JPH0875517A - Semiconductor microsensor and manufacture thereof - Google Patents

Abstract

PURPOSE: To obtain a semiconductor microsensor having high detection sensitivity and response time constant and strong against destruction due to disturbance. CONSTITUTION: The semiconductor microsensor comprises a semiconductor substrate 11 having a first recess 13 made in one major surface 11a having (100) face in the <100> direction, an interlayer structure 21 provided on one major surface 11a with one or more of detection elements 24 being formed at a part corresponding to the first recess 13, and an upper structure 31 provided on the interlayer structure 21 with a second recess 32 corresponding to the first recess 13 being made in one major surface on the interlayer structure 21 side and a plurality of through holes 33a, 33b communicating with the outside being made in the bottom face of the second recess 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor microsensor which is used for detecting a physical quantity such as a flow rate, acceleration, pressure, etc. of a fluid, has a high detection sensitivity, and is not easily destroyed by an external disturbance, and a manufacturing method thereof. It is a thing.

[0002]

2. Description of the Related Art FIG. 23 shows, for example, JP-A-63-2711.
FIG. 1 is a cross-sectional view showing a flow velocity sensor as a conventional semiconductor microsensor disclosed in Japanese Patent Publication No. 67, 67, in which 1 is a single crystal silicon substrate (hereinafter abbreviated as Si substrate) and 2 is S.
A pit (recess) having a trapezoidal cross section formed on the i substrate 1 by anisotropic etching, 3 is a silicon oxide film (SiO ₂ film) formed on the Si substrate 1 around the pit 2, and 4 is Si.
BPSG formed on the O ₂ film 3, 5 is a SiO ₂ film formed on the BPSG 4 so as to cover the pits 2, and 6 is Si
Porous silicon oxide formed in the recess 5a on the lower surface of the O ₂ film 5, 7 is a heating element formed on the SiO ₂ film 5, and 8 is S.
It is a temperature detection element formed on the iO ₂ film 5.

Next, a method of manufacturing this flow velocity sensor will be described with reference to FIG.
It will be explained based on. First, pits 2 are formed on the Si substrate 1a, and the SiO ₂ film 3 is formed on the Si substrate 1a around the pits 2.
a, a first sensor member (FIG. 3A) formed by sequentially forming BPSG 4a, a SiO ₂ film 3b is formed on a Si substrate 1b, and a porous hollow is formed in the central depression on the SiO ₂ film 3b. A second sensor member (FIG. 2B) in which BPSG 4b is formed around silicon oxide 6 is produced, and then BPSG 4a of the first sensor member and B of the second sensor member are formed.
The first and second sensor members are bonded to each other by bringing them into close contact with the PSG 4b and melting these BPSGs 4a and 4b at a high temperature of about 1000 ° C. (FIG. 7 (c)), and then one Si substrate 1b is attached. It is completely removed by etching, and the heating element 7 and the temperature detecting element 8 are formed on the SiO ₂ film 3b to form a flow velocity sensor.

In this flow velocity sensor, the flow velocity of the fluid is measured by detecting the heating current flowing so as to return the heating element 7 to the original temperature when the heating element 7 is cooled by the flow of the fluid. .

[0005]

Since the flow velocity sensor as the conventional semiconductor microsensor is constructed as described above, since the heating element 7 and the temperature detection element 8 are directly exposed to the fluid, a certain degree of sensitivity can be obtained. On the other hand, dust contained in the air is liable to accumulate on the elements 7 and 8, so that it is difficult to maintain the characteristics of the sensor constant for a long time. In order to avoid this, there is a problem that it is necessary to increase the film thickness of the detection portion to increase the mechanical strength by making a trade-off with a decrease in detection sensitivity.

In addition, in order to obtain a desired structure, it is necessary for the above-described flow velocity sensor to bond together a plurality of members whose surfaces are previously processed with depressions or the like. In such a process, there are problems in alignment and reliability of the bonding site, and above all, there is a problem that throughput is low and cost is high. In addition, it is necessary to raise the temperature of the member for bonding, which may adversely affect the characteristics of other functional thin films. Therefore, for example, Japanese Patent Laid-Open No. 4-343
As shown in Japanese Patent No. 023, a method of performing etching from the back surface is also proposed, but this method also has a problem in the reliability of alignment, which complicates packaging and lowers the mechanical strength of the chip. There were problems such as bringing it.

The inventions set forth in claims 1 to 13 have been made to solve the above-mentioned problems, and a semiconductor microsensor having high detection sensitivity and a small response time constant and being hardly destroyed by an external disturbance is provided. The purpose is to get.

It is an object of the invention of claim 14 or 15 to provide a method for manufacturing a semiconductor microsensor, which has a high processing accuracy, thus improving yield and reliability, and is inexpensive.

[0009]

A semiconductor microsensor according to a first aspect of the present invention is provided on a main surface having a <110> direction and a (100) plane of a semiconductor substrate, and is provided on the first main surface. An interlayer structure having one or more detection elements formed in a portion corresponding to the recess, and a first main surface provided on the interlayer structure on the side of the interlayer structure so as to face the first recess. And an upper structure having a plurality of through holes communicating with the outside formed on the bottom surface of the second recess.

According to a second aspect of the present invention, there is provided a semiconductor microsensor in which the interlayer structure is provided with a frame portion provided around the first recess and a pressure provided in the frame portion and introduced from the outside. It is provided with a pressure receiving portion for receiving, and a plurality of beam portions which are provided between both ends of the pressure receiving portion and the frame portion, and at least one of which has a piezoresistance formed.

According to a third aspect of the semiconductor microsensor of the present invention, each of the first concave portion and the second concave portion is provided with a protruding portion for supporting the pressure receiving portion within the elastic limit of the pressure receiving portion. .

According to a fourth aspect of the present invention, there is provided a semiconductor microsensor in which the interlayer structure is formed in a portion corresponding to the first concave portion and which receives a pressure introduced from the outside, and a pressure receiving portion which supports the pressure receiving portion. Beam portion and a first electrode formed in the pressure receiving portion, wherein the semiconductor substrate has a second electrode in the first recess and the upper structure has a third electrode in the second recess. Each is equipped.

According to a fifth aspect of the present invention, there is provided a semiconductor microsensor in which the interlayer structure is provided with a frame portion provided around the first recess, and at least one end of the frame portion is provided in the frame portion. And a heating element that is formed on the protrusion and detects the flow rate from the change in resistance value due to the flow of the surrounding fluid.

According to a sixth aspect of the present invention, a semiconductor microsensor is provided with a heat sensitive element on both sides of the heat generating element for detecting a temperature change caused by a fluid flow as a change in resistance value.

