JPH0888376A - Manufacture of semiconductor sensor device and semiconductor sensor device - Google Patents

Abstract

PURPOSE: To form a membrane structure without producing steps between a membrane, a semiconductor lead and a thin film detection element, improve the reliability and sensor characteristics and improve the productivity. CONSTITUTION: A process in which a defect layer 33 having a predetermined depth is formed in the main surface of a semiconductor substrate 20, a process in which a membrane 21 which is made of etching-resistant material is formed on the main surface of the semiconductor substrate 20 and a process in which at least one etchant supply inlet which pierces through the membrane 21 and reaches the defect layer 33 is formed in the predetermined region of the membrane 21 are included. Further, a process in which the etchant is supplied through the etchant supply inlet and the defect layer 33 is removed by etching and the semiconductor substrate 20 is subjected to anisotropic etching to form an isolation space is included.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor sensor device such as a temperature sensor, an infrared sensor, a pressure sensor and an acceleration sensor having a membrane structure, and a semiconductor sensor device manufactured by the method.

[0002]

2. Description of the Related Art As a semiconductor sensor device having a membrane structure, one disclosed in, for example, Japanese Patent Application Laid-Open No. 3-94127 is known. This semiconductor sensor device is shown in FIG.
, The membrane 2 is formed on the main surface of the semiconductor substrate 1 made of silicon, the concave portion is formed on the main surface of the semiconductor substrate 1, and the thermal separation space 3 is provided between the membrane 2 and the membrane 2. A sensor element including a diode 4 for temperature detection, semiconductor leads 5 and 6, a protective film 7, an infrared absorption film 8 and the like is provided on the top. A method of manufacturing a semiconductor sensor device of this type is disclosed in, for example, Japanese Patent Laid-Open No. 62-76784.

The thermal isolation space 3 of the semiconductor sensor device shown in FIG. 10 is formed as follows. As shown in FIG. 11A, a polysilicon sacrificial layer 9 having an isotropic etching property is deposited in a predetermined thickness in the isolation space forming region of the main surface of the semiconductor substrate 1. After that, an etching resistant layer to be the membrane 2 is deposited on the polysilicon sacrificial layer 9 to form an etching solution injection port 10. An anisotropic etching solution such as hydrazine, KOH, EDP is injected from the etching solution injection port 10. Since the surface orientation of the polysilicon sacrificial layer 9 is macroscopically random, it exhibits isotropic etching characteristics. Therefore, in the polysilicon sacrificial layer 9, the etching is not stopped at the (111) plane due to the etching with the anisotropic etching liquid, and the entire region of the polysilicon sacrificial layer 9 is etched. Therefore, the separation space 3 having an inverted quadrangular pyramid shape or an inverted quadrangular pyramid trapezoidal shape whose bottom surface is the entire region of the polysilicon sacrificial layer 9 is formed, and the membrane 2 is formed.

Alternatively, the membrane structure can be formed by offsetting the orientation flat surface of the semiconductor substrate 1 or the injection port 10 from the [110] direction of the semiconductor substrate 1.

[0005]

However, the membrane 2, the semiconductor leads 5 and 6 are traversed over the polysilicon sacrificial layer 9.
Is formed, as shown in FIG. 10 and FIG.
As a trace of disappearance of the polysilicon sacrificial layer 9, a step S is formed on the membrane 2 and the semiconductor leads 5 and 6 at a position corresponding to the peripheral edge of the separation space 3. Due to this step S, the reliability of the strength of the membrane 2 is lowered, and the thinning of the membrane 2 is limited. In a temperature sensor or an infrared sensor, there is a limit to the heat separation of the sensor element part, which causes a decrease in detection accuracy. Further, in the pressure sensor and the acceleration sensor, the minimum detectable value becomes large. Further, the step S causes the thin film sensing elements such as the semiconductor leads 5 and 6 and the thermopile to be cut off at the peripheral edge of the separation space, so that there is a limit to the thinning of these and a limit to the improvement of the sensor characteristics.

