JPH09116172A - Semiconductor pressure sensor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor pressure sensor which is large in applicable pressure and can be manufactured at low cost, and the manufacture of the semiconductor pressure sensor. SOLUTION: A semiconductor substrate 11 is a silicon substrate, and the main surface is crystal face (110). At the rear of the semiconductor substrate 11 is a silicon nitride film or a silicon oxide film made by, for example, chemical vapor growth method, and at the center is made an etching mask 17, which has an octagonal pattern consisting of a straight line parallel with the crystal axes <100>, <110>, and <111> of the semiconductor substrate (silicon substrate) 11. A disphragm part 13 is made at the central area of the semiconductor substrate 11 by performing etching, using KOH of 30wt.% heated to, for example, 70 deg.C as anisotropic wet etchant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor pressure sensor for measuring the pressure of gas or fluid and a method for manufacturing the same.

[0002]

2. Description of the Related Art A piezoresistive effect type semiconductor pressure sensor is
Although the (110) plane and the (100) plane are used as the main surfaces, the former is mainly used when the temperature characteristics are important. As this type of semiconductor pressure sensor, for example, the one disclosed in JP-A-57-68080 is known.

A conventional semiconductor pressure sensor will be described below. 11 (a) is a plan view showing a conventional semiconductor pressure sensor, and FIG. 11 (b) is a sectional view taken along line U-U of FIG. 11 (a). As shown in FIG. 11, the main surface of the semiconductor substrate 101 is a crystal plane (110), and a thin diaphragm portion 103 is formed in the central portion of the semiconductor substrate 101 by anisotropic wet etching. The diaphragm 103 has a pressure-sensitive resistor 105 located at the center thereof.
b and 105d are formed, and pressure sensitive resistors 105a and 105c are formed in the peripheral portion. Pressure-sensitive resistor 105
The electrodes a to 105d are connected by the electrodes 104a to 104h so as to form a bridge circuit.
The semiconductor substrate 101 is fixed to the package via the adhesive surface 106 that is bounded by the adhesive surface boundary region 102. When the pressure P is applied from the back surface of the diaphragm portion 103, the diaphragm portion 103 is distorted, and the pressure sensitive resistor 105 is accordingly deformed.
The resistance values of a to 105d change due to the piezoresistive effect. The pressure-sensitive resistors 105a and 105d and the pressure-sensitive resistor 105b,
Since the resistance changes from that of 105c in different directions due to the application of pressure, an electric signal corresponding to the applied pressure amount can be obtained by configuring the bridge circuit as described above. In addition, as described above, the diaphragm portion 103
Is formed by anisotropic wet etching, the shape and size of the diaphragm portion 103 are highly reproducible, and a highly accurate semiconductor pressure sensor can be obtained. In this conventional semiconductor pressure sensor, the bonding surface boundary region 10
The shape of 2 and the diaphragm portion 103 is a quadrangle.

[0004]

Here, for convenience, the pressure applied to the main surface side of the semiconductor substrate is defined as "positive pressure",
The pressure applied to the back surface side of the semiconductor substrate is referred to as "negative pressure". In the case of positive pressure, the force that presses the semiconductor substrate against the package acts, whereas in the case of negative pressure P, the force that pulls the semiconductor substrate away from the package acts. Particularly in the case of a negative pressure, high adhesive strength between the semiconductor substrate and the package is required. That is, when the force for separating the semiconductor substrate from the package is F1 and the adhesive strength between the semiconductor substrate and the package is F2, the semiconductor substrate is peeled from the package if F1> F2. When the pressure receiving area where the semiconductor substrate receives pressure is S1, F1 = P × S
Expressed as 1. When the adhesive force per unit area of the adhesive material used for adhering the semiconductor substrate and the package is f2 and the adhesive area is S2, F2 = f2 × S2. In order to satisfy the condition of F1 <F2, P × S1
<F2 × S2 may be set. P may increase depending on the pressure to be measured, and f2 has a limit, so
A fundamental countermeasure is to increase the ratio S2 / S1 of S1 to S2. However, when S2 / S1 is increased only by increasing the size of the semiconductor substrate, the cost of the semiconductor pressure sensor is increased. In order to increase S2 / S1 without increasing the size of the semiconductor substrate, the difference between the area in the bonding surface boundary region and the area of the diaphragm portion may be reduced.