According to a seventh aspect of the present invention, a semiconductor microsensor introduces a pressure difference due to a Karman vortex generated from a vortex generating section provided in a flow path into a pressure receiving section via a pressure guiding tube.

In a semiconductor microsensor according to an eighth aspect of the present invention, the interlayer structure is provided with a frame portion provided around the first concave portion, and at least one end portion is provided in the frame portion in parallel with each other. A plurality of protrusions connected to the frame, a heat sensitive element formed on one of the protrusions for detecting the temperature of the surrounding fluid, and a temperature higher than the temperature of the fluid formed on the other protrusion by a predetermined temperature. And a heating element that generates heat.

According to a ninth aspect of the present invention, there is provided a semiconductor microsensor in which the interlayer structure is provided with a frame portion provided around the first concave portion, and at least one end portion is provided in the frame portion in parallel with each other. A plurality of protrusions connected to the frame, a first thermosensitive element formed on one of the protrusions for detecting the temperature of the surrounding fluid, and a predetermined temperature higher than the temperature of the fluid formed on the other protrusion. It is provided with a heating element that generates heat so that the temperature rises and a second thermosensitive element that detects the temperature of the heating element.

A semiconductor microsensor according to a tenth aspect of the present invention is a semiconductor microsensor, wherein the interlayer structure has a mass portion formed in a portion corresponding to the first recess, a support portion that supports the mass portion, and the support. And at least one piezoresistor which is formed in the section and detects the magnitude of the acceleration received by the mass section as a change in the resistance value.

In a semiconductor microsensor according to an eleventh aspect of the present invention, the interlayer structure has a mass portion formed in a portion corresponding to the first recess, and a first mass portion formed in the mass portion.
And the supporting portion for supporting the mass portion, and the second electrode is provided in the first recess and the third electrode is provided in the second recess.

A semiconductor microsensor according to a twelfth aspect of the present invention is such that the supporting portion has a cantilever structure including one or more beam portions.

A semiconductor microsensor according to a thirteenth aspect of the present invention is such that the supporting portion is composed of at least two beam portions provided at both ends of the mass portion.

According to a fourteenth aspect of the present invention, there is provided a method for manufacturing a semiconductor microsensor, wherein a first sacrificial layer is provided at a predetermined position on a main surface having a <110> direction and a (100) plane of a semiconductor substrate. A first structural layer is provided on the central portion of the sacrificial layer and the one main surface, a detection element is provided at a predetermined position on the first structural layer, and a second structural layer is sequentially provided on the first structural layer and the detection element. An interlayer structure forming step of forming, a second sacrificial layer including the first and second structural layers on the first sacrificial layer, and the second sacrificial layer.
A third structural layer on the sacrificial layer and the second structural layer,
Upper structure forming step of sequentially forming a plurality of through holes at predetermined positions of the structure layer, a sacrificial layer removing step of removing the first and second sacrificial layers, and a predetermined etching of the semiconductor substrate by anisotropic etching. And a recess forming step of forming the first recess at the position.

According to a fifteenth aspect of the present invention, in the method of manufacturing a semiconductor microsensor, in the step of forming the interlayer structure, a high-concentration impurity-added layer is formed on a portion of the main surface of the semiconductor substrate where a protrusion is to be formed. And the step of forming a groove in the portion of the second sacrificial layer where the protrusion is to be formed in the upper structure forming step.

[0024]

In the semiconductor microsensor according to the invention of claim 1, since the interlayer structure having the detection element is provided between the semiconductor substrate and the upper structure, the detection element is directly covered with the upper structure. It is not exposed to external media and external disturbances, thus preventing deterioration of detection characteristics due to contamination, and maintaining high detection sensitivity and small response time constant. It is also hard to be destroyed without being directly affected by external disturbances. As a result, by increasing the mechanical strength of the support portion to withstand external disturbances in the related art, the detection sensitivity, which has been impaired as a trade-off, is not reduced, and high detection sensitivity and a wide dynamic range are maintained.

According to another aspect of the present invention, there is provided a semiconductor microsensor, wherein a pressure receiving portion provided in a frame portion for receiving a pressure introduced from the outside, and at least one provided between both ends of the pressure receiving portion and the frame portion. Since the plurality of beam portions having the piezoresistors are provided, a twist about the beam portions generated in the plurality of beam portions when the pressure receiving portion receives pressure is detected as a change in the resistance value of the piezoresistance. By doing so, the pressure received by the pressure receiving portion is detected with high sensitivity.

According to a third aspect of the present invention, in the semiconductor microsensor, the first concave portion and the second concave portion are each provided with a protruding portion for supporting the pressure receiving portion within an elastic limit of the pressure receiving portion. Damage due to excessive amplitude of pressure receiving part,
Deflection of the plurality of beam portions in the thickness direction and blurring of the beam portions as a rotation axis are prevented, and twisting of the pressure receiving portion around the beam portions is detected in a more stable state.

A semiconductor microsensor according to a fourth aspect of the present invention includes a first electrode in the pressure receiving portion, a second electrode in the first recess, and a third electrode in the second recess. By detecting the twist of the beam portion as the difference between the capacitance between the first electrode and the second electrode and the capacitance between the first electrode and the third electrode, the pressure receiving portion Detects the pressure received with high sensitivity.

In the semiconductor microsensor according to the invention of claim 5, the heating element for detecting the flow rate from the change in the resistance value due to the flow of the surrounding fluid is formed in the protruding portion.
The flow rate or flow velocity of the fluid is detected with high sensitivity.

In the semiconductor microsensor according to the invention of claim 6, the heat sensitive element for detecting the temperature change caused by the flow of the fluid as the change of the resistance value is provided on both sides of the heat generating element. When the fluid flows toward the heat-sensitive element, the degree of transfer of the amount of heat generated by the heat-generating element differs between the upstream side and the downstream side of the flow, and a temperature difference occurs between these heat-sensitive elements. The temperature difference between the heat sensitive elements is detected as a difference in resistance value between the heat sensitive elements, and the flow rate of the fluid is detected with high sensitivity based on the difference in resistance value.

In the semiconductor microsensor according to the invention of claim 7, since the pressure receiving portion receives the periodically varying pressure difference generated in the flow passage by the Karman vortex generated by the vortex generating portion through the pressure guiding tube, the beam portion It is possible to detect the flow velocity of the fluid flowing through the flow path with high sensitivity by periodically twisting with respect to the rotation axis and detecting this twist with piezo resistance.

According to another aspect of the semiconductor microsensor of the present invention, a heat-sensitive element formed on one of the protrusions for detecting the temperature of the surrounding fluid, and a temperature higher than the temperature of the fluid formed on the other of the protrusions by a predetermined temperature. By providing the heating element that generates heat, the heating element is cooled by the flow of the fluid, and a heating current for returning the temperature of the heating element to the original temperature flows in the heating element. By detecting this heating current, the flow rate of the fluid can be detected with high sensitivity.

