Preparation method and device of sound-sensitive chip and electronic equipment

Abstract

The invention discloses a preparation method and device of a sound-sensitive chip and electronic equipment. Relates to the field of semiconductor device manufacturing, and the method comprises the following steps: implanting oxygen ions into a silicon wafer to obtain silicon-on-insulator consisting of top silicon, a buried oxygen layer and substrate silicon; determining a preset resistance value of a sound-sensitive resistor in the sound-sensitive chip according to the use requirement of the sound-sensitive chip; the size parameters of the acoustic resistors are calculated according to the preset resistance value, a plurality of acoustic resistors are manufactured on the top layer silicon according to the size parameters, and the plurality of acoustic resistors form a Wheatstone measuring bridge; and constructing the top layer silicon into a beam film structure to obtain the sound-sensitive chip. According to the invention, the problems of low sensitivity and poor stability of a traditional sound-sensitive chip in the prior art are solved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor device manufacturing, and more specifically, to a method and device for preparing an acoustic sensor chip, and an electronic device. Background Art

[0002] With the rapid development of microelectronics and micromachining technologies, MEMS (Micro-Electro-Mechanical Systems) sensors have been widely used in consumer electronics, automotive electronics, industrial control and other fields due to their small size, light weight, low power consumption and superior performance.

[0003] As a key component in MEMS sensors, the performance of acoustic chips directly affects the overall performance of the sensor. The structural design of traditional acoustic chips is relatively simple, using a simple flat plate structure as the sensitive unit, but the sensitive unit of the flat plate structure is not sensitive enough to the sound wave signal because its surface area is limited and it cannot effectively capture the sound wave signal.

[0004] Traditional acoustic sensor chips use more common piezoelectric materials such as quartz crystals or piezoelectric ceramics as sensitive units. However, quartz crystals are more expensive and their performance may change when affected by environmental factors such as temperature. Piezoelectric ceramics may have problems such as aging and fatigue, affecting their stability and reliability in long-term use.

[0005] Currently, no effective solution has been proposed to address the problems of low sensitivity and poor stability of traditional acoustic sensing chips in related technologies. Summary of the invention

[0006] The present application provides a method, device and electronic device for preparing an acoustic sensor chip to solve the problem of low sensitivity and poor stability of traditional acoustic sensor chips in the related art.

[0007] According to one aspect of the present application, a method for preparing an acoustic sensor chip is provided. The method includes: implanting oxygen ions into a silicon wafer to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, a buried oxide layer and substrate silicon; determining the preset resistance value of the acoustic resistor in the acoustic sensor chip according to the use requirements of the acoustic sensor chip; calculating the size parameters of the acoustic resistor according to the preset resistance value, and making multiple acoustic resistors on the top silicon according to the size parameters, wherein the multiple acoustic resistors constitute a Wheatstone measurement bridge; constructing the top silicon into a beam membrane structure to obtain the acoustic sensor chip.

[0008] Optionally, implanting oxygen ions into a silicon wafer to obtain silicon-on-insulator includes: obtaining a single crystal silicon wafer, and implanting oxygen ions with a dose greater than a preset value below the surface of the silicon wafer; placing the silicon wafer after oxygen ion implantation in a high temperature environment for annealing until a silicon dioxide insulating layer of uniform thickness is formed below the surface of the single crystal silicon wafer, thereby obtaining silicon-on-insulator.

[0009] Optionally, calculating the size parameters of the acoustic resistor according to the preset resistance value includes: determining the resistance value of the resistor block per unit area, and calculating the current upper limit value according to the resistance value and the resistance power upper limit value; determining the width value of the acoustic resistor according to the current upper limit value and the preset current value; determining the length value of the acoustic resistor according to the preset resistance value, the resistance value of the resistor block and the width value; and determining the length value and the width value as the size parameters of the acoustic resistor.

[0010] Optionally, manufacturing multiple acoustic resistors on the top silicon according to size parameters includes: determining the arrangement position of each acoustic resistor according to the style of the Wheatstone measurement bridge; and implanting ions into the top silicon according to the size parameters through an ion implantation process at each arrangement position to obtain the acoustic resistors.

[0011] Optionally, the method further includes: changing the conductivity type of the top silicon to P type and changing the conductivity type of the substrate silicon to N type through a doping process.

[0012] Optionally, constructing the top silicon into a beam membrane structure includes: using ICP etching technology to make the top silicon into a beam membrane structure, wherein the acoustic resistor is integrated on the beam membrane structure so that the resistance of the acoustic resistor changes with the vibration of the beam membrane structure.

[0013] Optionally, determining the preset resistance value of the acoustic resistor in the acoustic chip according to the use requirements of the acoustic chip includes: determining the application scenario of the acoustic chip, and determining the preset resistance value of each acoustic resistor of the Wheatstone measurement bridge in the acoustic chip according to the application scenario, wherein the preset resistance value of each acoustic resistor of the Wheatstone measurement bridge is the same.

[0014] According to another aspect of the present application, a device for preparing an acoustic sensor chip is provided. The device includes: an injection unit, which is used to inject oxygen ions into a silicon wafer to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, a buried oxide layer and substrate silicon; a determination unit, which is used to determine the preset resistance value of the acoustic resistor in the acoustic sensor chip according to the use requirements of the acoustic sensor chip; a calculation unit, which is used to calculate the size parameters of the acoustic resistor according to the preset resistance value, and to make multiple acoustic resistors on the top silicon according to the size parameters, wherein the multiple acoustic resistors constitute a Wheatstone measurement bridge; a construction unit, which is used to construct the top silicon into a beam membrane structure to obtain the acoustic sensor chip.

