Carbon nanotube field effect transistor with rapid temperature control based on thermoelectric device and manufacturing method

Abstract

The present invention relates to the research and development and application of semiconductor devices, specifically a carbon nanotube field effect transistor based on thermoelectric devices with rapid temperature control and a manufacturing method. The carbon nanotube field effect transistor includes a substrate, a titanium / gold source and drain electrode in contact with a channel, a hafnium oxide dielectric layer, and a stacked titanium / gold gate electrode located on the hafnium oxide dielectric layer. The substrate is a bottom-up silicon dioxide / heavily doped P-type silicon wafer / silicon dioxide combined structure, the channel is a single-walled carbon nanotube channel prepared by water bath heating deposition, the gate region is above the channel, the bottom-up structure is a hafnium oxide dielectric layer and a gate electrode in sequence, and the source and drain electrodes and the gate electrode are a bottom-up stacked composite structure of titanium / gold. The present invention proposes for the first time a method for controlling the performance of a carbon nanotube field effect transistor based on thermoelectric temperature control technology, which can effectively characterize the impact of ambient temperature changes on the performance of the carbon nanotube field effect transistor and achieve precise control of the device temperature.

Description

Technical Field

[0001] The present invention relates to the research, development and application fields of semiconductor devices, and in particular to a fast temperature-controlled carbon nanotube field effect transistor based on a thermoelectric device and a manufacturing method thereof. Background Art

[0002] Field effect transistor, as a semiconductor device, its core mechanism is to use the electric field effect of the input circuit to accurately control the current flow direction of the output circuit. Its conduction process only depends on the majority carriers inside the semiconductor, so it is also called unipolar transistor. This technology has been widely used in current circuit systems.

[0003] Carbon nanotube field effect transistors (CNTFETs) have shown great potential in the electronics field due to their advantages of small size, high speed, low power consumption, and high reliability, and are expected to become the core technology in the next generation of integrated circuits. However, with the increasing integration of electronic devices, the corresponding device size has further shrunk, which directly leads to an increase in power density and an increase in operating temperature. In addition, with the diversification trend of the application environment of electronic devices, changes in actual ambient temperature have an important impact on device performance. In order to effectively enhance the stability of carbon nanotube-based devices, broaden their application scope, and further optimize energy efficiency, it is particularly important to deeply explore the intrinsic mechanism of the influence of temperature on CNTFET performance.

[0004] Traditional temperature control methods, such as Thomson and Stirling temperature control platforms, are widely used in various temperature control fields, but they have obvious shortcomings in terms of temperature control efficiency, moving parts volume and noise control. Among them, the Thomson temperature control platform requires the replacement of gas cylinders with large moving parts, and the Stirling temperature control platform needs to generate heat through the compression and expansion of gas. The noise disturbance generated in this process often has an adverse effect on the performance test of transistors.

[0005] In recent years, thermoelectric temperature control technology based on the Peltier effect can convert electrical energy into thermal energy, and achieve continuous and high-precision control of temperature by adjusting the working voltage and current. At the same time, thermoelectric devices also have the advantages of fast response speed, simple structure, no noise disturbance and low maintenance. These advantages enable them to show better temperature control performance in the process of integration and optimization with electronic devices. Based on this, thermoelectric devices can achieve accurate, fast and noise-free temperature control of CNTFET, and then conduct more accurate testing and characterization of the electrical performance of CNTFET under different temperature environments, which is of great significance for in-depth exploration of the application potential of CNTFET in various fields. Summary of the invention

[0006] The purpose of the present invention is to propose a fast temperature-controlled carbon nanotube field effect transistor based on thermoelectric devices and a manufacturing method, which can achieve accurate and fast temperature control of CNTFET by integrating thermoelectric devices efficiently in an atmospheric environment, and then conduct in-depth research on the evolution of its electrical performance in a wide temperature range. Specifically, we can observe the reversible polarity transition phenomenon of CNTFET in different temperature ranges, and accurately measure key electrical performance parameters including transfer characteristic curve, threshold voltage, subthreshold swing, current switching ratio and transconductance, which are of great significance for evaluating the performance of CNTFET and expanding its application areas.

[0007] The technical solution of the present invention:

[0008] A fast temperature-controlled carbon nanotube field effect transistor based on a thermoelectric device comprises a substrate, a titanium / gold source-drain electrode in contact with a channel, a hafnium oxide dielectric layer, and a stacked titanium / gold gate electrode located on the hafnium oxide dielectric layer. The overall structure is: silicon dioxide / heavily doped P-type silicon wafer / silicon dioxide / titanium / gold / semiconductor carbon nanotube / hafnium oxide / titanium / gold, a bottom-up stacked composite structure, the substrate is a bottom-up silicon dioxide / heavily doped P-type silicon wafer / silicon dioxide combined structure, the channel is a single-walled carbon nanotube channel deposited by water bath heating, the channel is a gate region, and the gate region has a bottom-up structure of a hafnium oxide dielectric layer and a gate electrode.

[0009] The carbon nanotube field effect transistor with rapid temperature control based on thermoelectric devices is characterized in that the thermoelectric device is mounted under the substrate of the carbon nanotube field effect transistor through phase change thermal conductive material, so that the thermoelectric device and the carbon nanotube field effect transistor are connected through the phase change thermal conductive material; the thermoelectric device is connected to an external DC power supply, and the temperature of the carbon nanotube field effect transistor is regulated based on the Peltier effect; the thermoelectric device includes a metal thermal conductive substrate on the top and bottom, and an N-type and P-type semiconductor array in the middle of the metal thermal conductive substrate, and the basic element of the thermoelectric device is composed of a metal thermal conductive substrate connecting two thermoelectric legs, and the thermoelectric leg materials are respectively made of P-type semiconductor and N-type semiconductor, which are under the substrate of the carbon nanotube field effect transistor.

[0010] The method for manufacturing a carbon nanotube field effect transistor with rapid temperature control based on a thermoelectric device comprises the following steps:

[0011] (1) The substrate is ultrasonically cleaned with acetone and isopropanol to remove surface impurities, and then further cleaned with an oxygen plasma cleaner to ensure that the substrate is clean.

[0012] (2) Using photolithography technology, a photoresist mask layer is accurately formed on the substrate. The maximum effective range of the mask layer is a 2 cm × 2 cm exposure area. The required source and drain electrode deposition areas are exposed on the substrate. Titanium / gold stacked metal electrodes are prepared in the specified areas by vacuum electron beam evaporation technology to construct the source and drain electrodes of the transistor.

