Field effect transistor and preparation method thereof

Abstract

The present invention provides a field-effect transistor and a method for preparing the same. The method for preparing the field-effect transistor comprises: S10: mixing raw materials including polymethyl methacrylate and polystyrene to prepare a polymer solution; S20: contacting the polymer solution with a probe to draw out a polymer filament, and fixing the polymer filament on a substrate; S30: evaporating metal on the substrate to form an electrode; S40: washing away the polymer filament on the substrate to obtain a field-effect transistor; wherein the mass ratio of polymethyl methacrylate to polystyrene is (1-3):1. The present invention utilizes the polymer filament to prepare a field-effect transistor having a micro-nano-sized channel. The method is simple to operate, low in cost, and the prepared field-effect transistor having a micro-nano-sized channel has good performance.

Description

Technical Field

[0001] The present invention relates to the technical field of transistors, and in particular to a field effect transistor and a method for preparing the same. Background Art

[0002] A field-effect transistor (FET) is a semiconductor device that uses the electric field effect of a controlled input circuit to control the current in an output circuit. With the advancement of technology, the use of FETs is expanding, and the market is demanding FETs with micro- and nano-sized channels.

[0003] When manufacturing field-effect transistors with micro- and nano-sized channels, photolithography is commonly used. However, this technique requires specific masks and is cumbersome to prepare. Furthermore, the photoresist used in photolithography can corrode materials, affecting the performance of the transistor. Electron beam lithography, on the other hand, is more precise, but expensive and inefficient. Therefore, a low-cost, simple-to-use method for fabricating field-effect transistors with micro- and nano-sized channels is urgently needed. Summary of the Invention

[0004] The present invention utilizes polymer filaments to prepare field effect transistors with micro-nano sized channels, which has simple operation, good stability, and low cost. The prepared field effect transistors with micro-nano sized channels have good performance, providing a reliable and stable method for preparing metal electrodes.

[0005] To solve the above problems, the present invention provides a method for preparing a field effect transistor, comprising:

[0006] S10: mixing raw materials including polymethyl methacrylate and polystyrene to prepare a polymer solution;

[0007] S20: contacting the polymer solution with a probe, pulling out the polymer filaments, and fixing the polymer filaments on the substrate;

[0008] S30: evaporating metal on the substrate to form an electrode;

[0009] S40: washing away the polymer filaments on the substrate to obtain a field effect transistor;

[0010] Wherein, the mass ratio of polymethyl methacrylate to polystyrene is (1-3):1.

[0011] Compared with the prior art, the technical effect achieved by adopting this technical solution is: a field-effect transistor with a micro-nano-sized channel can be prepared simply and efficiently. Step S10 is to prepare a polymer material by mixing polymethyl methacrylate and polystyrene to obtain a polymer solution that can be drawn into a filament, wherein the mass ratio of polymethyl methacrylate to polystyrene is (1-3):1. In step S20, a probe is used to draw a polymer filament from the polymer solution prepared in step S10, and the polymer filament is fixed to a substrate to form a channel. After the polymer filament is evaporated with metal and then dissolved, it will be washed away. Therefore, the polymer filament can be used to block the part of the substrate where the metal is not to be evaporated. The shape of the polymer filament on the substrate can be planned according to the design of the field-effect transistor. Step S30 is to evaporate metal on the substrate, and then form a metal electrode on the substrate. The type of metal can be selected and changed according to the design of the field-effect transistor. Step S40 is to wash away the polymer filament on the substrate used to block the evaporated metal, leaving a channel with the same shape as the polymer filament, and finally obtain a field-effect transistor. Since the diameter of the polymer filament drawn in step S20 is relatively small, at the micron or nanometer level, the resulting channel on the field effect transistor is also at the micron or nanometer level, which can meet the requirements for preparing field effect transistors with micro-nano sized channels. Through the above preparation steps, a field effect transistor with a micro-nano sized channel can be prepared. Moreover, the above preparation method has a simple preparation process and is easy to operate. The polymer solution used will not affect other materials in the transistor. Therefore, the above preparation method can simply and efficiently prepare a field effect transistor with a micro-nano sized channel.

