CN106395735A - Method for manufacturing resistive element, method for manufacturing pressure sensor element, pressure sensor element, pressure sensor - Google Patents

Abstract

The present invention provides a method of manufacturing a resistance element and a method of manufacturing a pressure sensor element capable of forming an extremely thin resistance region in a state of being buried at an extremely shallow position, and also provides a method capable of achieving miniaturization and high precision. A pressure sensor element, and a pressure sensor, an altimeter, an electronic device, and a mobile body including the pressure sensor element are provided. The manufacturing method of the resistance element of the present invention comprises: the operation of preparing a substrate (2) having an n-type silicon layer (213); the operation of forming a resistance region (51) by doping impurities into the silicon layer (213); A step of heat-treating the resistance region (51) by any one of thermal annealing, flash lamp annealing, and excimer laser annealing; and a step of forming a capping layer (213a) by epitaxially growing silicon on the resistance region (51).

Description

Respective manufacturing methods of resistance element and pressure sensor element, pressure sensor components, pressure sensors

technical field

The present invention relates to a method of manufacturing a resistance element, a method of manufacturing a pressure sensor element, a pressure sensor element, a pressure sensor, an altimeter, an electronic device, and a moving body.

Background technique

In micro-electro-mechanical systems (MEMS) (in particular, sensor devices), a method of doping single crystal silicon with impurities to form resistance elements (piezoelectric resistance elements) is widely used.

As a method for manufacturing such a resistance element, for example, as disclosed in Patent Document 1, boron is accelerated to an energy of 1 MeV and implanted into an n-type silicon substrate, thereby leaving an n-type layer on the substrate surface. A method of forming a p-type resistive layer (resistive region) in the state. By embedding the resistive layer in the formed resistive element by this method, the influence of an external electric field can be reduced.

However, in the method described in Patent Document 1, since the resistive layer is formed at a relatively deep position, there is a problem that, for example, when a resistive element is used for deflection detection of an extremely thin diaphragm, It is difficult to bury the resistive layer so that it is biased toward one side of the diaphragm so that the efficiency can be tested.

Patent Document 1: Japanese Patent Application Laid-Open No. 7-131035

Contents of the invention

The object of the present invention is to provide a method of manufacturing a resistance element and a method of manufacturing a pressure sensor element in which an extremely thin resistance region can be buried at an extremely shallow position. A pressure sensor element with improved and higher precision, and a pressure sensor, an altimeter, an electronic device, and a mobile body including the pressure sensor element are provided.

Such objects are achieved by the present invention described below.

Application example 1

The method for manufacturing a resistance element according to the present invention is characterized in that it includes: a step of preparing a substrate having a silicon layer having an n-type or p-type region; and a step of forming a resistance region by doping the region with an impurity. ; a process of heat-treating the resistance region by any one of rapid thermal annealing, flash lamp annealing, and excimer laser annealing; and a process of forming a capping layer by epitaxially growing silicon on the resistance region.

According to this method of manufacturing a resistance element, since the resistance region is heat-treated by any one of rapid thermal annealing, flash lamp annealing, and excimer laser annealing, the thermal budget (thermal history) is low, enabling reduction in Diffusion of impurities activates the resistive region while leaving it shallow. In addition, in the obtained resistance element, since the resistance region is covered and buried with the cover layer, it is possible to reduce the incorporation of noise into the resistance region. In particular, since the capping layer can be formed by epitaxial growth, it is possible to bury the resistance region at an extremely shallow position while making the thickness of the resistance region extremely thin.

Application example 2

In the method for manufacturing a resistor element according to the present invention, it is preferable that the epitaxial growth is performed using disilane gas in the step of forming the capping layer.

Thus, the covering layer can be formed at a relatively low temperature. Therefore, it is possible to reduce diffusion of the resistive region in the step of forming the cover layer.

Application example 3

In the method for manufacturing a resistor element according to the present invention, preferably, in the step of performing the heat treatment, the thickness of the resistor region after the heat treatment is in a range of 0.1 μm to 2.0 μm.

Thus, for example, when a resistance element is provided as a strain detection element in a diaphragm portion that is flexed and deformed by pressure, even if the diaphragm portion is made extremely thin, the resistance region can be biased toward the surface of the diaphragm portion. nearby, so that the detection accuracy of the resistance element can be excellent.

Application example 4

In the method for manufacturing a resistor element according to the present invention, preferably, in the step of forming the covering layer, the thickness of the covering layer is in a range of 0.05 μm to 0.4 μm.

Thus, for example, when a resistance element is provided as a strain detection element in a diaphragm portion that is flexed and deformed by pressure, even if the diaphragm portion is made extremely thin, the resistance region can be biased toward the surface of the diaphragm portion. nearby, so that the detection accuracy of the resistance element can be excellent.

Application example 5

The manufacturing method of the pressure sensor element of the present invention is characterized in that it includes: the steps of forming a resistive element using the manufacturing method of the resistive element of the present invention; Diaphragm process.

According to such a method of manufacturing a pressure sensor element, in the obtained pressure sensor element, even if the diaphragm portion is made extremely thin, the resistance region can be shifted to the vicinity of the surface of the diaphragm portion, and the detection accuracy of the resistance element can be made excellent. . In addition, since the resistive region is buried by being covered with the cover layer in the obtained pressure sensor element, it is possible to reduce the mixing of noise into the resistive region. Thereby, miniaturization and high precision of the obtained pressure sensor element can be achieved.

Application example 6

The pressure sensor element of the present invention is characterized in that it has a diaphragm portion including: a silicon layer; and a resistance element having a resistance region containing carriers in the silicon layer and generating an electrical signal corresponding to deformation. the cover layer on the resistance region, the thickness of the resistance region is in the range of 5% to 30% of the thickness of the diaphragm part, and the surface of the diaphragm part on the side of the cover layer and A distance between peak positions of carrier concentration in the resistance region is within a range of 2% to 40% of the thickness of the diaphragm portion.

According to such a pressure sensor element, even if the diaphragm portion is provided extremely thin, the resistance element can be positioned near the surface of the diaphragm portion, and the detection accuracy of the resistance element can be improved. In addition, since the resistive region is buried by being covered with the cover layer, it is possible to reduce the mixing of noise into the resistive region. Thereby, miniaturization and high precision of the pressure sensor element can be realized.

Application example 7

In the pressure sensor element of the present invention, it is preferable to include a pressure reference chamber provided on the cover layer side.

Accordingly, it is possible to realize a pressure sensor element that detects pressure using the pressure of the pressure reference chamber as a reference.