However, in the above-mentioned conventional semiconductor pressure sensor, since the main surface of the semiconductor substrate 101 is quadrangular, the bonding surface boundary region 102 is also quadrangular, so S2 /
It cannot be said that the area of the semiconductor substrate is effectively utilized to increase S1.

In order to solve the above-mentioned problems in the prior art, the present invention provides a semiconductor pressure sensor which has a large applied allowable pressure, can be manufactured at low cost and easily, and a method of manufacturing the semiconductor pressure sensor. With the goal.

[0007]

In order to achieve the above object, a semiconductor pressure sensor according to the present invention has a structure in which a thin portion formed on a main surface of a semiconductor single crystal substrate and an adhesive surface on the outer side of the thin portion. A semiconductor pressure sensor having a bonding surface provided with a boundary region as a boundary, wherein the main surface of the semiconductor single crystal substrate is a crystal surface (110), and the shape of the bonding surface boundary region is at least a crystal axis < It is characterized in that it is a polygon including a straight line parallel to 111>.

Further, in the structure of the semiconductor pressure sensor of the present invention, the shape of the boundary surface of the bonding surface is further defined by the crystal axis <
It is preferably a polygon including a straight line parallel to 110>. In addition, in the structure of the semiconductor pressure sensor of the present invention, the shape of the bonding surface boundary region further has a crystal axis <100>.
It is preferably a polygon including a straight line parallel to.

Further, in the method for manufacturing a semiconductor pressure sensor according to the present invention, the thin portion formed on the main surface of the semiconductor single crystal substrate and the adhesive surface provided outside the thin portion with the adhesive surface boundary region as a boundary. A method for manufacturing a semiconductor pressure sensor, comprising: an etching mask including at least a straight line parallel to a crystal axis <111> on a back surface of the semiconductor single crystal substrate whose main surface is a crystal surface (110). The thin portion is formed by etching.

Further, in the method for manufacturing a semiconductor pressure sensor of the present invention, the etching mask further has a crystal axis <
It is preferable to include a straight line parallel to 110>. In the method for manufacturing a semiconductor pressure sensor of the present invention, it is preferable that the etching mask further includes a straight line parallel to the crystal axis <100>.

In the method for manufacturing a semiconductor pressure sensor of the present invention, it is preferable that the thin portion is formed by anisotropic wet etching.

[0012]

According to the structure of the semiconductor pressure sensor of the present invention, a thin wall portion formed on the main surface of the semiconductor single crystal substrate and a bonding surface boundary region as a boundary are provided outside the thin wall portion. And a bonding surface, the main surface of the semiconductor single crystal substrate is a crystal surface (110), and the shape of the bonding surface boundary region is at least a crystal axis <
By being a polygon containing straight lines parallel to 111>,
Since the area of the bonding surface becomes large, it is possible to realize a semiconductor pressure sensor having a large allowable applied pressure.

In addition, in the structure of the semiconductor pressure sensor of the present invention, the shape of the boundary surface of the bonding surface further has a crystal axis <1.
According to a preferred example of being a polygon including a straight line parallel to 10>, the shape of the bonding surface boundary region is the crystal axis <111>.
Since it is possible to further increase the area of the bonding surface as compared with the case where only the straight line parallel to is included, it is possible to realize a semiconductor pressure sensor with a larger applied allowable pressure.

Further, in the structure of the semiconductor pressure sensor of the present invention, the shape of the boundary area of the bonding surface further has a crystal axis <1.
According to a preferable example of a polygon including a straight line parallel to 00>, the shape of the bonding surface boundary region is the crystal axis <111>.
Since it is possible to further increase the area of the bonding surface as compared with the case where only the straight line parallel to is included, it is possible to realize a semiconductor pressure sensor with a larger applied allowable pressure.