[0012] In one embodiment of the present invention, S10 includes:

[0013] S11: Mixing polymethyl methacrylate and phenyl ether to obtain a polymethyl methacrylate solution with a mass volume fraction of 10%;

[0014] S12: Mixing polystyrene and toluene to obtain a polystyrene solution with a mass volume fraction of 10%;

[0015] S13: Mixing the polymethyl methacrylate solution and the polystyrene solution to obtain a polymer solution.

[0016] Compared with the prior art, the technical effect achieved by this technical solution is as follows: a polymer solution is prepared. A phenyl ether solution can dissolve polymethyl methacrylate solids. Mixing 5 milliliters of the phenyl ether solution with 0.5 grams of polymethyl methacrylate solids yields a 10% polymethyl methacrylate solution by mass volume. A toluene solution can dissolve polystyrene solids. Mixing 5 milliliters of the toluene solution with 0.5 grams of polystyrene solids yields a 10% polystyrene solution by mass volume. The 10% polymethyl methacrylate solution and the 10% polystyrene solution by mass volume are mixed in a volume ratio of (1-3):1 to obtain a polymer solution. Using the polymer solution configured as described above, polymer filaments are drawn. The resulting polymer filaments have excellent shielding properties. After metal is evaporated onto the substrate, the metal deposited on the polymer filaments is washed away as the polymer filaments dissolve, and the portions obscured by the polymer filaments are not covered by the metal. After removing the polymer filaments, the part not covered by the metal forms a channel, forming an electrode on the transistor.

[0017] Preferably, a polymethyl methacrylate solution with a mass volume fraction of 10% and a polystyrene solution with a mass volume fraction of 10% are mixed in a volume ratio of 2:1 to obtain a polymer solution.

[0018] In one embodiment of the present invention, S20 includes:

[0019] S21: contacting a first probe with a polymer solution to draw out a polymer filament, and placing the polymer filament on a substrate and an upper side of the two-dimensional material on the substrate;

[0020] S22: Using a second probe to press the polymer filaments, the polymer filaments are fixed on the substrate.

[0021] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: laying polymer filaments on a substrate and firmly fixing the polymer filaments on the substrate. When laying the polymer filaments, first fix the substrate on a probe station, find the position where the metal electrode needs to be prepared under a microscope, that is, the position of the two-dimensional material, and the two-dimensional material has been pre-fixed on the substrate. At a position a certain distance away from the two-dimensional material, use a rubber-tipped dropper to adhere the polymer solution to the substrate, wait for the polymer solution to become viscous, take a first probe to contact the polymer solution, so that the tip of the first probe is covered with the polymer solution, lift the first probe, pull out the polymer filaments, move the probe station base, so that the polymer filaments move to the two-dimensional material and the substrate near the two-dimensional material and hang in the air, slowly lower the first probe, and lay the polymer filaments on the two-dimensional material and the substrate near it to form a channel. A second probe is used to press the end of the polymer filament in contact with the first probe. The first probe is lifted to separate the first probe from the polymer filament. The second probe is simultaneously pressed down to fix the polymer filament to the substrate. Finally, the second probe is lifted to separate the second probe from the polymer filament. The polymer filament is firmly fixed to the substrate and will not separate from the substrate under the evaporation environment. The first and second probes can be pullers.

[0022] In one embodiment of the present invention, the two-dimensional material includes at least one of graphene and transition metal chalcogenide.

[0023] Compared to existing technologies, this technical solution achieves the following technical benefits: smaller transistors can be produced. Since the successful exfoliation of graphene, 2D atomically layered materials have been proven to be stable under ambient conditions, opening up a new field in physics. Characterizing their electrical properties has become one of the key tools for our in-depth understanding of 2D materials. Therefore, methods for characterizing electrical properties are crucial. Using graphene, transition metal chalcogenides, and other 2D materials as substrates can effectively reduce the size of transistors without compromising their performance.

