HEMT biosensor preparation method and HEMT biosensor

Abstract

The invention relates to an HEMT biosensor preparation method and an HEMT biosensor, and the method comprises the steps: preparing a plurality of single HEMT devices on an HEMT epitaxial layer, and forming an HEMT array; the HEMT epitaxial layer comprises a silicon substrate; etching the silicon substrate in the HEMT array to obtain an array film; transferring the array film to the surface of a flexible substrate with a first insulating layer to obtain a flexible HEMT array film; deploying a plurality of electric connection assemblies on the flexible HEMT array thin film, wherein the electric connection assemblies are correspondingly connected with the plurality of single HEMT on the flexible HEMT array thin film; and preparing a plurality of biomolecule recognition elements above the flexible HEMT array film to form the HEMT biosensor. According to the flexible HEMT array biosensor, the problems of insufficient flexibility and limited application range caused by a hard substrate of the HEMT biosensor are solved, so that the performance, the adaptability and the application field of the flexible HEMT array biosensor are remarkably improved, and powerful support is provided for application in the fields of wearable equipment, implantable medical equipment and the like.

Description

Technical Field

[0001] The present application relates to the field of biosensor technology, and in particular to a method for preparing a HEMT biosensor and a HEMT biosensor. Background Art

[0002] In the field of biosensor technology, HEMT (High Electron Mobility Transistor) biosensors have attracted extensive attention due to their unique performance advantages, such as high sensitivity, high response speed, low detection limit and no need for reference electrodes. This type of sensor has great application potential in the fields of medical health, environmental monitoring and biomedical research, and can achieve high-precision and real-time monitoring of biomarkers, providing an important basis for early diagnosis of diseases, treatment monitoring and life science research.

[0003] However, conventional HEMT biosensors are usually fabricated on hard substrates, such as silicon or sapphire substrates. This hard substrate design limits the application scope of HEMT biosensors, especially in wearable and implantable applications. The hard substrate makes it difficult for the sensor to adapt to complex surfaces (such as curved surfaces and irregular shapes), thus affecting its application effect in these fields.

[0004] Currently, no effective solution has been proposed for the problems of insufficient flexibility and limited application range of HEMT biosensors in related technologies due to hard substrates. Summary of the invention

[0005] The embodiments of the present application provide a method for preparing a HEMT biosensor and a HEMT biosensor, so as to at least solve the problem of insufficient flexibility and limited application range of HEMT biosensors in related technologies due to hard substrates.

[0006] In a first aspect, the present application provides a method for preparing a HEMT biosensor, comprising: Preparing a plurality of single HEMT devices on a HEMT epitaxial layer to form a HEMT array; the HEMT epitaxial layer comprises a silicon substrate; Etching the silicon substrate in the HEMT array to obtain an array thin film; Transferring the array film to a surface of a flexible substrate having a first insulating layer to obtain a flexible HEMT array film; Disposing a plurality of electrical connection components on the flexible HEMT array film, wherein the electrical connection components are respectively connected to a plurality of single HEMTs on the flexible HEMT array film; A plurality of biomolecule recognition elements are prepared on the flexible HEMT array film to form the HEMT biosensor.

[0007] In some embodiments, after transferring the array film to a flexible substrate surface with a first insulating layer to obtain a flexible HEMT array film, the method further includes: A second insulating layer is formed above the flexible HEMT array film, wherein the second insulating layer is reserved with a first blank window adapted to the source electrode, the drain electrode and the gate electrode in each of the single HEMTs; the source electrode, the drain electrode and the gate electrode in each of the single HEMTs are connected to the electrical connection component through the first blank window; disposing the electrical connection assembly above the second insulating layer; forming a third insulating layer above the electrical connection component, wherein the third insulating layer reserves a second blank window adapted to the gate electrode in each of the single HEMTs and the electrical connection component connected to each of the single HEMTs; the gate electrode in each of the single HEMTs is connected to the biomolecule recognition element through the second blank window; The biomolecule recognition element is fabricated above each of the gate electrodes to form the HEMT biosensor.

[0008] In some embodiments, before transferring the array film to a flexible substrate surface with a first insulating layer to obtain a flexible HEMT array film, the method further includes: A heat dissipation metal layer is formed on the surface of the flexible substrate, and the heat dissipation metal layer is used to dissipate heat from the flexible HEMT array film; the heat dissipation metal layer is located below the first insulating layer.

[0009] In some embodiments, the method further comprises: Each of the single HEMTs comprises a single epitaxial layer and a source electrode, a drain electrode and a gate electrode; The source electrode is connected to the corresponding first external interface through a first wire; the drain electrode is connected to the corresponding second external interface through a second wire; wherein the electrical connection component includes the first wire and the second wire; Dividing a plurality of functionalized modification regions on the surface of the gate electrode according to the number of the HEMT arrays; The element types of the biomolecule recognition elements are determined; and based on the element types, the biomolecule recognition elements are modified on the corresponding functionalized modification regions.

[0010] In some embodiments, the etching process is performed on the silicon substrate in the HEMT array to obtain an array thin film, including: The silicon substrate of the HEMT array is removed by using a dry etching gas to obtain the array film; the dry etching gas includes at least one of sulfur hexafluoride or xenon fluoride.

[0011] In some embodiments, the etching process is performed on the silicon substrate in the HEMT array to obtain an array thin film, including: Etching the silicon substrate in the HEMT array to obtain a substrate-free thin film; The substrate-free film is cut by laser scribing technology to obtain the array film.

[0012] In some of the embodiments, before preparing a plurality of single HEMT devices on the HEMT epitaxial layer to form a HEMT array, the method further includes: Cleaning HEMT original epitaxial wafer; Based on the preset step sequence and etching depth, the HEMT original epitaxial wafer is etched to obtain the HEMT epitaxial layer.

[0013] In some embodiments, etching the HEMT original epitaxial wafer based on a preset step sequence and etching depth includes: Determine a first layer to be etched from the surface layer to the insulating layer in the original epitaxial wafer, and determine a first step sequence corresponding to the first layer to be etched; based on the first step sequence and the first etching depth, etch a first isolation step from top to bottom on the first layer to be etched; the first isolation step is used for electrical isolation between the single HEMTs; Determine a second layer to be etched from the surface layer to the channel layer in the original epitaxial wafer, and determine a second step sequence corresponding to the second layer to be etched; based on the second step sequence and the second etching depth, etch a second isolation step from top to bottom on the second layer to be etched; the second etching depth is less than the first etching depth; the second isolation step is used to locate the source electrode and the drain electrode corresponding to each of the single HEMTs.