[0015] According to another aspect of the present invention, a computer program product is also provided, including a computer program, which, when executed by a processor, implements a method for preparing a sound-sensitive chip provided in the aforementioned embodiment of the present application.

[0016] According to another aspect of the present invention, there is also provided an electronic device comprising one or more processors and a memory; the memory stores computer-readable instructions, and the processor is used to execute the computer-readable instructions, wherein when the computer-readable instructions are executed, a method for preparing a sound-sensitive chip provided in the aforementioned embodiment is executed.

[0017] Through the present application, the following steps are adopted: oxygen ions are implanted into a silicon wafer to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, buried oxide layer and substrate silicon; the preset resistance value of the acoustic resistor in the acoustic chip is determined according to the use requirements of the acoustic chip; the size parameters of the acoustic resistor are calculated according to the preset resistance value, and multiple acoustic resistors are made on the top silicon according to the size parameters, wherein the multiple acoustic resistors constitute a Wheatstone measurement bridge; the top silicon is constructed into a beam-membrane structure to obtain the acoustic chip. By using silicon on insulator to make acoustic resistors, construct a Wheatstone measurement bridge and a beam-membrane structure, the conversion and amplification of the acoustic wave signal are realized, and the problem of low sensitivity and poor stability of the traditional acoustic chip in the related art is solved, thereby achieving the effect of improving the sensitivity and accuracy of the acoustic chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 is a flow chart of a method for preparing an acoustic sensor chip according to an embodiment of the present application;

[0020] Figure 2 This is a structural diagram of materials for making an acoustic sensor chip according to an embodiment of the present application;

[0021] Figure 3 is a schematic diagram of a device for preparing an acoustic sensitive chip according to an embodiment of the present application;

[0022] Figure 4 It is a schematic diagram of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0026] It should be noted that the preparation method, device and electronic device of the acoustic sensor chip determined in the present disclosure can be used in the field of semiconductor device manufacturing, and can also be used in any field except the field of semiconductor device manufacturing. The application field of the preparation method, device and electronic device of the acoustic sensor chip determined in the present disclosure is not limited.

[0027] It should be noted that the collected information, user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) used in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of relevant data are in compliance with the relevant laws, regulations and standards of the relevant regions, necessary confidentiality measures are taken, and public order and good customs are not violated. Corresponding operation entrances are provided for users to choose to authorize use or refuse use. If the user chooses to refuse, the expert decision-making process is entered. For example, an interface is set between this system and relevant users or institutions. Before obtaining relevant information, it is necessary to send an acquisition request to the aforementioned user or institution through the interface, and obtain relevant information after receiving the consent information fed back by the aforementioned user or institution.

[0028] The embodiments or examples of the present disclosure are not exhaustive, but are only illustrative of some embodiments or examples, and are not intended to be specific limitations on the scope of protection of the present disclosure. In the absence of contradiction, each step in a certain embodiment or example can be implemented as an independent example, and the steps can be combined arbitrarily. For example, the scheme after removing some steps in a certain embodiment or example can also be implemented as an independent example, and the order of the steps in a certain embodiment or example can be arbitrarily exchanged. In addition, the optional methods or optional examples in a certain embodiment or example can be combined arbitrarily; in addition, the various embodiments or examples can be combined arbitrarily, for example, some or all steps of different embodiments or examples can be combined arbitrarily, and a certain embodiment or example can be combined arbitrarily with the optional methods or optional examples of other embodiments or examples.

[0029] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0030] SOI silicon wafer: SOI (Silicon on Insulator) is a semiconductor technology that uses an insulating layer to isolate the silicon chip from the substrate to reduce electron diffraction and cross-coupling effects. SOI technology can improve transistor performance, reduce power consumption, and increase the speed and reliability of integrated circuits.

[0031] SIMOX technology: SIMOX (Separation by IMplanted Oxygen, molecular beam silicon oxide) technology is a semiconductor processing technology used to prepare SOI (Silicon on Insulator) substrates with specific structures and properties. This technology uses the implantation of oxygen ions in silicon wafers and the heat treatment process to embed a silicon oxide (SiO2) separation layer into the silicon wafer to form an SOI structure.

[0032] Wheatstone bridge: An instrument for measuring resistance, usually consisting of four resistors, two of which are known resistors and the other two are the resistors to be measured. By adjusting the known resistors to balance the bridge, the value of the resistor to be measured can be calculated. Wheatstone bridges are widely used in laboratories and industry to accurately measure resistance.

[0033] ICP etching: ICP (Inductively Coupled Plasma Etching) technology is a commonly used micro-nano processing technology, which is used for precise material etching in semiconductor device manufacturing and micro-nano processing. ICP etching uses high-frequency inductively coupled plasma to accelerate chemical reactions, thereby achieving high-precision etching of materials. This etching technology has the advantages of high speed, high precision, high selectivity and high uniformity.

[0034] RIE etching: RIE (Reactive Ion Etching) technology is a surface processing technology commonly used in semiconductor manufacturing and micro-nano processing to process micro-nano structures. In the RIE etching process, a high-energy ion beam is applied to the surface to cause a chemical reaction of the surface atoms or molecules, thereby achieving the etching of the material. This etching method has the advantages of high processing accuracy, high processing speed, and good surface quality.

[0035] According to an embodiment of the present application, a method for preparing an acoustic sensor chip is provided.