Application example 8

In the pressure sensor element of the present invention, it is preferable that the thickness of the diaphragm part is in the range of 0.5 μm or more and 15 μm or less.

Thus, a small pressure sensor element can be realized.

Application example 9

In the pressure sensor element of the present invention, preferably, the thickness of the resistance region is in a range of 0.1 μm or more and 2.0 μm or less.

Thereby, even if the diaphragm part is provided extremely thin, the resistance region can be shifted toward the vicinity of the surface of the diaphragm part, and the detection accuracy of the resistance element can be made excellent.

Application Example 10

In the pressure sensor element according to the present invention, preferably, the distance between the surface of the diaphragm portion on the cover layer side and the peak position of the carrier concentration of the resistance region is 0.05 μm or more and 0.4 μm or less. In the range.

Thereby, even if the diaphragm part is provided extremely thin, the resistance region can be shifted toward the vicinity of the surface of the diaphragm part, and the detection accuracy of the resistance element can be made excellent.

Application Example 11

In the pressure sensor element of the present invention, it is preferable to include a substrate having the diaphragm portion and the circuit portion.

Accordingly, it is possible to realize a pressure sensor element in which the diaphragm unit and the circuit unit are integrated on one chip.

Application example 12

The pressure sensor of the present invention is characterized by comprising the pressure sensor element of the present invention.

According to such a pressure sensor, it is possible to reduce the size and increase the precision of the pressure sensor element.

Application Example 13

The altimeter of the present invention is characterized by including the pressure sensor element of the present invention.

According to such an altimeter, it is possible to reduce the size and increase the precision of the pressure sensor element.

Application example 14

An electronic device of the present invention includes the pressure sensor element of the present invention.

According to such an electronic device, it is possible to realize miniaturization and high precision of the pressure sensor element.

Application Example 15

The mobile body of the present invention is characterized by including the pressure sensor element of the present invention.

According to such a moving body, it is possible to reduce the size and increase the precision of the pressure sensor element.

Description of drawings

FIG. 1 is a cross-sectional view showing a pressure sensor element according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an arrangement of resistive elements included in the pressure sensor element shown in FIG. 1 .

FIG. 3 is a graph showing an example of a carrier concentration distribution in a resistance region of the resistance element shown in FIG. 2 .

Fig. 4 is a view for explaining the action of the pressure sensor element shown in Fig. 1, (a) is a cross-sectional view showing a pressurized state, and (b) is a plan view showing a pressurized state.

FIG. 5 is a view showing a manufacturing process (forming a resistive element) of the pressure sensor element shown in FIG. 1 .

FIG. 6 is a graph showing an example of the carrier concentration distribution of the annealed resistance element shown in FIG. 5 .

FIG. 7 is a view showing manufacturing steps (steps of forming an insulating layer, a circuit portion, etc.) of the pressure sensor element shown in FIG. 1 .

FIG. 8 is a view showing a manufacturing process of the pressure sensor element shown in FIG. 1 (a forming process of a pressure reference chamber, a diaphragm portion, and the like).

9 is a cross-sectional view showing a pressure sensor element according to a second embodiment of the present invention.

Fig. 10 is a sectional view of an example of the pressure sensor of the present invention.

Fig. 11 is a perspective view showing an example of the altimeter of the present invention.

Fig. 12 is a front view showing an example of the electronic device of the present invention.

Fig. 13 is a perspective view showing an example of the moving body of the present invention.

detailed description

Hereinafter, the pressure sensor element, the pressure sensor, the altimeter, the electronic device, and the mobile body of the present invention will be described in detail based on the respective embodiments shown in the drawings.

1. Pressure sensor element

first embodiment

1 is a cross-sectional view showing a pressure sensor element according to a first embodiment of the present invention, and FIG. 2 is a plan view showing an arrangement of resistive elements included in the pressure sensor element shown in FIG. 1 . FIG. 3 is a graph showing an example of a carrier concentration distribution in a resistance region of the resistance element shown in FIG. 2 . 4 is a diagram for explaining the action of the pressure sensor element shown in FIG. 1, FIG. 4(a) is a sectional view showing a pressurized state, and FIG. 4(b) is a plan view showing a pressurized state. In addition, in the following, for convenience of explanation, the upper side in FIG. 1 is called "upper", and the lower side is called "lower".

The pressure sensor element 1 shown in FIG. 1 includes: a substrate 2 having a diaphragm portion 20; a plurality of piezoresistive elements 5 (resistive elements) provided in the diaphragm portion 20; Reference chamber) laminated structure 6; semiconductor circuit 9 (circuit part).

Hereinafter, each part constituting the pressure sensor element 1 will be described in order.

Substrate

The substrate 2 has a semiconductor substrate 21 , an insulating film 22 provided on one surface of the semiconductor substrate 21 , and an insulating film 23 provided on the surface of the insulating film 22 opposite to the semiconductor substrate 21 .

The semiconductor substrate 21 is formed by sequentially laminating a silicon layer 211 (handle layer) made of single crystal silicon, a silicon oxide layer 212 (box layer) made of silicon oxide film, and a layer made of single crystal silicon. An SOI (Silicon On Insulator: silicon-on-insulator) substrate comprising a silicon layer 213 (device layer). In addition, the semiconductor substrate 21 is not limited to an SOI substrate, and may be other semiconductor substrates such as a single crystal silicon substrate, for example.

The insulating film 22 is, for example, a silicon oxide film and has insulating properties. In addition, the insulating film 23 is, for example, a silicon nitride film, has insulating properties, and also has resistance to an etchant containing hydrofluoric acid. Here, since the insulating film 22 (silicon oxide film) is interposed between the semiconductor substrate 21 (silicon layer 213) and the insulating film 23 (silicon nitride film), the time for forming the insulating film 23 can be eased by the insulating film 22. The generated stress is transmitted to the semiconductor substrate 21 . In addition, the insulating film 22 can be used as an element separation film of the semiconductor circuit 9 . In addition, the insulating films 22 and 23 are not limited to the constituent materials described above, and either one of the insulating films 22 and 23 may be omitted as necessary.

On such a substrate 2, there is provided a diaphragm portion 20 which is thinner than the surrounding portion and flexibly deformed by being pressed. The diaphragm portion 20 is formed by providing a bottomed concave portion 24 on the lower surface of the semiconductor substrate 21 . The lower surface of the diaphragm portion 20 serves as a pressure receiving surface 25 . In this embodiment, as shown in FIG. 2 , the diaphragm portion 20 has a square (rectangular) planar shape.