[0014] In a second aspect, the present application provides a HEMT biosensor, comprising: Flexible substrate; A first insulating layer, located on the flexible substrate; A HEMT array film is located on the first insulating layer; the HEMT array film includes a plurality of HEMT arrays; wherein the HEMT array film is formed by etching a silicon substrate in the HEMT array; An electrical connection component is disposed on the array film; each of the HEMT arrays is connected to an external interface of the biosensor through the corresponding electrical connection component; The biomolecule recognition element layer is located on the HEMT array film.

[0015] In a third aspect, an embodiment of the present application provides a method for preparing a probe device, comprising: Using laser cutting technology, sharpening one end of the HEMT biosensor to form a tip protruding outward; the HEMT biosensor is prepared by the preparation method of the HEMT biosensor as described in the first aspect above; The tip is sealed to form the probe device.

[0016] Compared with the related art, the flexible HEMT array biosensor preparation method provided in the embodiment of the present application, by removing the hard substrate and replacing it with a flexible substrate, also provides a probe device preparation method to solve the problem of insufficient flexibility and limited application range of HEMT biosensors caused by the hard substrate, and realizes the high adaptability and biocompatibility of sensors in the fields of wearable and implantable medical devices.

[0017] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings: Figure 1 is a hardware structure block diagram of a HEMT biosensor working terminal according to an embodiment of the present invention; Figure 2 is a flow chart of a method for preparing a HEMT biosensor according to an embodiment of the present application; Figure 3 is a diagram of an isolation step structure of a HEMT epitaxial layer according to an embodiment of the present application; Figure 4 is a schematic diagram of a second isolation step on a HEMT device according to an embodiment of the present application; Figure 5 is a schematic diagram of a first isolation step on a HEMT biosensor according to an embodiment of the present application; Figure 6 It is a schematic diagram of dry etching substrate stripping technology for flexible HEMT array film according to a preferred embodiment of the present application; Figure 7 The flexible HEMT array biosensor according to the preferred embodiment of the present application is Figure 6 A schematic diagram of a longitudinal section at the dotted line position; Figure 8 It is a schematic diagram of dry etching substrate stripping technology for flexible HEMT array film according to a preferred embodiment of the present application; Fig. 9 is a physical picture of a flexible HEMT array film according to a preferred embodiment of the present application; Fig.10 It is a comparison diagram of the output characteristic curves of the flexible HEMT before and after the silicon substrate is removed according to the preferred embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the contents disclosed in the present application, some changes such as design, manufacturing or production based on the technical contents disclosed in the present application are only conventional technical means, and should not be understood as insufficient contents disclosed in the present application.

[0020] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0021] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantity limitation, and may indicate the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product that includes a series of steps or modules (units) or is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or units. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application means greater than or equal to two. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" may mean: A exists alone, A and B exist at the same time, and B exists alone. The terms "first", "second", "third" and the like involved in the present application are merely used to distinguish similar objects and do not represent a specific ordering of the objects.

[0022] The method embodiment provided in this embodiment can be executed in a terminal, a computer or a similar computing device. Taking running on a terminal as an example, Figure 1 FIG. 1 is a hardware structure block diagram of a HEMT biosensor working terminal according to an embodiment of the present invention. Figure 1 As shown, the terminal may include one or more ( Figure 1 Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data. Optionally, the terminal may also include a transmission 106 and an input and output 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0023] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the method for preparing the HEMT biosensor in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, to implement the above method. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the terminal via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0024] Transmission 106 is used to receive or send data via a network. The above-mentioned network specific examples may include a wireless network provided by a communication provider of the terminal. In one example, transmission 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other networks through a base station so as to communicate with the Internet. In one example, transmission 106 can be a radio frequency (Radio Frequency, referred to as RF) module, which is used to communicate with the Internet wirelessly.

[0025] This embodiment provides a method for preparing a HEMT biosensor. Figure 2 is a flow chart of a method for preparing a HEMT biosensor according to an embodiment of the present application, such as Figure 2 As shown, the process includes the following steps: Step S201, preparing a plurality of single HEMT devices on a HEMT epitaxial layer to form a HEMT array; the HEMT epitaxial layer includes a silicon substrate; Among them, a HEMT epitaxial layer including a silicon substrate is provided, and multiple source electrodes, drain electrodes and gate electrodes can be prepared on the surface of the HEMT epitaxial layer through a series of semiconductor processes (such as photolithography, etching, metal deposition, etc.), thereby forming multiple single HEMT devices, which are arranged according to a specific layout to form a HEMT array. The HEMT array generated in this step enables multiple sensor units to work in parallel, thereby improving the detection efficiency and accuracy of biological molecules.

[0026] Step S202, etching the silicon substrate in the HEMT array to obtain an array thin film; Among them, the etching of the silicon substrate in the HEMT array can be done by dry etching technology, such as reactive ion etching (RIE) or inductively coupled plasma etching (ICP). By precisely controlling the etching depth and range, the silicon substrate can be removed while retaining the HEMT epitaxial layer and electrode structure to form an array film. The array film after removing the silicon substrate in this step has better flexibility and bendability, and can adapt to application scenarios with complex curved surfaces and irregular shapes.

[0027] Step S203, transferring the array film to the surface of the flexible substrate with the first insulating layer to obtain a flexible HEMT array film; Among them, the stamp transfer technology or other similar transfer methods can be used to transfer the array film from the original substrate to the surface of the flexible substrate with the first insulating layer; the function of the first insulating layer is to prevent short circuit between the flexible substrate and the HEMT array film. Optionally, the thickness of the flexible substrate is 2μm-100μm, and the flexible substrate is selected from at least one of a polyimide substrate, a polydimethylsiloxane substrate, a SU-8 photolithography negative resist substrate, or a polyparadichlorotoluene substrate; the thickness of the first insulating layer is 5μm-20μm, and the first insulating layer is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photolithography negative resist layer, or a polyparadichlorotoluene layer; the thickness of the flexible HEMT array film 4 is 4μm-6μm, and the flexible HEMT array film includes a HEMT epitaxial layer and a source electrode, a drain electrode, and a gate electrode respectively located above the HEMT epitaxial layer; the flexible HEMT array film after the transfer in this step maintains the original electrical properties and sensing properties, and at the same time has better flexibility and biocompatibility, and is suitable for wearable and implantable applications.