Further, according to the method for manufacturing a semiconductor pressure sensor of the present invention, the thin-walled portion formed on the main surface of the semiconductor single crystal substrate is provided outside the thin-walled portion with the bonding surface boundary region as a boundary. A method of manufacturing a semiconductor pressure sensor having an adhesive surface, wherein at least a crystal axis <111> is provided on a back surface of the semiconductor single crystal substrate whose main surface is a crystal surface (110).
Since the thin portion is formed by etching using an etching mask including a straight line parallel to, it is possible to increase the area of the bonding surface without changing the dimensions of the semiconductor single crystal substrate. A semiconductor pressure sensor having a large allowable pressure can be manufactured at a low price.

In the method for manufacturing a semiconductor pressure sensor of the present invention, the etching mask further has a crystal axis <1.
According to a preferred example of including a straight line parallel to 10>,
Since the area of the bonding surface can be further increased without changing the size of the semiconductor single crystal substrate, a semiconductor pressure sensor with a larger applied allowable pressure can be manufactured at low cost.

In the method for manufacturing a semiconductor pressure sensor of the present invention, the etching mask further has a crystal axis <1.
According to a preferred example of including a straight line parallel to 00>,
Since the area of the bonding surface can be further increased without changing the size of the semiconductor single crystal substrate, a semiconductor pressure sensor with a larger applied allowable pressure can be manufactured at low cost.

Further, in the method for manufacturing a semiconductor pressure sensor of the present invention, according to a preferable example of forming the thin portion by anisotropic wet etching, it is possible to form the highly uniform and highly accurate thin portion. Therefore, it is possible to manufacture a semiconductor pressure sensor having high performance and large applied allowable pressure at a low price.

[0019]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. <First Embodiment> FIG. 1A is a plan view showing a first embodiment of a semiconductor pressure sensor according to the present invention, and FIG.
1A is a cross-sectional view taken along line AA, and FIG.
1B is a sectional view taken along line B, FIG. 1D is a sectional view taken along line CC of FIG. 1A, FIG. 2 is a perspective view of the semiconductor pressure sensor shown in FIG. FIG. 8 is a plan view of an etching mask used when forming the diaphragm portion of the semiconductor pressure sensor shown in FIG.

As shown in FIGS. 1 and 2, the semiconductor substrate 11
Is a silicon substrate, the main surface of which is a crystal plane (110). A thin diaphragm portion 13 is formed in the central portion of the semiconductor substrate 11 by anisotropic wet etching. The diaphragm portion 13 has pressure-sensitive resistors 15b and 15d formed at the center thereof and pressure-sensitive resistors 15a and 15c formed at the peripheral portions thereof. The pressure-sensitive resistors 15a to 15d are connected by electrodes 14a to 14d, respectively, so as to form a bridge circuit. The semiconductor substrate 11 is fixed to the package via the adhesive surface 16 that is bounded by the adhesive surface boundary region 12.

When pressure is applied from the back surface of the diaphragm portion 13, the diaphragm portion 13 is distorted, and the resistance values of the pressure-sensitive resistors 15a to 15d are changed due to the piezoresistive effect. Pressure-sensitive resistors 15a and 15d and pressure-sensitive resistor 15
Since the resistances of b and 15c change in different directions due to the application of pressure, by configuring the bridge circuit as described above, an electric signal corresponding to the applied pressure amount can be obtained.

Here, a method of forming the diaphragm portion will be described. First, a silicon nitride film or a silicon oxide film is formed on the back surface of the semiconductor substrate 11 by, for example, a chemical vapor deposition method, and a semiconductor substrate (silicon substrate) is formed at the central portion as shown in FIG. 3 by a normal photo-etching technique. An etching mask 17 having an octagonal pattern composed of straight lines parallel to 11 crystal axes <100>, <110>, and <111> is formed. Next, etching is performed by using, for example, 30% by weight of KOH heated to 70 ° C. as an anisotropic wet etching solution to form the diaphragm portion 13 in the central portion of the semiconductor substrate 11. Section AA of semiconductor substrate 11 (FIG. 1A) after formation of diaphragm portion 13, B-
The cross section B and the cross section C-C are as shown in FIGS. That is, in the AA cross section, FIG.
As shown in (b), a (100) plane is formed on the etched surface D. In the BB cross section, as shown in FIG. 1C, a (100) plane is formed on the etching surface D and a (111) plane perpendicular to the main surface of the semiconductor substrate 11 is formed on the etching surface E. To be done. In the CC cross section, as shown in FIG. 1D, the (111) plane is formed on the etching surface F.