When the membrane structure is formed by the latter method, a plurality of injection ports 10 are provided and rectangles formed by the intersection lines of the (111) plane formed by etching and the (100) plane formed by the main surface are mutually formed. They must be overlapped, which limits the shape of the membrane 2.

An object of the present invention is to provide a method for manufacturing a semiconductor sensor device which is improved in reliability and sensor characteristics by forming a membrane structure without forming a step on a membrane, a semiconductor lead and a thin film sensing element, and which is excellent in productivity. Another object of the present invention is to provide a semiconductor sensor device manufactured by the method.

[0008]

The present invention will be described with reference to FIGS. 1 to 3 showing an embodiment. The present invention, as shown in FIG. 1, includes a recess 22 formed on the main surface of a semiconductor substrate 20.
And the membrane 21 provided above the recess 22.
And a method for manufacturing a semiconductor sensor device including the sensor element provided on the membrane 21. Then, as shown in FIGS. 2 and 3, the method for manufacturing a semiconductor sensor device according to the present invention forms a defect layer 33 having an etching characteristic in which anisotropy is substantially weakened from a main surface of a semiconductor substrate 20 to a predetermined depth. And a step of forming a membrane 21 made of an etching resistant material on the main surface of the semiconductor substrate 20 (FIG. 2B).
(C)) and a step of forming at least one etching solution inlet 32 penetrating the membrane 21 and reaching the defect layer 33 in a predetermined region of the membrane 21 (FIG. 3).
(D)), an anisotropic etching solution is injected into the etching solution injection port 32 to remove the defect layer 33 and the defect layer 3
The above-described object is achieved by including a step of anisotropically etching the semiconductor substrate 20 from the portion where 3 is removed to form the recess 22 (FIG. 3E). In the method of manufacturing a semiconductor sensor device according to the present invention, the defect layer 33 is formed as a crystal defect layer by a physical treatment such as an ion implantation method or a sandblast method, or is formed as a porous layer by a chemical porosification treatment. be able to. When the ion implantation method is used, silicon ions are implanted into the silicon semiconductor substrate 20. Further, it is necessary that the dose amount in the ion implantation does not exceed the critical dose amount for amorphizing the semiconductor substrate 20. The manufacturing method according to claim 6 is, as shown in FIG. 5, (100) of the semiconductor substrate 20A.
The surface is the main plane, the etching inlet 32A formed in the membrane 21A provided on the main plane is triangular, and the two sides of the triangle are formed at a predetermined angle with the (110) plane. . The semiconductor temperature sensor device according to claim 7 is manufactured by the manufacturing method according to any one of claims 1 to 6, wherein a temperature sensitive element is formed on the membrane 21 and the recess is the heat separation space 22. The semiconductor pressure sensor device according to claim 8 is manufactured by the manufacturing method according to any one of claims 1 to 6, and as shown in FIG.
As C, a strain gauge type bridge circuit is formed on the membrane so that the membrane 21C is bent in accordance with the difference between the reference pressure chamber 22C and the detected pressure, and a signal corresponding to the strain of the membrane 21C is output.

[0009]

The defect layer 33 accelerates the etching rate of (111) of the semiconductor substrate 20, the defect layer 33 acts in the same manner as the polysilicon sacrifice layer in the conventional manufacturing method, and is injected into the etching solution inlet 32. At least the defect layer 3 is formed by etching the semiconductor substrate 20 with the isotropic etching solution.
An inverted quadrangular pyramid shape or an inverted quadrangular pyramid trapezoidal recessed portion 22 having the entire area of 3 as the bottom surface is formed, and a step cannot be formed in the membrane 21 and the sensor element formed on the membrane.

Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for the purpose of making the present invention easy to understand. It is not limited to.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a thermal infrared sensor manufactured by the manufacturing method according to the present invention. This infrared sensor has a silicon nitride (S
iN) is provided with the membrane 21. An inverted quadrangular pyramidal heat separation chamber 22 is formed between the silicon substrate 20 and the membrane 21.

