Sensor and electronic equipment
By shorting a doped substrate between the MEMS chip and the ASIC chip, noise is isolated and canceled, thus solving the problem of substrate noise affecting the performance of high-precision microsensors and improving the signal-to-noise ratio and the overall performance of the sensor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-04-10
AI Technical Summary
In high-precision microsensors, the impact of substrate noise on sensor performance is becoming increasingly prominent, leading to a decrease in signal-to-noise ratio and an increase in measurement error, which affects the applicability and reliability of the sensor in high-end applications.
By short-circuiting the first doped type substrate of the MEMS chip with the first doped region of the ASIC chip, power supply noise is isolated and the noise introduced by the bias circuit is mutually canceled between the MEMS and ASIC, thereby reducing the noise impact.
This improved the sensor's signal-to-noise ratio, enhanced its performance, and increased its applicability and reliability in high-end applications.
Smart Images
Figure CN121829609A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of microelectromechanical systems (MEMS) technology, and more specifically, to a sensor and electronic device. Background Technology
[0002] As core devices in the field of modern information sensing, microsensors have been widely used in many important fields such as consumer electronics, automotive electronics, industrial control, and medical health due to their advantages of miniaturization, low power consumption, and high integration. They have become a key foundation for realizing environmental sensing, condition monitoring, and data acquisition.
[0003] Currently, mainstream micro-sensor technology solutions typically consist of two parts: microelectromechanical systems (MEMS) and application-specific integrated circuits (ASICs). The two have a clear division of labor and work closely together to complete the conversion and processing of physical signals into usable signals.
[0004] In the fabrication of microsensors, due to the fundamental differences in functional requirements and performance indicators between MEMS and ASICs, they typically employ different manufacturing processes. Specifically, to achieve high-sensitivity sensing of specific physical signals, MEMS structures are often highly customized, requiring customized microfabrication processes to precisely realize their unique mechanical structures and electrical properties. ASICs, on the other hand, prioritize signal processing stability, reliability, and cost control, thus generally employing mature standard semiconductor processes for production. This ensures consistent product quality and leverages the economies of scale of standardized processes to reduce manufacturing costs. After the respective manufacturing processes of MEMS and ASICs are completed, the industry typically uses wire bonding and other wiring methods to electrically connect them, followed by packaging to form the final microsensor product.
[0005] Given the different manufacturing processes employed by MEMS and ASICs, during the operation of microsensors, to ensure that the MEMS receives the operating bias required to meet its performance specifications and to avoid bias instability caused by process differences, the substrate bias of the MEMS is typically provided separately. However, in practical applications, especially in the field of high-precision microsensors (such as high-precision pressure sensors and inertial sensors) where measurement accuracy is extremely high, the impact of substrate noise on sensor performance has become increasingly prominent and has become a key limiting factor. This substrate noise mainly originates from the noise inherent in the power supply providing the substrate bias for the MEMS, as well as noise generated during the operation of the ASIC's internal circuitry, which is coupled to the MEMS sensing structure through the substrate. Since the MEMS sensing structure is extremely sensitive to changes in electrical signals, substrate noise is directly superimposed on the original electrical signal after MEMS conversion, and then amplified after ASIC processing. This results in a decrease in the signal-to-noise ratio of the sensor output signal, an increase in measurement error, and seriously affects the applicability and reliability of high-precision microsensors in high-end applications. Summary of the Invention
[0006] One object of the present disclosure is to provide a new technical solution for a sensor capable of reducing substrate noise.
[0007] According to a first aspect of the present disclosure, a sensor is provided, including a MEMS chip and an ASIC chip; The MEMS chip includes a first substrate of a first doping type, a first input pin, and a first output pin, wherein the first input pin and the first output pin are both disposed on the first substrate. The ASIC chip includes a second substrate, a bias output pin, and a second input pin. The second substrate includes a first doped region of a first doping type, and the second input pin is disposed in the first doped region. The first input pin is connected to the bias output pin of the ASIC chip, and the first output pin is connected to the second input pin.
