CN101005097A - Semiconductor piezoresistive sensor and method of operation thereof - Google Patents

Abstract

A semiconductor piezoresistive sensor is electrically connected with a circuit and comprises a semiconductor substrate, at least one piezoresistive element and a conductive material layer. The semiconductor substrate comprises a suspension film and a substrate, and the substrate is arranged adjacent to the periphery of the suspension film; the piezoresistive component is arranged in the suspension film and is electrically connected with the circuit; the conductive material layer is electrically connected with the suspension film.

Description

Semiconductor piezoresistive sensor and method of operation thereof

technical field

The invention relates to a semiconductor sensor, in particular to a semiconductor piezoresistive sensor and an operating method thereof.

Background technique

Pressure sensors are widely used in various fields, and the principle of pressure measurement includes piezoresistive type, piezoelectric type and capacitive type according to different application fields and requirements. Among them, the piezoresistive sensor has the advantages of high output voltage and high sensitivity, and uses the effect that the resistance value of the material changes with the stress as the measurement principle.

Please refer to FIG. 1, which is a schematic cross-sectional view of a conventional semiconductor piezoresistive sensor 1. The semiconductor piezoresistive sensor 1 includes a semiconductor substrate 10, a piezoresistive component 11 and a circuit 12, wherein the semiconductor substrate 10 (eg single crystal silicon substrate) includes a diaphragm 101 and a base 102 . The base material 102 is used to fix both ends of the suspension film 101 , and the piezoresistive element 11 is disposed in the suspension film 101 to serve as a sensing element of the semiconductor piezoresistive sensor 1 . The circuit 12 is electrically connected to the piezoresistive element 11, and the circuit 12 includes, for example, a complementary metal oxide semiconductor (MOS), a bridge circuit, an amplifier circuit or a logic circuit, etc., for receiving and processing the signal output by the piezoresistive element 11 .

The semiconductor substrate 10 can be an n-type semiconductor, and a p-type piezoresistive element 11 is formed by diffusion or ion implantation process, where the junction between the semiconductor substrate 10 and the piezoresistive element 11 forms a p-n junction (junction). As shown in FIG. 1, both ends of the piezoresistive element 11 can be electrically connected to a p+ type interconnect (interconnect) element 13 respectively, and the circuit 12 is opened by an insulating layer 14 covering the surface of the semiconductor substrate 10. An opening 141 is electrically connected to the p+-type internal connection element 13 .

As mentioned above, when a voltage V is applied to the semiconductor piezoresistive sensor 1, a negative space charge (negative space charge) is formed under the p-type piezoresistive element 11, and the negative space charge will drift with time, and The resistance value of the piezoresistive element 11 changes with time, and the output signal of the piezoresistive element 11 drifts with time. In addition, because the material of the insulating layer 14 covering the piezoresistive element 11 will bind some positive surface charges, since the positive surface charge will also drift with time, the phenomenon that the resistance value of the piezoresistive element 11 changes with time is more serious, thereby reducing the voltage. The accuracy of the output signal of the resistance component 11.

In order to solve the above-mentioned problems, as shown in Figure 2, the conventional technology forms an n+ type doped region 15 on the semiconductor substrate 10, and then applies an appropriate voltage to the n+ type doped region 15 to make the p-n junction form a reverse bias (reverse bias), thus limiting the current inside the piezoresistive component 11, thereby improving the phenomenon of reducing the measurement accuracy of the semiconductor piezoresistive sensor 1 due to leakage current. However, in the production process of the conventional p-type piezoresistive device 11, forming the n+-type doped region 15 on the n-type semiconductor substrate 10 requires additional process steps and costs such as photomask, doping and thermal diffusion. wait.

In view of this, how to provide a simple process that can effectively improve the phenomenon that the resistance value of the piezoresistive element changes with time is one of the important issues.

Contents of the invention

Therefore, in order to solve the above-mentioned problems, the present invention provides a semiconductor piezoresistive sensor and its operation method, which can reduce the manufacturing cost and effectively improve the measurement accuracy of the semiconductor piezoresistive sensor through simple process steps.