[0036] Figure 1 1 is a flow chart of a method for preparing an acoustic sensor chip according to an embodiment of the present application. Figure 1 As shown, the method comprises the following steps:

[0037] Step S101, implanting oxygen ions into a silicon wafer to obtain a silicon-on-insulator, wherein the silicon-on-insulator consists of a top silicon layer, a buried oxide layer and a substrate silicon.

[0038] Specifically, the SIMOX technology can be used to use ion implantation equipment to vertically bombard the surface of a silicon wafer with high-energy oxygen ions, and then implant the oxygen ions into the silicon wafer. The implanted oxygen ions react chemically with silicon atoms in the silicon wafer at high temperature to form a silicon dioxide film, thereby achieving separation of the silicon wafer from the silicon dioxide film and obtaining silicon-on-insulator.

[0039] It should be noted that silicon on insulator is SOI silicon wafer, which is a sandwich structure consisting of three layers: top silicon, middle buried oxide layer (silicon dioxide insulating layer) and bottom substrate silicon. In acoustic sensor chips, the top silicon has excellent mechanical and electrical properties, so it is used as a material for making beam membrane structure and acoustic sensor resistors; the middle buried oxide layer plays the role of isolating the top silicon and bottom silicon, thereby reducing parasitic capacitance and leakage current, and improving the performance and stability of the device; the bottom substrate silicon plays the role of supporting the entire structure.

[0040] Step S102, determining a preset resistance value of the acoustic resistor in the acoustic chip according to the use requirements of the acoustic chip.

[0041] It should be noted that a sound sensitive resistor is a component that can change its resistance value according to the size of the sound. By adjusting the resistance value of the sound sensitive resistor, the sensitivity and response characteristics of the sound sensitive chip to sound can be adjusted. The preset resistance value is the resistance value predetermined when designing the sound sensitive chip, which is used to achieve the sound detection and processing effect required by the design. According to the specific requirements and design parameters of the sound sensitive chip, different preset resistance values ​​can be selected to achieve different sound detection and processing functions.

[0042] For example, when a sound-sensitive chip is used to switch a light on or off with a voice control, the use requirement of the sound-sensitive chip is that it can accurately sense the sound in the environment and output the corresponding electrical signal. At the same time, the sound-sensitive chip needs to have a high signal-to-noise ratio and sensitivity to ensure accuracy and stability. Under this use requirement, the preset resistance value of the sound-sensitive resistor can be determined by first determining the sound sensitivity range of the sound-sensitive chip according to the actual application scenario, that is, the sound range that needs to be detected, such as 20Hz-20kHz; then, the resistance range of the sound-sensitive resistor is calculated based on the sound sensitivity range, which is usually between tens of kiloohms and hundreds of kiloohms, and finally the preset resistance value of the sound-sensitive resistor in the sound-sensitive chip is determined.

[0043] Step S103, calculating the size parameters of the acoustic resistor according to the preset resistance value, and manufacturing a plurality of acoustic resistors on the top silicon according to the size parameters, wherein the plurality of acoustic resistors constitute a Wheatstone measurement bridge.

[0044] Specifically, after determining the preset resistance value of the acoustic resistor in the acoustic chip, the length, width and other dimensional parameters of the acoustic resistor can be calculated according to the preset resistance value. First, the resistance value of the resistor block per unit area can be determined, and the current upper limit value can be calculated according to the resistance value and the upper limit value of the resistor power. The width value of the acoustic resistor can be determined according to the current upper limit value and the preset current value. At the same time, the length value of the acoustic resistor can be determined according to the preset resistance value, the resistance value of the resistor block and the width value. Finally, the length value and width value can be determined as the dimensional parameters of the acoustic resistor.

[0045] Furthermore, based on the calculated size parameters of the acoustic resistor, multiple acoustic resistors, usually four acoustic resistors, can be made on the top silicon through an ion implantation process. They are connected according to the configuration of a Wheatstone measuring bridge to form a Wheatstone measuring bridge. The four resistors are respectively located on the four arms of the bridge, namely two input arms and two output arms. The bridge is balanced by adjusting the resistance value in the bridge, and then the resistance value of the acoustic resistor is indirectly measured based on the voltage change at both ends of the bridge, thereby further reflecting the sound intensity in the environment.

[0046] Step S104, constructing the top silicon into a beam membrane structure to obtain a sound-sensitive chip.

[0047] Specifically, using ICP etching or other micro-nano processing technologies, a beam-membrane structure with a specific shape and size can be made on the top silicon, thereby obtaining a sound-sensitive chip. In the process of constructing the beam-membrane structure, the sound-sensitive resistor is positioned and integrated on the beam-membrane structure, so that when the sound wave acts on the sound-sensitive chip, it will cause the vibration of the beam-membrane structure, thereby causing the resistance of the sound-sensitive resistor to change. This resistance change will break the equilibrium state of the Wheatstone bridge, thereby generating a voltage difference or current difference at the output end of the bridge, realizing the conversion from sound waves to electrical signals. Since this difference is proportional to the change in resistance value, even if the resistance of the sound-sensitive resistor changes very little, a large output voltage or current change can be generated through the bridge. This amplification effect enables the sound-sensitive chip to detect sound wave signals more sensitively and convert them into electrical signals that are easy to process and transmit.