[0028] Step S204, disposing a plurality of electrical connection components on the flexible HEMT array film, wherein the electrical connection components are respectively connected to a plurality of single HEMTs on the flexible HEMT array film; Among them, the metal material of the multiple electrical connection components is selected from at least one of copper, aluminum, platinum, gold, chromium, titanium or nickel. Multiple electrical connection components can be prepared on the flexible HEMT array film by micro-nano processing technology, each electrical connection component includes 2 metal wires, one end of each metal wire is electrically connected to the source electrode of a single flexible HEMT, and the other end is electrically connected to the external interface; one end of the other metal wire is electrically connected to the drain electrode of a single flexible HEMT, and the other end is electrically connected to the external interface. In addition, multiple electrical connection components can be connected to external settings for a multifunctional wireless system integrating electrophysiological signal recording function, chemical drug delivery function or wireless transmission and data transmission function; by controlling the electrical conduction of each metal wire in the multiple electrical connection components, the operating voltage, frequency and time of a single HEMT can be controlled, thereby realizing real-time monitoring of a single specific biological molecule or a single or multiple specific biological molecules in a biological in vitro or in vivo solution. The deployment of the electrical connection components in this step enables the flexible HEMT array film to be connected to an external circuit, realizes signal transmission and processing, and helps to improve the performance and stability of the sensor.

[0029] Step S205 , preparing a plurality of biomolecule recognition elements on the flexible HEMT array film to form a HEMT biosensor.

[0030] Through chemical modification or bioengineering technology, multiple biomolecular recognition elements are prepared above the gate electrode of the flexible HEMT array film. These biomolecular recognition elements can specifically recognize the target biomolecules and convert them into electrical signals for transmission and processing. The preparation of biomolecular recognition elements in this step enables the HEMT biosensor to achieve real-time monitoring and detection of specific biomolecules, and due to the use of flexible HEMT array films and biocompatible materials, the sensor can be suitable for wearable and implantable applications, providing strong support for medical health, environmental monitoring and biomedical research.

[0031] Through the above steps, compared with traditional HEMT sensors that mostly use hard substrates, which limit the flexibility and adaptability of the sensors and make them difficult to be used in scenarios such as wearable devices or implantable medical devices that require bending or fitting complex surfaces, the present application prepares multiple single HEMT devices on the surface of the HEMT epitaxial layer to form a HEMT array, then etches the silicon substrate to obtain an array film, removes the hard silicon substrate, and provides the possibility for subsequent flexible substrate transfer; by transferring the array film to the surface of a flexible substrate with a first insulating layer, a flexible HEMT array film is obtained, thereby realizing the transition from a hard substrate to a flexible substrate, and improving the flexibility and adaptability of the sensor; by forming a HEMT array film on the flexible HEMT array film Deploying multiple electrical connection components ensures that each HEMT device can be well electrically connected to the external circuit, solves the problem of electrical connection and signal transmission, and ensures the stability of the sensor in a bent or stretched state; by preparing multiple biomolecule recognition elements on top of the flexible HEMT array film to form a HEMT biosensor, the multifunctionality of the sensor is achieved, enabling it to detect multiple biomolecules at the same time. Therefore, this application solves the technical problems of insufficient flexibility and limited application range of HEMT biosensors due to hard substrates, which significantly improves the performance, adaptability and application fields of flexible HEMT array biosensors, and provides strong support for applications in wearable devices, implantable medical devices and other fields.

[0032] In some embodiments, after transferring the array film to the surface of a flexible substrate with a first insulating layer to obtain a flexible HEMT array film, the method further comprises: A second insulating layer is formed above the flexible HEMT array film, wherein the second insulating layer is reserved with a first blank window adapted to the source electrode, the drain electrode and the gate electrode in each single HEMT; the source electrode, the drain electrode and the gate electrode in each single HEMT are connected to the electrical connection component through the first blank window; disposing an electrical connection assembly over the second insulating layer; A third insulating layer is formed above the electrical connection component, and the third insulating layer is reserved with a second blank window adapted to the gate electrode in each single HEMT and the electrical connection component connected to each single HEMT; the gate electrode in each single HEMT is connected to the molecular recognition element layer through the second blank window; A biomolecule recognition element is fabricated above each gate electrode to form a HEMT biosensor.

[0033] Among them, a layer of insulating material is deposited on the flexible HEMT array film, and the material of the second insulating layer is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photoresist negative layer or a polyparadichlorotoluene layer, and then a first blank window adapted to the source electrode, the drain electrode and the gate electrode in each single HEMT is formed by photolithography technology, thereby forming a second insulating layer, and the second insulating layer can reduce leakage or short circuit between the flexible HEMT array film and the electrical connection component while ensuring that the source electrode, the drain electrode and the gate electrode are normally electrically connected to the electrical connection component, thereby improving the stability and reliability of the sensor. The source electrode, the drain electrode and the gate electrode are electrically connected to the electrical connection component through metal wires or other conductive materials to ensure that the current can pass smoothly. This connection method enables the sensor to receive and transmit electrical signals, thereby realizing real-time monitoring of biological molecules. A plurality of spaced electrical connection components are formed above the second insulating layer by printing, electroplating or other processes. Each electrical connection component includes two metal wires, which are respectively used to connect the source electrode and the drain electrode. The deployment of the electrical connection components enables the sensor to be connected to an external power supply or a signal processing circuit to achieve signal transmission and processing.

[0034] A layer of insulating material is deposited above the electrical connection component, and the material of the third insulating layer is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photoresist negative resist layer or a polyparadichlorotoluene layer. Then, a second blank window adapted to the gate electrode in each single HEMT and the electrical connection component connected to each single HEMT is formed by photolithography technology, thereby forming a third insulating layer. The third insulating layer can passivate and protect the electrical connection component and the flexible HEMT array film, prevent other positions except the gate electrode position from contacting the molecular recognition element layer, and improve the stability and reliability of the sensor.

[0035] The gate electrode surface is functionalized by chemical or physical methods, and then the molecular recognition elements (such as enzymes, antibodies, cells, etc.) are fixed to the functionalized gate electrode surface. This connection method enables the sensor to specifically recognize the target biological molecules, thereby realizing real-time monitoring of the biological molecules. According to the type of target biological molecules, the corresponding biomolecule recognition elements (such as enzymes, antibodies, cells, etc.) are selected and fixed to the top of the gate electrode by chemical or physical methods. The preparation of biomolecule recognition elements enables the sensor to realize high-sensitivity and high-specificity real-time monitoring of specific biological molecules, providing strong technical support for the fields of medical health, environmental monitoring and biomedical research.