According to the object of the present invention, another semiconductor piezoresistive sensor is provided that is electrically connected to a circuit, which includes a semiconductor substrate, at least one piezoresistive element, and a conductive material layer. The semiconductor base material includes a suspension film and a base material. The base material is adjacent to the periphery of the suspension film; the piezoresistive component is arranged in the suspension film and electrically connected with the circuit; the conductive material layer is electrically connected with the suspension film.

According to another object of the present invention, a semiconductor piezoresistive sensor is provided that is electrically connected to a circuit, which includes a semiconductor substrate, at least one piezoresistive element, an insulating layer, and a shielding layer. The semiconductor substrate includes a suspension film and a base material. The base material is adjacent to the periphery of the suspension film; the piezoresistive component is arranged in the suspension film and electrically connected with the circuit; the insulating layer is arranged on the semiconductor substrate and covers the piezoresistor Component; the shielding layer is disposed on the insulating layer, covers at least part of the insulating layer, and is electrically connected to the suspension film.

In order to achieve the above object, a method of operating a semiconductor piezoresistive sensor according to the present invention includes the following steps: applying a first voltage to the circuit and applying a second voltage to the conductive material layer, wherein when the first voltage minus the second When the obtained value of the voltage is less than a conduction voltage between the piezoresistive component and the suspension film, a junction of the piezoresistive unit and the suspension film can form a reverse bias voltage or make the junction non-conductive.

To achieve the above object, another semiconductor piezoresistive sensor operating method according to the present invention includes the following steps: applying a first voltage to the circuit, applying a second voltage to the conductive material layer and applying a third voltage to the shielding layer , wherein when the value obtained by subtracting the second voltage from the first voltage is less than a conduction voltage between the piezoresistive component and the suspension film, a junction between the piezoresistive component and the suspension film can form a reverse bias or make the The interface is not conductive. In addition, the third voltage is used to stabilize a surface potential above the piezoresistive element

In order to achieve the above object, another semiconductor piezoresistive sensor operating method according to the present invention includes the following steps: applying a first voltage to the circuit and applying a second voltage to the shielding layer, wherein, when the first voltage minus the second voltage When the resulting value of the two voltages is less than a conduction voltage between the piezoresistive component and the suspension film, a junction between the piezoresistive component and the suspension film can form a reverse bias voltage or make the junction non-conductive.

Based on the above, a semiconductor piezoresistive sensor and its operating method according to the present invention utilize a conductive material layer or a shielding layer to electrically connect with the suspension film of the semiconductor substrate, wherein the conductive material layer and the shielding layer are It is composed of conductive material and non-insulating material respectively. The semiconductor piezoresistive sensor is constructed in a circuit. By applying an appropriate voltage to the conductive material layer or the shielding layer, the junction of the piezoresistive component and the suspension film forms a reverse direction. The bias voltage may make the junction non-conductive, so the current is limited in the piezoresistive device, thereby improving the phenomenon that the output signal of the piezoresistive device drifts with time. Compared with the conventional technology, the present invention does not need to form a semiconductor doped region different from the piezoresistive element on the semiconductor substrate, so the process steps are effectively simplified, the manufacturing cost is reduced, and the measurement accuracy of the semiconductor piezoresistive sensor is improved. Spend.

In order to make the above-mentioned and other purposes, features, and advantages of the present invention more clearly understood, a preferred embodiment is specifically cited below, together with the accompanying drawings, and is described in detail as follows:

Description of drawings

1 and 2 are schematic cross-sectional views of a conventional semiconductor piezoresistive sensor.

3A and 3B are schematic cross-sectional views of a semiconductor piezoresistive sensor according to the first embodiment of the present invention.

4A and 4B are schematic cross-sectional views of a semiconductor piezoresistive sensor according to a second embodiment of the present invention.

5A and 5B are schematic cross-sectional views of a semiconductor piezoresistive sensor according to a third embodiment of the present invention.