[0008] Optionally, the ASIC chip further includes a first power supply pin and a bias circuit, wherein the input terminal of the bias circuit is connected to the first power supply pin, and the output terminal of the bias circuit is connected to the bias output pin.
[0009] Optionally, the ASIC chip further includes a second power supply pin, the second substrate includes a second doped region of a second doping type, and the second power supply pin is disposed in the second doped region.
[0010] Optionally, the MEMS chip further includes a second output pin and an electromechanical module, wherein the output terminal of the electromechanical module is connected to the second output pin; The electromechanical module is used to convert the picked-up sensing information into detection signals.
[0011] Optionally, the ASIC chip further includes a third input pin, a third output pin, and a signal processing circuit. The third input pin is used to connect to the second output pin. The input terminal of the signal processing circuit is connected to the third input pin, and the output terminal of the signal processing circuit is connected to the third output pin. The signal processing circuit is used to perform signal processing on the detection signal.
[0012] Optionally, the ASIC chip is fabricated using CMOS technology.
[0013] Optionally, the MEMS chip and the ASIC chip are manufactured using different processes.
[0014] Optionally, the first doping type is N-doping, and the second doping type is P-doping.
[0015] Optionally, the sensor further includes a housing and a circuit board, the circuit board and the housing forming a chip accommodating space for placing the MEMS chip and the ASIC chip.
[0016] According to a second aspect of this disclosure, an electronic device is provided, including a sensor as described in the first aspect of this disclosure.
[0017] Through the embodiments of this disclosure, by short-circuiting the first substrate of the first doping type of the MEMS chip with the first doped region of the first doping type of the ASIC chip, the impact of noise on the sensor can be reduced, the signal-to-noise ratio of the sensor can be improved, and the performance of the sensor can be enhanced.
[0018] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description
[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.
[0020] Figure 1 A schematic diagram of a common sensor structure is shown; Figure 2 This is a block diagram of a sensor according to an embodiment of the present disclosure; Figure 3 This is a block diagram of a sensor according to another embodiment of the present disclosure. Detailed Implementation
[0021] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values of the components and steps set forth in these embodiments do not limit the scope of the invention.
[0022] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.
[0023] Techniques, methods, and apparatus known to those skilled in the art in the relevant field may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.
[0024] In all the examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.
[0025] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.
[0026] Figure 1 A schematic diagram of a common sensor structure is shown.
[0027] like Figure 1 As shown, the sensor 1000 includes a MEMS chip 1100 and an ASIC chip 1200. The substrate 1110 of the MEMS chip 1100 is an N-doped semiconductor substrate, and the ASIC chip 1200 is fabricated using CMOS technology. The ASIC chip 1200 also has an N-doped substrate 1210 and a P-doped substrate 1220.
[0028] Based on the bias requirements of the MEMS chip 1100, the substrate 1110 needs to be biased to a high potential to avoid leakage due to forward bias of the PN junction. Meanwhile, the P-doped substrate 1220 of the ASIC chip is typically grounded, and the N-doped substrate 1210 is directly connected to the power supply.
[0029] When considering the noise from the power supply, ground, and bias circuits, the contribution of these noises to the output can be derived. As shown in formula (1): Formula (1) Where α and β are the power supply noise gain and ground noise gain of ASIC chip 1200, respectively, and γ is the substrate bias noise gain of MEMS chip 1100. Indicates the noise of the power supply. Indicates ground noise, This indicates the noise of the bias circuit.
[0030] It can be seen that these irrelevant noises will increase the noise of the output signal, thereby reducing the signal-to-noise ratio of the sensor and ultimately leading to a decrease in the performance of the sensor.
[0031] This disclosure provides a sensor, such as Figure 2 As shown, the sensor 2000 may include a MEMS chip 2100 and an ASIC chip 2200.
