to an eighth aspect of the present invention, in the first aspect of the present invention, the frame portion has a support frame that cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The left and right sides of the weight portion are formed in a rectangular frame shape with a pair of side frames that connect the left end portions and the right end portions of the support frame and the pad frame, respectively, and form a rectangular frame shape. Since at least one of the recesses is formed in a portion overlapping with each of the side frames, vibration energy generated at the time of wire bonding to the pad is attenuated at the recess, so that the bending portion is applied at the time of wire bonding. The shock can be further weakened.

According to a ninth aspect of the present invention, in the eighth aspect of the invention, the number of the recesses formed on the surface facing each of the side frames is plural, and each of the side frames has a corresponding number. Since the recesses are formed apart from each other along the longitudinal direction of each of the side frames, it is possible to further reduce the vibration energy generated at the time of wire bonding to the pad, and the bending portion at the time of wire bonding. The impact on the can be further reduced.

According to a tenth aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on a left side and a right side of the pad frame, and a pair of side frames connecting the right end portions of the support frame and the pad frame, respectively. Since the pad is formed on the main surface side in the central portion, it is possible to reduce the vibration energy generated during wire bonding as compared with the case where the pad is formed at the left end portion or the right end portion of the pad frame.

According to an eleventh aspect of the present invention, in the first aspect of the present invention, the frame portion has a support frame that cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The left and right sides of the weight portion are formed in a rectangular frame shape with a pair of side frames connecting the left end portions and the right end portions of the support frame and the pad frame, and the pad is formed on the main surface of the pad frame. Since the groove surrounding the region is formed, the surface wave due to the vibration energy generated at the time of wire bonding to the pad can be attenuated by the groove, and the impact applied to the bending portion at the time of wire bonding can be further weakened. it can.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) As shown in FIG. 2, a semiconductor acceleration sensor according to a first embodiment includes an SOI substrate 100 having a buried insulating layer 102 made of a silicon oxide film at an intermediate portion in the thickness direction. It has a structure in which glass covers 2 and 3 are laminated on both sides in the thickness direction of the semiconductor acceleration sensor body 1 formed by using. The SOI substrate 100 includes a buried insulating layer 10 between a support layer 101 made of a silicon layer (silicon substrate) and an active layer 103 made of an n-type silicon layer.
2 is formed by a part of the formed SOI wafer.

As shown in FIGS. 1 and 2, the semiconductor acceleration sensor body 1 has a rectangular frame-shaped frame portion 11,
A rectangular weight portion 12 is arranged inside the frame portion 11, and one side around the weight portion 12 is located on the frame portion 11.
It has a structure in which it is continuously and integrally connected to the frame portion 11 via a flexible portion 13 having a smaller thickness. Therefore, a slit 14 is formed around the weight portion 12 with the frame portion 11 except for the bending portion 13. In addition, the bending portion 1
3 are formed in two places separated in the direction along one side of the weight portion 12. Each of the bending portions 13 is provided with two gage resistors 15 as strain detecting elements for detecting the strain generated in the bending portion 13 due to the displacement of the weight portion 12 with respect to the frame portion 11. The gauge resistor 15 is a piezoresistor and is connected by a diffusion layer wiring 17 so as to form a bridge circuit. The pad 16 which will be each terminal of the bridge circuit will be described later.

Therefore, when an external force (that is, acceleration) including a component in the thickness direction of the semiconductor acceleration sensor body 1 acts, the inertia of the weight portion 12 causes the frame portion 11 and the weight portion 12 to move in the thickness direction of the semiconductor acceleration sensor body 1. Is relatively displaced, and as a result, the bending portion 13 bends and the resistance value of the gauge resistor 15 changes. That is, the acceleration acting on the semiconductor acceleration sensor body 1 can be detected by detecting the change in the resistance value of the gauge resistor 15. In this semiconductor acceleration sensor body 1, a weight portion 12 is cantilevered by a frame portion 11 via a bending portion 13 as a cantilever.

A glass cover 2 is bonded (fixed) to the main surface side (upper surface side in FIG. 2) of the semiconductor acceleration sensor body 1 and the back surface side (FIG. 2) in the semiconductor acceleration sensor body 1.
The glass cover 3 is joined (fixed) to the lower surface side of the. The space formed between the cover 2 and the cover 3 is not hermetically sealed, but when the weight portion 12 moves relative to the frame portion 11, a braking force by air against the weight portion 12 (so-called). When the air dump) acts and excessive acceleration (acceleration of several thousand G, for example) is applied, the amount of movement of the weight portion 12 is regulated to prevent the bending portion 13 from being broken. Recesses 2a and 3a for securing a moving range of the weight portion 12 are formed on the surfaces of the covers 2 and 3 facing the weight portion 12, respectively. In addition, the recess 2 in both covers 2 and 3
Protrusion-shaped stoppers 2b and 3b for restricting the movement amount of the weight portion 12 are integrally formed on the inner bottom surfaces of a and 3a, respectively, and the weight portion 12 when acceleration acts on the weight portion 12 is formed.
The bending amount of the flexible portion 13 is prevented by regulating the movement amount of the stoppers 2b and 3b. In this embodiment, the cover 2 constitutes the first cover and the cover 3 constitutes the second cover.
Constitutes the cover of.