Detailed ways

The semiconductor piezoresistive sensor and its operating method according to preferred embodiments of the present invention will be described below with reference to related drawings, wherein the same components will be described with the same reference symbols.

first embodiment

Please refer to FIG. 3A and FIG. 3B at the same time, according to a semiconductor piezoresistive sensor 2 according to the first embodiment of the present invention, it includes a semiconductor substrate 20, an insulating layer 23, at least one piezoresistive component 21, and at least one internal connection Component 24 and a conductive material layer 22 . The semiconductor piezoresistive sensor 2 is electrically connected to a circuit 3, such as a bridge circuit or a temperature compensation circuit.

The semiconductor substrate 20 includes a suspension film 201 and a substrate 202 . The substrate 202 is adjacent to the periphery of the suspension film 201. In this embodiment, the suspension film 201 is an n-type doped region, and the piezoresistive component 21 is a p-type doped region. In detail, the structure of the semiconductor substrate 20 can be composed of n- The epitaxial layer is formed on a p-type wafer. The n-type dopant is phosphorous, arsenic, etc., and the p-type dopant is boron, gallium, boron difluoride (BF2), etc., for example.

The piezoresistive component 21 is arranged in the suspension film 201 and is electrically connected with the circuit 3. In this embodiment, the piezoresistive component 21 is a p-type piezoresistive component 21, and the p-type piezoresistive component 21 is formed by diffusion or ion implantation. Dopants are injected into the suspension film 201 . A P-N junction is formed between the formed p-type piezoresistive component 21 and the n-type doped region of the suspension film 201, so when a pressure to be measured is applied to the suspension film 201, the suspension film 201 deforms to make the piezoresistive The resistance value of the component 21 changes accordingly. Then, use the circuit 3 electrically connected to the piezoresistive element 21 to perform signal processing on the change of the resistance value, such as signal amplification and temperature compensation, or further convert the received resistance value change into The corresponding pressure to be measured is displayed on an external screen.

The insulating layer 23 is disposed on the semiconductor substrate 20 and covers the piezoresistive element 21 . The material of the insulating layer 23 is, for example, silicon oxide, silicon nitride, silicon oxynitride, etc. or a combination thereof.

The semiconductor piezoresistive sensor 2 of this embodiment further includes at least one interconnection component 24, as shown in Figure 3A and Figure 3B, the at least one interconnection component 24 that the semiconductor piezoresistive sensor 2 includes is, for example, a first interconnection Component 241 and a second internal connection component 242, which are electrically connected to both ends of the piezoresistive component 21, wherein the piezoresistive component 21 is electrically connected to the circuit 3 through the first internal connection component 241, for example, the first internal connection The component 241 can be used to connect with other components in the bridge circuit (not shown). The insulating layer 23 electrically connects the circuit 3 with the first internal connection component 241 by opening an opening 231 . In this embodiment, the interconnection component 24 is, for example, a p+ type semiconductor layer.

As shown in FIG. 3A, the conductive material layer 22 is disposed on the insulating layer 23, and the conductive material layer 22 is directly contacted with the suspension film 201 to be electrically connected through another opening 232 of the insulation layer 23, and the suspension film 201 is The original substrate dopant concentration (N-). The contact method between the conductive material layer 22 and the suspension film 201 can be ohmic contact or Schottky contact.

Alternatively, as shown in FIG. 3B , the region in contact with the conductive material layer 22 is a high dopant concentration region (p+) 25 . The p-type doped region 25 between the conductive material layer 22 and the suspension film 201 is arranged in the suspension film 201 relative to the conductive material layer 22, and forms an ohmic contact or Xiao Teki contacts. The p-type dopant used in the p-type doped region 25 is a high doping concentration, so it is a p+-type doped region. It should be particularly noted here that the p+-type doped region 25 does not require additional steps to be achieved, and can be performed simultaneously in the process of forming the interconnection element 24 .