[0032] MEMS chip 2100 includes a first substrate 2110 of a first doping type, a first input pin 2120, and a first output pin 2130, with the first input pin 2120 and the first output pin 2130 both disposed on the first substrate 2110.
[0033] The ASIC chip 2200 includes a second substrate 2210, a bias output pin 2220, and a second input pin 2230. The second substrate 2210 includes a first doped region 2211 of a first doping type, and the second input pin 2230 is disposed in the first doped region 2211.
[0034] The first input pin 2120 is connected to the bias output pin 2220 of the ASIC chip 2200, and the first output pin 2130 is connected to the second input pin 2230.
[0035] In this embodiment, the contribution of noise to the output As shown in formula (2): Formula (2) Where α and β are the power supply noise gain and ground noise gain of ASIC chip 1200, respectively, and γ is the substrate bias noise gain of MEMS chip 1100. Indicates ground noise, This indicates the noise of the bias circuit.
[0036] As can be seen, in this embodiment, by short-circuiting the first substrate 2110 of the first doping type of the MEMS chip 2100 with the first doped region 2211 of the first doping type of the ASIC chip 2200, and the first doped region 2211 of the first doping type is no longer directly connected to the power supply, power supply noise can be isolated.
[0037] Moreover, noise introduced by the bias circuit The noise can be canceled out between the MEMS chip 2100 and the ASIC chip 2200, and its noise gain coefficient is determined by... Reduce to .
[0038] Through the embodiments of this disclosure, by short-circuiting the first substrate of the first doping type of the MEMS chip with the first doped region of the first doping type of the ASIC chip, the impact of noise on the sensor can be reduced, the signal-to-noise ratio of the sensor can be improved, and the performance of the sensor can be enhanced.
[0039] In some embodiments, the MEMS chip 2100 and the ASIC chip 2200 are manufactured using different processes.
[0040] In this embodiment, the MEMS chip 2100 can be fabricated using a custom process.
[0041] In some embodiments, the ASIC chip 2200 is fabricated using CMOS technology.
[0042] In some embodiments, the first doping type is N-doping and the second doping type is P-doping.
[0043] In other embodiments, the first doping type is P-doping and the second doping type is N-doping.
[0044] In some embodiments, such as Figure 3 As shown, the ASIC chip 2200 also includes a first power supply pin 2240 and a bias circuit 2250. The input terminal of the bias circuit 2250 is connected to the first power supply pin 2240, and the output terminal of the bias circuit 2240 is connected to the bias output pin 2220.
[0045] In this embodiment, the bias circuit 2250 can output a DC bias voltage according to the level of the first power supply pin 2240, and output the DC bias voltage to the first substrate 2110 and the first doped region 2211 of the first doping type.
[0046] When the first doping type is N-doped and the second doping type is P-doped, the first power supply pin 2240 is used to input a high level.
[0047] When the first doping type is P-doped and the second doping type is N-doped, the first power supply pin 2240 is used to input a low level.
[0048] In some embodiments, such as Figure 3 As shown, the ASIC chip 2200 also includes a second power supply pin 2260, and the second substrate 2210 includes a second doped region 2212 of a second doping type. The second power supply pin 2260 is disposed in the second doped region 2212.
[0049] When the first doping type is N-doped and the second doping type is P-doped, the second power supply pin 2260 is used to input a low level.
[0050] When the first doping type is P-doped and the second doping type is N-doped, the second power supply pin 2260 is used to input a high level.
[0051] This embodiment allows for different voltage levels to be provided to the first doped region of the first doping type and the second doped region of the second doping type, ensuring the normal operation of the ASIC chip.
[0052] In some embodiments, such as Figure 3 As shown, the MEMS chip 2100 also includes a second output pin 2140 and an electromechanical module 2150. The output of the electromechanical module 2150 is connected to the second output pin 2140. The electromechanical module 2150 is used to convert the picked-up sensing information into a detection signal. The second output pin 2140 is used to connect to the ASIC chip 2200.