By the way, the semiconductor acceleration sensor body 1 is
An insulating layer 18 is formed on the main surface of the active layer 103 (the insulating layer 18 is not shown in FIG. 1),
The above-mentioned pad 16 is connected to the diffusion layer wiring 17 via the metal wiring 21 made of Ai-Si partially embedded in the contact hole formed in the insulating layer 18 and the contact portion 23 between the metal wiring 21 and the diffusion layer wiring 17. It is connected. That is, the pad 16 and the gauge resistor 15 are connected to the diffusion layer wiring 1
7 and the metal wiring 21 are electrically connected. Further, in the semiconductor acceleration sensor body 1, Al is formed on the insulating layer 18 and on the portions of the frame portion 11 that overlap the portions parallel to the extension direction of the bending portion 13.
A bonding layer 22 made of -Si is formed. The insulating layer 18 is composed of a silicon oxide film on the main surface of the active layer 103 and a silicon nitride film formed on the silicon oxide film.

The peripheral portion of the cover 3 on the back surface of the semiconductor acceleration sensor body 1 is joined to the back surface of the semiconductor acceleration sensor body 1 by anodic bonding. On the other hand, the cover 2 on the main surface side of the semiconductor acceleration sensor body 1 is the semiconductor acceleration sensor body 1
Of the frame portion 11 is anodically bonded to the main surface side of the semiconductor acceleration sensor main body 1 through the bonding layers 22 formed on the surface sides of the portions parallel to the extension direction of the bending portion 13, and in the extension direction of the bending portion 13. A gap is formed between the orthogonal portions. That is, if the vertical direction of FIG. 1 is defined as the left-right direction, the frame portion 11 can frame the weight portion 12 in a cantilevered manner (hereinafter referred to as a support frame) 1
1a and a plurality of pads 16 parallel to the support frame 11a
A frame formed with (hereinafter referred to as a pad frame)
11b and the support frame 11a on both the left and right sides of the weight portion 12.
And a pair of side frames 11c and 11d that connect the left end portions of the pad frame 11b and the right end portions of the pad frame 11b, respectively, are formed in a rectangular frame shape, and the insulating layer 18 and the cover 2 on both the frames 11a and 11b are formed. A gap is formed between them. Here, a part of the wiring (a part of the diffusion layer wiring 17) that electrically connects the pad 16 and the gauge resistor 15 is formed on each of the side frames 11c and 11d.

The manufacturing method of the semiconductor acceleration sensor of this embodiment is basically the same as the manufacturing method described in the conventional example, and therefore the description thereof is omitted.

By the way, the semiconductor acceleration sensor of this embodiment is mounted on a printed circuit board 40 as shown in FIG. Here, in the semiconductor acceleration sensor, the cover 3 on the back surface side of the semiconductor acceleration sensor body 1 is attached to the printed circuit board 4
0 through the adhesive layer 50 made of an adhesive material, and then the pad 16 of the semiconductor acceleration sensor body 1 and the printed circuit board 4
The conductive pattern 41 of 0 is connected via a bonding wire W made of a gold thin wire or an Al-Si thin wire, and the bonding wire W is protected by a protective layer 42 made of a silicone resin.

In the semiconductor acceleration sensor of the present embodiment described above, the pad frame 16 connected to the gauge resistor 15 via the wiring as described above is parallel to the support frame 11a supporting the weight portion 12 in a cantilever manner. It is characterized in that it is formed in 11b. That is, the pad 16 connected to the gauge resistor 15 through the wiring is located on the free end side of the weight portion 12 in the frame portion 11 (the weight portion 12 in FIG. 1).
Since it is formed on the main surface side of the pad frame 11b, which is the right end side of the pad frame 11b, the distance between the pad 16 and the bending portion 13 is sufficiently large as compared with the conventional configuration shown in FIGS. Since the slit 14 on the free end side of the weight portion 12 exists on the straight line connecting the pad frame 11b and the bending portion 13, the vibration energy generated at the time of wire bonding to the pad 16 is Attenuated by the slit 14 and side frames 11c, 11
By being transmitted through d, it is attenuated and transmitted to the bending portion 13, and the stress applied to the bending portion 13 due to the impact at the time of wire bonding to the pad 16 can be weakened as compared with the conventional configuration. Therefore, it is possible to prevent the bending portion 13 from being damaged even if the sensitivity is improved by making the bending portion 13 thinner than the conventional configuration.