Whether it is the semiconductor piezoresistive sensor 2 shown in FIG. 3A or FIG. 3B, the potential of the suspension film (N-) 201 can be controlled by applying a voltage V1+ appropriately, so that the potential of the suspension film (N-) 201 will not follow the Time drift, wherein the voltage V1+ can be the bridge circuit voltage (ex. VB+) of the piezoresistive component 21 or other voltages (ex. Vs+ from the temperature compensation circuit) higher than the bridge circuit voltage of the sensor, so that the piezoresistive component 21 and The junction of the suspension film 201 forms a reverse bias (reverse bias) or makes the P-N junction non-conductive (the voltage across the PN junction is less than the conduction voltage), which can limit the current inside the resistance component and control the suspension film 201 Potential, further, through such a structural layout design and arrangement, the purpose of improving the time drift of the output signal of the piezoresistive sensor 2 can be achieved.

second embodiment

Please refer to FIG. 4A and FIG. 4B at the same time. According to the second embodiment of the present invention, a semiconductor piezoresistive sensor 4 includes a semiconductor substrate 20, an insulating layer 23, at least one piezoresistive component 21, and at least one internal connection. Component 24 and a shield layer (Shield layer) 26. The semiconductor piezoresistive sensor 4 is electrically connected to a circuit 3, such as a bridge circuit or a temperature compensation circuit. In this embodiment, the structural features, materials, arrangement, connection relationship and functions of the semiconductor substrate 20, the piezoresistive component 21, the interconnection component 24, the insulating layer 23 and the circuit 3 are all as described in the first embodiment, so No longer.

The difference between this embodiment and the first embodiment is that the shielding layer 26 is arranged on the insulating layer 23, and covers at least part of the semiconductor piezoresistive sensor 4 of this embodiment does not have a conductive material layer 22, but compared with the first In this embodiment, a shielding layer 26 is added. The shielding layer 26 is disposed on the insulating layer 23, and covers at least part of the insulating layer 23 and is electrically connected to the suspension film 201. In more detail, the insulating layer 23 opens an opening 232, and the shielding layer 26 is connected to the suspension film through the opening 232. The film 201 is in direct contact for electrical connection, and the suspension film 201 is at the original substrate dopant concentration (N-), as shown in FIG. 4A . The contact mode of the shielding layer 26 and the suspension film 201 can be an ohmic contact or a Schottky contact. The shielding layer 26 is made of non-insulating material, and its thermal coefficient of expansion (TCE) is preferably between -15ppm/°C to +15ppm/°C.

Alternatively, as shown in FIG. 4B , the area in contact with the shielding layer 26 is a high dopant concentration area (p+) 25 . The p-type doped region 25 located between the shielding layer 26 and the suspension film 201 is arranged in the suspension film 201 relative to the shielding layer 26, and forms an ohmic contact or a Schottky contact with the shielding layer 26 through the opening 232 of the insulating layer 23 . The p-type dopant used in the p-type doped region 25 is a high doping concentration, so it is a p+-type doped region. It should be particularly noted here that the p+-type doped region 25 does not require additional steps to be achieved, and can be performed simultaneously in the process of forming the interconnection element 24 .

Whether it is the semiconductor piezoresistive sensor 4 shown in FIG. 4A or FIG. 4B, the potential of the suspension film (N-) 201 can be controlled by applying a voltage V2+ appropriately, so that the potential of the suspension film (N-) 201 will not drift . In addition, the piezoresistive element 21 under the insulating layer 23 is properly shielded through the shielding layer 26 , and the voltage V2+ is applied to stabilize the surface potential above the piezoresistive element 21 so that the surface potential will not drift with time. The voltage V2+ can be the bridge circuit voltage of the piezoresistive component 21 (such as VB+) or other voltages higher than the sensor bridge circuit voltage (such as Vs+ from the temperature compensation circuit), so that the connection between the piezoresistive component 21 and the suspension film 201 Form a reverse bias (reverse bias) or make the P-N junction non-conductive (the voltage across the PN junction is less than the conduction voltage), the current can be limited inside the resistance component and the potential of the suspension film 201 can be controlled. Further, Through such structural layout design and arrangement, the purpose of improving the time drift of the output signal of the piezoresistive sensor 4 can be achieved.