[0013] (3) After the Primer photoresist is evenly spin-coated on the substrate, it is immersed in the carbon nanotube solution after ultrasonic dispersion treatment, and the carbon nanotubes are deposited on the substrate by water bath heating to form a transistor channel layer;

[0014] (4) Using oxygen plasma cleaning technology and photolithography technology, firstly, a photoresist mask layer is precisely constructed on the substrate where the carbon nanotube channel has been deposited through photolithography. This step is to pattern out the channel areas that need special protection. Then, using advanced oxygen plasma cleaning technology, the parts other than the source and drain metal electrodes are precisely processed to effectively remove the redundant carbon nanotube film that may cause interference.

[0015] (5) Using atomic layer deposition technology, a hafnium oxide dielectric layer is evenly covered on the carbon nanotube channel to provide an insulating foundation for subsequent gate electrode fabrication;

[0016] (6) using photolithography technology to expose the required gate electrode evaporation area on the hafnium oxide dielectric layer, and using vacuum electron beam evaporation technology to prepare a titanium / gold gate electrode in close contact with the hafnium oxide dielectric layer;

[0017] (7) Using photolithography technology to prepare a photoresist mask layer, exposing the required hafnium oxide etching area to expose the titanium / gold source and drain metal electrodes in contact with the carbon nanotube channel and the substrate, and using reactive ion etching technology with carbon tetrafluoride as the reaction gas to accurately etch the hafnium oxide, ultimately obtaining a structurally complete carbon nanotube field effect transistor array;

[0018] (8) Construct a thermoelectric device compatible with carbon nanotube field effect transistors. Spray acetone and isopropyl alcohol on the surface of the thermoelectric device to remove surface impurities. Then, adhere a phase change thermal conductive material to the surface of the thermoelectric device and tightly adhere the substrate of the transistor to the surface of the phase change thermal conductive material. By applying an external DC power supply, the surface temperature of the thermoelectric device can be precisely controlled, thereby flexibly adjusting the operating temperature of the transistor.

[0019] The method for manufacturing a carbon nanotube field effect transistor with rapid temperature control based on a thermoelectric device, in step (1), the ultrasonic cleaning frequency of the acetone and isopropanol used is 40 Hz, the power is 100 W, and the cleaning is performed twice for five minutes each; the oxygen plasma cleaning time is 10 min, the oxygen flow rate is 180 sccm, and the power is 200 W.

[0020] In the method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control, in step (2) and step (6), an electron beam evaporator is used to evaporate the top gate electrode and the source and drain electrodes at both ends, and the thickness of the Ti layer ranges from 5 to 6 nm, and the thickness of the Au layer ranges from 50 to 51 nm.

[0021] The method for manufacturing a carbon nanotube field effect transistor with rapid temperature control based on a thermoelectric device, in step (3), carbon nanotubes and toluene are mixed in proportion, and the carbon nanotube bundles and insoluble substances are removed by ultrasonic dispersion and centrifugal purification to obtain a semiconductor carbon nanotube solution, and the supernatant is collected as a channel material, and the carbon nanotube solution is ultrasonically treated at an ultrasonic frequency of 40 Hz and a power of 100 W, and the carbon nanotube solution after ultrasonic oscillation dispersion is transferred to a culture dish;

[0022] During the deposition of the carbon nanotube film, the cleaned silicon substrate is first heated to 180°C on a hot plate and baked for 30 minutes to remove moisture from the substrate. In order to make the carbon nanotubes better adsorbed on the substrate and evenly dispersed, the Primer primer is spin-coated on the surface of the substrate by a coater, and then baked on a hot plate at 105°C for 2 minutes; the baked substrate is immersed in a culture dish of the carbon nanotube solution dispersed by ultrasonic vibration, and the culture dish is placed in a 60°C water bath. The liquid level of deionized water in the water bath just exceeds the liquid level of the carbon nanotube solution in the culture dish. After two and a half hours, the deposition of the carbon nanotubes is completed to form a carbon nanotube film.

[0023] The method for manufacturing a carbon nanotube field effect transistor with rapid temperature control based on a thermoelectric device, in step (4), LOR3A and S-1813 double-layer photoresists are spin-coated on the surface of the carbon nanotube film in sequence by a coating machine, and the exposed pattern is a square area with a side length of 180-182 μm; the exposed sample is placed in an oxygen plasma cleaning machine with an oxygen flow rate of 180 sccm and a power of 200 W for 2 min to remove excess carbon nanotube film exposed outside the source and drain metal electrodes.

[0024] In the method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control, in step (5), a 30 nm hafnium oxide dielectric layer covering the carbon nanotube film is prepared at a temperature of 200°C using an atomic layer deposition device.

[0025] In the method for manufacturing a thermoelectric device-based fast temperature-controlled carbon nanotube field-effect transistor, in step (7), a reactive ion etcher is used for etching, and the etching conditions are: using carbon tetrafluoride with a flow rate of 50 sccm as the etching gas, a pressure of 5.0 to 5.5 Pa, a power of 100 W, and an etching time of 5 min 30 s.

[0026] The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control, in step (8), first spray acetone and then spray isopropyl alcohol on the surface of the thermoelectric device, let them stand for 1 minute and then wipe them with a dust-free cloth to remove surface impurities, and then adhere the phase change thermal conductive material to the surface of the thermoelectric device and to the substrate of the carbon nanotube field effect transistor; the surface temperature of the thermoelectric device is regulated by an external DC power supply, and the temperature range is -25°C to 120°C, the temperature change step is accurate to 0.1°C, and the temperature change rate reaches 3.84°C / s.

[0027] The design concept of the present invention is:

[0028] As the integration of electronic devices continues to increase and their size continues to shrink, their power density and operating temperature have increased significantly. At the same time, electronic devices will be widely used in more diverse environments in the future, and the impact of ambient temperature fluctuations on device performance cannot be ignored. In high-temperature environments such as space exploration, deep well drilling, and car driving, the high temperature generated when the equipment is running can easily cause thermal excitation effects, thereby reducing device performance. At the same time, low temperatures in application fields such as deep-sea exploration and resource exploration can lead to a decrease in the working performance of electronic components. Carbon nanotubes, with their excellent conductivity and electronic properties, have shown broad application prospects in antennas, nanowires, battery electrodes, and microsensors. In particular, carbon nanotube field-effect transistors (CNTFETs) have become a very promising candidate in the electronics field with their high speed, low power consumption, excellent thermal stability, and high reliability. In order to further improve the stability of CNTFETs, broaden their application scenarios, and optimize energy efficiency, it is particularly urgent to study the mechanism by which their performance is affected by temperature. Therefore, it is crucial to propose a solution that can accurately control the temperature of CNTFETs without noise interference.