Moreover, after the wire bonding, the bonding wire W and the bonding wire W and the pad 1 are formed.
Since the sealing resin can be prevented from reaching the bending portion 13 when the connection portion with 6 is sealed by the sealing resin forming the protective layer 42, the malfunction of the bending portion 13 due to the sealing resin can be eliminated. You can Therefore, it is possible to prevent defective products from being generated during wire bonding or sealing of the bonding wires W, and the yield is increased, so that the cost can be reduced.

(Embodiment 2) The basic structure of the semiconductor acceleration sensor of the present embodiment is substantially the same as that of the first embodiment.
As shown in FIG. 5, wiring is provided on the main surface side of each side frame 11c, 11d in the frame portion 11 of the semiconductor acceleration sensor body 1 (the portion of the wiring formed in each side frame 11c, 11d is the diffusion layer wiring 17). The difference is that the bonding layer 22 is formed in each of the overlapping portions, and the width of each of the side frames 11c and 11d is narrower than that in the first embodiment. In short, in the semiconductor acceleration sensor body 1 according to this embodiment, the portions of the wiring that electrically connects the gauge resistor 15 and the pad 16 to the side frames 11c and 11d are formed below the bonding layer 22. Has been done. Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, since the bonding layer 22 is formed on the main surface side of each of the side frames 11c and 11d of the semiconductor acceleration sensor main body 1 at a portion overlapping the wiring, the bonding layer 22 is formed in the first embodiment. Similarly to the case where the wiring is formed so as not to overlap the portions formed on the side frames 11c and 11d, the width of the side frames 11c and 11d on both the left and right sides of the weight portion 12 is reduced. Therefore, the semiconductor acceleration sensor body 1 can be downsized (chip size can be reduced), and as a result, the semiconductor acceleration sensor can be downsized.

(Embodiment 3) The basic structure of the semiconductor acceleration sensor of the present embodiment is substantially the same as that of the first embodiment.
As shown in FIG. 5 and FIG. 5, recesses 24, 24 are formed on the back surface of each of the side frames 11c, 11d in the frame portion 11 of the semiconductor acceleration sensor body 1. Here, in the example shown in FIGS. 4 and 5, the recesses 24, 24 are formed on both left and right sides of the free end of the weight portion 12, respectively. That is, the recesses 24, 24 are formed in the pad frame 1 in the longitudinal direction of the side frames 11c, 11d.
It is formed near 1b. Each recess 24, 24 is SO
K from the back surface side of the I wafer until reaching the embedded insulating layer 102
Anisotropic etching may be performed using an alkaline solution such as OH or TMAH, and the exposed embedded insulating layer 102 may be formed by wet etching or dry etching. Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the present embodiment, however, the recesses 24, 24 are formed on the back surfaces of the side frames 11c, 11d of the semiconductor acceleration sensor body 1, so that the pad 1
Since the vibration energy generated at the time of wire bonding to 6 is attenuated by the recesses 24, 24, the impact applied to the bending portion 13 at the time of wire bonding can be further weakened as compared with the first embodiment.

(Embodiment 4) The basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of the third embodiment.
As shown in FIG. 7 and FIG. 7, the recesses 24, 24 formed on the back surfaces of the side frames 11c, 11d are located on the sides of the two bending portions 13 connecting the weight portion 12 and the support frame 11a. The difference is that it is formed. That is, in the present embodiment, the recesses 24, 24 have the respective side frames 11c, 11d.
In the longitudinal direction (left and right direction in FIG. 6) of the support frame 1
It is formed near 1a. Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

Therefore, in this embodiment, similarly to the third embodiment, each side frame 11 in the semiconductor acceleration sensor body 1 is.
Since the recesses 24 and 24 are formed on the back surfaces of the c and 11d, respectively, the vibration energy generated at the time of wire bonding to the pad 16 is attenuated at the recesses 24 and 24, so that the bending portion 13 is applied at the time of wire bonding. The impact can be further weakened as compared with the first embodiment. Moreover, since the recesses 24, 24 are formed in the vicinity of the support frame 11a in the longitudinal direction of the side frames 11c, 11d, the vibration energy generated at the time of wire bonding to the pad 16 is relatively close to the bending portion 13. It can be rapidly attenuated.