[0053] In this embodiment, the MEMS chip can convert the picked-up sensing information into a detection signal and transmit the detection signal to the ASIC chip.
[0054] In some embodiments, such as Figure 3 As shown, the ASIC chip 2200 also includes a third input pin 2270, a third output pin 2280, and a signal processing circuit 2290. The third input pin 2270 is used to connect to the second output pin 2140. The input terminal of the signal processing circuit 2290 is connected to the third input pin 2270, and the output terminal of the signal processing circuit 2290 is connected to the third output pin 2280. The signal processing circuit 2290 is used to perform signal processing on the detection signal.
[0055] In this embodiment, the signal processing circuit 2290 may process the detection signal in any one or more of the following ways: filtering, amplification, analog-to-digital conversion, table lookup, quadrature demodulation, fast Fourier transform, etc.
[0056] In this embodiment, the ASIC chip can perform signal processing on the detection signal output by the MEMS chip to obtain the sensing information picked up by the MEMS chip.
[0057] In some embodiments, the sensor further includes a housing and a circuit board, the circuit board and the housing together forming a chip accommodating space for placing MEMS chips and ASIC chips.
[0058] This embodiment also provides an electronic device, which may include the aforementioned sensor 1000.
[0059] This invention can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of the invention.
[0060] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.
[0061] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.
[0062] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages such as Smalltalk, C++, etc., and conventional procedural programming languages such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuits, such as programmable logic circuits, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), are personalized by utilizing state information from computer-readable program instructions. These electronic circuits can execute computer-readable program instructions to implement various aspects of the present invention.
[0063] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.
[0064] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.
[0065] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.
[0066] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions. It will be known to those skilled in the art that implementation in hardware, implementation in software, and implementation using a combination of software and hardware are equivalent.
[0067] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of the invention is defined by the appended claims.
Claims
1. A sensor, characterized in that, Including MEMS chips and ASIC chips; The MEMS chip includes a first substrate of a first doping type, a first input pin, and a first output pin, wherein the first input pin and the first output pin are both disposed on the first substrate. The ASIC chip includes a second substrate, a bias output pin, and a second input pin. The second substrate includes a first doped region of a first doping type, and the second input pin is disposed in the first doped region. The first input pin is connected to the bias output pin of the ASIC chip, and the first output pin is connected to the second input pin.
2. The sensor according to claim 1, characterized in that, The ASIC chip also includes a first power supply pin and a bias circuit. The input terminal of the bias circuit is connected to the first power supply pin, and the output terminal of the bias circuit is connected to the bias output pin.
3. The sensor according to claim 1, characterized in that, The ASIC chip further includes a second power supply pin, and the second substrate includes a second doped region of a second doping type, with the second power supply pin disposed in the second doped region.
4. The sensor according to claim 1, characterized in that, The MEMS chip also includes a second output pin and an electromechanical module, the output terminal of which is connected to the second output pin; The electromechanical module is used to convert the picked-up sensing information into detection signals.
5. The sensor according to claim 4, characterized in that, The ASIC chip further includes a third input pin, a third output pin, and a signal processing circuit. The third input pin is used to connect to the second output pin. The input terminal of the signal processing circuit is connected to the third input pin, and the output terminal of the signal processing circuit is connected to the third output pin. The signal processing circuit is used to process the detection signal.
6. The sensor according to claim 1, characterized in that, The ASIC chip is fabricated using CMOS technology.
7. The sensor according to claim 6, characterized in that, The MEMS chip and the ASIC chip are manufactured using different processes.
8. The sensor according to claim 3, characterized in that, The first doping type is N-doping, and the second doping type is P-doping.
9. The sensor according to claim 1, characterized in that, The sensor also includes a housing and a circuit board, the circuit board and the housing together forming a chip accommodating space for placing the MEMS chip and the ASIC chip.
10. An electronic device, characterized in that, Includes the sensor as described in any one of claims 1 to 9.