The silicon substrate has a diamond structure, and (1
Since the 11) plane has a higher atomic density than the (110) plane,
The etching rate of the (111) plane is low. The etching rate for each crystal plane is 0.6 μm / min for the (100) plane,
0.1 μm / min on (110) plane and 0.0 on (111) plane
06 μm / min. That is, the ratio of etching rates on these three surfaces is 100: 16: 1.

As described above, the pattern of the etching mask 17 has a crystal axis <11 of the semiconductor substrate (silicon substrate) 11.
1> includes a straight line parallel to 1>, the crystal plane (11) perpendicular to the main surface of the semiconductor substrate (silicon substrate) 11 during etching.
The etching surface E which is 1) is easily exposed. For this reason, the shape of the diaphragm portion 13 remains a quadrangle, and the dimensions are the same as the conventional one, but the shape of the bonding surface boundary region 12 is an octagon including the crystal axis <111>.
The area of 6 becomes large. When the diaphragm portion 13 is formed by using the etching mask 17 including the straight line parallel to the crystal axis <111> of the semiconductor substrate (silicon substrate) 11 as described above, the size of the semiconductor substrate 11 and the shape and dimension of the diaphragm portion 13 are reduced. Since it is possible to increase only the area of the adhesive surface 16 without changing the semiconductor pressure sensor, a semiconductor pressure sensor with a large applied allowable pressure can be manufactured at low cost.

FIG. 4 (a) is a plan view showing another mode of the first embodiment of the semiconductor pressure sensor according to the present invention, FIG. 4 (b).
4A is a sectional view taken along line GG in FIG. 4A, and FIG.
4 is a cross-sectional view taken along line H-H of FIG. 4, and FIG. 4D is a cross-sectional view taken along line I-I of FIG. In manufacturing the semiconductor pressure sensor shown in FIG. 4A, the crystal axis <100 is used as an etching mask for forming the diaphragm portion 13 as in FIG.
An etching mask having an octagonal pattern, which is composed of straight lines parallel to <>, <110>, and <111>, and has a length longer than that in the case of FIG. 3, is used. Since other configurations are the same as the configurations shown in FIG. 1, the same reference numerals are given to the same portions, and the description thereof will be omitted.

When the diaphragm portion 13 is formed using the above etching mask, the diaphragm portion 13
Of the semiconductor substrate 11 (FIG. 4A) after the formation of
The cross section, the HH cross section, and the I-I cross section are shown in FIGS.
become that way. That is, in the GG cross section, FIG.
Similar to (b), the (100) plane is formed on the etching surface D (FIG. 4B). In the I-I cross section, FIG.
Similar to (d), the (111) plane is formed on the etching surface F (FIG. 4D). On the other hand, in manufacturing the semiconductor pressure sensor shown in FIG.
Since the length of the straight line parallel to is longer than that of the etching mask used for manufacturing the semiconductor pressure sensor of FIG. 3, the HH cross section of FIG. Unlike the case, the etching surface E is (111) perpendicular to the main surface of the semiconductor substrate 11.
Only the surface is formed (FIG. 4 (c)). Therefore, as in the case of FIG. 1, since the adhesive surface boundary region 12 is octagonal and the shape of the diaphragm portion 13 is quadrangular, the pressure-sensitive characteristic does not change. However, in the HH cross section, unlike the case of FIG. 1, only the (111) plane perpendicular to the main surface of the semiconductor substrate 11 is formed on the etching surface E, so that the area of the bonding surface 16 further increases. . As a result, the adhesive strength with the package is further increased, so that it is possible to manufacture a semiconductor pressure sensor with a larger applied allowable pressure at a low cost.