On the membrane 21, four sets of n-type polysilicon layers 23 and p-type polysilicon layers 24, which constitute a thermopile, are formed in a cross shape with a strip pattern. One end of each of the n-type polysilicon layer 23 and the p-type polysilicon layer 24 of each set is formed of aluminum-silicon (A).
The n-type polysilicon layer 23 and the p-type polysilicon layer 24 excluding one set are connected to each other by a hot junction 25 made of Al-Si). ) Are connected to each other by the cold junction 26, and the other end of the remaining pair of n-type polysilicon layer 23 and p-type polysilicon layer 24 has external connection terminals 27, 2 respectively.
8 are connected to form a thermopile as a whole.

The surface of the thermopile is covered with an interlayer insulating film 29 made of phosphorous glass containing boron (BPSG) or the like.
A protective film 30 made of SG) or SiN is laminated. An infrared absorption film 31 made of Au-black (gold black) or the like is formed on the protective film 30 on the heat separation chamber 22 corresponding to the hot junction 25. The membrane 21, the interlayer insulating film 29, and the portion corresponding to the four corners of the heat separation chamber 22,
A square etching solution inlet 32 penetrating the protective film 30.
Are formed. The reference numeral 33a indicates a trace of a defect layer 33 described later. The defect layer 33 is once formed in the manufacturing process, but disappears by etching in a later process.

A method of manufacturing the thermal infrared sensor shown in FIG. 1 will be described with reference to FIGS. 2 (a) to (f) and FIGS. 3 (a) to (f). First, as shown in FIGS. 2 (a) and 2 (b),
The silicon substrate 20 whose main surface is the (100) plane is patterned with a photoresist 34, and Si ⁺ is added to a defect layer formation region by the patterning with an acceleration voltage of 100 Ke.
Ion-implantation with a dose of 1 × 10 ¹⁵ (cm ^-2 ) at V
The defect layer 33 is formed.

Under these conditions, the average range is 147 nm and the standard deviation is 56.7 nm. The critical dose of silicon is about 8 × 10 ¹⁵ (cm ^-2 ) when the substrate temperature is 100 ℃.
Therefore, continuous amorphous silicon is not formed on the silicon substrate 20, and a large number of crystal defects are formed while maintaining a macroscopic crystalline state. In such a state, as compared with the case where amorphous silicon is continuously formed by ion implantation exceeding the critical dose amount, recovery of crystallinity is difficult to proceed even by the subsequent heat treatment, and residual defects and secondary defects Is likely to occur.

As shown in FIG. 2C, after removing the photoresist 34, the SiN forming the membrane 21 is depressurized by CV.
Silicon substrate 2 at a substrate temperature of about 780 ° C. using the D method
0 is deposited on the main surface. On the membrane 21 thus deposited, as shown in FIG. 2D, an n-type polysilicon layer 23 and a p-type polysilicon layer 24 (see FIG.
Polysilicon (not shown in FIG. 3D) is deposited at a substrate temperature of about 620 ° C. using a low pressure CVD method, and patterned into a predetermined thin film shape.

Next, as shown in FIG. 2 (e), patterning is performed with a photoresist 35, and phosphorus ions are ion-implanted into polysilicon to form the n-type polysilicon layer 23. The dose is 5 × 10 ^15. Dope (cm ^-2 ) and anneal at 950 ° C for 20 minutes,
Electrically activate. After that, as shown in FIG. 2F, after removing the photoresist 35, patterning is performed with the photoresist 36, and boron ions are ion-implanted into the polysilicon to form the p-type polysilicon layer 24. Depending on dose 5 × 10 ¹⁵ (cm ^-2 )
After approximately doping, annealing is performed at 950 ° C. for about 20 minutes to electrically activate. Although the p-type polysilicon layer 24 is not shown in FIG. 2F, refer to FIG. 1 for the p-type polysilicon layer 24.