[0029] Traditional temperature control platforms, such as those based on the Joule-Thomson effect and the Stirling effect, have demonstrated their functions and effectiveness in multiple application fields, but are limited by many moving parts, high noise, slow temperature control rates, and other issues, making it difficult to achieve optimal performance in the field of transistor temperature control. In contrast, thermoelectric temperature control technology based on the Peltier effect can convert electrical energy into thermal energy, and can achieve continuous and high-precision temperature control simply by adjusting the external working voltage and current. Compared with traditional temperature control platforms, thermoelectric temperature control technology exhibits significant advantages such as fast response speed, simple structure, no noise disturbance, and low maintenance. In particular, its tiny structural characteristics and noise-free operation provide a more efficient, stable and accurate temperature control solution for the temperature control of electronic devices, making thermoelectric technology show great potential in optimizing the integration and performance of electronic devices.

[0030] The present invention prepares a single-walled carbon nanotube channel by using a solution deposition method heated by a water bath, and manufactures CNTFET by combining techniques such as photolithography, gold evaporation, and atomic layer deposition. In order to improve the efficiency of temperature transfer and ensure that the heat transfer between CNTFET and thermoelectric devices is more stable, we added a phase change thermal conductive material between them so that the two fit closely and perform efficient heat exchange. By connecting a DC power supply (maximum voltage of 6.5 V and current of 0.45 A), the temperature of the thermoelectric device can be quickly changed, and a wide range of temperature control from -25°C to 120°C can be achieved under low power consumption conditions, thereby controlling the operating temperature of the CNTFET.

[0031] The present invention regulates and tests the electrical properties of carbon nanotube field effect transistors at different temperatures, and flexibly adjusts its polarity, so that the carbon nanotube field effect transistor exhibits N-type characteristics at high temperature and transforms into bipolar characteristics at low temperature. Temperature changes are achieved through thermoelectric devices, and the electrical performance of CNTFETs is tested at multiple temperature points in an air environment. This feature enables CNTFETs to achieve reversible polarity changes from N-type to bipolar in different temperature ranges. During the test, we fully characterized key electrical parameters including transfer characteristic curves, threshold voltage, subthreshold swing, current switching ratio, transconductance, etc., and gained an in-depth understanding of the changes in the electrical behavior of CNTFETs during the entire temperature control process.

[0032] The advantages and beneficial effects of the present invention are:

[0033] 1. The carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices and its manufacturing method involved in the present invention realizes the compatible integration of transistors and thermoelectric devices by utilizing the characteristics of thermoelectric devices such as small size, no noise disturbance, no moving parts and fast temperature control speed. The temperature of the transistor is controlled by the thermoelectric device, and the reversible polarity change of the carbon nanotube field effect transistor is realized in an efficient, convenient, rapid and controllable manner, and the electrical performance parameters in each temperature range are obtained, thereby ensuring the stability of the device testing process, and providing a new method for performance control of carbon nanotube field effect transistors.

[0034] 2. The carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices and its manufacturing method involved in the present invention utilizes a method of heating a carbon nanotube solution in a water bath to deposit and prepare a carbon nanotube channel. The preparation process is simple, effective, clean and lossless, ensuring the uniformity of device performance.

[0035] 3. The carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices and its manufacturing method involved in the present invention, through the precise and disturbance-free rapid temperature control of thermoelectric devices, studied the changes in the electrical performance of CNTFET in various temperature ranges, successfully observed the temperature-induced reversible polarity change phenomenon, and accurately measured the key electrical parameters under various temperature conditions, including threshold voltage, subthreshold swing, current switching ratio and transconductance, etc. It is particularly pointed out that CNTFET exhibits bipolar characteristics below 20°C, and turns into N-type characteristics above 70°C, and with the increase of temperature, the threshold voltage increases, the subthreshold swing increases, and the current switching ratio and transconductance both decrease.

[0036] The performance control method of carbon nanotube field effect transistor based on thermoelectric temperature control technology can not only effectively characterize the impact of ambient temperature changes on the performance of carbon nanotube field effect transistors, but also realize accurate and rapid control of device temperature, thereby improving the stability and reliability of specific device performance. Integrated thermoelectric temperature control technology effectively reduces the volume and noise disturbance of traditional temperature control systems, and reduces the cost and energy consumption of temperature control systems. It has expanded new ideas for the integration and application of thermoelectric devices, and at the same time provided a new method for the performance control of carbon nanotube field effect transistors, which is of great significance for the temperature control of transistors and related temperature response research. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The present invention relates to a carbon nanotube field effect transistor based on rapid temperature control of a thermoelectric device and a device structure schematic diagram of a carbon nanotube field effect transistor in a manufacturing method thereof.

[0038] Figure 2 This is an optical microscope photograph of a carbon nanotube field-effect transistor prepared by micro-nano processing.

[0039] Figure 3 This is a picture of a thermoelectric device based on thermoelectric effect according to the present invention (a), and a schematic diagram of temperature transfer of a basic thermoelectric unit based on thermoelectric effect (b).

[0040] Figure 4 The present invention is a structural diagram of a thermoelectric device integrated into a field effect transistor.

[0041] Figure 5 The figure is a physical picture of the thermoelectric device integrated into the carbon nanotube field effect transistor according to the present invention. Among them, (a) is a side view, and the inset is a local enlarged view; (b) is a top view, and (c) is a detail drawing.

[0042] Figure 6In the study of carbon nanotube field effect transistors based on rapid temperature control of thermoelectric devices, the transfer characteristic curve of the transistor during the temperature control process from 120 ℃ to - 25 ℃ is shown under the rapid and precise temperature control of thermoelectric devices. Among them, the arrows in (a) represent the changing trend of the transfer characteristic curve of the carbon nanotube field effect transistor from 120 ℃ to -25 ℃; (b) The figure clearly shows the transfer characteristic curves corresponding to the three special temperature nodes of the transistor under the temperature control of the thermoelectric device. The three special temperature nodes are 120 ℃, 10 ℃, and - 25 ℃ respectively; the vertical axis Current represents the current at both ends of the source and drain of the transistor I (A), the horizontal axis Voltage represents the gate voltage at both ends of the source and drain electrodes V (V).

[0043] Figure 7 The electrical characteristic curve of the on-state and off-state current of the carbon nanotube field effect transistor under the temperature control of the thermoelectric device changes with temperature. In the figure, the vertical axis Current represents the current at both ends of the source and drain of the transistor. I (A), the horizontal axis Temperature represents the temperature state (℃) of the transistor when it is tested under the temperature control of the thermoelectric device.

[0044] Figure 8 This is a graph showing the temperature variation of the transistor current switching ratio of the carbon nanotube field effect transistor under the temperature control of the thermoelectric device. I on / I off It represents the ratio of the transistor's on-state current to its off-state current, and the horizontal axis Temperature represents the temperature state of the transistor (°C).

[0045] Fig. 9 The curve of the transistor transconductance of the carbon nanotube field effect transistor under the temperature control of the thermoelectric device is as follows. g m represents the transconductance of the transistor (A / V), and the horizontal axis Temperature represents the temperature state of the transistor during testing (℃).