[0036] In some embodiments, before transferring the array film to the surface of a flexible substrate with a first insulating layer to obtain a flexible HEMT array film, the method further comprises: A heat dissipation metal layer is formed on the surface of the flexible substrate, and the heat dissipation metal layer is used to dissipate heat for the flexible HEMT array film; the heat dissipation metal layer is located below the first insulating layer.

[0037] Among them, a metal film is uniformly deposited on the surface of the flexible substrate by physical deposition (such as sputtering, electroplating) or chemical deposition (such as chemical vapor deposition) and other processes. The metal film is the heat dissipation metal layer. Optionally, the thickness of the metal heat dissipation layer is 100nm-5μm, and the metal heat dissipation layer is selected from at least one metal material layer such as copper, gold, and silver. After the heat dissipation metal layer is deposited, a layer of insulating material is deposited on it to form a first insulating layer, so that the heat dissipation metal layer is isolated from the flexible HEMT array film by the first insulating layer, but the heat can still be conducted to the heat dissipation metal layer through the first insulating layer. In this embodiment, the heat dissipation metal layer is provided, which can effectively conduct the heat generated by the flexible HEMT array film during operation to the flexible substrate, and further dissipate the heat through the flexible substrate, thereby maintaining the temperature stability of the flexible HEMT array biosensor and improving the stability and working life of the sensor. Placing the heat dissipation metal layer below the first insulating layer can avoid direct contact between the heat dissipation metal layer and the flexible HEMT array film, prevent possible short circuit problems, and this structure can still maintain the effective heat dissipation effect of the heat dissipation metal layer on the flexible HEMT array film, ensuring the normal operation of the sensor.

[0038] In some embodiments, the method further comprises: Each single HEMT includes a single epitaxial layer and a source electrode, a drain electrode and a gate electrode; The source electrode is connected to the corresponding first external interface through a first wire; the drain electrode is connected to the corresponding second external interface through a second wire; wherein the electrical connection component includes the first wire and the second wire; Dividing the gate electrode surface into multiple functional modification areas according to the number of HEMT arrays; The element types of several biomolecule recognition elements are determined; and based on the element types, the biomolecule recognition elements are modified on corresponding functional modification regions.

[0039] The metal materials of the source electrode and the drain electrode are independently selected from one or more of titanium, aluminum, nickel or gold, and the metal material of the gate electrode is selected from one or more of titanium, nickel, platinum or gold. A single HEMT is composed of a GaN-based HEMT epitaxial layer and a source electrode, a drain electrode and a gate electrode formed on the epitaxial layer. These electrodes are precisely made at corresponding positions of the epitaxial layer through specific process steps, such as photolithography, evaporation or sputtering. This structure enables each HEMT to work independently and have its own source, drain and gate electrodes, thereby enabling independent detection and monitoring of different biological molecules. Each electrical connection component includes two metal wires, namely a first wire and a second wire, which are respectively used to connect the source electrode and the drain electrode to the external interface. The source electrode is connected to the corresponding first external interface through the first wire, and the drain electrode is connected to the corresponding second external interface through the second wire. The first external interface is connected to the corresponding external power supply, and the second external interface is also connected to the corresponding external power supply.

[0040] On the surface of the gate electrode, multiple functionalized modified areas are divided according to the number of HEMT arrays, and biomolecule recognition elements are deployed on the divided functionalized modified areas. These elements are usually prepared by chemical synthesis or bioengineering technology, have specific structures and functions, and can specifically bind to target biomolecules. The element types include modified glucose oxidase elements, modified calcium ion carrier elements, and modified amino acid oxidase elements. For example, glucose oxidase is modified in some areas above the gate, calcium ion carriers are modified in some areas above the gate, and amino acid oxidase is modified in some areas above the gate, and different biomolecules in the solution in vitro or in vivo are detected at the same time. The division of functionalized modified areas enables different HEMTs to correspond to different biomolecule recognition elements respectively, thereby realizing the simultaneous monitoring of multiple specific biomolecules, improving the sensitivity and selectivity of the sensor, and enabling it to more accurately reflect the changes in biomolecules in the body or environment.

[0041] In some embodiments, etching is performed on a silicon substrate in a HEMT array to obtain an array thin film, including: The silicon substrate of the HEMT array is removed by using dry etching gas to obtain an array film; the dry etching gas includes at least one of sulfur hexafluoride or xenon fluoride.

[0042] Wherein, silicone grease, wax or pump oil is coated on a temporary substrate, and a HEMT epitaxial wafer coated with photoresist protection is adsorbed on the temporary substrate, with the silicon substrate facing upward; the dry etching gas is preferably at least one of sulfur hexafluoride or xenon fluoride, and etching is performed by these gases to remove the silicon substrate. Sulfur hexafluoride and xenon fluoride can efficiently remove the silicon substrate while maintaining the integrity and performance of the HEMT epitaxial layer. Using at least one of them for etching can ensure the controllability and accuracy of the etching process, thereby obtaining a high-quality flexible HEMT epitaxial film.

[0043] In some embodiments, etching is performed on a silicon substrate in a HEMT array to obtain an array thin film, including: Etching the silicon substrate in the HEMT array to obtain a substrate-free thin film; The substrate-free film is cut using laser scribing technology to obtain an array film.

[0044] Among them, by using dry etching technology, fluorine-based gases such as sulfur hexafluoride or xenon fluoride are selected to etch the silicon substrate on the back of the HEMT array until it is completely removed, thereby obtaining a substrate-free HEMT epitaxial film. This step realizes the transition from a hard substrate (silicon substrate) to a flexible substrate, providing a basis for the preparation of a flexible HEMT array biosensor. By removing the silicon substrate, the flexibility and adaptability of the sensor are increased. After obtaining the substrate-free HEMT epitaxial film, the film is precisely cut according to the preset pattern and size using laser scribing technology, thereby obtaining multiple independent flexible HEMT array films. The laser scribing technology has the characteristics of high precision, high efficiency and high flexibility, and can achieve precise cutting of the film to ensure the consistency of the size and shape of each flexible HEMT array film; this step also realizes the transition from a large film to multiple independent array films, which provides convenience for subsequent assembly and application. Through laser scribing technology, flexible HEMT array films with different sizes and shapes can be prepared to meet the needs of different application scenarios.

[0045] In some of the embodiments, before preparing a plurality of single HEMT devices on the HEMT epitaxial layer to form a HEMT array, the method further includes: Cleaning HEMT original epitaxial wafer; Based on the preset step sequence and etching depth, the HEMT original epitaxial wafer is etched to obtain a HEMT epitaxial layer.