According to a ninth aspect of the present invention, in a semiconductor microsensor, a first heat sensitive element formed on one of the protrusions for detecting the temperature of the surrounding fluid and a temperature of the fluid formed on the other of the protrusions have a predetermined value. By providing the heating element that generates heat so that the temperature rises and the second thermosensitive element that detects the temperature of the heating element, the heating element is cooled by the flow of the fluid, and based on the temperature of the heating element. A heating current for returning flows to the heating element. By detecting this heating current, the flow rate of the fluid can be detected with high sensitivity.

According to a tenth aspect of the invention, in a semiconductor microsensor, a mass part, a support part for supporting the mass part, and an amount of acceleration formed on the mass part and received by the mass part are detected as a change in resistance value. By providing at least one piezoresistor, the mass part is displaced when acceleration is applied to the mass part, and the support part is bent due to the displacement, and the flexure is regarded as a change in the resistance value of the piezoresistor. To detect. Thereby, the acceleration acting on the mass portion is detected with high sensitivity.

According to the eleventh aspect of the invention, in the semiconductor microsensor, the mass part is provided with the first electrode, the first recess is provided with the second electrode, and the second recess is provided with the third electrode. The magnitude of the acceleration acting on is detected as the difference between the capacitance between the first electrode and the second electrode and the capacitance between the first electrode and the third electrode. Thereby, the acceleration acting on the mass portion is detected with high sensitivity.

According to the twelfth aspect of the present invention, in the semiconductor microsensor, the supporting portion has a cantilever structure composed of one or more beam portions, so that when the mass portion is subjected to acceleration, the mass portion causes the beam portion to move. As a fulcrum, it is displaced in proportion to the magnitude of the acceleration. Therefore, the piezo resistance formed on the beam portion is distorted, and the magnitude of the acceleration can be obtained from the amount of change in the resistance value. Thereby, the acceleration acting on the mass portion is detected with higher sensitivity.

According to a thirteenth aspect of the present invention, in the semiconductor microsensor, the supporting portion is composed of at least two beam portions provided at both ends of the mass portion, and when acceleration acts on the mass portion, The mass portion is displaced in proportion to the magnitude of the acceleration, the piezoresistors formed on the plurality of beam portions are also distorted, and the magnitude of the acceleration is determined from the amount of change in these resistance values. Thereby, the acceleration acting on the mass portion is detected accurately and with high accuracy.

According to a fourteenth aspect of the present invention, in the method of manufacturing a semiconductor microsensor, an interlayer structure in which each layer including the first sacrificial layer is sequentially formed on a main surface having a <110> direction and a (100) plane of a semiconductor substrate. By providing the body forming step, the upper structure forming step of forming each layer including the second sacrificial layer, and the sacrificial layer removing step, the interlayer structure on which the detection element is formed depends on the crystal orientation of the semiconductor substrate. The shape is not limited, and the degree of freedom in design is increased, and the optimum shape can be selected. Further, the shape of the upper structure is similarly optimized by providing the second sacrificial layer.

Further, by providing the recess forming step of forming the first recess in the semiconductor substrate by anisotropic etching, an interlayer structure physically separated from both the semiconductor substrate and the upper structure can be obtained. It will be possible. Therefore, a pasting process for pasting a plurality of members, which has been used conventionally, becomes unnecessary, and the problems relating to the strength and reliability of the joining site and the influence of the joining process on other functional thin films are eliminated. Further, by controlling the thickness of the sacrificial layer and the anisotropic etching time, the physical gap between the interlayer structure and the upper structure or the substrate is arbitrarily adjusted.

According to the fifteenth aspect of the present invention, in the method for manufacturing a semiconductor microsensor, since the high-concentration impurity-added layer is formed on the one main surface, the added layer is not etched during anisotropic etching and the protrusions are formed. Will remain in the first recess. As a result, an optimally shaped protrusion is formed in the first recess. In addition, since the groove is formed in the second sacrificial layer, the third structural layer formed in the groove is not removed during the sacrificial layer removing step and remains on the third structural layer as a protrusion. It will be. As a result, an optimally shaped protrusion is formed in the second recess.

[0040]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 11 is the <110> direction and (10
A Si substrate (semiconductor substrate) 21 having a pit (first concave portion) 13 formed in a surface (one main surface) 11a having a (0) plane and a support shaft (projection portion) 14 formed in the pit 13 is An anchor portion (frame portion) 22 provided on the surface 11a and provided around the pit 13, and a pressure receiving portion 23 provided in the anchor portion 22 and receiving a pressure introduced from the outside.
And torsion bars (beam portions) 25a and 25b provided between both ends of the pressure receiving portion 23 and the anchor portion 22 and having a piezoresistor 24 formed on one side thereof, and the wiring 26 and the bonding pad 27 formed on the anchor portion 22. An inter-layer structure 31 including: a concave portion (second concave portion) 32 is formed on the surface on the side of the inter-layer structure 21, and through holes 33a and 33b communicating with the outside and a support shaft (projection) are formed on the bottom surface of the concave portion 32. Part) 34 is an upper structure.

In this semiconductor microsensor, as shown in FIGS. 2 and 3, the recess 32 formed on the lower side of the upper structure 31 and the pit 13 formed on the Si substrate 11 cause the vibration of the pressure receiving portion 23. Providing a reasonable clearance 41.
The upper structure 31 and the Si substrate 11 also serve as a stopper that prevents damage to the pressure receiving portion 23 due to excessive amplitude. The support shaft 34 formed on the bottom surface of the recess 32 of the upper structure 31 and the support shaft 14 formed on the bottom surface of the pit 13 prevent the torsion bars 25a and 25b from bending in the chip thickness direction, and the torsion bar of the pressure receiving portion 23. 25a,
Stabilizes the twist around 25b.

FIG. 4 is a sectional view showing a Karman vortex flowmeter using this semiconductor microsensor, and FIG. 5 is a sectional view taken along the line BB of FIG. In FIGS. 4 and 5, 51 is a flow path through which a fluid flows, 52 is a vortex generator (vortex generator) provided in the flow path 51, and 53 is a pair of pressure guides provided downstream of the vortex generator 52. A pressure guiding tube having holes 53a and 53b, and 54 is a sensor chip (semiconductor microsensor) provided at the end of the pressure guiding tube 53.

In this Karman vortex flowmeter, when the fluid 55 flows in the flow passage 51, the Karman vortex train 56 is generated by the vortex generator 52. The periodically varying pressure difference generated by the Karman vortex train 56 passes through the pressure guiding holes 53a and 53b provided immediately after the vortex generator 52 and passes through the sensor chip 54.
It is pressured to the inside. The pressure receiving portion 23 provided in the interlayer structure 21 receives the pressure difference thus induced, and is twisted periodically with the torsion bars 25a and 25b as rotation axes. By detecting the frequency of this twist with the piezoresistor 24 formed in the torsion bar 25b, the flow velocity of the fluid flowing through the flow path 51 can be measured. The detected signal is taken out from the bonding pad 27 formed at the end of the wiring 26.