After forming the thermopile n-type polysilicon layer 23 and the p-type polysilicon layer 24 in this way, as shown in FIG. 3A, the n-type polysilicon layer 23 and the p-type polysilicon layer are formed on the membrane 21. An interlayer insulating film 29 between the layer 24 and the layer 24 is deposited, and a hot junction 25 is formed on the interlayer insulating film 29.
And a contact hole 37 for the cold junction 26 is formed. Next, as shown in FIG. 3B, Al—Si is deposited on the interlayer insulating film 29 by the sputtering method and patterned to form the hot contact 25 and the cold contact 26 in the contact hole 37. Then, as shown in FIG. 3C, PSN or plasma CVD is used to deposit SiN thereon to form a protective layer 30.

As shown in FIG. 3D, a rectangular etching solution that penetrates the membrane 21, the interlayer insulating film 29, and the protective layer 30 and reaches the defect layer 33 at the positions corresponding to the four corners of the defect layer 33. The inlet 32 is formed. Hydrazine, which is an anisotropic etching solution, is injected from each etching solution injection port 32 to etch the silicon substrate 20 and the defect layer 33. The liquid temperature during etching is about 80 ° C.

At this time, in the region of the defect layer 33 formed under the above-mentioned ion implantation conditions, the etching rate is increased by about 5 times as compared with the normal region which is not the defect layer 33, and is about 0.09.
It becomes μm / min. This etching rate characteristic is shown in FIG.

The membrane 2 is formed by such etching.
The etching progresses under 1 like under etching,
The isolation space 22 is formed by an inverted quadrangular pyramid-shaped depression having the entire surface of the defect layer 33 as the bottom surface, and the membrane structure is obtained here. Finally, as shown in FIG. 3F, Au-Black, which is the infrared absorption film 31, is deposited on the protective layer 30 and patterned.

In the infrared sensor having the above-mentioned structure, the incident infrared ray absorbed by the infrared absorbing film 31 is converted into heat, and the infrared absorbing film 31 is converted according to the amount of incident infrared ray.
Temperature rises. This heat is transmitted to the hot junction 25 by conduction, a temperature difference is generated between the hot junction 25 and the cold junction 26, and an electromotive force is generated in the thermopile by the Seebeck effect. In the configuration shown in FIG. 1, the thermoelectromotive force of the entire element is the sum of the electromotive force between the n-type polysilicon layer 23 and the contact point and the electromotive force between the p-type polysilicon layer 24 and the contact point. Is expressed by the following equation.

S = nαRthP where S: electromotive force n: n-type polysilicon layer 23 and p-type polysilicon layer 24
The number of thermocouples according to α: n-type polysilicon layer 23 and p-type polysilicon layer 24
Seebeck coefficient Rth: Thermal resistance P: Incident energy In order to increase the electromotive force S, it is necessary to use a material having a large Seebeck coefficient α and to increase the thermal resistance Rth.

The figure of merit D ^* of the thermal infrared sensor is represented by the following equation. D ^* = {1 / (4kT) ^1/2 } ・ Ad ^1/2・ n ・ α (Rth / Rd
^1/2 ) ・ (P / Pd) where Ad: area of infrared absorbing film Rd: electric resistance Pd: effective incident energy k: Boltzmann constant T: absolute temperature

This equation shows that in order to increase D ^* , the area Ad of the infrared absorbing film, the number n of thermocouples, the thermal resistance Rth and the energy transfer efficiency P / Pd are increased, and the electrical resistance Rd is decreased. Indicates that it is necessary. The thermal resistance Rth can be increased by thinning the membrane 21, the n-type polysilicon layer 23, and the p-type polysilicon layer 24.