(Fifth Embodiment) The semiconductor acceleration sensor according to the present embodiment has substantially the same basic configuration as that of the first embodiment.
As shown in, the width direction of each of the side frames 11c and 11d on the inner surface (the surface that faces the weight portion 12) and the outer surface (the surface that does not face the weight portion 12) of each of the side frames 11c and 11d ( The difference is that the recessed portion 25 is formed so that a plurality of portions whose vertical dimension in FIG. 8) becomes about half are formed. Here, in each of the side frames 11c and 11d, the formation position of the recess 25 in the extension direction of the flexible portion 13 (the left-right direction in FIG. 8) is shifted between the inner side surface and the outer side surface, and the inner side surface and the outer side surface are alternately arranged. Has been formed. Therefore, each side frame 11c,
As shown in FIG. 8, 11d has a wavy planar shape, and a path connecting the support frame 11a and the pad frame 11b has a support frame 11a and the pad frame 11b.
It is longer than the straight line distance from b. That is,
The semiconductor acceleration sensor body 1 according to the present embodiment is formed in a planar shape such that each of the side frames 11c and 11d is longer than the linear distance between the support frame 11a and the pad frame 11b. Each recess 25 may be formed by wet etching or dry etching. In addition,
Since other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, each side frame 11
c and 11d are the support frame 11a and the pad frame 11
Since it is formed in a planar shape that is longer than the linear distance between the side frames 11c and 11d, the distance until the vibration energy generated at the time of wire bonding to the pad 16 reaches the bending portion 13 is set. Can be made longer than in the case of being formed in a straight line, and the vibration energy is further attenuated by the time it reaches the flexible portion 13. Therefore, the impact applied to the flexible portion 13 during wire bonding is further enhanced. Can be weakened.

(Embodiment 6) The basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of the first embodiment.
And as shown in FIG. 10, the semiconductor acceleration sensor body 1
The difference is that the groove 26 is formed on the main surface of each of the side frames 11c and 11d in the frame portion 11. Here, the groove 26 is formed over the entire length of each side frame 11c, 11d in the width direction and communicates with the slit 14, and the portion of the bonding layer 22 formed on the inner peripheral surface of the groove 26 is the cover 2. Not joined. That is, a gap is formed between the surface of the portion of the bonding layer 22 formed on the inner peripheral surface of the groove 26 and the cover 2. The groove 26 may be formed by wet-etching the planned site of the groove 26 from the main surface of the SOI wafer. Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

Therefore, in this embodiment, each side frame 11c in the frame portion 11 of the semiconductor acceleration sensor body 1 is
Since the groove 26 is formed on the main surface of each 11d, the surface wave due to the vibration energy generated at the time of wire bonding to the pad 16 can be attenuated by the groove 26, and the impact applied to the bending portion 13 at the time of wire bonding can be further reduced. Can be further weakened. In addition, in the present embodiment, the groove 26 is formed over the entire length in the width direction of each of the side frames 11c and 11d, but it is not necessarily required to be formed over the entire length.

(Embodiment 7) The basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of the sixth embodiment.
As shown in FIG. 1 and FIG. 12, the number of the grooves 26 formed on the main surface of each of the side frames 11c and 11d is plural, and the groove 26 is formed on the main surface of each of the side frames 11c and 11d.
Are different from each other in that they are formed separately along the longitudinal direction of each of the side frames 11c and 1d (the left-right direction in FIG. 11).
Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, the surface wave due to the vibration energy generated at the time of wire bonding to the pad 16 can be further attenuated as compared with the semiconductor acceleration sensor of the sixth embodiment, and the bending portion 13 at the time of wire bonding. The impact on the can be further reduced.

(Embodiment 8) The basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of the first embodiment.
As shown in FIG. 3 and FIG. 14, in each of the covers 2 and 3, the recesses 27 and 2 are formed in the portions of the frame portion 11 of the semiconductor acceleration sensor body 1 that overlap the side frames 11c and 11d, respectively.
The difference is that 8 is formed. That is, the cover 2 fixed to the main surface side of the semiconductor acceleration sensor main body 1 is formed with the recesses 27, 27 on both left and right sides of the recess 2a that secures the movement range of the weight portion 12, and the semiconductor acceleration sensor main body. A gap is formed between the bonding layer 22 and the cover 2 at the portions of the two bonding layers 22 formed on the main surface side of 1 that overlap the recesses 27, 27, respectively. Further, the cover 3 fixed to the back surface side of the semiconductor acceleration sensor main body 1 is formed with recesses 28, 28 on both left and right sides of the recess 3a that secures the movement range of the weight portion 12, and the semiconductor acceleration sensor main body 1 A gap is formed between the semiconductor acceleration sensor main body 1 and the cover 3 at the portions of the back surface surrounding the recesses 28, 28, respectively. Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, each cover 2,
3, the frame portion 1 of the semiconductor acceleration sensor body 1
Since the recesses 27 and 28 are formed in the portions overlapping with the respective side frames 11c and 11d of 1, the vibration energy generated at the time of wire bonding to the pad 16 is generated by the recesses 27 and 28.
Since it is attenuated by 28, the impact applied to the bending portion 13 during wire bonding can be further weakened as compared with the semiconductor acceleration sensor of the first embodiment.