[0046] Among them, the HEMT original epitaxial wafer is an unprocessed epitaxial wafer. Figure 3 is a diagram of the isolation step structure of the HEMT epitaxial layer according to an embodiment of the present application, such as Figure 3As shown, based on the preset step sequence and etching depth, an AlN nucleation layer, an AlGaN buffer layer, a GaN channel layer, an AlN insertion layer, an AlGaN barrier layer and a GaN cap layer are sequentially deposited on the HEMT original epitaxial wafer through epitaxial growth technology (such as molecular beam epitaxy MBE, metal organic chemical vapor deposition MOCVD, etc.), thereby obtaining a complete HEMT epitaxial layer. The etching of the isolation step in this embodiment helps to achieve electrical isolation between single HEMTs and prevent mutual interference between devices; through precise etching processing, a high-quality HEMT epitaxial layer can be formed to ensure the electrical performance and stability of the device.

[0047] In some embodiments, based on a preset step sequence and etching depth, the HEMT original epitaxial wafer is etched, including: Determine the first layer to be etched from the surface layer to the insulating layer in the original epitaxial wafer, and determine the first step sequence corresponding to the first layer to be etched; based on the first step sequence and the first etching depth, etch the first isolation step from top to bottom on the first layer to be etched; the first isolation step is used for electrical isolation between each single HEMT; A second layer to be etched from the surface layer to the channel layer in the original epitaxial wafer is determined, and a second step sequence corresponding to the second layer to be etched is determined; based on the second step sequence and the second etching depth, a second isolation step is etched from top to bottom on the second layer to be etched; the second etching depth is less than the first etching depth; and the second isolation step is used to locate the source electrode and the drain electrode corresponding to each single HEMT.

[0048] in, Figure 4 is a schematic diagram of a second isolation step on a HEMT device according to an embodiment of the present application, such as Figure 4 As shown, the second step sequence from top to bottom is GaN cap layer, AlGaN barrier layer, AlN insertion layer, GaN channel layer, the second etching depth is 30 nm -60 nm, and the second layer to be etched is from GaN cap layer to GaN channel layer. Similarly, using photoresist as a mask, through photolithography and ICP etching technology, and based on the second step sequence and the second etching depth, a step (Mesa step) from GaN cap layer to GaN channel layer is etched, that is, the second isolation step, which is located below the source electrode and drain electrode of a single HEMT. The second isolation step provides a basis for the subsequent preparation of the source electrode and drain electrode, and provides precise positioning for the preparation of the source electrode and drain electrode. The existence of the step enables the source electrode and drain electrode to contact the GaN channel layer more effectively, thereby improving the current transmission efficiency and improving the performance and stability of the HEMT.

[0049] Figure 5 is a schematic diagram of a first isolation step on a HEMT biosensor according to an embodiment of the present application, such as Figure 5As shown, the first step sequence from top to bottom is GaN cap layer, AlGaN barrier layer, AlN insertion layer, GaN channel layer, AlGaN buffer layer, the first etching depth is 1.5 μm-3 μm, and the first layer to be etched is from GaN cap layer to AlGaN buffer layer. Spin-coat photoresist on the surface of the original HEMT epitaxial wafer as a mask, use photolithography and ICP (inductively coupled plasma) etching technology, and based on the above-mentioned first step sequence and first etching depth, etch an isolation step from GaN cap layer to AlGaN buffer layer on the HEMT epitaxial wafer to form a first isolation step. The purpose of the first isolation step is to achieve electrical isolation between each single HEMT, which helps to prevent current leakage between adjacent HEMTs, thereby improving the accuracy and stability of the biosensor.

[0050] The embodiments of the present application are described and illustrated below through preferred embodiments.

[0051] Figure 6 FIG. 1 is a top view schematic diagram of a flexible HEMT array biosensor according to a preferred embodiment of the present application, as shown in FIG. Figure 6 As shown, the flexible HEMT array biosensor includes: The flexible substrate 1, specifically, in the present invention, has a thickness of 2 μm-100 μm, and the flexible substrate 1 is selected from at least one of a polyimide substrate, a polydimethylsiloxane substrate, a SU-8 photoresist negative resist substrate, or a poly(p-dichlorotoluene) substrate. Such a configuration can be beneficial for further improving the ability of the flexible HEMT array biosensor to adapt to complex curved surfaces and biocompatibility while ensuring the structural strength of the flexible HEMT array biosensor.

[0052] The metal heat dissipation layer 2 is formed on the flexible substrate 1. Specifically, the thickness of the metal heat dissipation layer 2 is 100nm-5μm. The metal heat dissipation layer 2 is selected from at least one metal material layer such as copper, gold, and silver. Such a configuration can ensure that the heat generated by the flexible HEMT array biosensor during operation is effectively dissipated, thereby reducing the influence of the self-heating effect on the HEMT array biosensor accuracy.

[0053] The first insulating layer 3 is formed on the metal heat dissipation layer 2. Specifically, the thickness of the first insulating layer 3 is 5 μm-20 μm. The first insulating layer 3 is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photoresist negative layer or a polyparadichlorotoluene layer. Such a configuration can avoid the short circuit problem on the back side of the flexible HEMT array film 4.

[0054] The flexible HEMT array film 4 is located on the first insulating layer 3. Specifically, the thickness of the flexible HEMT array film 4 is 4 μm-6 μm. The flexible HEMT array film 4 includes a GaN-based HEMT epitaxial layer 41 and a source electrode 42, a drain electrode 43 and a gate electrode 44 respectively located above the GaN-based HEMT epitaxial layer, wherein the source electrode 42 and the drain electrode 43 are used to be electrically connected to an external power supply through a plurality of electrical connection components 6, and the surface of the gate electrode 44 is used to modify a functionalized biomolecule recognition element. With such a configuration, the arrayed flexible HEMT can be used to simultaneously realize continuous and real-time monitoring of multiple biomolecules.