In the substrate 2 of the present embodiment, the concave portion 24 penetrates the silicon layer 211 , and the diaphragm portion 20 is constituted by four layers of the silicon oxide layer 212 , the silicon layer 213 , the insulating film 22 , and the insulating film 23 . Here, as will be described later, the silicon oxide layer 212 can be used as an etching stopper layer when forming the recessed portion 24 by etching in the manufacturing process of the pressure sensor element 1, and the thickness of the diaphragm portion 20 can be reduced every time. Deviations in individual products.

In addition, the recess 24 does not need to penetrate the silicon layer 211 , and the diaphragm portion 20 is constituted by five layers of the thin portion of the silicon layer 211 , the silicon oxide layer 212 , the silicon layer 213 , the insulating film 22 , and the insulating film 23 .

Piezoelectric resistance element (resistive element)

As shown in FIG. 1 , a plurality of piezoresistive elements 5 are respectively formed on the cavity S side of the diaphragm portion 20 . Here, the piezoelectric resistance element 5 is formed in the silicon layer 213 of the semiconductor substrate 21 .

As shown in FIG. 2 , the plurality of piezoresistor elements 5 are constituted by a plurality of piezoresistor elements 5 a , 5 b , 5 c , and 5 d arranged on the outer peripheral portion of the diaphragm portion 20 .

The piezoresistive element 5 a and the piezoresistive element 5 b are arranged corresponding to the four sides of the quadrilateral diaphragm portion 20 when viewed from above in the thickness direction of the substrate 2 (hereinafter simply referred to as “planar view”). , piezoresistive element 5c, piezoresistive element 5d.

The piezoelectric resistance element 5 a has a resistance region 51 a extending in a direction perpendicular to the corresponding side of the diaphragm portion 20 . A pair of wirings 214a are electrically connected to both ends of the resistance region 51a. Similarly, the piezoelectric resistance element 5 b has a resistance region 51 b extending in a direction perpendicular to the corresponding side of the diaphragm portion 20 . A pair of wirings 214b are electrically connected to both ends of the resistance region 51b.

On the other hand, the piezoelectric resistance element 5 c has a resistance region 51 c extending in a direction parallel to the corresponding side of the diaphragm portion 20 . A pair of wirings 214c are electrically connected to both ends of the resistance region 51c. Similarly, the piezoelectric resistance element 5 d has a resistance region 51 d extending in a direction parallel to the corresponding side of the diaphragm portion 20 . A pair of wirings 214d are electrically connected to both ends of the resistance region 51d.

Although not shown in the figure, the wirings 214a, 214b, 214c, and 214d each have portions exposed on the upper surface of the semiconductor substrate 21, and the wirings 214a, 214b, 214c, and 214d are electrically connected to the semiconductor circuit 9 via the portions. .

In addition, hereinafter, the resistance regions 51a, 51b, 51c, and 51d are also collectively referred to as "resistance region 51", and the wirings 214a, 214b, 214c, and 214d are also collectively referred to as "wiring 214".

The resistance region 51 and the wiring 214 of the piezoresistive element 5 are doped (diffused or Injection) is formed. Here, the doping concentration of impurities in the wiring 214 is higher than the doping concentration of impurities in the resistance region 51 . In addition, at least a part of the wiring 214 may be made of metal.

Such a carrier-containing resistive region 51 and wiring 214 are buried in the silicon layer 213 of the diaphragm portion 20 . That is, the upper surfaces of the resistance region 51 and the wiring 214 are covered with the cover layer 213 a made of single crystal silicon of a conductivity type different from that of the resistance region 51 and the wiring 214 .

Here, the conductivity type of the resistance region 51 and the wiring 214 is different from that of the silicon layer 213 except for the resistance region 51 and the wiring 214 . That is, when the resistance region 51 and the wiring 214 are p-type, the part of the silicon layer 213 other than the resistance region 51 and the wiring 214 is n-type, and the cladding layer 213a is also n-type. And when the wiring 214 is n-type, the part of the silicon layer 213 other than the resistance region 51 and the wiring 214 is p-type, and the cladding layer 213a is also p-type. In this way, a pn junction is formed between the resistance region 51 and the wiring 214 and the portion of the silicon layer 213 other than the resistance region 51 and the wiring 214 . Thereby, leakage current from the resistance region 51 and the wiring 214 can be reduced.

The conductivity type of the resistance region 51 and the wiring 214 may be either p-type or n-type, but is preferably p-type. Accordingly, the detection sensitivity of the piezoresistive element 5 can be made excellent. In addition, below, the case where the resistance region 51 and the wiring 214 are p-type is demonstrated.

In addition, as shown in FIG. 3 , the thickness _t2 of the resistance region 51 is the thickness of the p-type region, which is in the range of 5% to 30% of the thickness _t1 of the diaphragm part 20, and the covering layer of the diaphragm part 20 The distance L between the surface on the 213a side and the peak position of the carrier concentration of the resistance region 51 is within the range of 2% to 40% of the thickness _t1 of the diaphragm portion 20 . Accordingly, it is possible to make the diaphragm portion 20 extremely thin, and at the same time displace the resistive region 51 toward the vicinity of the surface of the diaphragm portion 20 , so that the detection accuracy of the piezoresistive element 5 can be made excellent. In addition, since the resistance region 51 is buried, it is possible to reduce the mixing of noise into the resistance region 51 . Accordingly, it is possible to realize downsizing and high precision of the pressure sensor element 1 .

Here, the thickness _t1 of the diaphragm portion 20 is preferably in the range of 0.5 μm to 15 μm, more preferably in the range of 0.5 μm to 5 μm, and still more preferably in the range of 0.5 μm to 4 μm. . Thereby, even if the width is made small, the diaphragm portion 20 can be deflected and deformed by receiving pressure, and as a result, a compact pressure sensor element 1 can be realized.

In addition, the width w of the diaphragm portion 20 is preferably in the range of 50 μm to 500 μm, more preferably in the range of 50 μm to 200 μm, and still more preferably in the range of 80 μm to 200 μm. Thus, a compact pressure sensor element 1 can be realized.

In addition, the thickness _t2 of the resistance region 51 is preferably in the range of 0.1 μm to 2.0 μm, more preferably in the range of 0.1 μm to 1.0 μm, still more preferably in the range of 0.1 μm to 0.5 μm. within range. Accordingly, it is possible to make the diaphragm portion 20 extremely thin, and at the same time displace the resistive region 51 toward the vicinity of the surface of the diaphragm portion 20 , so that the accuracy of the piezoresistive element 5 can be improved.