In the thermal infrared sensor manufactured as described above, since the defect layer 33 to be removed by etching is formed not at the main surface of the semiconductor substrate 20 but at a predetermined depth within the main surface, the membrane 21, n-type polysilicon layer 2
3. No step is formed on the p-type polysilicon layer 24. As a result, the strength reliability of the membrane 21, and the n-type polysilicon layer 23 and the p-type polysilicon layer 24 forming the thermopile are improved, and the thinning of these increases the thermal resistance and improves the thermal separation. The sensor characteristics can be improved. The temperature sensitive element formed on the membrane 21 is not limited to the thermopile,
It may be a diode or a bolometer.

FIG. 5 shows another embodiment of the thermal infrared sensor manufactured by the manufacturing method according to the present invention. Note that, in FIG. 5, portions corresponding to those in FIG. 1 will be described by adding A to the reference numerals in FIG. In this embodiment, four sets of strip-shaped n-type polysilicon layers 23A constituting a thermopile,
The p-type polysilicon layer 24A is formed in an X shape with an angle of 45 degrees with the {110} direction of the silicon substrate 20A. In this case, a trapezoidal etching solution injection port 32A is formed in a triangular region between the n-type polysilicon layer 23A and the p-type polysilicon layer 24A which are adjacent to each other.
To form.

If etching is performed using hydrazine as it is, only the rectangular region 39 containing the etchant injection port 32A is etched depending on the plane orientation of the silicon substrate 20A. This rectangular area 3
A membrane structure cannot be formed if the 9's do not overlap each other. Therefore, the rectangular area 3
In the inner region of 9, the entire rectangular region that partially overlaps the rectangular region 39 is set as the defect layer 33A, so that the region of this defect layer 33A is also etched as in the above-described embodiment. Finally, the hatched area in FIG. 6 is etched to form the inverted quadrangular pyramid-shaped thermal separation chamber 22A having the hatched area as the bottom surface.

In this embodiment, the same effect as that of the above-mentioned embodiment is obtained, and most of the etching is performed on the substrate 2.
Since the etching is performed depending on the plane orientation of 0A and the portion that depends on the defect layer 33A is small, the etching time is shortened as compared with the above-described embodiment, and the productivity is improved, and (11
1) The amount of side etching on the surface can be reduced. In addition, the n-type polysilicon layer 23A and the p-type polysilicon layer 2
Since the thermopile of 4A is formed in the diagonal direction of the heat separation chamber 22A, the n-type polysilicon layers 23A, p
The type polysilicon layer 24A has a long length, which improves thermal isolation and improves sensor characteristics.

If a defect layer 33B having a large area as shown in FIG. 7 is formed, even if the etching solution injection port 32B is formed in a rectangular shape as shown, a rectangle as shown by reference numeral 22B becomes the bottom surface. An inverted quadrangular pyramidal thermal separation chamber is formed. In FIG. 7, a portion similar to the portion corresponding to FIG. 1 is denoted by B.

FIG. 8 shows an embodiment of a pressure sensor manufactured by the manufacturing method according to the present invention. In FIG. 8 as well, portions corresponding to those in FIG. 1 will be described by adding C to the reference numerals given in FIG. A defect layer 33C indicated by a broken line is formed on the main surface of the silicon substrate 20C as in the above-described embodiment, a rectangular etchant injection port 32C is formed in the center thereof, and the etchant is injected from the etchant injection port 32. To do. The defect layer 33C has an etching characteristic that anisotropy is weakened, but since it also has an isotropic etching characteristic, etching progresses in a direction parallel to the main surface, that is,
Etching does not stop at the (111) plane, and finally a quadrangular pyramid-shaped recess 22C having a rectangular shape slightly larger than the defect layer 33C as a bottom surface is formed, and a membrane structure is obtained.

A piezoresistive element 4 is provided on the membrane 21C.
Four 4 are formed and bridge-connected by the conductive connection body 45. 46 denotes a piezoresistive element 44 and a conductive connection body 45.
Is an electrode for connecting. After the etching solution injection port 32C is completely etched, it is sealed with a sealing material 42 made of polycrystalline silicon, an oxide film, a resin or the like to form the recess 22C in a hermetically sealed structure.