In this embodiment, the recesses 27 and 28 are formed in the respective covers 2 and 3 at the portions overlapping the respective side frames 11c and 11d, but at least one of the covers 2 and 3 is formed. If the recesses 27 and 28 are formed, the impact applied to the bending portion 13 during wire bonding can be weakened as compared with the semiconductor acceleration sensor of the first embodiment. However, the recesses 27,
By forming 28, the impact applied to the bending portion 13 can be further weakened.

(Embodiment 9) The semiconductor acceleration sensor of this embodiment has the same basic structure as that of Embodiment 8, and
As shown in FIG. 5 and FIG. 16, the number of the recesses 27 and 28 formed on the surfaces of the covers 2 and 3 facing the side frames 11c and 11d is plural, and
The recesses 27 and 28 are provided on the side frames 11 corresponding to 1d.
The difference is that they are formed separately along the longitudinal direction of c and 11d (left and right direction in FIG. 15). Since the other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, the vibration energy generated at the time of wire bonding to the pad 16 can be further attenuated as compared with the semiconductor acceleration sensor of the eighth embodiment, and the bending portion 13 is affected at the time of wire bonding. The shock can be further weakened.

In the present embodiment as well, similar to the eighth embodiment, the side frames 11c and 11d of the covers 2 and 3 are provided.
Although the recesses 27 and 28 are formed in the portions overlapping with, respectively, the recess 2 is formed in at least one of the covers 2 and 3.
If 7, 28 are formed, the impact applied to the bending portion 13 during wire bonding can be weakened as compared with the semiconductor acceleration sensor of the first embodiment.

(Embodiment 10) By the way, as described in Embodiment 1, a plurality of pads 16 are formed on the main surface side of the pad frame 11b, but the semiconductor acceleration sensor is attached to the printed board 40 or the like by the adhesive layer 50. When bonded through the printed circuit board 4 at the four corners of the semiconductor acceleration sensor.
Since the adhesive force with 0 is weaker than other portions, it is easy to vibrate. If the pads 16 are formed at the portions corresponding to the four corners of the semiconductor acceleration sensor, the vibration energy generated during wire bonding is large. Become.

On the other hand, the basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of the first embodiment, and the structure shown in FIG.
As shown in FIG. 7, the gap between the pads 16 is made smaller than that of the first embodiment so that the pad 1 is provided on the main surface side in the central portion of the pad frame 11b in the horizontal direction (vertical direction in FIG. 17).
The difference is that 6 are collected and formed. Since the other configurations and operations are the same as those of the first embodiment, the first embodiment will be described.
The same components as those of the above are denoted by the same reference numerals and the description thereof will be omitted.

In this embodiment, however, the pads 16 are gathered and formed on the main surface side of the central portion of the pad frame 11b in the left-right direction.
The vibration energy generated during wire bonding can be reduced as compared with the case where the pads 16 are formed at the left end (upper end in FIG. 17) and the right end (lower end in FIG. 17) of FIG.

(Embodiment 11) The basic structure of the semiconductor acceleration sensor of this embodiment is substantially the same as that of Embodiment 1, and as shown in FIG. 18, the pad frame 11b of the frame portion 11 of the semiconductor acceleration sensor body 1 is formed. A groove 29 surrounding the area where all (plural) pads 16 are formed on the main surface.
Are different from each other. The planar shape of the groove 29 is formed in a U shape with the right side open in FIG. 18, and the depth of the groove 29 may be set in the range of several μm to several tens of μm, for example. Here, the groove 29 is, for example, TMA.
The active layer 103 in the SOI wafer may be anisotropically etched from the main surface using an alkaline solution such as H, and the above-described wiring (diffusion layer wiring 17 and metal wiring 21) may be formed after forming the groove 29. It may be formed by. In addition,
Since other configurations and operations are the same as those of the first embodiment, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

Therefore, in the present embodiment, the groove 29 surrounding the region where all (plural) pads 16 are formed is formed on the main surface of the pad frame 11b in the frame portion 11 of the semiconductor acceleration sensor body 1. So pad 1
Surface waves due to vibration energy generated at the time of wire bonding to 6 can be attenuated by the groove 29, and the impact applied to the bending portion 13 at the time of wire bonding can be further weakened as compared with the semiconductor acceleration sensor of the first embodiment.