Example 2. 6 to 8 are process diagrams showing a method of manufacturing a semiconductor microsensor according to another embodiment of the present invention. FIG. 6 is a cross section taken along the line AA of FIG. 1, and FIG. 7 is a line CC of FIG. The cross section along the line and FIG. 8 correspond to the cross section along the line D-D in FIG. 1, respectively.

First, on the surface 11a of the Si substrate 11, a metal film of, for example, Ti, Mn, Ni, Zn, etc.
A first sacrificial layer 61 that is selectively etchable with an acid such as is deposited. Preferably, the contour is shaped into a rectangle having sides in the <110> direction, and finally the Si substrate 11
The outer shape of the pit 13 formed in the above is defined. Next, first structural layers 62a and 62b such as a silicon nitride film are deposited on the first sacrificial layer 61 and the remaining Si substrate 11. Next, in order to form a movable portion, the first sacrifice layer 61 is shaped so as to be surrounded by portions other than the first structural layer 62a serving as the anchor portion. Then, the piezoresistor 24 is formed on the first structure layer 62b at the portion to be the torsion bar 25b, and the piezoresistor 24 is formed on the second structure layer 63 so as to be included in the first structure layer 62b. By depositing a silicon nitride film formed on the first structure layers 62a and 62b and the second structure layers 62a and 62b.
The inter-layer structure 21 including the structure layer 63 and the piezoresistor 24 is formed. The second structure layer 63 can protect the piezoresistor 24 from being dissolved by a sacrifice layer etching or an anisotropic etching performed later. Next, a second sacrificial layer 64, which is a metal film of Ti, Mn, Ni, Zn, or the like, and which includes the movable portion of the interlayer structure 21 with the first sacrificial layer 61, is deposited and shaped. Then, a silicon nitride film to be the third structural layer 65 is deposited on the entire surface of the second structural layer 63 and the second sacrificial layer 64 (FIG. 6).
(A), FIG. 7 (a), FIG. 8 (a)).

After that, the second sacrificial layer 64 of Ti, Mn,
A through-hole 66 reaching a metal film of Ni, Zn, Al or the like is formed (FIG. 6 (b), FIG. 7 (b), FIG. 8 (b)). The through hole 66 is an inlet for the etching solution and also a pressure guide port for guiding the pressure generated by the Karman vortex street 56 to the pressure receiving portion 23 at the center of the interlayer structure 21.

Through this through hole 66, Ti, Mn, N
The first and second sacrificial layers 6 are formed by an etching solution that selectively dissolves only metal films such as i, Zn, and Al, for example, concentrated hydrochloric acid.
1 and 64 are removed to separate the movable portion of the interlayer structure 21 from the Si substrate 11, and the etching solution inflow channel 67 is formed in the next step (FIGS. 6C and 7C).
FIG. 8 (c)).

An alkaline etchant for anisotropically etching Si such as KOH is injected through the etchant inflow channel 67 to form pits 13 in the Si substrate 11 (FIGS. 6 (d), 7 (d), and 7 (d)). 8 (d)). By taking the above steps, it is possible to obtain a semiconductor microsensor having a desired structure only by processing from the substrate surface without bonding a plurality of members.

Example 3. FIG. 9 is a sectional view showing a semiconductor microsensor according to another embodiment of the present invention. The sensor chip 54 is used in a Karman vortex flowmeter of a type in which a flow caused by a pressure difference is detected by the heating element 7.
The heating element 7 is cooled by the flow 71 of the fluid in the chip caused by the pressure difference, and its resistance value changes.
By detecting this resistance value, the flow velocity of the fluid flowing through the flow path 51 can be measured. Typical dimensions of the bridge are 200-300 microns long, 20-3 wide.
It is 0 micron and the thickness is 5 microns or less. In the present embodiment, the portion of the interlayer structure 21 where the detection element is formed is shown as a bridge bridging the gap 41, but it goes without saying that it may be a cantilever structure with a cantilever. Further, platinum is preferably used as the heating element 7.

Example 4. FIG. 10 is a cross-sectional view showing a thermal type flow meter using a semiconductor microsensor according to another embodiment of the present invention, in which 81 is provided with a sensor chip 54 inside, and an inlet 82, an outlet 83 and a sensor chip Through hole 54
The housing has a thin tube 84 communicating with a and 54b.

FIG. 11 is a sectional view showing a state in which the semiconductor microsensor of this embodiment is installed in the venturi portion 51a of the flow channel 51. 85 and 86 in the flow path 51 are a high pressure part and a low pressure part, respectively. At this time, since there is a pressure difference between the inflow port 82 and the outflow port 83, a flow is generated in the thin tube 84 from the inflow port 82 through the pressure receiving portion 23 toward the outflow port 83. The pressure difference between the inflow port 82 and the outflow port 83, and thus the flow velocity and flow rate of the fluid flowing through the flow path 51, are proportional to the flow rate passing through the pressure receiving portion 23. Therefore, the output signal from the pressure receiving portion 23 becomes an index of the flow rate of the fluid flowing through the flow path 51.

Example 5. FIG. 12 is a plan view showing an interlayer structure 91 of a sensor chip (semiconductor microsensor) used in a thermal mass flowmeter according to another embodiment of the present invention, in which 92 is supported by the anchor portion 22. The heat generating element 7 is formed on the bridge 92, and the heat sensitive elements 93a and 93b are formed on both sides of the heat generating element. In this sensor chip, the heat generating element 7 is formed on the bridge 92 so that the anchor portion 22 connected to the substrate is thermally insulated from the heat generating element 7.
Typical dimensions of the bridge 92 are 400-500 microns long, 20-50 microns wide, and 5 microns thick or less. In this embodiment, the shape of the portion where the heating element 7 is formed is a bridge shape, but a cantilever structure with a cantilever may be used.

The heating element 7 operates under constant power supply. In this case, the amount of heat transferred from the heat generating element 7 to the air is different between the upstream side and the downstream side, and the upstream side is cooled more than the downstream side. Therefore, these two heat sensitive elements 93a, A temperature difference occurs between 93b. Since this temperature difference is a function of the flow rate, the heat sensitive elements 93a, 93b
The flow rate can be calculated from the difference in the resistance values of If a slit extending in the direction perpendicular to the air flow is provided at the center of the heating element 7, the temperature difference becomes more remarkable.