[0024] In one embodiment of the present invention, the substrate includes a silicon layer and a substrate layer, the substrate layer includes at least one of a silicon dioxide layer, an aluminum oxide layer, and a gallium nitride layer, and the thickness of the substrate layer is 90 nanometers to 300 nanometers.

[0025] Compared with the existing technology, the technical effect achieved by adopting this technical solution is that it plays the role of supporting the components of the transistor. The silicon layer is the bottom layer of the substrate, and the underlayer is arranged on the upper side of the silicon layer. The underlayer includes at least one of silicon dioxide, aluminum oxide, and gallium nitride, wherein the thickness of the underlayer is 90 nanometers to 300 nanometers. The underlayer mainly serves as an insulating layer and a connecting layer. Components such as two-dimensional materials and metal electrodes are arranged on the upper side of the underlayer to form the entire transistor. Therefore, the substrate plays the role of supporting the components of the transistor.

[0026] In one embodiment of the present invention, S30 includes:

[0027] S31: heating the substrate to make the polymer filaments closely adhere to the substrate;

[0028] S32: evaporating metal onto the substrate to form an electrode on the substrate;

[0029] The temperature of the heated substrate is 90° C. to 110° C.

[0030] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: strengthening the connection between the substrate and the polymer filaments. After the polymer filaments are laid on the substrate in S20, the connection between the polymer filaments and the substrate is not very stable. Under the evaporation environment, the position and shape of the polymer filaments will change to a certain extent. However, after the substrate with the polymer filaments is heated at a temperature of 90°C to 110°C for a period of time, the polymer filaments enter a highly elastic state. Under the action of their own gravity, the polymer filaments are more closely attached to the substrate, so that the shape of the polymer filaments on the substrate will not change under the evaporation environment. When evaporating metal onto the substrate, an evaporation machine is used for operation.

[0031] Preferably, the polymer filaments are heated at 100° C. for 2 minutes so that the polymer filaments are closely attached to the substrate.

[0032] In one embodiment of the present invention, the electrode includes: at least one of a gold electrode, a nickel electrode, a platinum electrode, a tungsten electrode, and an indium electrode; and / or the diameter of the polymer filament is 1 um to 100 um.

[0033] Compared with the prior art, the technical effect achieved by adopting this technical solution is: a field effect transistor with excellent performance is prepared. To prepare a metal electrode including at least one of a gold electrode, a nickel electrode, a platinum electrode, a tungsten electrode, and an indium electrode, it is necessary to place at least one of gold, nickel, platinum, tungsten, and indium metals into an evaporation machine to evaporate the required metal electrode according to the design during evaporation in S30, or place a metal alloy containing at least two of gold, nickel, platinum, tungsten, and indium into the evaporation machine to obtain a metal electrode. As needed, metal electrodes with multiple different metal components can be set on one substrate. By setting the diameter of the polymer filament to 1um to 100um, a micro-nano sized channel of 1um to 100um can be obtained, and then a field effect transistor with a micro-nano sized channel can be obtained. By setting the field effect transistor as described above, the prepared field effect transistor can have excellent performance. Preferably, the diameter of the polymer filament is between 5um and 50um.

[0034] In one embodiment of the present invention, S40 includes:

[0035] S41: placing the substrate into a stripping solution to wash away the polymer filaments on the substrate;

[0036] S42: Cleaning the substrate to obtain a field effect transistor.

[0037] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: washing away the polymer filaments on the substrate. After the metal is evaporated, the polymer filaments need to be washed away to obtain the channel. The evaporated substrate is placed in a stripping solution and shaken slightly, and the polymer filaments can be seen to dissolve and fall off the substrate. After stripping the polymer filaments, there will still be stripping solution and polymer filament residues on the substrate, so the substrate is cleaned again with anhydrous ethanol, and finally a clean field-effect transistor is obtained.

[0038] In one embodiment of the present invention, the stripping solution includes at least one of benzene, toluene, xylene, acetone, and tetrahydrofuran.