The recess 22C serves as a pressure reference chamber, and the pressure difference between the pressure reference chamber and the outside is detected as a change in the resistance value of the piezoresistive element 44 made of polycrystalline silicon. In this case, for example, when the external pressure becomes larger than the pressure in the pressure reference chamber 43, the membrane 21C bends inward, so that the two piezoresistive elements 44 in the center portion are compressed and the outer piezoresistive 44 is pulled. Since the bridge circuit is unbalanced due to the distortion, a potential difference occurs at the midpoint. The external pressure can be measured by this potential difference.

Also in this embodiment, since the membrane 21C is formed as a flat surface without a step and the piezoresistive element 44 can be arranged on the outer periphery of the membrane 21C, the improvement of the sensor characteristic and the high integration are compatible.

FIG. 9 shows an embodiment of an acceleration sensor manufactured by the manufacturing method according to the present invention. In FIG. 9, the portions corresponding to those in FIGS. 1 and 8 will be described by adding D to the reference numerals in FIGS. 1 and 8. This acceleration sensor has a so-called cantilever structure, and in this embodiment as well, it is manufactured by a procedure similar to the method described above. That is,
The defect layer 33D similar to that of the above-described embodiment is formed on the main surface of the silicon substrate 20D, and the etching solution injection ports 32D are formed at both upper and lower ends of the defect layer 33D in FIG. 9A. When the etchant is injected from the etchant inlet 32D, the defect layer 33D is formed in the same manner as described above.
In the region (2), the etching progresses also in the direction parallel to the main surface to form a concave portion 22D having a rectangular shape 22D 'as a bottom surface. 2 on each side of the beam by the membrane 21D
Piezoresistive elements 44D are formed one by one, and a weight 47 is formed in the center of the membrane 21D.

In this acceleration sensor, when downward acceleration is applied, the entire membrane 21D is displaced downward. As a result, compressive stress acts on the piezoresistive element 44D in the central part and tensile stress acts on the piezoresistive element 44D in the peripheral part, and like the pressure sensor described above, the balance of the bridge circuit is disturbed, so that the middle point A potential difference occurs. The acceleration can be known from this potential difference.

Also in this acceleration sensor, the membrane 21D is formed as a flat surface without a step. As a result, the piezoresistive element 44D can be arranged around the outer periphery of the membrane 21, and in this case as well, improvement in sensor characteristics and high integration can both be achieved.

In any of the above embodiments, the defect layer was formed as the crystal defect layer by the ion implantation method.
This may be formed by a sandblast method. Alternatively, the defect layer may be formed by immersing the silicon substrate in an HF solution and applying electric energy or light energy to the predetermined region to make the predetermined region of the silicon substrate porous.

[0039]

As described in detail above, according to the method of manufacturing the semiconductor sensor device of the present invention, the side etching rate of the (111) plane can be increased by forming the defect layer from the main surface to the inside of the semiconductor substrate. Since the recesses are formed to be increased in number, the membrane is formed in a flat surface without a step, the mechanical strength of the membrane is increased, and the strength reliability is improved. Further, since the entire area of the membrane is a flat surface, the thin film formed on the membrane such as a thermopile can be thinned, the degree of freedom in design is expanded, and the heat separation is improved, so that the sensor characteristics are improved. Further, there is an effect that the steps of forming and etching the polysilicon sacrificial layer are eliminated and the steps can be simplified.

[Brief description of drawings]

1A is a plan view showing an embodiment of a thermal infrared sensor manufactured by a manufacturing method according to the present invention, and FIG. 1B is a sectional view taken along line bb of FIG. 1A.

2A to 2F are process drawings showing a manufacturing process of the thermal infrared sensor shown in FIG.

3 (a) to 3 (f) are process charts showing the manufacturing process of the thermal infrared sensor shown in FIG. 1, showing the process following FIG. 2 (a) to (f).