[0046] Fig.10 The curve of the subthreshold swing of the carbon nanotube field effect transistor under the temperature control of the thermoelectric device varies with temperature. SS represents the subthreshold swing of the transistor (mV / dec), and the horizontal axis Temperature represents the temperature state of the transistor (℃).

[0047] Fig.11The curve of the threshold voltage of the carbon nanotube field effect transistor under the temperature control of the thermoelectric device varies with temperature. V th represents the threshold voltage of the transistor (V), and the horizontal axis Temperature represents the temperature state of the transistor (℃). DETAILED DESCRIPTION

[0048] In the specific implementation process, the present invention proposes for the first time a performance control method for carbon nanotube field effect transistors based on thermoelectric temperature control technology. A carbon nanotube field effect transistor is prepared under room temperature conditions. In order to ensure the immediacy and accuracy of temperature control, the back of the silicon substrate of the carbon nanotube field effect transistor is bonded to the thermoelectric device through a phase change thermal conductive material (PCM). The electrical performance of the carbon nanotube field effect transistor under temperature change is controlled by the rapid temperature change function of the thermoelectric device. The electrical performance changes of CNTFET in various temperature ranges are systematically studied, and reversible polarity changes in different temperature ranges are observed. The transfer characteristic curve, threshold voltage, subthreshold swing, current switching ratio, transconductance and other electrical performance parameters of CNTFET under different temperature conditions are obtained. The performance control method for carbon nanotube field effect transistors based on thermoelectric temperature control technology can not only effectively characterize the impact of ambient temperature changes on the performance of carbon nanotube field effect transistors, but also realize precise control of device temperature, thereby improving the stability and reliability of specific device performance. Integrated thermoelectric temperature control technology effectively reduces the volume and noise disturbance of traditional temperature control systems, reduces the cost and energy consumption of temperature control systems, expands new ideas for the integration and application of thermoelectric devices, and provides a new method for performance regulation and testing of carbon nanotube field effect transistors.

[0049] The present invention is further described in detail below through examples and drawings. Example

[0050] In this embodiment, the carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices and the manufacturing method thereof are as follows:

[0051] like Figure 1 As shown, the basic process of making a carbon nanotube field effect transistor for temperature control of a thermoelectric device is as follows:

[0052] The initial substrate is a heavily doped P-type silicon substrate (doping boron concentration is 10 19 ~10 21 atoms / cm 3 ), the resistivity is 0.05~0.2 Ω·cm.

[0053] In the first step, the substrate was cleaned by ultrasonic cleaning with acetone and isopropanol at a frequency of 40 Hz and a power of 100 W, and each cleaning was performed twice, each for 5 min. The oxygen plasma (O-plasma) cleaning time was 10 min, the oxygen flow rate was 180 sccm, and the power was 200 W.

[0054] The second step is to make source / drain metal electrodes to the target substrate. Vacuum electron beam evaporation technology is used to make a photoresist mask layer through photolithography technology. The maximum effective range of the film is 2 cm × 2 cm exposure area. The required electrode deposition area is exposed to evaporate titanium / gold electrodes at the source and drain.

[0055] The third step is to deposit a single-walled carbon nanotube channel. The single-walled carbon nanotubes are selected from high-quality arc discharge carbon nanotubes from Carbon Solution Inc., with a concentrated diameter distribution, a peak diameter of 1.55±0.1 nm, and a bundle length of 1~5 μm. First, the bulk carbon nanotubes and toluene are mixed in a mass ratio of 1:8, and the carbon nanotube bundles and insoluble substances are removed by ultrasonic dispersion (30 min) and centrifugal purification (45000g, 1 h) to obtain a semiconductor single-walled carbon nanotube solution with a purity higher than 99.9 wt%, and the supernatant is collected as the channel material. The carbon nanotube solution is then ultrasonically treated with an ultrasonic frequency of 40 Hz and a power of 100 W. The carbon nanotube solution dispersed by ultrasonic vibration is transferred to a culture dish.

[0056] During the deposition of the carbon nanotube film, the cleaned silicon substrate was first heated to 180°C on a hot plate and baked for 30 minutes to remove moisture from the substrate. In order to make the single-walled carbon nanotubes better adsorbed on the substrate and evenly dispersed, the precursor primer (MCC-Primer, Micro Chem Corporation Primer of Microchem Company, USA) was spin-coated on the surface of the substrate by a gel-spinning machine, and then baked on a hot plate at 105°C for 2 minutes. The baked substrate was immersed in a culture dish of the carbon nanotube solution dispersed by ultrasonic vibration, and the culture dish was placed in a water bath at 60°C. The liquid level of deionized water in the water bath just exceeded the liquid level of the carbon nanotube solution in the culture dish. After two and a half hours, the deposition of single-walled carbon nanotubes was completed to form a carbon nanotube film.

[0057] In the fourth step, LOR3A and S-1813 double-layer photoresists were spin-coated on the surface of the carbon nanotube film in sequence, and the exposed pattern was a square area with a side length of 180-182 μm. The exposed sample was placed in an oxygen plasma cleaner (O-plasma) at a pressure of 3.0 Pa, an oxygen flow rate of 180 sccm, a power of 200 W, and a cleaning time of 2 min to accurately remove the excess carbon nanotube film exposed in the non-patterned area outside the source and drain metal electrodes.

[0058] In the fifth step, a 30 nm hafnium oxide dielectric layer covering the carbon nanotubes is prepared at a temperature of 200 °C using an atomic layer deposition device.

[0059] The sixth step is to use photolithography technology to make a photoresist mask layer through reactive ion etching. The maximum effective range of the mask is 2 cm × 2 cm exposure area. The required hafnium oxide etching area is exposed to expose the titanium / gold source and drain metal electrodes in contact with the carbon nanotube channel and the substrate. The patterned hafnium oxide is etched with carbon tetrafluoride so that the source and drain electrodes are exposed to the air to obtain a carbon nanotube field effect transistor array. Among them, the etching conditions are: using a reactive ion etcher (RIE) for etching, using carbon tetrafluoride with a flow rate of 50 sccm as the etching gas, the pressure is 5.0~5.5 Pa, the power is 100W, and the etching time is 5 min30 s.

[0060] In the carbon nanotube field effect transistor, the substrate is composed of silicon dioxide / heavily doped silicon wafer / silicon dioxide from bottom to top, the source and drain electrodes and the gate electrode are composed of a stacked composite structure of titanium / gold from bottom to top, the channel is composed of a single-walled carbon nanotube deposited by a solution, and the dielectric layer material between the gate electrode and the channel is hafnium oxide. The overall structure is: silicon dioxide / silicon / silicon dioxide / titanium / gold / semiconductor carbon nanotubes / hafnium oxide / titanium / gold, a stacked composite structure from bottom to top. The thickness is: 300 nm / 300 μm / 300 nm / 5 nm / 50 nm / 3~6 nm / 30 nm / 5 nm / 50 nm, and the growth temperature of the hafnium oxide dielectric layer is 200 ℃.