[0048] It should be noted that in the process of manufacturing the acoustic sensor chip, in addition to the aforementioned manufacturing sequence of first generating the Wheatstone measuring bridge and then manufacturing the beam-membrane structure, the beam-membrane structure can also be manufactured first and then the Wheatstone measuring bridge can be generated, that is, the beam-membrane structure is first manufactured on the top silicon by ICP etching or other techniques, and then the acoustic sensor resistor is generated at a specific position of the beam-membrane structure by photolithography, ion implantation and other process steps to form the Wheatstone measuring bridge. This sequence may require more precise process control to ensure that the acoustic sensor resistor can be accurately integrated at the predetermined position of the beam-membrane structure.

[0049] The method for preparing the acoustic sensor chip provided in the embodiment of the present application is to obtain silicon on insulator by injecting oxygen ions into a silicon wafer, wherein the silicon on insulator is composed of top silicon, buried oxide layer and substrate silicon; determine the preset resistance value of the acoustic resistor in the acoustic sensor chip according to the use requirements of the acoustic sensor chip; calculate the size parameters of the acoustic resistor according to the preset resistance value, and make multiple acoustic resistors on the top silicon according to the size parameters, wherein the multiple acoustic resistors constitute a Wheatstone measurement bridge; construct the top silicon into a beam-membrane structure to obtain the acoustic sensor chip. By using silicon on insulator to make acoustic resistors, construct a Wheatstone measurement bridge and a beam-membrane structure, the conversion and amplification of the acoustic wave signal are realized, and the problems of low sensitivity and poor stability of the traditional acoustic sensor chip in the related art are solved, thereby achieving the effect of improving the sensitivity and accuracy of the acoustic sensor chip.

[0050] Optionally, in the method for preparing the acoustic sensor chip provided in an embodiment of the present application, oxygen ions are implanted into a silicon wafer to obtain silicon on an insulator, including: obtaining a single crystal silicon wafer, and implanting oxygen ions with a dose greater than a preset value into below the surface of the silicon wafer; placing the silicon wafer after the oxygen ion implantation in a high temperature environment for annealing treatment until a silicon dioxide insulating layer of uniform thickness is formed below the surface of the single crystal silicon wafer, thereby obtaining silicon on an insulator.

[0051] It should be noted that the production of silicon on insulator can first obtain a high-quality single-crystal silicon wafer as a substrate, and ensure that the surface of the silicon wafer is smooth and defect-free, and perform necessary cleaning and processing, and then use ion implantation equipment to implant high doses of oxygen ions below the surface of the silicon wafer. The injection depth of the oxygen ions depends on the required buried oxide layer, that is, the thickness of the silicon dioxide insulating layer and the injection energy. During the injection process, the silicon wafer needs to maintain a certain temperature to prevent amorphization.

[0052] Furthermore, the silicon wafer after oxygen ion injection is placed in a high temperature environment for annealing. At high temperature, oxygen ions react chemically with silicon atoms in the silicon wafer to form a silicon dioxide insulating layer. After high temperature annealing, a silicon dioxide insulating layer with uniform thickness is formed below the surface of the silicon wafer. Above the silicon dioxide insulating layer, a layer of well-crystallized silicon is retained as the top silicon layer. The bottom silicon substrate and the top silicon layer are electrically isolated by the silicon dioxide insulating layer. As needed, the silicon on insulator can be further processed and treated, such as polishing, cleaning, etc. After the processing is completed, the silicon on insulator can be used to make acoustic sensitive chips.

[0053] In this embodiment, silicon on insulator is formed by performing oxygen ion implantation and high temperature annealing on the silicon wafer, thereby improving the performance and stability of the acoustic sensor chip and reducing power consumption.

[0054] Optionally, in the preparation method of the sound sensitive chip provided in the embodiment of the present application, calculating the size parameters of the sound sensitive resistor according to the preset resistance value includes: determining the resistance value of the resistance block per unit area, and calculating the current upper limit value according to the resistance value and the resistance power upper limit value; determining the width value of the sound sensitive resistor according to the current upper limit value and the preset current value; determining the length value of the sound sensitive resistor according to the preset resistance value, the resistance value of the resistance block and the width value; and determining the length value and the width value as the size parameters of the sound sensitive resistor.

[0055] It should be noted that in the process of making the acoustic resistor, the length, width and other dimensional parameters of the acoustic resistor can be calculated according to the preset resistance value. Since the larger the resistance, the smaller the output current, the smaller the load resistance affects the bridge circuit change. The resistor block on the silicon wafer is obtained by ion implantation process, so the power consumption of the resistor is required to be as small as possible. When the length and width of the resistor block are equal, the power per unit area of ​​the resistor block can be shown as formula (1):

[0056]

[0057] After transforming formula (1), we get formula (2):

[0058]

[0059] Where P is the power per unit area of ​​the ion implanted resistor block, I is the preset current, R is the resistance of the preset resistor, L is the length of the resistor block, W is the width of the resistor block, and R s is the resistance value of the resistor block per unit area.

[0060] When the resistor block width is fixed to unit 1, the operating current of the resistor block is:

[0061]

[0062] Get the maximum current of the resistor block:

[0063]

[0064] Among them, I wmax is the maximum current per unit area, I max is the maximum current, P max For maximum power, after determining the maximum power and resistance value per unit area of ​​the resistor block, the current upper limit value can be calculated according to the formula (4) of the maximum working current, and then the width value of the resistor block can be calculated according to the current upper limit value and the preset current value. Since the top silicon of the silicon wafer has thickness, considering the actual process requirements, the width design of the resistor block can be appropriately increased based on the calculation result. Finally, combined with the preset resistance value, the resistance value and width value of the resistor block, the length value of the acoustic sensitive resistor can be calculated by formula (2), and the obtained length value and width value are determined as the size parameters of the acoustic sensitive resistor.