[0055] A second insulating layer 5 is formed on the flexible HEMT array film 4, and only blank windows are left at the positions of the source electrode 42, the drain electrode 43 and the gate electrode 44 of each flexible HEMT. The second insulating layer 5 is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photoresist layer or a polyparadichlorotoluene layer. Such a configuration can ensure that the source electrode 42 and the drain electrode 43 are electrically connected to the multiple electrical connection components 6 in a one-to-one correspondence and normal manner, while reducing leakage or short circuit between the flexible HEMT array film 4 and the multiple electrical connection components 6; A plurality of electrical connection components 6 are arranged between the second insulating layer 5 and the third insulating layer 7, each of the electrical connection components comprises two metal wires, one end of each metal wire is electrically connected to the source electrode of a single flexible HEMT, and the second end is electrically connected to an external power supply; one end of another metal wire is electrically connected to the drain electrode of the single flexible HEMT, and the second end is electrically connected to the external power supply; so as to drive the flexible HEMT to work normally.

[0056] The third insulating layer 7, the second insulating layer 5 is formed above the multiple electrical connection components 6, and a blank window is left at the position of each flexible HEMT gate electrode 44 and the pin position of the multiple electrical connection components 6. The third insulating layer 7 is selected from at least one of a polyimide layer, a polydimethylsiloxane layer, a SU-8 photoresist negative layer or a polyparadichlorotoluene layer. In this way, the multiple electrical connection components 6 and the flexible HEMT array film 4 can be passivated and protected to prevent other positions except the gate electrode 44 from contacting the molecular recognition element layer; The biomolecule recognition element layer 8 is formed above the gate electrode 44. When the concentration of the specific biomolecules combined with the biomolecule recognition element layer 8 changes, the charge on the surface of the sensing area will change, which will in turn cause the change of the HEMT current signal, thereby achieving the purpose of real-time monitoring of the concentration of the specific biomolecules; Figure 7 The flexible HEMT array biosensor according to the preferred embodiment of the present application is Figure 6 The longitudinal section diagram at the dotted line position is as follows: Figure 7 As shown, above the gate electrode 44, different functional modification areas can be divided according to the number of flexible HEMT arrays, such as modifying glucose oxidase in some areas above the gate, modifying calcium ion carriers in some areas above the gate, and modifying amino acid oxidase in some areas above the gate, so as to simultaneously detect different biological molecules in in vitro or in vivo solutions.

[0057] In addition, the materials and dimensions of each layer are as follows: The metal material of the metal heat dissipation layer 2 is selected from at least one of copper, aluminum, silver or gold.

[0058] The metal materials of the source electrode 42 and the drain electrode 43 are independently selected from one or more of titanium, aluminum, nickel or gold.

[0059] The metal material of the gate electrode 44 is selected from one or more of titanium, nickel, platinum, or gold.

[0060] The metal material of the plurality of electrical connection components 6 is selected from at least one of copper, aluminum, platinum, gold, chromium, titanium or nickel.

[0061] Optionally, the area of ​​a single HEMT in the flexible HEMT array film 4 is (50×100) μm 2 - (150 × 300) μm 2 ; The area of ​​the source electrode 42 on each single HEMT is (10×50) μm 2 - (50 × 150) μm 2 ; The area of ​​the drain electrode 43 on each single HEMT is (10×50) μm 2 - (50 × 150) μm 2 The area of ​​the gate electrode 44 on each single HEMT is the strip gate area (2×50) μm 2 - (20 × 150) μm 2 and the area of ​​the extended gate (45×45) μm 2 - (145 × 145) μm 2 of superposition.

[0062] Optionally, in the flexible HEMT array biosensor, the distance between two adjacent flexible HEMTs is 50-200 μm.

[0063] It should be noted that in this preferred embodiment, the pins of the plurality of electrical connection components 6 can be connected to external devices, and are used to integrate a multifunctional wireless system with electrophysiological signal recording function, chemical drug delivery function, or wireless transmission and data transmission function. By controlling the electrical conduction of each metal wire in the plurality of electrical connection components 6, the operating voltage, frequency, and time of a single flexible HEMT can be controlled, thereby achieving real-time monitoring of a single specific biomolecule or a single or multiple specific biomolecules in a solution in vitro or in vivo.

[0064] Considering that in biosensing applications, the area of ​​the gate electrode used for modification of the biomolecule recognition element layer is one of the main factors determining the sensing ability of the target biomolecule, in this preferred embodiment, the design of the gate electrode is not limited to rectangle, square or circle, and the area of ​​each gate can also be individually designed according to the type of biomolecule to be detected.

[0065] The method for preparing a flexible HEMT array biosensor in a preferred embodiment of the present application comprises the following steps: S1, etching an isolation step from the GaN cap layer to the AlGaN buffer layer in the GaN-based HEMT epitaxial layer from top to bottom; S2, etching a step from the GaN cap layer to the GaN channel layer on the GaN-based HEMT epitaxial layer from top to bottom; Specifically, a GaN-based HEMT epitaxial wafer is provided, wherein the GaN-based LED epitaxial wafer includes a GaN-based HEMT epitaxial layer, which includes a silicon substrate, an AlN nucleation layer, an AlGaN buffer layer, a GaN channel layer, an AlN insertion layer, an AlGaN barrier layer and a GaN cap layer in order from bottom to top; Spin-coat photoresist on the surface of GaN-based HEMT epitaxial wafer as a mask, and use photolithography and ICP (inductively coupled plasma) etching technology to etch isolation steps from the GaN cap layer to the AlGaN buffer layer on the HEMT epitaxial wafer for electrical isolation of a single HEMT. The etching depth is about 1.5μm-3μm; Figure 8 FIG. 1 is a schematic diagram of a dry etching substrate stripping technique for a flexible HEMT array film according to a preferred embodiment of the present application. Figure 8 As shown, the second time, photoresist is used as a mask to etch a step (Mesa step) from the GaN cap layer to the GaN channel layer through photolithography and ICP etching technology, with an etching depth of about 30 nm-60 nm.

[0066] S3, preparing a source electrode, a drain electrode and a gate electrode on the surface of the HEMT epitaxial layer to obtain a HEMT array consisting of a plurality of HEMTs; Specifically, a third time, a photoresist is used as a mask to deposit metal on the GaN-based HEMT epitaxial wafer, and a source electrode 42 and a drain electrode 43 are prepared at the step by a lift-off process; In a rapid annealing furnace, the source electrode 42 and the drain electrode 43 are subjected to high temperature annealing, so that the AlGaN barrier layer forms an ohmic contact with the source electrode 42 and the drain electrode 43, and the source electrode 42 and the drain electrode 43 are at the same height and have a thickness of 100 nm to 400 nm; The fourth time, a metal is deposited on the GaN-based HEMT epitaxial wafer using the photoresist as a mask, and a gate electrode 44 with a thickness of 100 nm to 200 nm is prepared on the GaN cap layer and the GaN channel layer by a lift-off process.