[0061] The above is the production process of carbon nanotube field effect transistor, which constitutes the following Figure 1 The device structure shown in the figure has a bottom substrate composed of silicon dioxide (SiO2) / P-type doped silicon (Si) / silicon dioxide (SiO2) from bottom to top. First, titanium (Ti) / gold (Au) electrodes as source and drain are evaporated on the silicon substrate using electron beam evaporation technology. The carbon nanotube (CNT) in contact with the electrode and the silicon substrate serves as the device channel. Hafnium oxide (HfO2) is grown on the carbon nanotube channel as a dielectric layer, and titanium (Ti) / gold (Au) electrodes are evaporated on the dielectric layer as the gate electrode of the device.

[0062] like Figure 2As shown in the figure, an optical microscope photo of a carbon nanotube field effect transistor prepared by micro-nano processing, a single field effect transistor consists of a set of source / drain / gate electrodes (Source / Drain / Gate) and a hafnium oxide dielectric layer (HfO2) and a carbon nanotube channel covered by the dielectric layer. The electrode area of ​​the tested carbon nanotube field effect transistor is 500 μm × 200 μm, the channel width is 40 μm, the gate control area of ​​the top gate electrode for the channel is 500 μm × 40 μm, the gate electrode area is 100 μm × 100 μm, and the thickness of the middle hafnium oxide dielectric layer is 30 nm. The carbon nanotube channel used is prepared by solution deposition by heating in a water bath. The specific process flow is as follows: Figure 1 As shown in the embodiment.

[0063] In the specific experiment, it is necessary to determine the specific manufacturing process of the carbon nanotube field effect transistor and the specific temperature control scheme of the carbon nanotube field effect transistor integrated into the thermoelectric device. In this embodiment, the study of the rapid temperature change characteristics of the carbon nanotube field effect transistor based on the temperature control of the thermoelectric device and its manufacturing method include the following steps: (1) to (7) are the specific manufacturing process flow of the carbon nanotube field effect transistor. (8) is the details of the specific temperature control scheme of the carbon nanotube field effect transistor integrated into the thermoelectric device.

[0064] (1) Using heavily doped P-type silicon substrates, ultrasonic cleaning technology was used to remove surface impurities by ultrasonic cleaning with acetone and isopropanol in turn. The ultrasonic cleaning frequency was 40 Hz and the power was 100 W. The cleaning was repeated twice, each time for 5 min. Afterwards, an oxygen plasma cleaner was used to remove surface oxides, water molecules, and other residual impurities to ensure the cleanliness of the substrate surface. The oxygen plasma (O-plasma) cleaning time was 10 min, the oxygen flow rate was 180 sccm, and the power was 200 W.

[0065] (2) When preparing electrodes, vacuum electron beam evaporation technology is used. The photoresist mask layer is made by photolithography technology. The maximum effective range of the film is 2 cm × 2 cm exposure area. The required electrode evaporation area is exposed to obtain titanium / gold electrodes for source / drain. The thickness of the metal electrode Ti layer ranges from 5 to 6 nm, and the thickness of the Au layer ranges from 50 to 51 nm.

[0066] (3) In this embodiment, the carbon nanotube channel is deposited by a solution deposition method heated in a water bath. First, the cleaned silicon substrate is heated to 180°C on a hot plate and baked for 30 minutes to remove moisture from the substrate. In order to make the single-walled carbon nanotubes better adsorbed on the substrate and evenly dispersed, the Primer primer is spin-coated on the upper surface of the substrate by a glue spreader, and then baked on a hot plate at 105°C for 2 minutes. The baked substrate is immersed in a 1:8 toluene carbon nanotube solution dispersed by ultrasonic oscillation at 40 Hz and a power of 100 W, and the culture dish is placed in a 60°C water bath for heating and deposition for two and a half hours. The liquid level of deionized water in the water bath just exceeds the liquid level of the toluene carbon nanotube solution in the culture dish. After two and a half hours, the deposition of the single-walled carbon nanotube is completed;

[0067] (4) In this embodiment, oxygen plasma etching technology is used to clean the excess carbon nanotube film exposed outside the source and drain metal electrodes by introducing oxygen. LOR3A and S-1813 double-layer photoresists are sequentially spin-coated on the surface of the carbon nanotube film. The exposed pattern is a square area with a side length of 180~182 μm. The exposed sample is placed in an oxygen plasma cleaning machine (O-plasma) with an oxygen flow rate of 180 sccm and a power of 200 W for 2 min to remove the excess carbon nanotube film exposed outside the source and drain metal electrodes. Then, the excess photoresist is removed by Remover 90 ℃ 20 min + IPA 90 ℃ 2 min;

[0068] (5) In this embodiment, the prepared hafnium precursor, amino ligand and water are used to prepare a 30 nm hafnium oxide dielectric layer covering the carbon nanotubes at a temperature of 200°C by an atomic layer deposition device;

[0069] (6) A titanium / gold top metal gate electrode in contact with the hafnium oxide dielectric layer was prepared by vacuum electron beam evaporation technology. The obtained titanium / gold electrode had a metal electrode Ti layer thickness ranging from 5 to 6 nm and an Au layer thickness ranging from 50 to 51 nm.

[0070] (7) In this embodiment, a photoresist mask layer is formed on the surface of the hafnium oxide dielectric layer by reactive ion etching using photolithography technology. The maximum effective range of the film is an exposure area of ​​2 cm × 2 cm. The desired hafnium oxide etching area is exposed to expose the titanium / gold source and drain metal electrode area in contact with the carbon nanotube channel and the substrate. The etching conditions are: using carbon tetrafluoride with a flow rate of 50 sccm as the etching gas, a pressure of 5.0~5.5 Pa, a power of 100 W, and an etching time of 5 min 30 s. The patterned hafnium oxide is etched so that the source and drain electrodes are exposed to the air to obtain a carbon nanotube field effect transistor array.

[0071] (8) In this embodiment, a carbon nanotube field effect transistor based on rapid temperature control of a thermoelectric device and a method for making the same are described. Acetone and isopropyl alcohol are sprayed on the surface of the thermoelectric device to remove surface impurities, a phase change thermal conductive material (PCM, Honeywell PTM7950) is bonded to the surface of the thermoelectric device, and then the silicon substrate of the transistor is bonded to the surface of the phase change thermal conductive material. The surface temperature of the thermoelectric device is regulated by an external DC power supply (maximum voltage 6.5 V, current 0.45 A) to study the temperature variation characteristics of the transistor, the temperature range of which is -25 ℃ ~ 120 ℃, and the temperature of the surface of the thermoelectric device is characterized by an ultra-fine T-type thermocouple thermometer with a wire diameter of 0.05 mm. Thus, rapid regulation of the temperature range of -25 ℃ to 120 ℃ is achieved, and the temperature variation rate is as high as 3.84 ℃ / s, and the electrical characteristics of the carbon nanotube field effect transistor at different temperatures are studied in depth.