[0065] In this embodiment, the size parameters of the acoustic resistor are determined by presetting the resistance value, thereby ensuring the accuracy of manufacturing the acoustic resistor.

[0066] Optionally, in the method for preparing the acoustic sensitive chip provided in the embodiment of the present application, making multiple acoustic sensitive resistors on the top silicon according to size parameters includes: determining the arrangement position of each acoustic sensitive resistor according to the style of the Wheatstone measuring bridge; and injecting ions into the top silicon according to the size parameters through an ion implantation process at each arrangement position to obtain acoustic sensitive resistors.

[0067] It should be noted that after determining the size parameters of the sonic resistor, the sonic resistor can be manufactured on the top silicon according to the size parameters. First, the arrangement position of the sonic resistor is determined according to the style of the Wheatstone bridge (such as a four-arm bridge, etc.). The bridge usually includes four resistors, which are respectively located on the four arms of the bridge, namely two input arms and two output arms. Then, according to the structure and requirements of the bridge, the layout diagram of the bridge is designed on the silicon wafer, including the position and connection method of the sonic resistor.

[0068] Furthermore, the acoustic resistor is made by the ion implantation process. First, the required ions can be designed and prepared, and the ions can be implanted into the top silicon at various arrangement positions of the acoustic resistor according to the size parameters. The desired resistance area can be formed by changing the conductivity of the silicon. After the ion implantation, the substrate silicon can be heat treated to restore its crystal structure and stabilize the resistance value; then a photolithography process is used, that is, a layer of photoresist is coated on the top silicon, and a photolithography machine is used to project the designed layout of the acoustic resistor strip onto the photoresist, and through the development and fixing steps, specific areas on the photoresist are removed or retained to form a photolithography pattern; finally, the RIE etching process can be used to etch the top silicon to produce an acoustic resistor of corresponding size. The RIE process combines chemical reactions and physical bombardment, and can efficiently remove silicon materials that are not protected by the photoresist. By precisely controlling the etching time and gas composition, an acoustic resistor with a specific shape and size is formed.

[0069] Furthermore, multiple acoustic sensitive resistors manufactured in a specific arrangement position can form a Wheatstone measurement bridge, which can be tested to ensure that its performance meets the design requirements, and necessary calibration and adjustment can be performed based on the test results to improve the accuracy and stability of the acoustic sensitive chip.

[0070] In this embodiment, the acoustic sensitive resistor is manufactured by ion implantation and other process technologies, and the Wheatstone measurement bridge composed of the acoustic sensitive resistor is tested and calibrated to ensure the accuracy and stability of the acoustic sensitive chip.

[0071] Optionally, in the method for preparing the acoustic sensor chip provided in the embodiment of the present application, the method further includes: changing the conductivity type of the top silicon to P type and changing the conductivity type of the substrate silicon to N type through a doping process.

[0072] It should be noted that when the doping concentration on the surface of the silicon wafer is higher, the piezoresistance coefficient π value of the silicon wafer is smaller, and the temperature effect is smaller. When selecting silicon wafers, specific requirements can be made on the doping concentration and conductivity type. For N-type silicon wafers, the longitudinal piezoresistance coefficient in the 100 crystal direction is relatively large. When using N-type silicon to make acoustic resistors, the piezoresistance coefficient on N-type silicon is very nonlinear, and in other crystal directions, the piezoresistance coefficient of N-type silicon is relatively small. Therefore, the material of the acoustic resistor can be selected from P-type silicon, and the doping type of the top silicon is determined to be P-type. Considering the process of making the beam membrane structure by ICP etching method, the substrate material SOI silicon wafer crystal direction will be selected. <100> Crystal direction, at the same time, a SOI silicon wafer made by SIMOX process technology is selected, and the silicon substrate is N-type.

[0073] Furthermore, by changing the conductivity type of the top silicon to P type and the conductivity type of the substrate silicon to N type, a PN structure can be formed. The PN structure has different conductivity properties under forward bias and reverse bias, which can make the acoustic sensitive resistor device have bidirectional conductivity, that is, it has different resistance values ​​under different bias conditions. In this way, the resistance value can be adjusted according to the change of the external signal, and the control and amplification functions of the acoustic sensitive resistor device can be realized, thereby ensuring the sensitivity and response performance of the acoustic sensitive resistor device.

[0074] In this embodiment, the conductivity type of the top silicon and the substrate silicon is changed by a doping process to form a PN structure, thereby improving the sensitivity and response performance of the acoustic sensor chip.

[0075] Optionally, in the preparation method of the acoustic sensor chip provided in an embodiment of the present application, constructing the top layer of silicon into a beam-membrane structure includes: using ICP etching technology to make the top layer of silicon into a beam-membrane structure, wherein the acoustic sensor resistor is integrated on the beam-membrane structure so that the resistance of the acoustic sensor resistor changes with the vibration of the beam-membrane structure.

[0076] It should be noted that after making the acoustic resistor and forming the Wheatstone measurement bridge, the top silicon can be constructed into a beam membrane structure. First, the layout of the beam membrane structure of the top silicon can be designed according to the design requirements and dimensional parameters, including the shape, size, position, etc. of the beam; then, photoresist is covered on the surface of the silicon wafer, and a photolithography device is used to form a beam pattern on the photoresist through mask exposure and development; the photoetched silicon wafer is placed in an ICP etching device, and a high-energy ion beam and chemical gas are used to etch the surface of the silicon wafer to form a beam structure; after etching, the silicon wafer is cleaned and the photoresist is removed, and corresponding inspections and tests are performed to verify its performance and quality.