In addition, the distance L between the surface of the diaphragm portion 20 on the side of the cover layer 213a and the peak position of the carrier concentration of the resistance region 51 is preferably in the range of 0.05 μm to 0.4 μm, more preferably 0.1 μm. It is within the range of 0.4 μm or more, more preferably within the range of 0.1 μm or more and 0.3 μm or less. Thereby, even if the diaphragm part 20 is provided extremely thin, the resistance region 51 can be deviated to the vicinity of the surface of the diaphragm part 20, and the detection accuracy of the piezoresistive element 5 can be made excellent.

In addition, the thickness of the covering layer 213a is preferably in the range of 0.05 μm to 0.4 μm, more preferably in the range of 0.05 μm to 0.20 μm, and still more preferably in the range of 0.05 μm to 0.10 μm. . Accordingly, even if the diaphragm portion 20 is made extremely thin, the resistive region 51 can be shifted toward the vicinity of the surface of the diaphragm portion 20 , and the incorporation of noise into the resistive region 51 can be reduced.

The piezoelectric resistance element 5 described above constitutes a bridge circuit (Wheatstone bridge circuit) via the wiring 214 and the like. A drive circuit (not shown) that supplies a drive voltage is connected to the bridge circuit. Furthermore, the bridge circuit outputs a signal (voltage) corresponding to the resistance value of the piezoelectric resistance element 5 . In this way, the piezoresistive element 5 generates an electrical signal through deformation.

Here, the plurality of piezoresistive elements 5 are configured such that resistance values in a natural state are equal to each other, for example.

laminated structure

The laminated structure 6 is formed so that the cavity S is defined between it and the above-mentioned substrate 2 . Here, the laminated structure 6 is disposed on the piezoresistive element 5 side of the diaphragm portion 20 , and defines (constitutes) a hollow portion S (internal space) together with the diaphragm portion 20 (or substrate 2 ).

This laminated structure 6 has: an interlayer insulating film 61 formed on the substrate 2 so as to surround the piezoelectric resistance element 5 in plan view; a wiring layer 62 formed on the interlayer insulating film 61; The interlayer insulating film 63 formed on the wiring layer 62 and the interlayer insulating film 61 ; layer 64 ; a surface protection film 65 formed on the wiring layer 64 and the interlayer insulating film 63 ; and a sealing layer 66 provided on the cover layer 641 .

The interlayer insulating films 61 and 63 are each made of, for example, a silicon oxide film. In addition, the wiring layers 62 and 64 and the sealing layer 66 are each made of metal such as aluminum. In addition, the sealing layer 66 seals the pores 642 included in the covering layer 641 . In addition, the surface protection film 65 is, for example, a silicon nitride film.

Furthermore, the semiconductor circuit 9 is fabricated on and above the semiconductor substrate 21 . This semiconductor circuit 9 has: active elements such as MOS transistor 67; Other capacitors, inductors, resistors, diodes, and wiring (including wiring 214 connected to piezoresistive element 5, wiring layer 62, 64) and other circuit components. Here, the MOS transistor 67 has: a source and a drain (not shown) formed by doping impurities such as phosphorus and boron on the upper surface of the semiconductor substrate 21; and a trench formed between the source and the drain. a gate insulating film (not shown) formed on the channel region; and a gate electrode 671 formed on the gate insulating film.

Such laminated structure 6 and semiconductor circuit 9 can be formed using a semiconductor manufacturing process such as a CMOS process.

In this way, since the substrate 2 has the diaphragm portion 20 and the semiconductor circuit 9 , it is possible to realize the pressure sensor element 1 in which the diaphragm portion 20 and the semiconductor circuit 9 are integrated on one chip.

The hollow portion S defined by the substrate 2 and the laminated structure 6 is a closed space. The hollow portion S is provided on the side of the diaphragm portion 20 opposite to the pressure receiving surface 25 , and functions as a pressure reference chamber serving as a reference value of the pressure detected by the pressure sensor element 1 . In this embodiment, the hollow part S is in a vacuum state (300 Pa or less). By setting the hollow portion S in a vacuum state, the pressure sensor element 1 can be used as an "absolute pressure sensor" that detects pressure based on the vacuum state, thereby improving its convenience.

However, the hollow portion S may not be in a vacuum state but may be in an atmospheric pressure state, may be in a decompressed state with an air pressure lower than the atmospheric pressure, or may be in a pressurized state with an air pressure higher than the atmospheric pressure. In addition, an inert gas such as nitrogen gas or a rare gas may be filled in the hollow portion S. As shown in FIG.

The structure of the pressure sensor element 1 has been briefly described above. In the pressure sensor element 1 having such a structure, as shown in FIG. As shown, the piezoresistive elements 5a, 5b, 5c, and 5d are deformed, and the resistance values of the piezoresistive elements 5a, 5b, 5c, and 5d change. Accompanying this, the output of the bridge circuit composed of the piezoresistive elements 5a, 5b, 5c, and 5d changes, and from this output, the magnitude of the pressure received by the pressure receiving surface 25 can be obtained.

More specifically, in the natural state before the above-mentioned deformation of the diaphragm portion 20 occurs, for example, when the resistance values of the piezoresistive elements 5a, 5b, 5c, and 5d are equal to each other, the piezoelectric resistance The product of the resistance values of the resistive elements 5a and 5b is equal to the product of the resistance values of the piezoresistive elements 5c and 5d, so that the output (potential difference) of the bridge circuit becomes zero.

On the other hand, when the diaphragm portion 20 is deformed as described above, as shown in FIG. Compressive deformation and tensile deformation along the width direction, and tensile deformation along the longitudinal direction and compressive deformation along the width direction occur in the resistance regions 51c, 51d of the piezoresistive elements 5c, 5d. Therefore, when the deformation of the diaphragm portion 20 occurs as described above, the resistance value of one of the resistance values of the piezoresistor elements 5a, 5b and the resistance values of the piezoresistor elements 5c, 5d increases, On the other hand, the resistance value will decrease.

Through the deformation of such piezoresistive elements 5a, 5b, 5c, and 5d, the difference between the product of the resistance values of the piezoresistive elements 5a, 5b and the product of the resistance values of the piezoresistive elements 5c, 5d, and the difference The corresponding output (potential difference) will be output from the bridge circuit. From the output from the bridge circuit, the magnitude of the pressure (absolute pressure) received by the pressure receiving surface 25 can be obtained.