[0072] like Figure 3 As shown in the figure, the thermoelectric device based on the thermoelectric effect and the basic unit structure diagram. The top and bottom surfaces of the thermoelectric device are both metal thermal conductive substrates (Metal wire). The metal thermal conductive substrate is a copper thermal conductive substrate plated with nickel and gold layers on the surface of the copper thermal conductive substrate, and the middle is composed of multiple basic units composed of N-type and P-type semiconductors. Among them, the basic element of the thermoelectric device is composed of a metal thermal conductive substrate connecting two thermoelectric legs, and the thermoelectric legs are made of P-type semiconductor (P) and N-type semiconductor (N) materials respectively. After a DC voltage is applied to both ends of the thermoelectric device, the external electric field forces the carriers to move in a certain direction in the loop. The carriers in the metal thermal conductive substrate and the N-type semiconductor are electrons, and the carriers in the P-type semiconductor are holes. The energy of electrons in the metal thermal conductive substrate is lower than that in its N-type semiconductor. When electrons flow from the metal thermal conductive substrate into the N-type thermoelectric leg, they need to absorb heat, so that the heat absorption effect (Heat absorbed) can be observed at the interface of the cooled surface (Cooled surface); when electrons flow from the N-type thermoelectric leg into the metal thermal conductive substrate, the electrons flow from the high energy level into the low energy level to release heat, and the heat dissipation effect (Heat dissipation) can be observed at such a node; the holes in the P-type thermoelectric leg move in the opposite direction of the electrons, so the electrons from the metal thermal conductive substrate meet at a node of the P-type thermoelectric leg and recombine, releasing energy, and the node produces a heat dissipation effect. The heat at the node is dissipated to the outside through the heat sink (Heat sink); at another node, the electrons and holes are separated under the action of the electric field, and energy needs to be absorbed, resulting in a heat absorption effect. Therefore, it can be observed that one side of the device becomes cold and the other side becomes hot, and then the temperature can be controlled by an external DC power supply to produce a cooling or heating effect. By applying an external voltage, a temperature difference can be generated on the upper and lower surfaces of the thermoelectric device, achieving a rapid temperature control effect. The dimensions of the thermoelectric device are: 0.3 cm high, 1.2 cm long, and 1.2 cm wide.

[0073] like Figure 4 As shown in the figure, the structure of the carbon nanotube field effect transistor integrated into the thermoelectric device. Phase change thermal conductive material (PCM) is attached between the thermoelectric device (TEdevice) and the silicon substrate of the transistor. The thermoelectric device is located at the bottom, and its upper surface is the PCM phase change thermal conductive material. Figure 1 The carbon nanotube field effect transistor shown. The thermoelectric device (TEdevice) and the silicon substrate of the carbon nanotube field effect transistor are closely attached through the phase change thermal conductive material (PCM), which increases the temperature control efficiency of the thermoelectric device for the transistor. The main purpose of this design is to improve the efficiency of heat transfer between the thermoelectric device and the field effect transistor. By using PCM, the thermal resistance increased by the air gap caused by the direct attachment of the substrate and the thermoelectric device can be effectively reduced. This not only increases the heat transfer efficiency between the transistor and the thermoelectric device, but also enhances the efficiency and stability of the thermoelectric device in real-time temperature control of the field effect transistor.

[0074] like Figure 5 As shown, the physical picture of the carbon nanotube field effect transistor integrated into the thermoelectric device for temperature-varying characteristic testing. As can be seen from the (a) side view, the physical picture of the carbon nanotube field effect transistor integrated with the thermoelectric device consists of a thermoelectric device (TE device) / phase change thermal conductive material (PCM) / carbon nanotube field effect transistor (CNTFET) and a thermocouple (Thermocouple) used for temperature measurement from top to bottom. Two conductors (Conductor) are connected to the positive and negative electrodes of the thermoelectric device respectively. The upper right is the (b) top view of the whole object, and the lower right picture is the (c) detail drawing after the top view is enlarged. The phase change thermal conductive material between the carbon nanotube field effect transistor and the thermoelectric device can be seen in the enlarged detail drawing. Among them, the size of the thermoelectric device is: 1.2 cm × 1.2 cm × 0.3 cm. The size of the phase change thermal conductive material after cutting is 1.1 cm × 0.9 cm × 0.1 cm. 576 carbon nanotube field effect transistors are made on the substrate with the size of 1.1 cm × 0.9 cm × 0.1 cm. The specific method is referenced Figure 1 and Figure 2 Details of the implementation.

[0075] like Figure 6As shown, a carbon nanotube film was prepared according to the experimental process and the electrical performance was tested at various temperatures by using thermoelectric devices to achieve rapid and accurate temperature control. When the source-drain voltage is -1 V, the transfer characteristic curve of the carbon nanotube field effect transistor with rapid temperature control by thermoelectric devices, the gate voltage is -5 V~+5 V. It can be clearly seen from the transfer characteristic curves of the transistor at 120 ℃ and -25 ℃ that the polarity of the transistor changes from an N-type transistor at high temperature to a bipolar transistor at low temperature in different temperature ranges. The dotted line is the transfer characteristic curve of the carbon nanotube field effect transistor at 120 ℃, and the solid line is the transfer characteristic curve at -25 ℃. The direction of the arrow represents the change process of the transfer characteristic curve from high temperature to low temperature. Figure 6 (a) It can be seen that with the stable temperature control of the thermoelectric device, the polarity of the carbon nanotube-transistor at 120 ℃ is N-type. As the temperature gradually decreases, when the temperature reaches -25 ℃, the polarity of the carbon nanotube-transistor changes to bipolar. Figure 6 (b) It can be seen that in the temperature range of 120 ℃ ~ 10 ℃, the transfer characteristic curve is shifted to the right as a whole, and the transfer characteristic curve of the transistor is N-type; in the temperature range of 10 ℃ ~ - 25 ℃, the transfer characteristic curve is shifted to the left as a whole, and the transfer characteristic curve of the transistor is bipolar. The temperature control method of the present invention measures the transfer characteristic curve at each temperature multiple times during the test process, and the transfer characteristic curves at the same temperature are basically consistent, reflecting the stability of the temperature control of the thermoelectric device.