In each of the above embodiments, the semiconductor acceleration sensor body 1 is formed on the SOI wafer.
The semiconductor acceleration sensor body may be formed not only on the wafer but also on a silicon wafer. Although Pyrex (registered trademark) is used as the covers 2 and 3 in each of the above-described embodiments, any material that can be bonded to the semiconductor acceleration sensor body 1 by anodic bonding or eutectic bonding may be used.

[0065]

According to the invention of claim 1, a frame portion having a rectangular frame shape and a weight portion which is cantilevered inside the frame portion and cantilevered through a flexible portion thinner than the frame portion are formed, A gauge resistor for detecting strain generated in the flexure due to the displacement of the weight with respect to the flexure, and a semiconductor acceleration sensor body formed in the flexure, and fixed to the main surface side of the semiconductor acceleration sensor body to restrict the movement amount of the weight. 1
And a second cover that is fixed to the back surface of the semiconductor acceleration sensor body and regulates the amount of movement of the weight portion. The semiconductor acceleration sensor body has a pad connected to the gauge resistor via wiring. Is formed on the main surface side of the free end side part of the weight part in the main surface side of the part of the frame part on the free end side of the weight part. Since it is formed, the stress applied to the flexible portion due to the impact during wire bonding to the pad can be weakened as compared with the conventional one, so that the sensitivity can be improved by making the flexible portion thinner than the conventional one. It is possible to prevent the flexible portion from being damaged, and yet, after wire bonding, seal the bonding wire and the connecting portion between the bonding wire and the pad. There is an effect that it is possible to eliminate the malfunction of the bending portion by the sealing resin because it is possible to prevent the sealing resin to reach the deflection unit when more sealing. Therefore, it is possible to prevent defective products from being generated at the time of wire bonding or sealing of the bonding wire, and the yield is increased, so that the cost can be reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, the frame portion has a support frame that cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, A portion formed in a rectangular frame shape with a pair of side frames that connect the left end portions and the right end portions of the support frame and the pad frame on the left and right sides of the weight portion, respectively, and that is formed on at least each side frame of the wiring. Is a diffusion layer wiring, and the semiconductor acceleration sensor body has a bonding layer formed between the first cover and the main surface of each side frame at a portion overlapping with the wiring. The width of each side frame on both the left and right sides of the weight portion can be made narrower than that in the case where the wiring is formed so as not to overlap a portion of the wiring formed on each side frame. Since it is possible to reduce the size of the rate sensor body, resulting in an effect that it is possible to reduce the size of the semiconductor acceleration sensor.

According to a third aspect of the present invention, in the first aspect of the present invention, the frame portion cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on the left and right sides of the weight section, and a pair of side frames that connect the left end sections and the right end sections of the pad frame, respectively. Since the recess is formed in the recess, vibration energy generated at the time of wire bonding to the pad is attenuated at the recess, so that there is an effect that it is possible to further reduce the impact applied to the flexible portion at the time of wire bonding. .

In the invention of claim 4, in the invention of claim 3, since the recess is formed in the vicinity of the support frame in the longitudinal direction of each of the side frames, it occurs during wire bonding to the pad. There is an effect that the vibration energy can be rapidly attenuated at a position relatively close to the bending portion.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the frame portion has a support frame that cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on the left and right sides of the weight part, and a pair of side frames that respectively connect the left end parts and the right end parts of the pad frame. Since it is formed in a planar shape that is longer than the linear distance between the pad frame and each pad frame, the distance until the vibration energy generated at the time of wire bonding to the pad reaches the bending portion is linear for each side frame. Since it can be made longer than in the case where the wire bond is formed, the vibration energy is further attenuated by the time it reaches the flexible portion. There is an effect that an impact exerted on the bending portion at the time Ingu more can be weakened even more.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the frame portion cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on a left side and a right side of the weight section, and a pair of side frames connecting the left end sections and the right end sections of the pad frame, respectively. Since the groove is formed on the surface, the surface wave due to the vibration energy generated at the time of wire bonding to the pad can be attenuated by the groove, and the impact applied to the flexible portion at the time of wire bonding can be further weakened. effective.

According to a seventh aspect of the invention, in the invention of the sixth aspect, the number of the grooves formed on the main surface of each of the side frames is plural, and the main surface of each of the side frames has the above-mentioned groove. Since the grooves are formed apart from each other along the longitudinal direction of each of the side frames, surface waves due to vibration energy generated at the time of wire bonding to the pad can be further attenuated, and the flexible portion at the time of wire bonding. This has the effect of further reducing the impact on the.