third embodiment

Please refer to FIG. 5A and FIG. 5B at the same time, according to a semiconductor piezoresistive sensor 5 according to the third embodiment of the present invention, it includes a semiconductor substrate 20, an insulating layer 23, at least one piezoresistive component 21, and at least one internal connection Component 24, a conductive material layer 22 and a shield layer (Shield layer) 26. The semiconductor piezoresistive sensor 5 is electrically connected to a circuit 3, such as a bridge circuit or a temperature compensation circuit. As shown in FIG. 5B, the semiconductor piezoresistive sensor 2 further includes a p-type doped region 25 disposed between 22 and the suspension film 201. In this embodiment, the p-type doped region 25 is disposed on the suspension film 201 relative to 22. ohmic contact or Schottky contact is formed through the opening 232 and 22 of the insulating layer 23, wherein the p-type doped region 25 is a high doping concentration, that is, the p+-type doped region. In this embodiment, the structural features, materials, arrangement, connection relationship and functions of the semiconductor substrate 20, the piezoresistive component 21, the interconnection component 24, the insulating layer 23 and the circuit 3 are all as described in the first embodiment, so No longer.

The difference between this embodiment and the first and second embodiments is that the semiconductor piezoresistive sensor 5 of this embodiment has both a conductive material layer 22 and a shielding layer 26 . The conductive material layer 22 is disposed on the insulating layer 23, and through another opening 232 of the insulating layer 23, the conductive material layer 22 is in direct contact with the suspension film 201 for electrical connection, and the suspension film 201 is the original substrate doped mass concentration (N-). The contact mode between the conductive material layer 22 and the suspension film 201 can be ohmic contact or Schottky contact, as shown in FIG. 5A . In addition, the semiconductor piezoresistive sensor 5 of this embodiment further includes a shielding layer 26 disposed on the insulating layer 23 and covering at least part of the insulating layer 23, wherein the shielding layer 26 is made of a non-insulating material, and its thermal expansion The thermal coefficient of expansion (TCE) is preferably between -15ppm/°C to +15ppm/°C, so as to prevent the semiconductor piezoresistive sensor 5 from having a large thermal expansion coefficient difference between the shielding layer 26 and the semiconductor substrate 20. Zero output (offset) and thermal specifications (such as TCO) can also avoid the occurrence of mechanical hysteresis. Here, as shown in FIG. 5 , the shielding layer 26 is not connected to the conductive material layer 22 , but according to the circuit design, the shielding layer 26 and the conductive material layer 22 can also be electrically connected to each other.

Alternatively, as shown in FIG. 5B , the region in contact with the conductive material layer 22 is a high dopant concentration region (p+) 25 . The p-type doped region 25 between the conductive material layer 22 and the suspension film 201 is arranged in the suspension film 201 relative to the conductive material layer 22, and forms an ohmic contact or Xiao Teki contacts. The p-type dopant used in the p-type doped region 25 is a high doping concentration, so it is a p+-type doped region. It should be particularly noted here that the p+-type doped region 25 does not require additional steps to be achieved, and can be performed simultaneously in the process of forming the interconnection element 24 .

Regardless of the semiconductor piezoresistive sensor 5 shown in Figure 5A or Figure 5B, the potential of the suspension film (N-) 201 can be controlled by applying a voltage V4+ appropriately, so that the potential of the suspension film (N-) 201 will not drift . In addition, the piezoresistive element 21 under the insulating layer 23 is properly shielded through the shielding layer 26, and the voltage V3+ is applied to stabilize the surface potential above the piezoresistive element 21 so that the surface potential will not drift with time. The voltages V3+ and V4+ can be the bridge circuit voltage (ex. VB+) of the piezoresistive component 21 or other voltages higher than the sensor bridge circuit voltage (ex. Vs+ from the temperature compensation circuit), so that the piezoresistive component 21 and the suspension The junction of the film 201 forms a reverse bias (reverse bias) or makes the P-N junction non-conductive (the voltage across the PN junction is less than the conduction voltage), which can limit the current inside the resistance component and control the suspension film 201 Potential, further, through such a structural layout design and arrangement, the purpose of improving the time drift of the output signal of the piezoresistive sensor 5 can be achieved.