Example 6. FIG. 13 is a plan view showing an interlayer structure 101 of a sensor chip (semiconductor microsensor) used in a direct heating type mass flowmeter according to another embodiment of the present invention, and FIG. 14 is a sensor chip to which this interlayer structure 101 is applied. 1
FIG. 16 is a cross-sectional view showing a state in which 02 is provided in the flow channel 51. In this embodiment, two bridges 92a and 92b are formed,
An air temperature detecting element (heat sensitive element) 8 is formed on the upstream bridge 92a, and a heating element 7 is formed on the downstream bridge 92b. The bridge 92a, 92b and the anchor portion 22 are formed.
We are aiming for heat insulation with. The detection element 8 has a known temperature characteristic of its resistance value, and is driven by a constant current to detect the fluid temperature. The temperature of the heating element 7 is controlled by an external circuit so as to be higher than the fluid temperature detected by the detection element 8 by a constant temperature. Therefore, when the heat generating element 7 is cooled by the flow 71, the amount of heat generated by the heat generating element 7 can be known by detecting the heating current flowing through the heat generating element 7 in an attempt to return the heat generating element 7 to the original temperature by an external circuit. In such a case, the heat generation amount of the heating element 7 can be regarded as equal to the heat radiation amount, and the heat radiation amount of the heating element 7 can be expressed as a function of the flow rate of the fluid. Therefore, the flow rate is measured by detecting the heating current. can do. Also in this embodiment, the shape of the portion where the detection element 8 and the heating element 7 are formed may be a cantilever structure with two cantilevers instead of a bridge.

Example 7. FIG. 15 is a plan view showing an interlayer structure 111 of a sensor chip (semiconductor microsensor) used in an indirectly heated mass flowmeter according to another embodiment of the present invention. Also in this embodiment, the bridges 92a and 92a are provided.
It is two of b. An air temperature detecting element 8 is formed on the upstream bridge 92a, a heating element 7 is formed on the downstream bridge 92b, and a heat sensitive element 93 that is close to the heating element 7 and detects the temperature thereof is formed. Various configurations can be considered for the shape and the positional relationship between the heat generating element 7 and the heat sensitive element 93 that detects the temperature thereof in order to enhance the thermal coupling. For example, both of them have a comb-like shape and are nested with each other. Further, by using the two bridges 92a and 92b, the air temperature detecting element 8 and the heating element 7 can be thermally insulated. The bridges 92a and 92b
May have a cantilever structure with a cantilever.

In this indirectly heated mass flow meter, the temperature of the heat generating element 7 is detected by the heat sensitive element 93 in the vicinity thereof. That is, since the heating element 7 and the thermosensitive element 93 are very close to each other, these temperatures can be regarded as substantially the same, and the temperature of the heating element 7 is detected by the thermosensitive element 93. Another thermally insulated bridge 92
The flow rate is detected by the same principle as that of the above-described sixth embodiment by using an external circuit that controls the temperature difference between the fluid temperature detected by another detection element 8 provided on a and the temperature of the heating element 7 to be constant. be able to.

Example 8. FIG. 16 is a plan view showing an interlayer structure 121 of a piezoresistive acceleration sensor (semiconductor microsensor) according to another embodiment of the present invention. In the drawing, 122 is arranged at the center of the gap 41, and A mass body (mass part) vibrating in the thickness direction (direction perpendicular to the paper surface in the figure), 123 is an anchor part (frame part) that cantilevers the mass body 122, and 124 is the mass body 122 and the anchor part 1.
23 is a supporting beam (supporting portion) provided between the piezoresistor 24 and the piezoresistor 24.

In this acceleration sensor, when acceleration is applied to the mass body 122, the mass body 122 is displaced in the thickness direction,
The support beam 124 is bent due to the displacement, and the bending is detected as a change in the resistance value of the piezoresistor 24. According to this acceleration sensor, the magnitude of acceleration can be obtained accurately and with high sensitivity.

In this acceleration sensor, an example in which the support structure is cantilevered and the number of support beams 124 is one is shown, but the support structure is not limited to this, and the configuration is suitable for the shape and sensitivity of the sensor. Can be taken.

Example 9. FIG. 17 is a process diagram showing a method of manufacturing a semiconductor microsensor according to another embodiment of the present invention. First, a high-concentration boron-doped layer (high-concentration impurity-added layer) that serves as a support shaft at a predetermined position on the surface 11a of the Si substrate 11.
131 is formed, and then the first sacrificial layer 61 and the first structural layer 6 are formed on the Si substrate 11 so as to cover the doped layer 131.
2. A detection element (not shown), a second structural layer 63, and a second sacrificial layer 64 are sequentially deposited (FIG. 11A). Next, a groove 132 is formed by RIE or the like at a position on the second sacrificial layer 64 where the other supporting shaft is to be formed (FIG. 8B). This groove 132 is provided in the second structural layer 6 if necessary.
The support shaft and the interlayer structure 21 may be connected to each other by leaving a depth of up to 3. Then, the third structural layer 65 is deposited on the second sacrificial layer 64 and the surrounding second structural layer 63 (FIG. 7C). After that, a through hole 66 penetrating the third structural layer 65 and reaching the second sacrificial layer 64 is formed (FIG. 7D), and the first and second through holes 66 are formed.
Of the supporting shaft 3 by selectively etching the sacrificial layers 61 and 64 of
4 and the etching liquid inflow channel 133 are formed (FIG. 7E). Finally, pits 13 are formed in the Si substrate 11 by anisotropic etching as a margin for twisting the interlayer structure 21. At this time, since the high-concentration boron-doped layer 131 is not dissolved, the support shaft 14 remains (FIG. 6 (f)). From the above,
The support shafts 14 and 34 having the optimum shape can be formed.

Example 10. FIG. 18 is a sectional view showing a semiconductor microsensor according to another embodiment of the present invention, in which the groove formed in the second sacrificial layer reaches the second structural layer 63. In this semiconductor microsensor, the pressure receiving portion 23 can be connected to the upper structure 31 via the support shaft 34.

Example 11. FIG. 19 is a sectional view showing a capacitive acceleration sensor (semiconductor microsensor) according to another embodiment of the present invention, and FIG. 20 is a plan view showing an interlayer structure 141 of the sensor. A mass body 122 that is bent in the chip thickness direction due to acceleration is formed on the interlayer structure 141, and the surface of the mass body 122 is doped with high-concentration impurities.
42 is formed and used as a movable electrode. Mass 1
The support method of 22 is cantilevered by the support beam 124, or supported by both ends. Further, the number of support beams 124 can be arbitrarily set according to the required sensitivity and measurement range. On the surface of the Si substrate 11 facing the movable electrode 142, a high-concentration impurity-doped layer to be the fixed electrode 143 is formed. By doping impurities with a high concentration, it can be used as the electrode 143, and at the same time, it becomes insoluble in an alkaline etching solution used in a later step. The portion of the upper structure 31 facing the movable electrode 142 is formed of a polycrystalline silicon layer 144 that is highly doped with impurities and is used as the fixed electrode 144. When a polycrystalline silicon film is used for the upper structure and the interlayer structure 141 as in this embodiment, a silicon oxide film that can be selectively etched by hydrofluoric acid is used as the first and second sacrificial layers.