[0067] S4, removing the silicon substrate on the back of the HEMT array to obtain a flexible HEMT array film; Specifically, silicone grease or pump oil is coated on the temporary substrate, and the HEMT epitaxial wafer coated with photoresist protection is adsorbed on the temporary substrate, with the silicon substrate 9 facing upward, and the silicon substrate 9 is removed by dry etching technology to prepare a flexible HEMT epitaxial film, and the dry etching gas is preferably at least one of sulfur hexafluoride or xenon fluoride; After the flexible HEMT epitaxial film is adsorbed by a hard substrate with a polyimide film, the photoresist on the surface of the flexible HEMT epitaxial film is removed in an organic solvent and silicone grease or pump oil is applied; The flexible HEMT epitaxial film is cut into a plurality of flexible HEMT array films 4 using laser scribing technology.

[0068] S5, transferring the flexible HEMT array film to the surface of the flexible substrate with the first insulating layer and the metal heat dissipation layer; Specifically, the flexible HEMT array film 4 is transferred to the surface of the flexible substrate 1 with the first insulating layer 3 and the metal heat dissipation layer 2 by using a polyimide stamp and a two-dimensional mobile transfer platform.

[0069] S6, forming a second insulating layer above the HEMT array film; S7, forming a plurality of spaced electrical connection components on the second insulating layer, wherein the source electrode and the drain electrode are electrically connected to corresponding electrical connection components respectively; Specifically, the second insulating layer 5 is prepared by using the photoresist as a mask for the fifth time, leaving a blank window without the second insulating layer 5 above the source electrode 42, the drain electrode 43 and the gate electrode 44 of each flexible HEMT in the flexible HEMT array film 4. The material of the second insulating layer 5 is preferably SU-8 photoresist negative resist; Metal is deposited on the second insulating layer 5, and a photoresist is used as a mask for the sixth time to prepare a plurality of patterned electrical connection components 6 by wet etching or dry etching technology, wherein the metal layer can be dry-etched by processes such as reactive plasma etching (RIE) and plasma etching (ICP), or the metal layer can be wet-etched by a metal etching solution.

[0070] S8, forming a third insulating layer above the plurality of electrical connection components; S9, modifying different biomolecule recognition elements (including enzymes, antibodies, cells, tissues, nucleic acids, etc.) above different gate electrodes.

[0071] Specifically, the third insulating layer 7 is prepared on the plurality of electrical connection components by using the photoresist as a mask for the seventh time, and a blank window without the second insulating layer 5 is left above the gate electrode 44 position of each flexible HEMT in the flexible HEMT array film 4 and the pin positions of the plurality of electrical connection components 6. The material of the third insulating layer 7 is preferably SU-8 photoresist negative resist; The surface of the gate electrode 44 of each flexible HEMT is functionalized by chemical or physical methods, and different biomolecule recognition elements (including enzymes, antibodies, cells, tissues, nucleic acids, etc.) are fixed to the functionalized surface of the gate electrode 44 in multiple regions; The sensing area on the surface of the gate electrode 44 is placed in a phosphate buffered saline solution with a bovine serum albumin concentration of 1% (V / V) to block the active sites of the unmodified biomolecule recognition elements.

[0072] The method for preparing the flexible HEMT array biosensor of this preferred embodiment enables the prepared flexible HEMT array biosensor to have the characteristics of bendability, thin thickness, high sensitivity, low power consumption and real-time monitoring, and can simultaneously meet the flexibility, safety, stability and biocompatibility requirements of wearable and implantable applications.

[0073] This preferred embodiment includes the following two applications: (1) Fig. 9 This is a physical picture of a flexible HEMT array film according to a preferred embodiment of the present application. The physical picture of a flexible HEMT array film sample prepared by using sulfur hexafluoride gas dry etching and stamp transfer technology is as follows Fig. 9 As shown in the figure, the area of ​​the flexible HEMT array film sample is 2×2 cm 2 The area of ​​a single flexible HEMT is (100×240) μm 2 The source and drain electrodes on a single flexible HEMT have an area of ​​(50×100) μm 2 , the distance between the source electrode and the drain electrode is 70 μm, and the area of ​​the gate electrode is (4 × 100) μm 2Stripe gate and (100×120) μm 2 The area of ​​the extended gate is superimposed; thickened electrodes are prepared above the source electrode and the drain electrode, and the area of ​​the thickened electrode is (150×500) μm 2 ; The distance between two adjacent flexible HEMTs is 200μm; After the silicon substrate is removed by dry etching, the GaN-based flexible HEMT array film is transparent and has a thickness of about 4μm, making it easier to adhere to complex surfaces and has good biocompatibility; Fig.10 : is a comparison diagram of the output characteristic curves of the flexible HEMT before and after the silicon substrate is removed according to the preferred embodiment of the present application. The output characteristic curves of the flexible HEMT array thin film sample before and after the substrate is removed are as follows: Fig.10 As shown in the figure, after removing the silicon substrate, the stress of the epitaxial layer changes, and the superimposed dry etching technology may cause some process damage, which causes a slight decrease in the current between the source electrode and the drain electrode of the flexible HEMT without a silicon substrate. However, the current still maintains good linearity within the operating voltage range.

[0074] After modifying the gate electrode surface of the flexible HEMT array film with different biomolecule recognition elements, such as potassium ion carriers, calcium ion carriers or carriers bound to lactic acid, the flexible substrate of the flexible HEMT array film is fixed on the sweat strip. The specific detection of electrolytes and lactic acid in sweat can be achieved by recording the current changes of the flexible HEMT.

[0075] (2) The difference between Application 2 and Application 1 is that the gate electrode surface of the flexible HEMT array film is modified with glucose oxidase, potassium ion carrier and calcium ion carrier respectively, and the tip of the flexible HEMT array biosensor is sharpened by laser cutting technology; polydimethylsiloxane material is coated to form a transparent encapsulation layer to prepare an implantable probe device; By placing an implantable probe made of flexible HEMT array film at the target location in the body, continuous and real-time detection of small molecule metabolites and electrolytes in tissue fluid can be achieved.

[0076] This embodiment also provides a HEMT biosensor, comprising: Flexible substrate; A first insulating layer, located on the flexible substrate; A HEMT array film is located on the first insulating layer; the HEMT array film includes a plurality of HEMT arrays; wherein the HEMT array film is formed by etching a silicon substrate in the HEMT array; The electrical connection component is disposed on the array film; each HEMT array is connected to the external interface of the biosensor through the corresponding electrical connection component; The biomolecule recognition element layer is located on the HEMT array film.