An operating method of a semiconductor piezoresistive sensor according to a preferred embodiment of the present invention is applied to the semiconductor piezoresistive sensor 2 shown in Figure 3A and Figure 3B, the operating method includes the following steps: applying a voltage V1 to the conductive Material layer 22 and a voltage V0 is applied to the circuit 3. When the value obtained by subtracting the voltage V1 from the voltage V0 is less than the conduction voltage between the piezoresistive component 21 and the suspension film 201, the junction between the piezoresistive component 21 and the suspension film 201 It can form a reverse bias or make the P-N junction non-conductive, thereby limiting the current inside the piezoresistive component 21 and improving the time drift of the output signal of the piezoresistive sensor 2 . Wherein, the voltage V0 or the voltage V1 may be a voltage of a bridge circuit or a temperature compensation circuit connected to the semiconductor piezoresistive sensor 2 , or a voltage higher than that of the bridge circuit or the temperature compensation circuit.

Another method of operating a semiconductor piezoresistive sensor according to a preferred embodiment of the present invention is applied to the semiconductor piezoresistive sensor 4 shown in FIG. 4A and FIG. 4B. The operating method includes the following steps: applying a voltage V2 to The shielding layer 26 and applying a voltage V0 to the circuit 3, when the value obtained by subtracting the voltage V1 from the voltage V0 is less than the conduction voltage between the piezoresistive component 21 and the suspension film 201, the junction between the piezoresistive component 21 and the suspension film 201 It can form a reverse bias or make the P-N junction non-conductive. At the same time, the voltage V2 applied to the shielding layer 26 can be used to stabilize the surface potential above the piezoresistive element 21, thereby limiting the current inside the piezoresistive element 21 and improving the voltage. The purpose of drifting when the resistive sensor 4 outputs the signal. The voltage V0 or the voltage V2 is, for example, the voltage of the bridge circuit or the temperature compensation circuit, or is higher than the voltage of the bridge circuit or the temperature compensation circuit.

Another method of operating a semiconductor piezoresistive sensor according to a preferred embodiment of the present invention is applied to the semiconductor piezoresistive sensor 5 shown in FIG. 5A and FIG. 5B. The operating method includes the following steps: applying a voltage V4 to Conductive material layer 22, apply a voltage V0 to the circuit 3 and apply a voltage V3 to the shielding layer 26, when the value obtained by subtracting the voltage V4 from the voltage V0 is less than the conduction voltage between the piezoresistive component 21 and the suspension film 201, the voltage The junction between the resistance component 21 and the suspension film 201 can form a reverse bias or make the P-N junction non-conductive, thereby limiting the current inside the piezoresistive component 21 and improving the time drift of the output signal of the piezoresistive sensor 5. . The voltage V0, the voltage V3 or the voltage V4 is, for example, the voltage of the bridge circuit or the temperature compensation circuit, or is higher than the voltage of the bridge circuit or the temperature compensation circuit.

In summary, according to the semiconductor piezoresistive sensor and its operating method of the present invention, it utilizes a conductive material layer or a shielding layer to be electrically connected to the suspension film of the semiconductor substrate, wherein the conductive material layer and the shielding layer are composed of Composed of conductive materials and non-insulating materials, the semiconductor piezoresistive sensor is constructed in a circuit, and by applying an appropriate voltage to the conductive material layer or shielding layer, the voltage difference between it and the circuit is lower than that of the piezoresistive component The conduction voltage with the suspension film, so the junction between the piezoresistive component and the suspension film is not conductive to limit the current in the piezoresistive component, thereby improving the phenomenon that the output signal of the piezoresistive component drifts with time. Compared with the conventional technology, the present invention does not need to form a semiconductor doped region different from the piezoresistive element on the semiconductor substrate, so the process steps are effectively simplified, the manufacturing cost is reduced, and the measurement accuracy of the semiconductor piezoresistive sensor is improved. Spend.

The above descriptions are illustrative only, not restrictive. Any equivalent modifications or changes made without departing from the spirit and scope of the present invention shall be included in the appended claims.