According to this capacitance type acceleration sensor, the magnitude of the acceleration acting on the mass body 122 is determined by the capacitance between the movable electrode 142 and the fixed electrode 143 and the capacitance between the movable electrode 142 and the fixed electrode 144. The acceleration can be detected with high sensitivity because it is detected as a differential capacitance which is the difference between

Example 12 FIG. 21 is a sectional view showing a sensor chip (semiconductor microsensor) used in a capacitive Karman vortex flowmeter of another embodiment of the present invention, and FIG. 22 is a plan view showing an interlayer structure 151 of the sensor chip. In this sensor chip, the high-concentration impurity-doped layer 143 formed on the surface 11a of the Si substrate 11 and the high-concentration impurity-doped polycrystalline silicon layer 144 formed on the upper structure.
Are used as fixed electrodes. Further, the pressure receiving portion 23 of the interlayer structure is also composed of the high-concentration impurity-doped polycrystalline silicon layer 142, and is used as a movable electrode that can be twisted around the support beam 124. As the measurement principle, the Karman vortex frequency is measured by detecting the differential capacitance between the capacitance between the fixed electrode 143 and the movable electrode 142 and the capacitance between the fixed electrode 144 and the movable electrode 142. The flow velocity of the main stream flowing through the passage can be measured.

[0065]

As described above, according to the first aspect of the present invention, the portion corresponding to the first recess is provided on the main surface of the semiconductor substrate having the <110> direction and the (100) plane. An interlayer structure having one or more detection elements formed thereon, and a second concave portion provided on the interlayer structure and facing the first concave portion is formed on one main surface of the interlayer structure on the side of the interlayer structure. Since the upper structure having the plurality of through holes communicating with the outside is formed on the bottom surface of the second recess, the upper structure has a high detection sensitivity and a small response time constant, and is free from external disturbance. There is an effect that it is possible to provide a semiconductor microsensor that is not easily destroyed. Further, since the detection element and the interlayer structure having a fine structure are configured to be covered by the substrate and the upper structure, the substrate and the upper structure are prevented from adhering dust to the detection element and the interlayer structure is excessively large. It plays the role of a stopper for the amplitude and can significantly reduce the characteristic fluctuation due to contamination and the damage due to external disturbance. Therefore, conventionally, in order to increase the strength, the film thickness and width of the supporting portion must be increased to lower the thermal and physical insulation with the substrate, and as a result, the detection sensitivity must be reduced by trade-off. There is an effect that can be solved.

According to the second aspect of the present invention, the interlayer structure includes a frame portion provided around the first recess, and a pressure receiving portion provided in the frame portion and receiving a pressure introduced from the outside. And a plurality of beam portions provided between both ends of the pressure receiving portion and the frame portion and having piezoresistors formed on at least one side thereof, the pressure received by the pressure receiving portion can be detected with high sensitivity. There is an effect that can be.

According to the third aspect of the present invention, the first concave portion and the second concave portion are each provided with the protrusions for supporting the pressure receiving portion within the elastic limit of the pressure receiving portion. It is possible to prevent damage due to excessive amplitude of the pressure receiving portion, bending of the beam portion in the thickness direction and blurring of the beam portion, and it is possible to detect twist in which the beam portion of the pressure receiving portion is the rotation axis in a more stable state. There is an effect that can be done.

According to the invention of claim 4, a pressure receiving portion which is formed in a portion of the interlayer structure corresponding to the first concave portion and receives a pressure introduced from the outside, and a beam portion which supports the pressure receiving portion. And a first electrode formed on the pressure receiving portion,
The semiconductor substrate includes a second electrode in the first recess, and the upper structure includes a third electrode in the second recess. The capacitance between the first electrode and the second electrode and the capacitance between the first electrode and the second electrode. Since the twist of the beam portion is detected by measuring the capacitance between the first electrode and the third electrode, the pressure received by the pressure receiving portion is detected as a differential capacitance, so that high sensitivity is achieved. There is an effect that can be detected.

According to the fifth aspect of the present invention, it is provided with the projecting part connected to the frame part and the heating element formed on the projecting part for detecting the flow rate from the change in resistance value due to the flow of the surrounding fluid. Therefore, there is an effect that the flow rate of the fluid can be detected with high sensitivity as a change in the resistance value of the heating element.

Since the size of the sensor itself is very small, it has a very small heat capacity and thermal impedance, and as a result, it is possible to obtain a thermal time constant on the order of milliseconds.
In addition, since there is a gap surrounded by the first concave portion on the semiconductor substrate and the second concave portion of the upper structure, the heat generating element can have high thermal and physical insulating properties due to the air gap. . Further, since the heating element is protected by the substrate and the upper structure, there is an effect that it is possible to prevent the fluctuation of the sensor output characteristic due to the accumulation of dust and the damage due to the external disturbance.

According to the sixth aspect of the invention, the heat-sensitive element for detecting the temperature change caused by the flow of the fluid as the change of the resistance value is provided on both sides of the heat-generating element.
There is an effect that the flow rate of the fluid can be detected with high sensitivity. Further, there is an effect that the backflow can be detected by detecting the magnitude relation of the resistance values of the heat-sensitive elements formed on both sides of the heat-generating element in the vicinity thereof.

According to the invention of claim 7, the pressure difference due to the Karman vortex generated from the vortex generating portion provided in the flow path is
Since it is configured to be introduced into the pressure receiving portion via the pressure guiding tube, there is an effect that the flow rate of the fluid can be detected with high sensitivity.

In particular, when the protrusions are formed in the first and second recesses, respectively, the protrusions prevent the chip from bending in the thickness direction and stabilize the torsion about the beam portion of the pressure receiving portion. It has the effect of increasing the detection sensitivity. Furthermore, even if the flow may cause problems in the bearing strength of the pressure receiving part, without making any major changes to the manufacturing process,
The protrusion on the upper structure side and the pressure receiving portion can be integrated and reinforced, and the torsion of the pressure receiving portion around the beam portion can be made more stable.