FIG. 4 is a graph showing etching rate characteristics.

FIG. 5 is a plan view showing another embodiment of the thermal infrared sensor manufactured by the manufacturing method according to the present invention.

6 is a plan view showing an etching region of the thermal infrared sensor shown in FIG.

7 is a plan view showing an example in which the shape of a defect layer of the thermal infrared sensor shown in FIG. 5 is enlarged.

8A is a plan view showing an embodiment of a pressure sensor manufactured by the manufacturing method according to the present invention, and FIG. 8B is a plan view of FIG.
FIG. 6 is a sectional view taken along line bb of FIG.

9A is a plan view showing an embodiment of an acceleration sensor manufactured by a manufacturing method according to the present invention, and FIG. 9B is a sectional view taken along line bb of FIG. 9A.

10A is a plan view showing a thermal infrared sensor manufactured by a conventional manufacturing method, and FIG. 10B is a sectional view thereof.

FIG. 11 is a process diagram illustrating a method of manufacturing the conventional thermal infrared sensor of FIG.

[Explanation of symbols]

 20 Silicon Substrate 21 Membrane 22 Thermal Separation Chamber 23 n-type Polysilicon Layer 24 p-type Polysilicon Layer 25 Hot Junction 26 Cold Junction 29 Interlayer Insulating Film 30 Protective Film 31 Infrared Absorption Film 32 Etching Liquid Injection Port 33 Defect Layer 42 Encapsulant 43 Pressure reference chamber 44 Piezoresistive element 4 Weight

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H01L 35/32 A

Claims (8)

[Claims] 1. A recess formed on the main surface of a semiconductor substrate,
In a method of manufacturing a semiconductor sensor device including a membrane provided above the recess and a sensor element provided on the membrane, etching in which anisotropy is substantially weakened from the main surface to the inside of the semiconductor substrate. Forming a defect layer having characteristics over a predetermined depth, forming a membrane made of an etching resistant material on the main surface of the semiconductor substrate, and penetrating the membrane into the membrane to reach the defect layer A step of forming one etching solution injection port, and injecting an anisotropic etching solution into the etching solution injection port to remove the defect layer and anisotropically etch the semiconductor substrate from the portion where the defect layer is removed. And the step of forming the recessed portion by means of a step of forming the recessed portion. 2. The method for manufacturing a semiconductor sensor device according to claim 1, wherein the defect layer is formed as a crystal defect layer by a physical treatment such as an ion implantation method or a sandblast method. 3. The semiconductor substrate is a silicon substrate,
The method of manufacturing a semiconductor sensor device according to claim 1, wherein the defect layer is formed by implanting silicon ions. 4. The method of manufacturing a semiconductor sensor device according to claim 2, wherein the dose amount in the ion implantation does not exceed a critical dose amount for amorphizing the semiconductor substrate. 5. The method for manufacturing a semiconductor sensor device according to claim 1, wherein the defect layer is formed as a porous layer by a chemical porosification treatment. 6. The semiconductor substrate has a (100) plane as a main plane, the etching inlet formed in a membrane provided on the main plane has a triangular shape, and two sides of the triangular shape are (110). The method for manufacturing a semiconductor sensor device according to claim 1, wherein the semiconductor sensor device is formed at a predetermined angle with respect to the surface. 7. A semiconductor temperature sensor device manufactured by the manufacturing method according to claim 1, wherein a temperature sensitive element is formed on the membrane, and the recess is a thermal separation space. Temperature sensor device. 8. A semiconductor pressure sensor device manufactured by the manufacturing method according to claim 1, wherein the recess is used as a reference pressure chamber, and a membrane is formed according to a difference between the reference pressure chamber and the detected pressure. A semiconductor pressure sensor device in which a strain gauge type bridge circuit for outputting a signal according to the strain of the membrane is formed on the membrane so that the substrate is bent.