According to an eighth aspect of the present invention, in the first aspect of the present invention, the frame portion has a support frame that cantilevers the weight portion, a pad frame in which the pad is formed in parallel with the support frame, The left and right sides of the weight portion are formed in a rectangular frame shape with a pair of side frames that connect the left end portions and the right end portions of the support frame and the pad frame, respectively, and form a rectangular frame shape. Since at least one of the recesses is formed in a portion overlapping with each of the side frames, vibration energy generated at the time of wire bonding to the pad is attenuated at the recess, so that the bending portion is applied at the time of wire bonding. The effect is that the shock can be further weakened.

According to a ninth aspect of the invention, in the eighth aspect of the invention, the number of the recesses formed on the surface facing each of the side frames is plural, and the number of the recesses is corresponding to each of the side frames. Since the recesses are formed apart from each other along the longitudinal direction of each of the side frames, it is possible to further reduce the vibration energy generated at the time of wire bonding to the pad, and the bending portion at the time of wire bonding. This has the effect of further reducing the impact on the.

According to a tenth aspect of the present invention, in the first aspect of the present invention, the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, The support frame and the pad frame are formed in a rectangular frame shape on a left side and a right side of the pad frame, and a pair of side frames connecting the right end portions of the support frame and the pad frame, respectively. Since the pad is formed on the main surface side in the central portion, it is possible to reduce the vibration energy generated during wire bonding as compared with the case where the pad is formed at the left end portion or the right end portion of the pad frame. effective.

According to an eleventh aspect of the present invention, in the first aspect of the present invention, the frame portion cantilevers the weight portion, and a pad frame in which the pad is formed in parallel with the support frame. The left and right sides of the weight portion are formed in a rectangular frame shape with a pair of side frames connecting the left end portions and the right end portions of the support frame and the pad frame, and the pad is formed on the main surface of the pad frame. Since the groove surrounding the region is formed, the surface wave due to the vibration energy generated at the time of wire bonding to the pad can be attenuated by the groove, and the impact applied to the bending portion at the time of wire bonding can be further weakened. The effect is that you can do it.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a semiconductor acceleration sensor body according to a first embodiment.

FIG. 2 is a schematic cross-sectional view showing a mounting example of the semiconductor acceleration sensor of the above.

FIG. 3 is a schematic plan view of a semiconductor acceleration sensor body according to the second embodiment.

FIG. 4 is a schematic plan view of a semiconductor acceleration sensor body according to a third embodiment.

FIG. 5 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 6 is a schematic plan view of a semiconductor acceleration sensor body according to the fourth embodiment.

FIG. 7 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 8 is a schematic plan view of a semiconductor acceleration sensor body according to the fifth embodiment.

FIG. 9 is a schematic plan view of a semiconductor acceleration sensor body according to the sixth embodiment.

FIG. 10 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 11 is a schematic plan view of a semiconductor acceleration sensor body according to the seventh embodiment.

FIG. 12 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 13 is a schematic plan view of a semiconductor acceleration sensor body according to the eighth embodiment.

FIG. 14 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 15 is a schematic plan view of a semiconductor acceleration sensor body according to the ninth embodiment.

FIG. 16 is a schematic sectional view of the semiconductor acceleration sensor of the above.

FIG. 17 is a schematic plan view of a semiconductor acceleration sensor body according to the tenth embodiment.

FIG. 18 is a schematic plan view of a semiconductor acceleration sensor body according to the eleventh embodiment.

FIG. 19 is a schematic cross-sectional view in a state where a semiconductor acceleration sensor in a conventional example is mounted.

FIG. 20 is a schematic plan view of the semiconductor acceleration sensor body in the above.

[Explanation of symbols]

1 Semiconductor acceleration sensor body 11 frame part 11a frame (supporting frame) 11b frame (pad frame) 11c side frame 11d side frame 12 Weight 12a recess 13 Flexible part 14 slits 15 gauge resistance 16 pads 17 Diffusion layer wiring 18 Insulation layer 21 Metal wiring 22 Bonding layer 23 Contact part 24 recess 25 recess 26 groove 27 recess 28 recess 29 groove 40 printed circuit board 41 Conductive pattern 42 Protective layer 50 Adhesive layer 100 SOI substrate 101 support layer 102 Embedded insulation layer 103 Active layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hironori Kami             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 4M112 AA02 BA01 CA21 CA24 CA28                       CA33 DA03 DA04 DA12 DA18                       EA03 EA06 EA11 EA13 EA14                       FA07 FA20

Claims (11)