Here, when the deformation of the diaphragm portion 20 occurs as described above, the resistance value of one of the resistance values of the piezoresistor elements 5a, 5b and the resistance values of the piezoresistor elements 5c, 5d will change. increase, and the resistance value of the other side will decrease, so the change in the difference between the product of the resistance values of the piezoresistive elements 5a, 5b and the product of the resistance values of the piezoresistive elements 5c, 5d can be increased, and with this, The output from the bridge circuit can be increased. As a result, the detection sensitivity of pressure can be improved.

With the pressure sensor element 1 configured as described above, the diaphragm portion 20 can be made extremely thin, and the resistive region 51 can be shifted toward the vicinity of the surface of the diaphragm portion 20, so that the piezoresistive element 5 can The detection accuracy is excellent. In addition, since the resistive region 51 is covered and buried with the cover layer 213 a, it is possible to reduce the mixing of noise into the resistive region 51 . Accordingly, it is possible to realize downsizing and high precision of the pressure sensor element 1 .

In addition, the pressure sensor element 1 configured as described above can be manufactured using the manufacturing method described below.

Manufacturing method of pressure sensor element

Next, the method of manufacturing the pressure sensor element of the present invention will be described by taking the method of manufacturing the pressure sensor element 1 described above as an example.

5 is a diagram showing the manufacturing process of the pressure sensor element shown in FIG. 1 (the forming process of the resistive element), and FIG. 6 is a graph showing an example of the carrier concentration distribution of the resistive element shown in FIG. 5 after annealing. picture. FIG. 7 is a view showing manufacturing steps (steps of forming an insulating layer, a circuit portion, etc.) of the pressure sensor element shown in FIG. 1 . FIG. 8 is a view showing a manufacturing process of the pressure sensor element shown in FIG. 1 (a forming process of a pressure reference chamber, a diaphragm portion, and the like).

The manufacturing method of the pressure sensor element 1 includes: [1] the process of forming the piezoelectric resistance element 5; [2] the process of forming the insulating films 22 and 23; [3] the process of forming the laminated structure 6 and the semiconductor circuit 9; [ 4] A step of forming the diaphragm portion 20 .

Hereinafter, each step will be described in order.

[1] Process of forming a piezoresistive element (manufacturing method of a resistive element)

1-1 Process of preparing substrate

First, as shown in FIG. 5( a ), prepare a semiconductor substrate 21 in which a silicon layer 211 (handle layer) made of single crystal silicon and a silicon oxide film are sequentially laminated. An SOI substrate comprising a silicon oxide layer 212 (box layer) and a silicon layer 213 (device layer) made of single crystal silicon.

In this embodiment, the silicon layer 213 has n-type conductivity.

1-2 Process of forming resistance region

Then, by doping (ion implantation) impurities such as boron (p-type) into the silicon layer 213 (n-type region) of the semiconductor substrate 21, as shown in FIG. line 214.

For example, when boron is implanted with ions at +80 keV, the ion implantation concentration into the piezoelectric resistance element 5 is set to about 1×10 ¹⁴ atoms/cm ² . In addition, the concentration of ion implantation into the wiring 214 is set higher than that of the piezoresistive element 5 . For example, when boron is ion-implanted at 10 keV, the ion implantation concentration into the wiring 214 is set to about 5×10 ¹⁵ atoms/cm ² .

1-3 heat treatment process

Next, as shown in FIG. 5( c ), the resistance region 51 and the wiring 214 are heat-treated by annealing. Accordingly, the resistance region 51 and the wiring 214 can be activated, and the electrical characteristics of the resistance region 51 and the wiring 214 can be improved.

In particular, the annealing used in this step 1-3 is any one of rapid thermal annealing (Rapid Thermal Anneal: RTA), flash lamp annealing (Flash Lamp Anneal: FLA) and excimer laser annealing (Excimer Laser Anneal: ELA). Kind of annealing (short time annealing). These anneals are all anneals with a low thermal budget (thermal history). Therefore, by using any one of these annealing, it is possible to reduce the diffusion of impurities. Therefore, it is possible to reduce the increase in the thickness of the resistance region 51 after the heat treatment or the shift of the peak position of the carrier concentration of the resistance region 51 to a deeper position. Thereby, for example, as shown in FIG. 6 , the resistive region 51 can be activated while leaving the resistive region 51 at a shallow position.

On the other hand, for example, when heat treatment is performed using furnace annealing performed in a furnace, dopants tend to diffuse because of a high thermal budget (thermal history). Therefore, the increase in the thickness of the resistance region 51 after the heat treatment and the shift of the peak position of the carrier concentration of the resistance region 51 to a deeper position are large. Therefore, even if the resistive region 51 has been formed at a thinner and shallower position in the aforementioned process 1-2, it is difficult to form the resistive region 51 at a thinner and shallower position. When the thickness of the diaphragm part 20 is thick, even if the resistive region 51 is relatively thick or located at a deep position, the resistive region 51 can be deviated to the surface side of the diaphragm part 20, so there is no problem. When the thickness of the portion 20 is extremely thin, the resistive region 51 cannot be shifted toward the surface side of the diaphragm portion 20 , and it is difficult to detect the efficiency by the piezoresistive element 5 .

In addition, in the heat treatment in this step 1-3, the resistance region 51 and the wiring 214 are heated to about 1000° C.

In addition, in this step 1-3, the thickness _t2 of the resistance region 51 after the heat treatment is preferably in the range of 0.1 μm to 2.0 μm, more preferably in the range of 0.1 μm to 1.0 μm, and furthermore Preferably, it exists in the range of 0.1 micrometer or more and 0.5 micrometer or less. Accordingly, even if the diaphragm portion 20 is made extremely thin (for example, 4 μm or less), the resistive region 51 can be shifted to the vicinity of the surface of the diaphragm portion 20 , and the detection accuracy of the piezoresistive element 5 can be improved.

In addition, in this step _1-3 , the distance L1 between the peak position of the carrier concentration of the resistance region 51 after heat treatment and the surface of the silicon layer 213 is preferably in the range of 0.05 μm or more and 1.0 μm or less, More preferably, it exists in the range of 0.05 micrometer or more and 0.5 micrometer or less, More preferably, it exists in the range of 0.05 micrometer or more and 0.25 micrometer or less. Accordingly, even if the diaphragm portion 20 is made extremely thin (for example, 4 μm or less), the resistance region 51 can be shifted to the vicinity of the surface of the diaphragm portion 20 , and the detection accuracy of the piezoresistive element 5 can be improved.