According to the eighth aspect of the present invention, a plurality of projecting portions which are provided in parallel in the frame portion and at least one end portion of which is connected to the frame portion, and the temperature of the surrounding fluid which is formed on one of the projecting portions are controlled. Since it is configured to include a heat-sensitive element for detecting and a heat-generating element which is formed on the other protruding portion and generates heat so that the temperature is higher than the temperature of the fluid by a predetermined temperature, the thermal element between the heat-sensitive element and the heat-generating element is provided. Insulation can be achieved, and deterioration of detection accuracy due to heat conduction between these elements can be prevented. Therefore, there is an effect that the flow rate of the fluid can be detected with high sensitivity.

According to the invention of claim 9, a plurality of projecting portions provided in parallel in the frame portion and having at least one end connected to the frame portion, and the temperature of the surrounding fluid formed on one of the projecting portions are controlled. A first heat-sensitive element for detecting, a heat-generating element that is formed on the other protruding portion and generates heat so as to be higher than the temperature of the fluid by a predetermined temperature, and a second heat-sensitive element that detects the temperature of the heat-generating element. With this configuration, the flow rate of the fluid can be detected with high sensitivity by detecting the heating current flowing in the heating element.

According to the tenth aspect of the present invention, at least the mass portion, the support portion for supporting the mass portion, and the magnitude of the acceleration formed on the support portion and received by the mass portion are detected as a change in resistance value. Since it is configured to include one piezoresistor, the acceleration acting on the mass portion can be detected with high sensitivity. This semiconductor microsensor has a high degree of freedom in designing the size of the mass body and the supporting method, and has an effect that the range setting of the detected acceleration can be changed according to the application. Further, since the upper structure and the semiconductor substrate function as stoppers against an excessive amplitude of the mass part, it is effective in preventing damage.

According to the eleventh aspect of the present invention, the inter-layer structure is provided with a mass part formed in a part corresponding to the first recess, a first electrode formed in the mass part, and the mass part. A first electrode and a second electrode, wherein the first recess includes a second electrode and the second recess includes a third electrode, and a capacitance between the first electrode and the second electrode. Since the acceleration is detected by measuring the capacitance between the first electrode and the third electrode, the acceleration acting on the mass portion can be detected with high sensitivity by detecting the differential capacitance. There is an effect that can be detected.

According to the twelfth aspect of the present invention, since the supporting portion has a cantilever structure which is provided in the mass portion and is composed of one or more beam portions, the acceleration acting on the mass portion is highly sensitive. There is an effect that can be detected in.

According to the thirteenth aspect of the present invention, since the supporting portion is constituted by at least two beam portions provided at both ends of the mass portion, the acceleration acting on the mass portion can be accurately measured. There is an effect that it can be detected with high accuracy.

According to the fourteenth aspect of the present invention, the first sacrificial layer is provided at a predetermined position on the main surface having the <110> direction and the (100) plane of the semiconductor substrate, the central portion of the first sacrificial layer, and the first sacrificial layer. A first structure layer on the one main surface, a detection element at a predetermined position on the first structure layer, and a second structure layer on the first structure layer and the detection element.
And a second sacrificial layer including the first and second structural layers on the first sacrificial layer, the second sacrificial layer, and the second sacrificial layer. A third structure layer on the structure layer, an upper structure forming step of sequentially forming through holes at predetermined positions of the third structure layer, and a sacrifice layer removing step of removing the first and second sacrifice layers And a recess forming step of forming a first recess at a predetermined position of the semiconductor substrate by anisotropic etching, the semiconductor microsensor of this type having a three-dimensional structure,
There is an effect that it is possible to solve the complicated manufacturing process and the lack of strength, which have been conventionally brought about by bonding a plurality of members. Further, since it can be manufactured only by processing from the surface, it has good compatibility with a normal IC manufacturing process, high throughput, and low manufacturing cost. Further, since the sacrificial layer etching and the anisotropic etching are used together, the shape of the portion of the interlayer structure where the detection element is formed and protrudes into the gap and the upper structure and the semiconductor substrate are not limited to the crystal orientation. The effect is that the intervals can be designed arbitrarily.

According to the fifteenth aspect of the present invention, the step of forming the interlayer structure includes the step of forming a high-concentration impurity-added layer at a portion where a protrusion is to be formed on one main surface of the semiconductor substrate. Since the upper structure forming step includes the step of forming a groove in the portion of the second sacrificial layer where the protrusion is to be formed, the protrusion having the optimal shape is formed in each of the first and second recesses. There is an effect that can be formed.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a semiconductor microsensor according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a semiconductor microsensor according to an embodiment of the present invention.

FIG. 3 is a plan view showing an interlayer structure of a semiconductor microsensor according to an embodiment of the present invention.

FIG. 4 is a sectional view showing a Karman vortex flowmeter using a semiconductor microsensor according to an embodiment of the present invention.

5 is a cross-sectional view taken along the line BB of FIG.

6 is a process diagram showing a method of manufacturing a semiconductor microsensor according to another embodiment of the present invention, which is a cross-sectional view corresponding to the line AA in FIG. 1. FIG.

FIG. 7 is a process diagram showing a method of manufacturing a semiconductor microsensor according to another embodiment of the present invention, which is a cross-sectional view corresponding to the line C-C in FIG. 1.

8A and 8B are process diagrams showing a method of manufacturing a semiconductor microsensor according to a second embodiment of the present invention, which is a cross-sectional view corresponding to the line D-D in FIG. 1.

FIG. 9 is a sectional view showing a semiconductor microsensor of another embodiment of the present invention.

FIG. 10 is a sectional view showing a thermal type flow meter using a semiconductor microsensor according to another embodiment of the present invention.

FIG. 11 is a cross-sectional view showing a state in which a thermal type flow meter according to another embodiment of the present invention is installed in a flow path.

FIG. 12 is a plan view showing an interlayer structure of a sensor chip used in the thermal mass flow meter of another embodiment of the present invention.

FIG. 13 is a plan view showing an interlayer structure of a sensor chip used in a direct heating type mass flow meter of another embodiment of the present invention.

FIG. 14 is a cross-sectional view showing a state in which a direct heating type mass flow meter according to another embodiment of the present invention is installed in a flow path.

FIG. 15 is a plan view showing an interlayer structure of a sensor chip used in the indirectly heated mass flowmeter of another embodiment of the present invention.

FIG. 16 is a plan view showing an interlayer structure of a piezoresistive acceleration sensor according to another embodiment of the present invention.

FIG. 17 is a process drawing showing a method of manufacturing a semiconductor microsensor according to another embodiment of the present invention.

FIG. 18 is a sectional view showing a semiconductor microsensor according to another embodiment of the present invention.

FIG. 19 is a sectional view showing a capacitive acceleration sensor according to another embodiment of the present invention.

FIG. 20 is a plan view showing an interlayer structure of a capacitive acceleration sensor according to another embodiment of the present invention.

FIG. 21 is a sectional view showing a sensor chip used in a capacitive Karman vortex flowmeter according to another embodiment of the present invention.