[Claims] 1. A rectangular frame-shaped frame portion and a weight portion which is cantilevered inside the frame portion via a flexible portion having a thinner wall than the frame portion are formed, and the weight portion is displaced with respect to the frame portion. A semiconductor acceleration sensor main body in which a gauge resistance for detecting strain generated in the flexible portion is formed in the flexible portion, a first cover fixed to the main surface side of the semiconductor acceleration sensor main body to restrict the movement amount of the weight portion, and the semiconductor acceleration The semiconductor acceleration sensor body has a second cover fixed to the back surface side of the sensor body to regulate the amount of movement of the weight portion. A semiconductor acceleration sensor, which is formed on the main surface side of the side portion. 2. The frame part includes a support frame that cantilevers the weight part, a pad frame in which the pad is formed in parallel with the support frame, and a support frame and a pad frame on both left and right sides of the weight part. Is formed into a rectangular frame shape with a pair of side frames that connect the left end portions to each other and the right end portions to each other, and at least the portion formed in each side frame is a diffusion layer wiring, and the semiconductor acceleration sensor body The semiconductor acceleration sensor according to claim 1, wherein a bonding layer interposed between the first cover and the first cover is formed on a portion of each side frame that overlaps the wiring. 3. The frame part includes a support frame that cantilevers the weight part, a pad frame in which the pad is formed parallel to the support frame, and a support frame and a pad frame on both left and right sides of the weight part. Is formed into a rectangular frame shape with a pair of side frames connecting the left end portions of the respective side frames and the right end portions thereof, and the semiconductor acceleration sensor body is characterized in that a recess is formed on the back surface of each side frame. The semiconductor acceleration sensor according to claim 1. 4. The semiconductor acceleration sensor according to claim 3, wherein the recess is formed in the vicinity of the support frame in the longitudinal direction of each of the side frames. 5. A support frame in which the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, and a support frame and a pad frame on both left and right sides of the weight portion. Is formed in a rectangular frame shape with a pair of side frames connecting the left end portions and the right end portions of each other, and the semiconductor acceleration sensor main body is configured such that each side frame is longer than the linear distance between the support frame and the pad frame. The semiconductor acceleration sensor according to claim 1, wherein the semiconductor acceleration sensor is formed in a flat plane shape. 6. The support part, wherein the frame part supports the weight part in a cantilevered manner, a pad frame in which the pad is formed in parallel with the support frame, and a support frame and a pad frame on both left and right sides of the weight part. Is formed into a rectangular frame shape with a pair of side frames connecting the left end portions of the respective side frames and the right end portions thereof, and the semiconductor acceleration sensor body is characterized in that a groove is formed on the main surface of each side frame. The semiconductor acceleration sensor according to claim 1. 7. The number of the grooves formed on the main surface of each of the side frames is plural, and the grooves are formed on the main surface of each of the side frames along the longitudinal direction of each of the side frames. 7. The semiconductor acceleration sensor according to claim 6, wherein the semiconductor acceleration sensor is formed separately. 8. The frame part includes a support frame that cantilevers the weight part, a pad frame in which the pad is formed in parallel with the support frame, and a support frame and a pad frame on both left and right sides of the weight part. Is formed into a rectangular frame shape with a pair of side frames that connect the left end portions of the first cover and the right end portions of the first cover and the second cover, respectively, in a portion that overlaps each of the side frames in at least one of the first cover and the second cover. The semiconductor acceleration sensor according to claim 1, wherein each of them has a recess. 9. The number of the recesses formed on the surface facing each of the side frames is plural, and the recesses are provided in the longitudinal direction of each of the side frames corresponding to each of the side frames. 9. The semiconductor acceleration sensor according to claim 8, wherein the semiconductor acceleration sensor is formed along a distance. 10. The frame part includes a support frame that cantilevers the weight part, a pad frame in which the pad is formed in parallel with the support frame, and a support frame and a pad frame on both left and right sides of the weight part. Is formed in a rectangular frame shape with a pair of side frames connecting the left end portions of the pad frame and the right end portions of the pad frame, and the semiconductor acceleration sensor main body has the pad formed on the main surface side in the central portion in the left-right direction of the pad frame. The semiconductor acceleration sensor according to claim 1, wherein: 11. A support frame in which the frame portion supports the weight portion in a cantilevered manner, a pad frame in which the pad is formed parallel to the support frame, and a support frame and a pad frame on both left and right sides of the weight portion. Is formed in a rectangular frame shape with a pair of side frames connecting the left end portions of the pad frame and the right end portions of the pad frame, and the main surface of the pad frame is formed with a groove surrounding the region where the pad is formed. The semiconductor acceleration sensor according to claim 1, which is characterized in that.