[0076] like Figure 7 As shown, the electrical performance of the carbon nanotube field effect transistor is characterized by the on-state current-off-state current changing with temperature. Figure 7 It can be seen that the dotted line graph is the curve of the on-state current of the carbon nanotube field effect transistor changing with temperature. At 120 ℃, the on-state current of the transistor is 5.82 × 10 5 As the temperature decreases, the on-state current gradually decreases to 3.31387 × 10 5 A; The dotted line diagram is the curve of the off-state current of the carbon nanotube field effect transistor changing with temperature. At 120 ℃, the on-state current of the transistor is 1.65715 × 10 8 As the temperature decreases, the on-state current gradually decreases to 2.9781 × 10 10 A. By Figure 7It can be seen that in the cooling process from 120 ℃ to -25 ℃, the on / off current of the transistor at various temperatures was tested in steps of 10 ℃ through precise temperature control of the thermoelectric device, which reflects the effectiveness of the temperature control test of the thermoelectric device. As the temperature decreases, the overall trend of the on-state current of the carbon nanotube field effect transistor remains unchanged from 120 ℃ to 10 ℃, and the on-state current decreases in the temperature change process from 10 ℃ to - 25 ℃; as the temperature decreases, the off-state current of the transistor changes more greatly, and the off-state current of the carbon nanotube field effect transistor gradually decreases from 120 ℃ to - 25 ℃. Compared with the change of the on-state current at the same order of magnitude, the off-state current is reduced by about two orders of magnitude overall.

[0077] like Figure 8 As shown, the electrical performance characterization of the current switching ratio of the carbon nanotube field effect transistor changes with temperature, corresponding to Figure 7 The ratio of the on-state current to the off-state current. The on-off ratio is defined as the ratio of the current in the device when it is turned on (i.e., the "on" state) to the current in the device when it is turned off (i.e., the "off" state). The current on-off ratio reflects the current control capability of the field effect transistor in different states. A high on-off ratio means that the device can carry a larger current when it is turned on, and has a lower leakage current when it is turned off, thus having better stability and anti-interference ability. Figure 8 It can be seen that as the temperature decreases, the current switch ratio of the transistor gradually increases, from 3511.47 at 120 ℃ to 75344.67 at - 25 ℃ in the temperature change process from 120 ℃ to - 25 ℃. Under the temperature difference of 145 ℃, the switch ratio of the transistor increases by 21.5 times. In the temperature change process from 10 ℃ to - 25 ℃, the rising trend slows down. The results show that with the temperature regulation of the thermoelectric device, the current control ability of the carbon nanotube field effect transistor under different temperature conditions gradually changes, and the current regulation ability at low temperature increases significantly, which reflects the feasibility and effectiveness of thermoelectric devices for transistor temperature control.

[0078] like Fig. 9 As shown in the figure, the dotted line graph of the transconductance of the carbon nanotube field effect transistor changes with temperature. The transconductance is used to describe the control ability of the gate voltage on the drain current. The larger the transconductance, the stronger the control ability of the gate voltage on the drain current, that is, the stronger the amplification effect of the transistor. Fig. 9It can be seen that the transconductance of the transistor is 3.648 A / V at 120 ℃. As the temperature decreases, the transconductance of the transistor is 4.596 A / V at 60 ℃, and the transconductance increases to 15.884 A / V at -25 ℃. The decrease in temperature causes the transconductance of the transistor to gradually increase. The results show that as the thermoelectric device changes the temperature control of the transistor, the control ability of the gate voltage on the drain current in the carbon nanotube field effect transistor has a significant effect. As the temperature decreases, the control ability of the gate voltage on the drain current gradually increases.

[0079] like Fig.10 As shown in the figure, the subthreshold swing of the carbon nanotube field effect transistor changes with temperature. The subthreshold swing describes the change in gate voltage required for the source-drain current of the transistor to change tenfold in the subthreshold region. It is a measure of the slope of the gate-controlled source-drain current curve and measures the rate at which the transistor switches between the on and off states in the subthreshold region. Fig.10 It can be seen that when the device temperature is 120 ℃, the subthreshold swing of the carbon nanotube field effect transistor is 272.103 mV / dec. As the temperature decreases, the subthreshold swing of the device gradually decreases. When it reaches -25℃, the subthreshold swing of the transistor is 143.667 mV / dec. The results show that as the temperature of the thermoelectric device is regulated, the subthreshold swing of the transistor gradually decreases, that is, the temperature affects the conversion rate between the on and off states of the transistor in the subthreshold region. As the temperature decreases, the conversion rate between the on and off states of the carbon nanotube field effect transistor in the subthreshold region gradually decreases.

[0080] like Fig.11 As shown in Figure 2, the threshold voltage of a carbon nanotube field effect transistor changes with temperature. The threshold voltage is the minimum gate-source voltage required to turn the transistor from the off state to the on state. V GS ),when V GS When the threshold voltage is exceeded, the transistor begins to conduct. Fig.11It can be seen that in the temperature range of 120 ℃ ~ 10 ℃, as the temperature decreases, the threshold voltage of the transistor gradually decreases, from 3.599 V at 120 ℃ to 0.302 V at 10 ℃. However, in the temperature range of 10 ℃ ~ - 25 ℃, as the temperature decreases, the threshold voltage of the transistor gradually increases, from 0.302 V at 10 ℃ to 0.751 V at -25 ℃. The results show that with the temperature regulation of the thermoelectric device, the threshold voltage amplitude of the transistor changes, and the temperature significantly affects the minimum gate-source voltage required for the transistor to change from the off state to the on state. With the change of temperature, the minimum gate-source voltage required for the carbon nanotube field effect transistor to change from the off state to the on state changes continuously.

[0081] Through the above method, the carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices proposed in the present invention is successfully realized.

[0082] The results of the embodiment show that a carbon nanotube field effect transistor based on rapid temperature control of thermoelectric devices and its manufacturing method, the electrical performance of the carbon nanotube field effect transistor under temperature change is regulated by the rapid temperature change function of the thermoelectric device without noise disturbance, and the changes in the electrical performance of the CNTFET in each temperature range are systematically studied. The reversible polarity transition in different temperature ranges is observed. The electrical performance parameter results of the CNTFET under different temperature conditions show that the transfer characteristic curve, threshold voltage, subthreshold swing, current switching ratio, transconductance and other electrical performance parameters of the CNTFET change to varying degrees with the change of temperature. This method can realize the stable regulation and measurement of the electrical performance of the carbon nanotube field effect transistor under temperature control, and has a high practical application value. The method involved in the present invention is simple and effective, compatible with mainstream semiconductor processes, and expands new ideas for the integration and application of thermoelectric devices, while providing a new method for the performance regulation of carbon nanotube field effect transistors.