22 is a plan view showing an interlayer structure of a sensor chip used in the capacitive Karman vortex flowmeter of FIG. 21. FIG.

FIG. 23 is a sectional view showing a flow velocity sensor as a conventional semiconductor microsensor.

FIG. 24 is a process diagram showing a method of manufacturing a conventional flow velocity sensor.

[Explanation of reference numerals] 7 heating element, 11 Si substrate (semiconductor substrate), 11a
Surface (one main surface), 13 pits (first recess), 1
4,34 Support shafts (projections) 21,91,101,1
11, 121, 141 interlayer structure, 22, 123 anchor part (frame part), 23 pressure receiving part, 24 piezoresistor,
25a, 25b Torsion bar (beam portion), 31 Upper structure, 32 Recessed portion (second recessed portion), 33a, 33b
Through hole, 51 flow path, 52 vortex generator (vortex generator), 5
3 pressure guiding tube, 54 sensor chip (semiconductor microsensor), 56 Karman vortex, 61 first sacrificial layer, 62
a, 62b First structure layer, 63 Second structure layer, 64
Second sacrificial layer, 65 third structural layer, 66 through hole,
92 bridge (projection part), 93 thermosensitive element, 122 mass body (mass part), 124 support beam (support part), 131
High concentration boron doped layer (high concentration impurity added layer), 132
groove.

Claims (15)

[Claims] 1. A semiconductor substrate in which a first recess is formed on one main surface having a <110> direction and a (100) plane, and a portion provided on the one main surface and corresponding to the first recess. 1
An interlayer structure on which one or more detection elements are formed; and a second concave portion that is provided on the interlayer structure and faces the interlayer structure and that faces the first concave portion. Two
A semiconductor microsensor, comprising: an upper structure having a plurality of through-holes communicating with the outside formed on the bottom surface of the concave portion. 2. The interlayer structure includes a frame portion provided around the first recess, and a pressure receiving portion provided in the frame portion and receiving a pressure introduced from the outside through the through hole. ,
2. The semiconductor microsensor according to claim 1, further comprising a plurality of beam portions which are provided between both ends of the pressure receiving portion and the frame portion and at least one of which has a piezoresistor. 3. The semiconductor micro according to claim 1, wherein each of the first recess and the second recess is provided with a protrusion that supports the pressure receiving portion within an elastic limit of the pressure receiving portion. Sensor. 4. The pressure receiving portion, which is formed in a portion corresponding to the first recess and receives the pressure introduced from the outside through the through hole, and the beam portion which supports the pressure receiving portion. And a first electrode formed in the pressure receiving portion, the semiconductor substrate includes a second electrode in the first recess, and the upper structure includes a third electrode in the second recess. The twisting of the beam portion is detected by measuring the capacitance between the first electrode and the second electrode and the capacitance between the first electrode and the third electrode. The semiconductor microsensor according to claim 1. 5. The interlayer structure includes a frame portion provided around the first recess, a protrusion provided in the frame portion, at least one end of which is connected to the frame portion, and the protrusion. The semiconductor microsensor according to claim 1, further comprising: a heating element that is formed in the portion and detects a flow rate from a change in resistance value due to a flow of surrounding fluid. 6. The semiconductor microsensor according to claim 5, wherein heat-sensitive elements for detecting a temperature change caused by a flow of fluid as a change in resistance value are provided on both sides of the heating element. 7. The pressure difference is provided by a vortex generator provided in the flow passage and a pressure guiding pipe provided near a downstream side of the vortex generator for guiding a pressure difference due to a Karman vortex generated from the vortex generator. The semiconductor microsensor according to any one of claims 2 to 5, wherein a flow rate of a fluid flowing through the flow path is measured by introducing a fluid into a pressure receiving portion. 8. The interlayer structure includes a frame portion provided around the first recess, and a plurality of protrusions provided in the frame portion in parallel and at least one end portion of which is connected to the frame portion. ,
A heat-sensitive element formed on one of the protrusions for detecting the temperature of the surrounding fluid, and a heat-generating element formed on the other protrusion to generate heat so as to be higher than the temperature of the fluid by a predetermined temperature. The semiconductor microsensor according to claim 1, which is characterized in that. 9. The interlayer structure includes a frame portion provided around the first recess, and a plurality of protrusions provided in the frame portion in parallel and at least one end portion of which is connected to the frame portion. ,
A first heat-sensitive element that is formed on one of the protrusions and detects the temperature of the surrounding fluid, a heat-generating element that is formed on the other of the protrusions and generates heat so as to be higher than the temperature of the fluid by a predetermined temperature, and the heat generation. The semiconductor microsensor according to claim 1, further comprising a second heat sensitive element that detects a temperature of the element. 10. The interlayer structure includes a mass portion formed in a portion corresponding to the first concave portion, a support portion supporting the mass portion, and an acceleration received by the mass portion formed in the support portion. 2. The semiconductor microsensor according to claim 1, further comprising: at least one piezoresistor that detects as a change in resistance value. 11. The interlayer structure includes a mass part formed in a part corresponding to the first recess, a first electrode formed in the mass part, and a support part supporting the mass part. The first recess includes a second electrode, and the second recess includes a third electrode, and the capacitance between the first electrode and the second electrode and the first electrode. The semiconductor microsensor according to claim 1, wherein the acceleration is detected by measuring the capacitance between the second electrode and the third electrode. 12. The semiconductor microsensor according to claim 10, wherein the supporting portion has a cantilever structure including one or more beam portions provided in the mass portion. . 13. The semiconductor microsensor according to claim 10, wherein the supporting portion is at least two beam portions provided at both ends of the mass portion. . 14. A semiconductor substrate in the <110> direction and (1
A first sacrificial layer at a predetermined position on one main surface having a (00) plane,
A first structural layer on the central portion of the first sacrificial layer and the one main surface; a detection element at a predetermined position on the first structural layer;
An inter-layer structure forming step of sequentially forming a second structure layer on the structure layer and the detection element, and the first sacrificial layer on the first sacrificial layer.
And a second sacrificial layer including the second structural layer, a third structural layer on the second sacrificial layer and the second structural layer, and a plurality of through holes at predetermined positions of the third structural layer. A step of sequentially forming an upper structure, a step of removing the first and second sacrificial layers, and a step of forming a first concave portion at a predetermined position of the semiconductor substrate by anisotropic etching. A method for manufacturing a semiconductor microsensor, comprising: 15. The interlayer structure forming step includes a step of forming a high-concentration impurity-added layer in a portion where a protrusion on the one main surface of the semiconductor substrate is to be formed, and the upper structure forming step includes 15. The method for manufacturing a semiconductor microsensor according to claim 14, further comprising the step of forming a groove in a portion of the sacrificial layer 2 where the protrusion is to be formed.