Claims (20)

1. A semiconductor piezoresistive sensor electrically connected to a circuit, the semiconductor piezoresistive sensor comprising: A semiconductor substrate, including a suspension film and a base material, the base material is adjacent to the periphery of the suspension film; At least one piezoresistive element is disposed in the suspension film and electrically connected with the circuit; and A conductive material layer is electrically connected with the suspension film. 2. The semiconductor piezoresistive sensor according to claim 1, further comprising a p-type doped region disposed in the suspension film and in contact with the conductive material layer. 3. The semiconductor piezoresistive sensor according to claim 2, wherein the conductive material layer forms an ohmic contact or a Schottky contact with the p-type doped region. 4. The semiconductor piezoresistive sensor as claimed in claim 1, wherein the conductive material layer forms an ohmic contact or a Schottky contact with the suspension film. 5. The semiconductor piezoresistive sensor according to claim 1, further comprising an insulating layer disposed on the semiconductor substrate and covering the piezoresistive element. 6. The semiconductor piezoresistive sensor as claimed in claim 5, wherein the insulating layer comprises silicon oxide, silicon nitride, silicon oxynitride, etc. or a combination thereof. 7. The semiconductor piezoresistive sensor according to claim 5, further comprising a shielding layer disposed on the insulating layer and covering at least part of the insulating layer, and the shielding layer is electrically connected to the conductive material layer . 8. A semiconductor piezoresistive sensor electrically connected to a circuit, the semiconductor piezoresistive sensor comprising: A semiconductor substrate, including a suspension film and a base material, the base material is adjacent to the periphery of the suspension film; At least one piezoresistive element is arranged in the suspension film and electrically connected with the circuit; an insulating layer disposed on the semiconductor substrate and covering the piezoresistive element; and A shielding layer is arranged on the insulating layer, covers at least part of the insulating layer, and is electrically connected with the suspension film. 9. The semiconductor piezoresistive sensor according to claim 8, further comprising a p-type doped region disposed in the suspension film and in contact with the shielding layer. 10. The semiconductor piezoresistive sensor according to claim 9, wherein the shielding layer forms an ohmic contact or a Schottky contact with the p-type doped region. 11. The semiconductor piezoresistive sensor as claimed in claim 8, wherein the shielding layer forms an ohmic contact or a Schottky contact with the suspension film. 12. The semiconductor piezoresistive sensor as claimed in claim 8, wherein the shielding layer is made of non-insulating material. 13. The semiconductor piezoresistive sensor according to claim 7 or 8, wherein the shielding layer has a thermal expansion coefficient ranging from -15 ppm/°C to +15 ppm/°C. 14. The semiconductor piezoresistive sensor according to claim 1 or 8, further comprising at least one interconnection element electrically connected to the circuit and the piezoresistive element. 15. The semiconductor piezoresistive sensor according to claim 1 or 8, wherein the suspension film is an n-type doped region, and the piezoresistive element is a p-type doped region. 16. The semiconductor piezoresistive sensor according to claim 1 or 8, wherein the piezoresistive element is electrically connected to the circuit, and the circuit is a bridge circuit or a temperature compensation circuit. 17. The semiconductor piezoresistive sensor according to claim 1 or 8, wherein the insulating layer comprises silicon oxide, silicon nitride, silicon oxynitride, etc. or a combination thereof. 18. A method for operating a semiconductor piezoresistive sensor, applied to the semiconductor piezoresistive sensor as claimed in claim 1 or 7, comprising the following steps: applying a first voltage to the circuit; and applying a second voltage to the conductive material layer; Wherein when the value obtained by subtracting the second voltage from the first voltage is less than a conduction voltage between the piezoresistive component and the suspension film, a junction between the piezoresistive component and the suspension film can form a reverse bias or make the junction non-conductive. 19. The operating method as claimed in claim 18, further comprising: applying a third voltage to the shielding layer, the third voltage is used to stabilize a surface potential above the piezoresistive element. 20. A method for operating a semiconductor piezoresistive sensor, applied to the semiconductor piezoresistive sensor as claimed in claim 8, comprising the following steps: applying a first voltage to the circuit; and applying a second voltage to the shielding layer; Wherein when the value obtained by subtracting the second voltage from the first voltage is less than a conduction voltage between the piezoresistive component and the suspension film, a junction between the piezoresistive component and the suspension film can form a reverse bias or make the junction non-conductive.

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