[0077] This embodiment also provides a method for preparing a probe device, comprising: Using laser cutting technology, sharpen one end of the HEMT biosensor to form a tip protruding outward; the HEMT biosensor is prepared by any one of the preparation methods of the HEMT biosensor in the above embodiments; The tip is sealed to form a probe device.

[0078] Among them, the tip of the flexible HEMT array biosensor is sharpened by laser cutting technology; polydimethylsiloxane material is coated to form a transparent encapsulation layer to prepare an implantable probe device. The implantable probe prepared by the flexible HEMT array film is placed at the target position in the body, so that continuous and real-time detection of small molecule metabolites and electrolytes in the tissue fluid can be achieved. The design of the tip shape of this probe device enables the sensor to contact the biological tissue or fluid being measured more deeply, thereby improving the accuracy and sensitivity of the measurement. By forming the tip and performing the sealing layer treatment, the HEMT biosensor can be more conveniently used in various biological measurement scenarios that require high precision, high sensitivity and high biocompatibility. For example, in the fields of implantable medical devices, biological monitoring systems and clinical diagnosis, this probe device will have broad application prospects.

[0079] Those skilled in the art should understand that the technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for preparing a HEMT biosensor, characterized in that: include: Fabricating a plurality of single HEMT devices on the HEMT epitaxial layer to form a HEMT array; The HEMT epitaxial layer includes a silicon substrate; Etching the silicon substrate in the HEMT array to obtain an array thin film; Transferring the array film to a surface of a flexible substrate having a first insulating layer to obtain a flexible HEMT array film; Disposing a plurality of electrical connection components on the flexible HEMT array film, wherein the electrical connection components are respectively connected to a plurality of single HEMTs on the flexible HEMT array film; A plurality of biomolecule recognition elements are prepared on the flexible HEMT array film to form the HEMT biosensor.

2. The method for preparing a HEMT biosensor according to claim 1, characterized in that: After transferring the array film to the surface of the flexible substrate with the first insulating layer to obtain a flexible HEMT array film, the method further includes: A second insulating layer is formed above the flexible HEMT array film, wherein the second insulating layer is reserved with a first blank window adapted to the source electrode, the drain electrode and the gate electrode in each of the single HEMTs; the source electrode, the drain electrode and the gate electrode in each of the single HEMTs are connected to the electrical connection component through the first blank window; disposing the electrical connection assembly above the second insulating layer; forming a third insulating layer above the electrical connection component, wherein the third insulating layer reserves a second blank window adapted to the gate electrode in each of the single HEMTs and the electrical connection component connected to each of the single HEMTs; the gate electrode in each of the single HEMTs is connected to the biomolecule recognition element through the second blank window; The biomolecule recognition element is fabricated above each of the gate electrodes to form the HEMT biosensor.

3. The method for preparing a HEMT biosensor according to claim 1, characterized in that: Before transferring the array film to the surface of the flexible substrate with the first insulating layer to obtain the flexible HEMT array film, the method further comprises: A heat dissipation metal layer is formed on the surface of the flexible substrate, and the heat dissipation metal layer is used to dissipate heat from the flexible HEMT array film; the heat dissipation metal layer is located below the first insulating layer.

4. The method for preparing a HEMT biosensor according to claim 1, characterized in that: The method further comprises: Each of the single HEMTs comprises a single epitaxial layer and a source electrode, a drain electrode and a gate electrode; The source electrode is connected to the corresponding first external interface through a first wire; the drain electrode is connected to the corresponding second external interface through a second wire; wherein the electrical connection component includes the first wire and the second wire; Dividing a plurality of functionalized modification regions on the surface of the gate electrode according to the number of the HEMT arrays; The element types of the biomolecule recognition elements are determined; and based on the element types, the biomolecule recognition elements are modified on the corresponding functionalized modification regions.

5. The method for preparing a HEMT biosensor according to claim 1, characterized in that: The etching process is performed on the silicon substrate in the HEMT array to obtain an array thin film, comprising: The silicon substrate of the HEMT array is removed by using a dry etching gas to obtain the array film; the dry etching gas includes at least one of sulfur hexafluoride or xenon fluoride.

6. The method for preparing a HEMT biosensor according to claim 1, characterized in that: The etching process is performed on the silicon substrate in the HEMT array to obtain an array thin film, comprising: Etching the silicon substrate in the HEMT array to obtain a substrate-free thin film; The substrate-free film is cut by laser scribing technology to obtain the array film.

7. The method for preparing a HEMT biosensor according to claim 1, characterized in that: Before preparing a plurality of single HEMT devices on the HEMT epitaxial layer to form a HEMT array, the method further includes: Cleaning HEMT original epitaxial wafer; Based on the preset step sequence and etching depth, the HEMT epitaxial wafer is etched to obtain the HEMT epitaxial layer.

8. The method for preparing a HEMT biosensor according to claim 7, characterized in that: The etching process is performed on the HEMT original epitaxial wafer based on the preset step sequence and etching depth, including: Determine a first layer to be etched from the surface layer to the insulating layer in the original epitaxial wafer, and determine a first step sequence corresponding to the first layer to be etched; based on the first step sequence and the first etching depth, etch a first isolation step from top to bottom on the first layer to be etched; the first isolation step is used for electrical isolation between the single HEMTs; Determine a second layer to be etched from the surface layer to the channel layer in the original epitaxial wafer, and determine a second step sequence corresponding to the second layer to be etched; based on the second step sequence and the second etching depth, etch a second isolation step from top to bottom on the second layer to be etched; the second etching depth is less than the first etching depth; the second isolation step is used to locate the source electrode and the drain electrode corresponding to each of the single HEMTs.

9. A HEMT biosensor, characterized in that: include: Flexible substrate; A first insulating layer, located on the flexible substrate; A HEMT array film, located on the first insulating layer; The HEMT array film includes a plurality of HEMT arrays; wherein the HEMT array film is formed by etching a silicon substrate in the HEMT array; An electrical connection component is disposed on the array film; each of the HEMT arrays is connected to an external interface of the biosensor through the corresponding electrical connection component; The biomolecule recognition element layer is located on the HEMT array film.

10. A method for preparing a probe device, characterized in that: include: Using laser cutting technology, one end of the HEMT biosensor is sharpened to form a tip protruding outward; The HEMT biosensor is prepared by the HEMT biosensor preparation method according to any one of claims 1 to 8; The tip is sealed to form the probe device.

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