Claims

1. A fast temperature-controlled carbon nanotube field effect transistor based on thermoelectric devices, characterized in that: The carbon nanotube field effect transistor comprises a substrate, a titanium / gold source-drain electrode in contact with a channel, a hafnium oxide dielectric layer, and a stacked titanium / gold gate electrode located on the hafnium oxide dielectric layer. The overall structure is: silicon dioxide / heavily doped P-type silicon wafer / silicon dioxide / titanium / gold / semiconductor carbon nanotube / hafnium oxide / titanium / gold, a bottom-up stacked composite structure, the substrate is a bottom-up silicon dioxide / heavily doped P-type silicon wafer / silicon dioxide combined structure, the channel is a single-walled carbon nanotube channel deposited by water bath heating, the gate region is located above the channel, and the gate region is sequentially structured from bottom to top as a hafnium oxide dielectric layer and a gate electrode; A thermoelectric device is mounted under the substrate of the carbon nanotube field effect transistor through a phase change thermal conductive material, so that the thermoelectric device and the carbon nanotube field effect transistor are connected through the phase change thermal conductive material; the thermoelectric device is connected to an external DC power supply, and the temperature of the carbon nanotube field effect transistor is regulated based on the Peltier effect; the thermoelectric device includes a metal thermal conductive substrate on the top and bottom, and an N-type and P-type semiconductor array in the middle of the metal thermal conductive substrate. The basic element of the thermoelectric device is composed of a metal thermal conductive substrate connecting two thermoelectric legs, and the thermoelectric leg materials are respectively made of P-type semiconductor and N-type semiconductor.

2. A method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 1, characterized in that: The steps include: (1) The substrate is ultrasonically cleaned with acetone and isopropanol to remove surface impurities, and then oxygen plasma cleaning is used to further remove surface residues to ensure that the substrate is clean; (2) Using photolithography technology, a photoresist mask layer is formed on the substrate. The maximum effective range of the mask layer is an exposure area of ​​2 cm × 2 cm. The required source and drain electrode deposition areas are exposed on the substrate. Titanium / gold stacked metal electrodes are prepared in the specified areas by vacuum electron beam evaporation technology to construct the source and drain electrodes of the transistor. (3) After the Primer photoresist is evenly spin-coated on the substrate, it is immersed in the carbon nanotube solution after ultrasonic dispersion treatment, and the carbon nanotubes are deposited on the substrate by water bath heating to form a transistor channel layer; (4) Using oxygen plasma cleaning technology and photolithography technology, first, using photolithography technology, a photoresist mask layer is constructed on the substrate where the carbon nanotube channel has been deposited; then, using oxygen plasma cleaning technology, the portion other than the source and drain metal electrodes is processed to remove excess carbon nanotube film; (5) Using atomic layer deposition technology, a hafnium oxide dielectric layer is evenly covered on the carbon nanotube channel to provide an insulating foundation for subsequent gate electrode fabrication; (6) using photolithography technology to expose the required gate electrode evaporation area on the hafnium oxide dielectric layer, and using vacuum electron beam evaporation technology to prepare a titanium / gold gate electrode in close contact with the hafnium oxide dielectric layer; (7) Using photolithography technology to prepare a photoresist mask layer, exposing the required hafnium oxide etching area to expose the titanium / gold source and drain metal electrodes in contact with the carbon nanotube channel and the substrate, and using reactive ion etching technology with carbon tetrafluoride as the reaction gas to etch the hafnium oxide, and finally obtaining a carbon nanotube field effect transistor array with a complete structure; (8) Construct a thermoelectric device compatible with carbon nanotube field effect transistors. Spray acetone and isopropyl alcohol on the surface of the thermoelectric device to remove surface impurities. Then, adhere a phase change thermal conductive material to the surface of the thermoelectric device and tightly adhere the substrate of the transistor to the surface of the phase change thermal conductive material. By applying an external DC power supply, the surface temperature of the thermoelectric device can be controlled, thereby flexibly adjusting the operating temperature of the transistor.

3. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (1), the ultrasonic cleaning frequency of acetone and isopropanol used is 40 Hz, the power is 100 W, and the cleaning is performed twice for five minutes each; the oxygen plasma cleaning time is 10 min, the flow rate of oxygen is 180 sccm, and the power is 200 W.

4. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (2) and step (6), an electron beam evaporator is used to evaporate the top gate electrode and the source and drain electrodes at both ends. The thickness of the Ti layer ranges from 5 to 6 nm, and the thickness of the Au layer ranges from 50 to 51 nm.

5. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (3), carbon nanotubes and toluene are mixed in proportion, and carbon nanotube bundles and insoluble substances are removed by ultrasonic dispersion and centrifugal purification to obtain a semiconductor carbon nanotube solution. The supernatant is collected as a channel material, and the carbon nanotube solution is ultrasonically treated at an ultrasonic frequency of 40 Hz and a power of 100 W. The carbon nanotube solution after ultrasonic oscillation dispersion is transferred to a culture dish; During the deposition process of the carbon nanotube film, the cleaned silicon substrate is first heated to 180°C on a hot plate and baked for 30 minutes to remove moisture from the substrate. In order to make the carbon nanotubes better adsorbed on the substrate and evenly dispersed, the Primer primer is spin-coated on the surface of the substrate by a coater, and then baked on a hot plate at 105°C for 2 minutes; the baked substrate is immersed in a culture dish of the carbon nanotube solution dispersed by ultrasonic vibration, and the culture dish is placed in a 60°C water bath. The liquid level of deionized water in the water bath just exceeds the liquid level of the carbon nanotube solution in the culture dish. After two and a half hours, the deposition of carbon nanotubes is completed to form a carbon nanotube film.

6. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (4), a double layer of photoresist LOR3A and S-1813 is sequentially spin-coated on the surface of the carbon nanotube film by a coating machine, and the exposed pattern is a square area with a side length of 180-182 μm; The exposed sample was placed in an oxygen plasma cleaning machine with an oxygen flow rate of 180 sccm and a power of 200 W for 2 min to remove excess carbon nanotube film exposed outside the source and drain metal electrodes.

7. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (5), a 30 nm hafnium oxide dielectric layer covering the carbon nanotube film is prepared at a temperature of 200°C using an atomic layer deposition device.

8. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (7), a reactive ion etcher is used for etching, and the etching conditions are: using carbon tetrafluoride as the etching gas with a flow rate of 50 sccm, a pressure of 5.0 ~ 5.5 Pa, a power of 100 W, and an etching time of 5 min 30 s.

9. The method for manufacturing a carbon nanotube field effect transistor based on a thermoelectric device with rapid temperature control according to claim 2, characterized in that: In step (8), the surface of the thermoelectric device is first sprayed with acetone and then with isopropanol, and then left to stand for 1 min and wiped with a dust-free cloth to remove surface impurities. The phase change thermal conductive material is bonded to the surface of the thermoelectric device and bonded to the substrate of the carbon nanotube field effect transistor. The surface temperature of the thermoelectric device is regulated by an external DC power supply, and the temperature range is -25°C to 120°C. The temperature change step is accurate to 0.1°C and the temperature change rate reaches 3.84°C / s.

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