[0077] Furthermore, in the process of manufacturing the beam-membrane structure, the acoustic resistor is integrated on the beam-membrane structure. Therefore, when the sound wave acts on the beam-membrane structure and causes a slight deformation of the beam-membrane structure, this deformation will further affect the acoustic resistor located on the structure, directly causing the resistance value of the acoustic resistor to change. This resistance change can then be detected by the Wheatstone bridge, amplified and converted into a measurable electrical signal output, thereby realizing the conversion from sound waves to electrical signals.

[0078] In this embodiment, the beam-membrane structure is manufactured by ICP etching technology, so that the beam-membrane structure can cooperate with the Wheatstone measurement bridge to complete the detection and conversion of sound waves, thereby improving the sensitivity and accuracy of the acoustic sensor chip.

[0079] Optionally, in the preparation method of the acoustic sensitive chip provided in the embodiment of the present application, determining the preset resistance value of the acoustic sensitive resistor in the acoustic sensitive chip according to the use requirements of the acoustic sensitive chip includes: determining the application scenario of the acoustic sensitive chip, and determining the preset resistance value of each acoustic sensitive resistor of the Wheatstone measurement bridge in the acoustic sensitive chip according to the application scenario, wherein the preset resistance value of each acoustic sensitive resistor of the Wheatstone measurement bridge is the same.

[0080] It should be noted that the acoustic chip can be used to detect and measure sound signals in the environment, so it has many application scenarios, such as: speech recognition, noise monitoring, voice-controlled switches, etc. Different application scenarios have different requirements for the use of acoustic chips. Therefore, the preset resistance values ​​of each acoustic resistor of the Wheatstone measurement bridge in the acoustic chip can be determined according to the requirements of the application scenario, and ensure that the preset resistance values ​​of each acoustic resistor are the same.

[0081] For example, in the application scenario of noise monitoring, the preset resistance value of the acoustic resistor is determined. First, the type of noise to be monitored can be determined, such as environmental noise, mechanical noise, etc., and the noise frequency range to be monitored can be determined according to the requirements of the application scenario. At the same time, the sensitivity requirements of the monitored noise signal can also be determined, such as the high monitoring sensitivity requirements for low-frequency noise; then, according to the above three requirements, a suitable preset resistance value of the acoustic resistor is selected, and its resistance range should be able to cover the frequency range of the monitored noise signal and meet the sensitivity requirements; experimental verification can be performed by selecting several acoustic resistors with different resistance values, and the most suitable preset resistance value of the acoustic resistor can be determined according to the experimental results, and the preset resistance value of the acoustic resistor can be debugged and optimized to ensure that it can achieve the best effect in the specific application scenario.

[0082] This embodiment determines the preset resistance value of the acoustic resistor according to the actual requirements of the application scenario, thereby ensuring the accuracy and sensitivity of the acoustic sensor chip in different application scenarios.

[0083] Figure 2 is a material structure diagram of the acoustic sensor chip provided in the embodiment of the present application, such as Figure 2 As shown, the structure includes:

[0084] The top silicon, located above the buried oxide layer, has excellent mechanical and electrical properties. After multiple process steps, including photolithography, etching, deposition, etc., it can form the structure and circuit of various devices. In the acoustic sensor chip, the top silicon is used for the production and formation of beam membrane structure, acoustic resistor, and Wheatstone measurement bridge through ion implantation process, ICP etching technology and other methods. The top silicon is usually doped to adjust its electrical properties and characteristics.

[0085] The buried oxide layer is a silicon dioxide insulating layer located between the top silicon and the substrate silicon, which is used to isolate the top silicon and the substrate silicon to prevent charge leakage and electron drift. During the manufacturing process, a silicon oxide film can be deposited on the top silicon by chemical vapor deposition and other technologies, and then a uniform silicon oxide layer is formed by annealing and other process steps. The buried oxide layer can protect the top silicon, improve the stability and reliability of the device, and also reduce the capacitance effect and electromagnetic interference.

[0086] Substrate silicon refers to the silicon substrate located below the buried oxide layer, which is used as a base to support the top silicon and buried oxide layer. Substrate silicon is usually doped to adjust its resistivity and conductivity, thereby affecting the sensitivity and performance of the acoustic sensor chip. Substrate silicon can also be used as a reference voltage for the device to stabilize and support the entire device structure.

[0087] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0088] The present application also provides a device for preparing a sound-sensitive chip. It should be noted that the device for preparing a sound-sensitive chip in the present application can be used to execute the method for preparing a sound-sensitive chip provided in the present application. The following is an introduction to the device for preparing a sound-sensitive chip provided in the present application.

[0089] Figure 3 Schematic diagram of a device for preparing an acoustic sensor chip according to an embodiment of the present application. Figure 3 As shown, the device comprises:

[0090] The implantation unit 31 is used to implant oxygen ions into the silicon wafer to obtain silicon-on-insulator, wherein the silicon-on-insulator consists of a top silicon layer, a buried oxide layer and a substrate silicon.

[0091] The determination unit 32 is used to determine the preset resistance value of the acoustic resistor in the acoustic chip according to the use requirements of the acoustic chip.