1-4 Process of forming the covering layer

Next, as shown in FIG. 5( d ), a cover layer 213 a is formed on the resistance region 51 and the wiring 214 .

The formation of the capping layer 213a is carried out by epitaxially growing silicon. Thereby, the resistive region 51 and the wiring 214 can be covered and buried with the cover layer 213a. Therefore, it is possible to reduce the mixing of noise into the resistance region 51 and the wiring 214 . In particular, since the capping layer 213a is formed by epitaxial growth, unlike the method described in Patent Document 1, the thickness of the resistance region 51 can be made extremely thin, and the resistance region 51 can be buried at an extremely shallow position. place.

In addition, although the source gas used for the epitaxial growth in this step 1-4 is not particularly limited, examples thereof include disilane (Si ₂ H ₆ ) gas, dichlorosilane (SiH ₂ Cl ₂ ) As the gas, it is preferable to use disilane gas. By performing epitaxial growth using disilane gas, the capping layer 213 a can be formed at a relatively low temperature (about 450° C.). Therefore, it is possible to reduce the diffusion of the resistance region 51 in the step 1-4 of forming the cover layer 213a.

In addition, when epitaxial growth is performed, for example, a dopant gas such as phosphorus is appropriately mixed into the source gas to form the cladding layer 213a of a desired conductivity type (n-type) or conductivity. In addition, in the case of forming the p-type cladding layer 213a, for example, it is only necessary to mix a gas such as boron into the source gas.

In addition, in this step 1-4, the thickness of the covering layer 213a is preferably in the range of 0.05 μm to 0.4 μm, more preferably in the range of 0.05 μm to 0.3 μm, still more preferably 0.1 μm In the range of above and below 0.2 μm. Thereby, even if the diaphragm part 20 is provided extremely thin, the resistance region 51 can be deviated to the vicinity of the surface of the diaphragm part 20, and the detection accuracy of the piezoresistive element 5 can be made excellent.

According to the manufacturing method of the piezoelectric resistance element 5 as above, since the resistance region 51 is heat-treated by any one of rapid thermal annealing, flash lamp annealing, and excimer laser annealing, the thermal budget (thermal history) is low, Accordingly, the resistance region 51 can be activated while reducing the diffusion of impurities and leaving the resistance region 51 at a shallow position. In addition, in the obtained piezoresistive element 5 , since the resistance region 51 is covered and buried with the cover layer 213 a , it is possible to reduce the mixing of noise into the resistance region 51 . In particular, since the capping layer 213a is formed by epitaxial growth, the resistance region 51 can be buried at an extremely shallow position while making the thickness of the resistance region 51 extremely thin.

[2] Step of forming insulating films 22 and 23

Next, as shown in FIG. 7( a ), an insulating film 22 and an insulating film 23 are sequentially formed on the silicon layer 213 .

The formation of insulating films 22 and 23 can be performed by, for example, sputtering, CVD (Chemical Vapor Deposition: Chemical Vapor Deposition) or the like.

[3] Step of forming laminated structure 6 and semiconductor circuit 9

3-1 Formation of MOS transistor 67

Next, as shown in FIG. 7( b ), a MOS transistor 67 is formed on the silicon layer 213 .

Here, the formation of the MOS transistor 67 can be implemented using a known semiconductor manufacturing process.

3-2 Interlayer insulating film and wiring layer formation process

Next, as shown in FIG. 7(c), a sacrificial layer 41, a wiring layer 62, a sacrificial layer 42, a wiring layer 64, and a surface protection film are sequentially formed to cover the insulating film 23, the MOS transistor 67, and the like. 65.

A part of each of the sacrificial layers 41 and 42 is removed by a cavity forming step described later, and the remaining parts become interlayer insulating films 61 and 63 . The formation of the sacrificial layers 41 and 42 is performed by forming a silicon oxide film by a sputtering method, a CVD method, or the like, and patterning the silicon oxide film by etching.

In addition, the respective thicknesses of the sacrificial layers 41 and 42 are not particularly limited, and are, for example, about 1500 nm or more and 5000 nm or less.

In addition, the formation of the wiring layers 62 and 64 is carried out by forming a layer made of, for example, aluminum or the like by a sputtering method, a CVD method, or the like, and then patterning the layer.

Here, the respective thicknesses of the wiring layers 62 and 64 are not particularly limited, and are, for example, about 300 nm or more and 900 nm or less.

A laminated structure composed of such sacrificial layers 41, 42 and wiring layers 62, 64 is formed using a normal CMOS process, and the number of laminations is appropriately set as necessary. That is, more sacrificial layers or wiring layers may be laminated as necessary.

In addition, the formation of the surface protection film 65 can be implemented by a sputtering method, a CVD method, etc., for example. Thereby, when performing the etching in the process 3-3 mentioned later, the part which becomes the interlayer insulating film 61, 63 of the sacrificial layer 41, 42 can be protected. As a constituent material of the surface protection film 65, for example, a silicon oxide film, a silicon nitride film, a polyimide film, an epoxy resin film, etc., have resistance to protect the element from moisture, dust, damage, etc. , particularly preferably a silicon nitride film. Although not shown in the figure, when forming the surface protection film 65 having the aforementioned silicon oxide film and silicon nitride film, it is formed in such a manner that the silicon oxide film and the silicon nitride film are sequentially formed in the same manner. After the silicon nitride film, these layers are patterned. The thickness of the surface protection film 65 is not particularly limited, and is, for example, about 500 nm or more and 2000 nm or less.

3-3 Cavity Formation Process

Next, by removing part of the sacrificial layers 41 and 42 , as shown in FIG. 8( a ), a cavity S (cavity) is formed between the insulating film 23 and the cover layer 641 . Thus, interlayer insulating films 61 and 63 are formed.

The formation of the hollow portion S is performed by removing a part of the sacrificial layers 41 , 42 by etching through the plurality of pores 642 formed in the cover layer 641 . Here, when wet etching is used as the etching, an etchant such as hydrofluoric acid or buffered hydrofluoric acid is supplied from the plurality of pores 642, and when dry etching is used, an etching solution such as hydrofluoric acid is supplied from the plurality of pores 642. 642 supplies etching gas such as hydrofluoric acid gas. When performing such etching, the insulating film 23 functions as an etching stopper layer. In addition, since the insulating film 23 has resistance to the etching solution, it also has the function of protecting the structural parts (such as the insulating film 22, the piezoresistive element 5, the wiring 214, etc.) on the lower side with respect to the insulating film 23 from the etching solution. ) function.