[0039] Compared with existing technologies, this technical solution achieves the following technical effects: better removal of polymer filaments. Polymer filaments are polymer materials that are difficult to remove using ordinary cleaning solvents. Benzene, toluene, xylene, acetone, and tetrahydrofuran have good solubility for polymer materials. After placing the substrate in a benzene, toluene, xylene, acetone, or tetrahydrofuran solution, the polymer dissolves or decomposes, effectively removing the polymer filaments from the substrate. Furthermore, benzene, toluene, xylene, acetone, and tetrahydrofuran do not affect components such as the substrate and metal electrodes.

[0040] The present invention also provides a field effect transistor, which is prepared by the above preparation method.

[0041] Compared with existing technologies, the technical effects achieved by adopting this technical solution are: smaller size and excellent performance. The field-effect transistor prepared by the above preparation method has a very small size, suitable for use in various scenarios. In addition, the channel set on the field-effect transistor is at the micron or nanometer level, which can effectively improve the performance of the field-effect transistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of a substrate heated at 100° C. during the preparation process of an embodiment of the present invention.

[0043] Figure 2 This is an optical microscope photograph of a substrate after polymer filaments are laid on the substrate according to an embodiment of the present invention.

[0044] Figure 3 This is an optical microscope photograph of the substrate after metal evaporation and removal of polymer filaments in an embodiment of the present invention.

[0045] Figure 4 This is an IV test diagram of the field effect transistor prepared in an embodiment of the present invention.

[0046] Figure 5 A schematic diagram of the steps for preparing a field effect transistor provided in an embodiment of the present invention.

[0047] Figure 6 A schematic diagram of another field effect transistor preparation step provided in an embodiment of the present invention.

[0048] Figure 7 A schematic diagram of another field effect transistor preparation step provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0050] Example 1:

[0051] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0052] S10: dissolving 0.5 g of polymethyl methacrylate solid in 5 ml of phenylethyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolving 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mixing the prepared polymethyl methacrylate solution and the polystyrene solution in a ratio of 3:1 to form a polymer;

[0053] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station, find the two-dimensional material on which the metal electrode needs to be prepared under a microscope, drop a mixed polymer on the silicon wafer 500um away from the two-dimensional material, and then slowly place probe 1 on the probe station into the polymer so that the needle tip is covered with the polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of the two-dimensional material and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2, lift up probe 1 to break the polymer wire, and at the same time continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0054] S30: Place the silicon wafer on a heating table and heat it at 90°C for 2 minutes. Under a microscope, it is observed that the polymer thin wires can be closely attached to the silicon wafer, and the width of the thin wires is about 1 μm.

[0055] S40: Place the silicon wafer with the polymer wires drawn into the vapor deposition machine, add different metals to vapor-deposit the required metal electrodes as needed, or add multiple metal vapor deposition alloys at the same time;

[0056] S50: Place the silicon wafer with the electrode deposited into the benzene solution and shake it slightly. You can see the process of polymer dissolution until the polymer on the material is removed. After taking it out of the benzene solution, rinse it with anhydrous ethanol.

[0057] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0058] Example 2:

[0059] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0060] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0061] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station, find the two-dimensional material on which the metal electrode needs to be prepared under a microscope, drop a mixed polymer on the silicon wafer 500um away from the two-dimensional material, and then slowly place probe 1 on the probe station into the polymer so that the needle tip is covered with the polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of the two-dimensional material and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2, lift up probe 1 to break the polymer wire, and at the same time continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0062] S30: Place the silicon wafer on a heating table and heat it at 100°C for 2 minutes. Under a microscope, it is observed that the polymer wires are closely attached to the silicon wafer, and the width of the wires is about 10 μm.

[0063] S40: Place the silicon wafer with the polymer wires drawn into the vapor deposition machine, add different metals to vapor-deposit the required metal electrodes as needed, or add multiple metal vapor deposition alloys at the same time;

[0064] S50: Place the silicon wafer with the electrode deposited into the toluene solution and shake it slightly. You can see the polymer dissolving process until the polymer on the material is removed. After taking it out of the toluene solution, rinse it with anhydrous ethanol.