FIG. 5 (a) is a plan view showing still another mode of the first embodiment of the semiconductor pressure sensor according to the present invention, FIG.
5B is a sectional view taken along line JJ of FIG. 5A, and FIG.
FIG. 5A is a sectional view taken along line KK in FIG. 5A, and FIG.
FIG. In manufacturing the semiconductor pressure sensor shown in FIG. 5A, the crystal axis <1 is used as an etching mask used for forming the diaphragm portion 13 as in FIG.
00>, <110>, and <111>, and the length of the straight line parallel to the crystal axis <111> is more than that of the etching mask used for manufacturing the semiconductor pressure sensor of FIG. An etching mask with a long octagonal pattern was used. Since other configurations are the same as the configurations shown in FIGS. 1 and 4, the same reference numerals are given to the same portions, and the description thereof will be omitted.

When the diaphragm portion 13 is formed by using the above etching mask, the diaphragm portion 13 is formed.
Of the semiconductor substrate 11 (FIG. 5A) after forming the
The cross section, the KK cross section, and the LL cross section are shown in FIGS.
become that way. That is, in the JJ cross section, FIG.
Similar to (b), the (100) plane is formed on the etched surface D (FIG. 5B). In the KK cross section, FIG.
Similar to (c), only the (111) plane perpendicular to the main surface of the semiconductor substrate 11 is formed on the etching surface E (FIG. 5).
(C)). In the LL cross section, the (111) plane is formed on the etching surface F as in the case of FIG.
(D)). In this case, in manufacturing the semiconductor pressure sensor shown in FIG. 5A, the length of the straight line parallel to the crystal axis <111> is larger than that of the etching mask used in manufacturing the semiconductor pressure sensor in FIG. Since a longer etching mask is used, the bonding surface boundary area 1
Although 2 is an octagon, the shape of the diaphragm portion 13 is also octagonal and the area of the diaphragm portion 13 is reduced. For this reason, the pressure-sensitive characteristics have low sensitivity, but the area of the adhesive surface 16 increases and the adhesive strength with the package increases. In this way, a semiconductor pressure sensor whose measurement pressure range is higher is manufactured by changing only the etching mask used in the diaphragm etching process on the back surface in the same manufacturing process on the main surface side of the semiconductor substrate 11. can do.

<Second Embodiment> FIG. 6A is a plan view showing a second embodiment of the semiconductor pressure sensor according to the present invention.
6B is a sectional view taken along line MM in FIG. 6A, and FIG.
6A is a sectional view taken along line N-N in FIG. 6D, and FIG.
6 is a perspective view of the semiconductor pressure sensor shown in FIG. 6 (a) viewed from the back side, and FIG. 8 is an etching mask used in forming the diaphragm portion of the semiconductor pressure sensor shown in FIG. 6 (a). FIG. This embodiment is the same as the first embodiment except the pattern of the etching mask used for forming the diaphragm portion 13. For this reason, the first
The same parts as those of the embodiment are given the same reference numerals and the description thereof will be omitted.

In manufacturing the semiconductor pressure sensor shown in FIGS. 6 (a) and 7, the semiconductor substrate (silicon substrate) 11 is formed in the central portion as an etching mask used for forming the diaphragm portion 13 as shown in FIG. Crystal axis of <110
>, And an etching mask 27 having a hexagonal pattern of straight lines parallel to <111> was used. Therefore, the cross section of the semiconductor substrate 11 after the diaphragm portion 13 is formed is as shown in FIGS. That is, O-
In the O cross section, the (111) plane is formed on the etching surface F, as in the case of FIG. 1D of the first embodiment (FIG. 6D). On the other hand, in the MM cross section, FIG.
Unlike the case (1), an etching surface Q higher than the (100) surface is formed (FIG. 6B). Further, in the NN cross section, unlike the case of FIG.
Then, only the (111) plane perpendicular to the main surface of the semiconductor substrate 11 is formed (FIG. 5C). Therefore, although the bonding surface boundary region 12 is hexagonal, the shape of the diaphragm portion 13 is octagonal, and the area of the diaphragm portion 13 is small. For this reason, the pressure-sensitive characteristics have low sensitivity, but the adhesive surface 1
The area of 6 increases and the adhesive strength with the package increases. In this way, a semiconductor pressure sensor whose measurement pressure range is higher is manufactured by changing only the etching mask used in the diaphragm etching process on the back surface in the same manufacturing process on the main surface side of the semiconductor substrate 11. can do.