3-4 Sealing process

Next, as shown in FIG. 8(b), on the cover layer 641, a silicon oxide film, a silicon nitride film, a metal layer such as Al, Cu, W, Ti, TiN, etc. are formed by sputtering, CVD, or the like. The sealing layer 66 made of a film or the like is used to seal the pores 642 . As a result, the hollow part S is sealed by the sealing layer 66, and the laminated structure 6 is obtained.

Here, the thickness of the sealing layer 66 is not particularly limited, and is, for example, about 1000 nm to 5000 nm.

[4] Step of forming the diaphragm portion 20

Next, after grinding the lower surface of the silicon layer 211 as necessary, a part of the lower surface (one surface side) of the silicon layer 211 is removed (processed) by etching, thereby as shown in FIG. 8( c ). , forming the concave portion 24 . Thus, the diaphragm portion 20 is formed.

Here, when a part of the lower surface of the silicon layer 211 is removed, the silicon oxide layer 212 functions as an etching stopper layer. Accordingly, the thickness of the diaphragm portion 20 can be specified with high accuracy.

In addition, as a method of removing a part of the lower surface of the silicon layer 211 , dry etching or wet etching may be used.

Through the above steps, the pressure sensor element 1 can be manufactured.

According to the manufacturing method of the pressure sensor element 1 described above, in the obtained pressure sensor element 1, even if the diaphragm portion 20 is provided extremely thin, the resistance region 51 can be deviated to the vicinity of the surface of the diaphragm portion 20, and the The detection accuracy of the piezoelectric resistance element 5 is excellent. In addition, in the obtained pressure sensor element 1 , since the resistance region 51 is covered and buried with the cover layer 213 a, it is possible to reduce the mixing of noise into the resistance region 51 . Thereby, miniaturization and high precision of the obtained pressure sensor element 1 can be achieved.

second embodiment

9 is a cross-sectional view showing a pressure sensor element according to a second embodiment of the present invention.

The pressure sensor element of the present embodiment is the same as that of the first embodiment described above except for the difference in the structure (arrangement) of the pressure reference chamber.

In addition, in the following description, regarding the second embodiment, differences from the above-described embodiment will be mainly described, and descriptions of the same items will be omitted. In addition, in FIG. 9, the same code|symbol is attached|subjected to the structure similar to embodiment mentioned above.

In a pressure sensor element 1A shown in FIG. 9 , a substrate 3 in which a cavity S1 (pressure reference chamber) is formed together with a substrate 2 is provided instead of the laminated structure 6 of the first embodiment. Here, the substrate 3 closes the opening of the substrate 2 and is bonded to the lower surface of the substrate 2 (the surface of the silicon layer 211 ). In this way, the hollow portion S1 serving as the pressure reference chamber is formed by hermetically sealing the concave portion 24 with the substrate 3 . In addition, the substrate 3 is not particularly limited as long as the cavity S1 functioning as a pressure reference chamber can be formed, and for example, a silicon substrate, a glass substrate, a ceramic substrate, or the like can be used. In addition, the substrate 3 is sufficiently thick with respect to the diaphragm portion 20 so that the portion of the substrate 3 facing the diaphragm portion 20 across the hollow portion S1 is not deformed by the differential pressure.

Here, in the present embodiment, as described above, the hollow portion S1 functioning as the pressure reference chamber is provided on the side of the silicon layer 211 of the substrate 2, so the side of the diaphragm portion 20 opposite to the hollow portion S1 is The surface becomes the pressure receiving surface 25A.

In addition, in FIG. 9, although the illustration of the circuit part is omitted, the same circuit part as the semiconductor circuit 9 of the first embodiment described above may be provided, and the circuit part may be provided outside the pressure sensor element 1A. .

According to the second embodiment described above, as in the first embodiment, the diaphragm portion 20 can be provided extremely thin, and the resistance region 51 can be shifted toward the vicinity of the surface of the diaphragm portion 20, and the piezoresistive element can be made The detection accuracy of 5 is relatively excellent. In addition, since the resistive region 51 is buried by being covered with the cover layer 213 a, it is possible to reduce the mixing of noise into the resistive region 51 . Accordingly, it is possible to achieve downsizing and high precision of the pressure sensor element 1A.

2. Pressure sensor

Next, a pressure sensor including the pressure sensor element of the present invention (pressure sensor of the present invention) will be described. Fig. 10 is a cross-sectional view showing an example of the pressure sensor of the present invention.

As shown in FIG. 10 , the pressure sensor 100 of the present invention includes: a pressure sensor element 1; a housing 101 for accommodating the pressure sensor element 1; and a calculation unit 102 for calculating a signal obtained from the pressure sensor element 1 into pressure data . The pressure sensor element 1 is electrically connected to the computing unit 102 via wiring 103 .

The pressure sensor element 1 is fixed inside the housing 101 by a fixing unit not shown. In addition, the housing 101 has a through hole 104 for communicating the diaphragm portion 20 of the pressure sensor element 1 with, for example, the atmosphere (outside of the housing 101 ).

According to such a pressure sensor 100 , the diaphragm portion 20 receives pressure through the through hole 104 . The signal output from the pressure sensor element 1 due to this pressure is sent to the calculation unit 102 via the wiring 103, and the pressure data is calculated. The calculated pressure data can be displayed via an unillustrated display unit (for example, a display of a personal computer, etc.).

3. Altimeter

Next, an example of an altimeter including the pressure sensor element of the present invention (altimeter of the present invention) will be described. Fig. 11 is a perspective view showing an example of the altimeter of the present invention.

The altimeter 200 can be worn on the wrist like a watch. In addition, the pressure sensor element 1 (pressure sensor 100 ) is mounted inside the altimeter 200 , and the altitude of the location or the atmospheric pressure of the location can be displayed on the display unit 201 .

In addition, various information such as the current time, the user's heart rate, and weather can be displayed on the display unit 201 .

4. Electronic equipment

Next, a navigation system to which an electronic device including the pressure sensor element of the present invention is applied will be described. Fig. 12 is a front view showing an example of the electronic device of the present invention.

The navigation system 300 includes: map information not shown in the figure; a position information acquisition unit that acquires position information from GPS (Global Positioning System: Global Positioning System); an autonomous navigation unit based on gyro sensor, acceleration sensor, and vehicle speed data; and a pressure sensor element. 1. A display unit 301 that displays predetermined position information or travel route information.