[0065] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0066] Example 3:

[0067] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0068] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 1:1 to form a polymer.

[0069] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station, find the two-dimensional material on which the metal electrode needs to be prepared under a microscope, drop a mixed polymer on the silicon wafer 500um away from the two-dimensional material, and then slowly place probe 1 on the probe station into the polymer so that the needle tip is covered with the polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of the two-dimensional material and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2, lift up probe 1 to break the polymer wire, and at the same time continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0070] S30: Place the silicon wafer on a heating table and heat it at 110°C for 2 minutes. Under a microscope, it is observed that the polymer thin wires are closely attached to the silicon wafer, and the width of the thin wires is about 100 μm.

[0071] S40: Place the silicon wafer with the polymer wires drawn into the vapor deposition machine, add different metals to vapor-deposit the required metal electrodes as needed, or add multiple metal vapor deposition alloys at the same time;

[0072] S50: Place the silicon wafer with the electrode deposited in a xylene solution and shake it slightly. You can see the polymer dissolving process until the polymer on the material is removed. After taking it out of the xylene solution, rinse it with anhydrous ethanol.

[0073] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0074] Example 4:

[0075] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0076] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0077] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station. Under a microscope, find the two-dimensional material GeSe on which the metal electrode needs to be prepared. Drop the mixed polymer on the silicon wafer 500um away from the two-dimensional material GeSe. Then slowly place probe 1 on the probe station in the polymer so that the needle tip is covered with polymer. Lift up probe 1 and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to and hangs above the two-dimensional material GeSe. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2. Lift up probe 1 to break the polymer wire and continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire. The optical microscope photo of the silicon wafer after laying the polymer is as shown below. Figure 2 As shown;

[0078] S30: Figure 1 As shown, the silicon wafer was placed on a heating table and heated at 100°C for 2 minutes. Under a microscope, it was observed that the polymer thin wires were able to adhere closely to the silicon wafer, and the width of the thin wires was about 10 μm.

[0079] S40: Place the silicon wafer with the polymer wire drawn on it into the vapor deposition machine, add gold, and vapor-deposit the required gold electrodes;

[0080] S50: Place the silicon wafer with the electrode deposited into the toluene solution and shake it slightly. You can see the process of polymer dissolution until the polymer on GeSe is removed. After taking it out of the toluene solution, rinse it with anhydrous ethanol to keep the material on the silicon wafer clean and remove organic contamination. The optical microscope photo of the silicon wafer after removing the polymer is as follows: Figure 3 shown.

[0081] This embodiment also provides a field effect transistor, which is prepared by the above preparation method. The IV test results of the field effect transistor are as follows: Figure 4 As shown. Figure 4 It can be seen that the metal electrode evaporated by the polymer wire to form the channel has good contact with the material.

[0082] Embodiment 5:

[0083] like Figure 5 As shown, this embodiment provides a method for preparing a field effect transistor, which can be used to prepare a nine-grid electrode. The preparation steps are as follows:

[0084] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0085] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station. Under a microscope, find the two-dimensional material GeSe2 on which the metal electrode needs to be prepared. Drop the mixed polymer on the left side of the silicon wafer, 500um away from GeSe2. Then slowly place probe 1 on the probe station in the polymer so that the needle tip is covered with polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to and is suspended above GeSe2. Probe 1 is on the right side of GeSe2. Slowly lower probe 1 to press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2. Lift up probe 1 to break the polymer wire. At the same time, continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0086] S30: Repeat the above steps three times until three polymer lines are drawn on the two-dimensional material GeSe2, and place the silicon wafer on a heating table and heat it at 100°C for 2 minutes to perform a heat bonding process so that the polymer can be better bonded to the material;