[0092] The calculation unit 33 is used to calculate the size parameters of the acoustic resistor according to the preset resistance value, and to manufacture a plurality of acoustic resistors on the top silicon according to the size parameters, wherein the plurality of acoustic resistors constitute a Wheatstone measurement bridge.

[0093] The construction unit 34 is used to construct the top silicon layer into a beam membrane structure to obtain a sound-sensitive chip.

[0094] The preparation device of the acoustic chip provided in the embodiment of the present application, injects oxygen ions into the silicon wafer through the injection unit 31 to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, buried oxide layer and substrate silicon; the determination unit 32 determines the preset resistance value of the acoustic resistor in the acoustic chip according to the use requirements of the acoustic chip; the calculation unit 33 calculates the size parameters of the acoustic resistor according to the preset resistance value, and makes a plurality of acoustic resistors on the top silicon according to the size parameters, wherein the plurality of acoustic resistors constitute a Wheatstone measurement bridge; the construction unit 34 constructs the top silicon into a beam-membrane structure to obtain the acoustic chip. By using silicon on insulator to make acoustic resistors, constructing a Wheatstone measurement bridge and a beam-membrane structure, the conversion and amplification of the acoustic wave signal are realized, and the problem of low sensitivity and poor stability of the traditional acoustic chip in the related art is solved, thereby achieving the effect of improving the sensitivity and accuracy of the acoustic chip.

[0095] Optionally, in the preparation device of the acoustic sensitive chip provided in the embodiment of the present application, the injection unit 31 includes: an acquisition module, used to obtain a single crystal silicon wafer, and inject oxygen ions with a dose greater than a preset value into below the surface of the silicon wafer; a processing module, used to place the silicon wafer after the oxygen ion injection in a high temperature environment for annealing treatment until a silicon dioxide insulating layer of uniform thickness is formed below the surface of the single crystal silicon wafer to obtain silicon on insulator.

[0096] Optionally, in the preparation device of the acoustic sensitive chip provided in the embodiment of the present application, the calculation unit 33 includes: a first determination module, used to determine the resistance value of the resistor block per unit area, and calculate the current upper limit value based on the resistance value and the resistance power upper limit value; a second determination module, used to determine the width value of the acoustic sensitive resistor based on the current upper limit value and the preset current value; a third determination module, used to determine the length value of the acoustic sensitive resistor based on the preset resistance value, the resistance value and the width value of the resistor block; a fourth determination module, used to determine the length value and the width value as the size parameters of the acoustic sensitive resistor.

[0097] Optionally, in the preparation device of the acoustic sensitive chip provided in the embodiment of the present application, the calculation unit 33 includes: a fifth determination module, used to determine the arrangement position of each acoustic sensitive resistor according to the pattern of the Wheatstone measurement bridge; an injection module, used to inject ions into the top layer of silicon according to size parameters through an ion implantation process at each arrangement position to obtain an acoustic sensitive resistor.

[0098] Optionally, in the device for preparing the acoustic sensor chip provided in the embodiment of the present application, the method also includes: a changing unit, used to change the conductivity type of the top silicon to P type and the conductivity type of the substrate silicon to N type through a doping process.

[0099] Optionally, in the preparation device of the acoustic sensitive chip provided in the embodiment of the present application, the construction unit 34 includes: a manufacturing module, used to use ICP etching technology to make the top layer of silicon into a beam membrane structure, wherein the acoustic sensitive resistor is integrated on the beam membrane structure so that the resistance value of the acoustic sensitive resistor changes with the vibration of the beam membrane structure.

[0100] Optionally, in the preparation device of the acoustic sensitive chip provided in the embodiment of the present application, the determination unit 32 includes: a sixth determination module, used to determine the application scenario of the acoustic sensitive chip, and determine the preset resistance values ​​of each acoustic sensitive resistor of the Wheatstone measurement bridge in the acoustic sensitive chip according to the application scenario, wherein the preset resistance values ​​of each acoustic sensitive resistor of the Wheatstone measurement bridge are the same.

[0101] The device for preparing the acoustic sensor chip provided in the embodiment of the present application realizes the conversion and amplification of the acoustic wave signal by utilizing silicon on insulator to make the acoustic sensor resistor, constructing the Wheatstone measurement bridge and the beam-diaphragm structure, thereby solving the problem of low sensitivity and poor stability of the traditional acoustic sensor chip in the related technology, and thus achieving the effect of improving the sensitivity and accuracy of the acoustic sensor chip.

[0102] The preparation device of the above-mentioned acoustic sensitive chip includes a processor and a memory. The above-mentioned injection unit 31, determination unit 32, calculation unit 33, construction unit 34, etc. are all stored in the memory as program units, and the processor executes the above-mentioned program units stored in the memory to realize corresponding functions.

[0103] The processor includes a kernel, which retrieves the corresponding program unit from the memory. One or more kernels can be set, and the problem of low sensitivity and poor stability of traditional acoustic chips in related technologies can be solved by adjusting kernel parameters, thereby achieving the effect of improving the sensitivity and accuracy of acoustic chips.

[0104] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0105] An embodiment of the present invention provides a computer-readable storage medium having a program stored thereon, which implements a method for preparing a sound-sensitive chip when the program is executed by a processor.

[0106] An embodiment of the present invention provides a processor, which is used to run a program, wherein the method for preparing a sound-sensitive chip is executed when the program is running.