According to this navigation system, not only positional information but also altitude information can be acquired. For example, when driving on an elevated road whose location information indicates approximately the same position as a general road, if there is no altitude information, it is impossible to determine whether to drive on a general road or an elevated road through the navigation system, thereby The general road information is provided to the user as priority information. Therefore, in the navigation system 300 according to the present embodiment, height information can be obtained through the pressure sensor element 1, thereby detecting a change in height due to entering an elevated road from a general road, and estimating the driving state of the elevated road. The following navigation information is provided to the user.

In addition, the display unit 301 has a structure capable of reducing the size and thickness, such as a liquid crystal panel display or an organic EL (Organic Electro-Luminescence: organic electroluminescence) display.

In addition, electronic equipment equipped with the pressure sensor element of the present invention is not limited to the above-mentioned equipment, for example, it can be applied to personal computers, mobile phones, medical equipment (such as electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring equipment, ultrasonic diagnostic equipment, etc.) Devices, electronic endoscopes), various measuring equipment, measuring instruments (such as measuring instruments for vehicles, aircraft, and ships), flight simulators, etc.

5. Moving body

Next, a moving body to which the pressure sensor element of the present invention is applied (moving body of the present invention) will be described. Fig. 13 is a perspective view showing an example of the moving body of the present invention.

As shown in FIG. 13 , the mobile body 400 has a vehicle body 401 and four wheels 402 , and is configured to rotate the wheels 402 by a power source (engine) not shown provided in the vehicle body 401 . A navigation system 300 (pressure sensor element 1 ) is built in such a mobile body 400 .

As mentioned above, although the pressure sensor element, the pressure sensor, the altimeter, the electronic device, and the moving body of the present invention have been described based on the illustrated embodiments, the present invention is not limited thereto, and the structures of the respective parts can be replaced with those having the same structure. Arbitrary structure of functions. In addition, other arbitrary structures may be added.

In addition, although the number of piezoresistive elements (functional elements) provided in one diaphragm portion was described as an example of four in the above-mentioned embodiment, it is not limited thereto. For example, , may be more than one and less than three, or may be more than five. In addition, the arrangement and shape of the piezoresistive elements are not limited to the above-mentioned embodiments, and for example, the piezoresistor elements may be arranged at the center of the diaphragm in the above-mentioned embodiments.

Symbol Description

1: pressure sensor element; 1A: pressure sensor element; 2: substrate; 3: substrate; 5: piezoresistive element; 5a: piezoresistive element; 5b: piezoresistive element; 5c: piezoresistive element; Piezoelectric resistance element; 6: laminated structure; 9: semiconductor circuit; 20: diaphragm part; 21: semiconductor substrate; 22: insulating film; 23: insulating film; 24: concave part; 25: pressure receiving surface; 25A: receiving Pressure surface; 41: sacrificial layer; 42: sacrificial layer; 51: resistance area; 51a: resistance area; 51b: resistance area; 51c: resistance area; 51d: resistance area; 61: interlayer insulating film; 62: wiring layer ;63: interlayer insulation film; 64: wiring layer; 65: surface protection film; 66: sealing layer; 67: MOS transistor; 100: pressure sensor; 101: frame; 102: computing unit; 103: wiring; 104: through hole; 200: altimeter; 201: display part; 211: silicon layer; 212: silicon oxide layer; 213: silicon layer; 213a: cover layer; 214: wiring; 214a: wiring; 214b: wiring; 214c: wiring; 214d: wiring; 300: navigation system; 301: display unit; 400: moving body; 401: vehicle body; 402: wheel; 641: covering layer; 642: pores; 671: grid electrode; L: distance; L ₁ : distance; P: pressure; t ₁ : thickness; t ₂ : thickness; S: cavity; S1: cavity; w: width.

Claims (15)

1. A method for manufacturing a resistance element, comprising: a step of preparing a substrate having a silicon layer having an n-type or p-type region; the process of forming a resistive region by doping said region with impurities; heat-treating the resistance region by any one of rapid thermal annealing, flash lamp annealing, and excimer laser annealing; A process of forming a capping layer by epitaxially growing silicon on the resistance region. 2. The manufacturing method of the resistance element as claimed in claim 1, wherein, In the step of forming the capping layer, the epitaxial growth is performed using disilane gas. 3. The manufacturing method of the resistance element as claimed in claim 1 or 2, wherein, In the step of performing the heat treatment, the thickness of the resistance region after the heat treatment is within a range of 0.1 μm to 2.0 μm. 4. The manufacturing method of the resistance element according to any one of claims 1 to 3, wherein, In the step of forming the covering layer, the thickness of the covering layer is in the range of 0.05 μm or more and 0.4 μm or less. 5. A method for manufacturing a pressure sensor element, comprising: A process of forming a resistance element using the method for manufacturing a resistance element according to any one of claims 1 to 4; A step of forming a diaphragm portion provided with the resistor element by etching one surface side of the substrate. 6. A pressure sensor element, characterized in that, With diaphragm part, The diaphragm part has: silicon layer; a resistive element having a resistive region containing carriers within said silicon layer and generating an electrical signal corresponding to deformation; a cover layer on the resistive area, The thickness of the resistance region is within the range of 5% to 30% of the thickness of the diaphragm portion, A distance between the cover layer-side surface of the diaphragm portion and the peak position of the carrier concentration of the resistance region is within a range of 2% to 40% of the thickness of the diaphragm portion. 7. The pressure sensor element of claim 6, wherein: A pressure reference chamber provided on one side of the covering layer is provided. 8. A pressure sensor element as claimed in claim 6 or 7, wherein, The thickness of the diaphragm part is in the range of 0.5 μm or more and 15 μm or less. 9. A pressure sensor element as claimed in any one of claims 6 to 8 wherein, The thickness of the resistance region is in the range of 0.1 μm or more and 2.0 μm or less. 10. A pressure sensor element as claimed in any one of claims 6 to 9 wherein, A distance between the cover layer-side surface of the diaphragm portion and the peak position of the carrier concentration of the resistance region is within a range of 0.05 μm to 0.4 μm. 11. A pressure sensor element as claimed in any one of claims 6 to 10 wherein, A substrate having the diaphragm portion and the circuit portion is provided. 12. A pressure sensor, characterized in that, A pressure sensor element according to any one of claims 6 to 11 is provided. 13. An altimeter, characterized in that, A pressure sensor element according to any one of claims 6 to 11 is provided. 14. An electronic device characterized in that, A pressure sensor element according to any one of claims 6 to 11 is provided. 15. A mobile body characterized in that, A pressure sensor element according to any one of claims 6 to 11 is provided.