[0087] S40: Take out the silicon wafer with the polymer bonded, place it on the probe station in the direction of the original silicon wafer, then drop the polymer to the lower side of GeSe2 500um, then slowly place probe 1 in the polymer so that the needle tip is covered with polymer, lift probe 1, you can see a polymer wire being pulled out, move the probe station base so that the polymer wire moves to the top of GeSe2 and is suspended in the air, with probe 1 on the right side of GeSe2, slowly lower probe 1 to press the polymer wire on the silicon wafer, press the end of the polymer wire with probe 2, lift probe 1 to break the polymer wire, and continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer, and finally separate probe 2 from the polymer wire;

[0088] S50: Repeat the above steps three times until three polymer lines are drawn on the material again. The silicon wafer is placed on the heating table and heated at 100°C for 2 minutes. Under a microscope, it is observed that the polymer lines are closely attached to the silicon wafer, and the width of the lines is about 10 μm.

[0089] S60: Place the silicon wafer with the polymer wire drawn on it into the vapor deposition machine, add gold, and vapor-deposit the required gold electrodes;

[0090] S70: Place the silicon wafer with the electrode evaporated into the toluene solution and shake it slightly. You can see the process of polymer dissolution until the polymer on GeSe2 is removed. After taking it out of the toluene solution, rinse it with anhydrous ethanol to keep the material on the silicon wafer clean and remove organic contamination.

[0091] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0092] The above preparation method is equivalent to building nine metal electrodes on GeSe2, and its electrical performance can be tested in different orientations or by selecting different channel widths.

[0093] Example 6:

[0094] like Figure 6 As shown, this embodiment provides a method for preparing a field effect transistor, which can be used to prepare a heterojunction electrode. The preparation steps are as follows:

[0095] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0096] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station. Under a microscope, find the heterojunction (GeSe-MoS2) where the metal electrode needs to be prepared. Drop the mixed polymer on the silicon wafer 500um away from GeSe. Then slowly place probe 1 on the probe station in the polymer so that the needle tip is covered with polymer. Lift up probe 1 and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of GeSe and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2. Lift up probe 1 to break the polymer wire. At the same time, continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, separate probe 2 from the polymer wire.

[0097] S30: Slowly place probe 1 in the polymer again so that the needle tip is covered with polymer. Lift probe 1 and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of GeSe-MoS2 and hangs in the air. Slowly lower probe 1 to press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2. Lift probe 1 to break the polymer wire. At the same time, continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0098] S40: Slowly place probe 1 in the polymer again so that the needle tip is covered with polymer. Lift probe 1 and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of MoS2 and hangs in the air. Slowly lower probe 1 to press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2. Lift probe 1 to break the polymer wire. At the same time, continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0099] S50: Place the silicon wafer on a heating table and heat it at 100°C for 2 minutes. Under a microscope, it is observed that the polymer wires are closely attached to the silicon wafer, and the width of the wires is about 10 μm.

[0100] S60: Place the silicon wafer with the polymer wire drawn on it into the vapor deposition machine, add gold, and vapor-deposit the required gold electrodes;

[0101] S70: Place the silicon wafer with the electrode deposited in a toluene solution and shake it slightly. You can see the polymer dissolving process until the polymer on the material is removed. After taking it out of the toluene solution, rinse it with anhydrous ethanol to keep the material on the silicon wafer clean and remove organic contamination.

[0102] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0103] After using the above method to make electrodes, the electrical properties of GeSe and MoS2 can be tested individually, and the performance of the heterojunction part can also be tested. Compared with photolithography electrode technology, the above method is more efficient and more convenient.