<Third Embodiment> FIG. 9A is a plan view showing a third embodiment of the semiconductor pressure sensor according to the present invention.
9B is a sectional view taken along line RR in FIG. 9A, and FIG.
9A is a sectional view taken along line S-S, and FIG. 9D is a cross-sectional view taken along line T- of FIG.
FIG. 10 is a sectional view of T, and FIG. 10 is a plan view of an etching mask used when forming the diaphragm portion of the semiconductor pressure sensor shown in FIG. This embodiment is also the same as the first and second embodiments except for the pattern of the etching mask used for forming the diaphragm portion. For this reason, the same parts as those of the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In manufacturing the semiconductor pressure sensor shown in FIG. 9A, as the etching mask used for forming the diaphragm portion 13, as shown in FIG. 10, the crystal axis of the semiconductor substrate (silicon substrate) 11 is formed in the central portion. An etching mask 37 having a rhombic pattern consisting of only straight lines parallel to <111> was used. Therefore, the diaphragm portion 1
Sections of the semiconductor substrate 11 (FIG. 9A) after forming 3 are as shown in FIGS. 9B to 9D. That is, R-
In the R cross section, as in the case of FIG.
An etching surface Q higher than the 0) surface is formed (FIG. 9).
(B)). In the S-S cross section, as in the case of FIG. 6C, only the (111) plane perpendicular to the main surface of the semiconductor substrate 11 is formed on the etching surface E (FIG. 9).
(C)). In the TT cross section, as in the case of FIG. 6D, the (111) plane is formed on the etching surface F (FIG. 9D). However, in this case, when manufacturing the semiconductor pressure sensor shown in FIG. 9A, unlike the case of the second embodiment, a straight line parallel to the crystal axis <110> is not included, and the crystal axis <111> is included. Since the etching mask 37 having a rhombic pattern consisting of only straight lines parallel to is used, the bonding surface boundary region 12 has a rhombic shape, and the diaphragm portion 13 has an octagonal shape. Therefore, the second
Although the area of the adhesive surface 16 is smaller than that in the above embodiment, the area of the diaphragm portion 13 is larger. Therefore,
It is possible to manufacture a pressure sensor having a pressure-sensitive characteristic on the low pressure side as compared with the case of the second embodiment.

As described above, according to the above-mentioned embodiment, since the diaphragm portion 13 is formed by using the anisotropic wet etching technique, the diaphragm portion can be formed with high uniformity and high accuracy. Therefore, a high performance semiconductor pressure sensor can be manufactured. In addition, the bonding surface 16 can be made larger than before without changing the size of the semiconductor substrate 11.
Since it is possible to increase the area, it is possible to manufacture a semiconductor pressure sensor having a large applied allowable pressure at a low cost. That is, according to the above-mentioned embodiment, it is possible to manufacture a high-performance semiconductor pressure sensor having a large applied allowable pressure at a low price.

In the above embodiment, the piezoresistive effect type semiconductor pressure sensor is described as an example.
The present invention can be applied to any detection type semiconductor pressure sensor as long as it is a semiconductor pressure sensor having a semiconductor thin portion such as a diaphragm portion.

In the above embodiment, the silicon substrate is used as the semiconductor single crystal substrate, but the present invention is not limited to this, and a gallium arsenide substrate may be used, for example.

Although KOH is used as the anisotropic wet etching solution in the above embodiment, the anisotropic wet etching solution is not limited to this. For example, hydrazine or an aqueous solution of ethylenediamine / birocatechol may be used.

[0037]

As described above, according to the structure of the semiconductor pressure sensor of the present invention, the area of the bonding surface becomes large, so that the semiconductor pressure sensor with a large applied allowable pressure can be realized.