[0107] Figure 4 is a schematic diagram of an electronic device provided according to an embodiment of the present application, such as Figure 4As shown, an embodiment of the present invention provides an electronic device, the electronic device 40 includes a processor, a memory and a program stored in the memory and can be run on the processor, and the processor implements the following steps when executing the program: oxygen ions are implanted into a silicon wafer to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, buried oxide layer and substrate silicon; the preset resistance value of the acoustic resistor in the acoustic chip is determined according to the use requirements of the acoustic chip; the size parameters of the acoustic resistor are calculated according to the preset resistance value, and multiple acoustic resistors are made on the top silicon according to the size parameters, wherein the multiple acoustic resistors constitute a Wheatstone measurement bridge; the top silicon is constructed as a beam membrane structure to obtain the acoustic chip. The device in this article can be a server, PC, PAD, mobile phone, etc.

[0108] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program having the following method steps: implanting oxygen ions into a silicon wafer to obtain silicon on insulator, wherein the silicon on insulator is composed of top silicon, a buried oxide layer and substrate silicon; determining a preset resistance value of a sonic resistor in the sonic sensor chip according to the use requirements of the sonic sensor chip; calculating size parameters of the sonic resistor according to the preset resistance value, and manufacturing multiple sonic resistors on the top silicon according to the size parameters, wherein the multiple sonic resistors constitute a Wheatstone measurement bridge; constructing the top silicon into a beam-membrane structure to obtain a sonic sensor chip.

[0109] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0110] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0111] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0112] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0113] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0114] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0115] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0116] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0117] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for preparing an acoustic sensor chip, characterized in that: include: Implanting oxygen ions into a silicon wafer to obtain silicon-on-insulator, wherein the silicon-on-insulator consists of a top silicon layer, a buried oxide layer and a substrate silicon; Determining a preset resistance value of a sound sensitive resistor in the sound sensitive chip according to the use requirements of the sound sensitive chip; Calculating the size parameters of the acoustic resistor according to the preset resistance value, and manufacturing a plurality of acoustic resistors on the top silicon according to the size parameters, wherein the plurality of acoustic resistors constitute a Wheatstone measurement bridge; The top silicon layer is constructed into a beam-membrane structure to obtain the acoustic sensor chip.

2. The method according to claim 1, characterized in that: Implanting oxygen ions into a silicon wafer to obtain silicon-on-insulator includes: Obtaining a single crystal silicon wafer, and implanting oxygen ions with a dosage greater than a preset value into the lower surface of the silicon wafer; The silicon wafer after oxygen ion implantation is placed in a high temperature environment for annealing treatment until a silicon dioxide insulating layer with uniform thickness is formed below the surface of the single crystal silicon wafer, thereby obtaining the silicon-on-insulator.

3. The method according to claim 1, characterized in that Calculating the size parameters of the acoustic resistor according to the preset resistance value includes: Determine the resistance value of the resistor block per unit area, and calculate the current upper limit value according to the resistance value and the resistance power upper limit value; Determining a width value of the acoustic sensitive resistor according to the current upper limit value and the preset current value; Determining a length value of the acoustic sensitive resistor according to the preset resistance value, the resistance value of the resistor block and the width value; The length value and the width value are determined as the size parameters of the acoustic resistor.

4. The method according to claim 1, characterized in that Fabricating a plurality of acoustic sensitive resistors on the top silicon according to the size parameters includes: Determining the arrangement positions of the various acoustic resistors according to the pattern of the Wheatstone measurement bridge; Ions are implanted into the top silicon layer at each arrangement position according to the size parameters through an ion implantation process to obtain the acoustic resistor.

5. The method according to claim 1, characterized in that The method further comprises: The conductivity type of the top silicon is changed to P type through a doping process, and the conductivity type of the substrate silicon is changed to N type.

6. The method according to claim 1, characterized in that Building the top silicon into a beam membrane structure includes: The top silicon layer is made into the beam-membrane structure by ICP etching technology, wherein the acoustic resistor is integrated on the beam-membrane structure so that the resistance of the acoustic resistor changes with the vibration of the beam-membrane structure.

7. The method according to claim 1, characterized in that Determining the preset resistance value of the acoustic resistor in the acoustic chip according to the use requirements of the acoustic chip includes: Determine an application scenario of the acoustic chip, and determine a preset resistance value of each acoustic resistor of a Wheatstone measurement bridge in the acoustic chip according to the application scenario, wherein the preset resistance values ​​of each acoustic resistor of the Wheatstone measurement bridge are the same.

8. A device for preparing an acoustic sensor chip, characterized in that: include: An implantation unit, used for implanting oxygen ions into a silicon wafer to obtain silicon-on-insulator, wherein the silicon-on-insulator is composed of a top silicon layer, a buried oxide layer and a substrate silicon; A determination unit, used to determine a preset resistance value of a sound sensitive resistor in the sound sensitive chip according to the use requirements of the sound sensitive chip; A calculation unit, configured to calculate a size parameter of the acoustic resistor according to the preset resistance value, and to manufacture a plurality of acoustic resistors on the top silicon layer according to the size parameter, wherein the plurality of acoustic resistors constitute a Wheatstone measurement bridge; A construction unit is used to construct the top silicon layer into a beam-membrane structure to obtain the acoustic sensor chip.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored executable program, wherein when the executable program is run, the device where the computer-readable storage medium is located is controlled to execute the method for preparing the acoustic sensitive chip according to any one of claims 1 to 7.

10. An electronic device, characterized in that: include: A memory storing an executable program; A processor is used to run the program, wherein when the program is run, the method for preparing the acoustic sensitive chip according to any one of claims 1 to 7 is executed.

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