Further, according to the method of manufacturing a semiconductor pressure sensor of the present invention, the area of the bonding surface can be increased without changing the size of the semiconductor single crystal substrate. It can be manufactured at a low price.

[Brief description of the drawings]

FIG. 1A is a first semiconductor pressure sensor according to the present invention.
Is a plan view showing an embodiment of the present invention, (b) is a sectional view taken along line AA of (a), (c) is a sectional view taken along line BB of (a), and (d) is a sectional view taken along line CC of (a). is there.

FIG. 2 is a perspective view of the semiconductor pressure sensor shown in FIG. 1A as viewed from the back side.

FIG. 3 is a plan view of an etching mask used when forming the diaphragm portion of the semiconductor pressure sensor shown in FIG.

FIG. 4A is a first semiconductor pressure sensor according to the present invention.
2 is a plan view showing another aspect of the embodiment of FIG.
-G sectional view, (c) is an H-H sectional view of (a), and (d) is an I-I sectional view of (a).

FIG. 5A is a first semiconductor pressure sensor according to the present invention.
The top view which shows the other aspect of the Example of (a), (b) is JJ sectional drawing of (a), (c) is KK sectional drawing of (a), (d) is L of (a). It is a -L sectional view.

FIG. 6 (a) is a second semiconductor pressure sensor according to the present invention.
Is a plan view showing an embodiment of the present invention, (b) is an MM sectional view of (a), (c) is an NN sectional view of (a), and (d) is an OO sectional view of (a). is there.

FIG. 7 is a perspective view of the semiconductor pressure sensor shown in FIG. 6A as viewed from the back side.

FIG. 8 is a plan view of an etching mask used when forming the diaphragm portion of the semiconductor pressure sensor shown in FIG.

FIG. 9A is a third semiconductor pressure sensor according to the present invention.
Is a plan view showing an embodiment of the present invention, (b) is an RR sectional view of (a), (c) is an SS sectional view of (a), and (d) is a TT sectional view of (a). is there.

FIG. 10 is a plan view of an etching mask used when forming the diaphragm portion of the semiconductor pressure sensor shown in FIG.

11A is a plan view showing a conventional semiconductor pressure sensor, and FIG. 11B is a sectional view taken along line U-U of FIG.

[Explanation of symbols]

 11 Semiconductor Substrate 12 Adhesive Surface Border Region 13 Diaphragm Part 16 Adhesive Surface 17, 27, 37 Etching Mask D, E, F, Q Etching Surface P Pressure

Claims (7)

[Claims] 1. A semiconductor pressure sensor comprising a thin portion formed on a main surface of a semiconductor single crystal substrate, and an adhesive surface provided outside the thin portion with an adhesive surface boundary region as a boundary. The main surface of the semiconductor single crystal substrate is the crystal plane (110), and the shape of the bonding surface boundary region is at least the crystal axis <
The semiconductor pressure sensor is a polygon including a straight line parallel to 111>. 2. The shape of the bonding surface boundary region further has a crystal axis <
The semiconductor pressure sensor according to claim 1, wherein the semiconductor pressure sensor is a polygon including a straight line parallel to 110>. 3. The shape of the bonding surface boundary region further has a crystal axis <
The semiconductor pressure sensor according to claim 1, which is a polygon including a straight line parallel to 100>. 4. A method for manufacturing a semiconductor pressure sensor, comprising: a thin portion formed on a main surface of a semiconductor single crystal substrate; and an adhesive surface provided outside the thin portion with an adhesive surface boundary region as a boundary. The thin portion is formed on the back surface of the semiconductor single crystal substrate whose main surface is the crystal plane (110) by etching using an etching mask including at least a straight line parallel to the crystal axis <111>. And method for manufacturing a semiconductor pressure sensor. 5. The etching mask further has a crystal axis <11.
The method of manufacturing a semiconductor pressure sensor according to claim 4, including a straight line parallel to 0>. 6. The etching mask further has a crystal axis <10.
The method of manufacturing a semiconductor pressure sensor according to claim 4, including a straight line parallel to 0>. 7. The method for manufacturing a semiconductor pressure sensor according to claim 4, wherein the thin portion is formed by anisotropic wet etching.