[0104] Embodiment seven:

[0105] like Figure 7 As shown, this embodiment provides a method for preparing a field effect transistor, which can evaporate different metals. The preparation steps are as follows:

[0106] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0107] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station. Under a microscope, find the two-dimensional material GeSe2 on which different metal electrodes need to be prepared. Drop a mixed polymer on the silicon wafer 500um away from GeSe2, and then slowly place probe 1 on the probe station in the polymer so that the needle tip is covered with polymer. Lift up probe 1, and you can see a polymer wire being pulled out. The diameter of the polymer wire is 100um. Move the base of the probe station so that the polymer wire moves to and is suspended above GeSe2. At this time, the polymer wire slowly descends probe 1 5um to the right of the center of the two-dimensional material GeSe2, presses the polymer wire on the silicon wafer, presses the end of the polymer wire with probe 2, lifts up probe 1 to break the polymer wire, and at the same time, continues to descend probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0108] S30: Place the silicon wafer on a heating table and heat it at 100°C for 2 minutes to heat and bond it. Place the silicon wafer with the polymer wires drawn on it into a vapor deposition machine, add nickel, vapor-deposit the nickel electrode, and wash away the polymer wires.

[0109] S40: Using the same method, a 100-un-wide polymer wire is drawn 5 μm to the left of the center of the two-dimensional material GeSe2. The silicon wafer is placed on a heating table and heated at 100°C for 2 minutes to heat and bond. The silicon wafer with the drawn polymer wire is placed in an evaporation machine, and gold is added to evaporate a gold electrode.

[0110] S50: Place the silicon wafer with the electrode deposited in a toluene solution and shake it slightly. You can see the process of polymer dissolution until the polymer on GeSe2 is removed. After taking it out of the toluene solution, rinse it with anhydrous ethanol to keep the material on the silicon wafer clean and remove organic contamination.

[0111] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0112] Embodiment 8:

[0113] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0114] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0115] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station, find the two-dimensional material on which the metal electrode needs to be prepared under a microscope, drop a mixed polymer on the silicon wafer 500um away from the two-dimensional material, and then slowly place probe 1 on the probe station into the polymer so that the needle tip is covered with the polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of the two-dimensional material and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2, lift up probe 1 to break the polymer wire, and at the same time continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0116] S30: Place the silicon wafer on a heating table and heat it at 100°C for 2 minutes. Under a microscope, it is observed that the polymer wires are closely attached to the silicon wafer, and the width of the wires is about 50 μm.

[0117] S40: Place the silicon wafer with the polymer wires drawn into the vapor deposition machine, add different metals to vapor-deposit the required metal electrodes as needed, or add multiple metal vapor deposition alloys at the same time;

[0118] S50: Place the silicon wafer with the electrode deposited in the acetone solution and shake it slightly. You can see the process of polymer dissolution until the polymer on the material is removed. After taking it out of the acetone solution, rinse it with anhydrous ethanol.

[0119] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0120] Embodiment 9:

[0121] This embodiment provides a method for manufacturing a field effect transistor, comprising:

[0122] S10: Dissolve 0.5 g of polymethyl methacrylate solid in 5 ml of phenyl ether solution to prepare a polymethyl methacrylate solution with a mass volume fraction of 10%, then dissolve 0.5 g of polystyrene solid in 5 ml of toluene solution to prepare a polystyrene solution with a mass volume fraction of 10%, and finally, mix the prepared polymethyl methacrylate solution and polystyrene solution in a ratio of 2:1 to form a polymer.

[0123] S20: Take a silicon wafer including a silicon dioxide layer and a silicon layer and fix it on the probe station, find the two-dimensional material on which the metal electrode needs to be prepared under a microscope, drop a mixed polymer on the silicon wafer 500um away from the two-dimensional material, and then slowly place probe 1 on the probe station into the polymer so that the needle tip is covered with the polymer. Lift up probe 1, and you can see a polymer wire being pulled out. Move the probe station base so that the polymer wire moves to the top of the two-dimensional material and hangs in the air. Slowly lower probe 1 and press the polymer wire on the silicon wafer. Press the end of the polymer wire with probe 2, lift up probe 1 to break the polymer wire, and at the same time continue to lower probe 2 so that the polymer wire contacted by probe 2 is firmly fixed on the silicon wafer. Finally, probe 2 is separated from the polymer wire.

[0124] S30: Place the silicon wafer on a heating table and heat it at 100°C for 2 minutes. Under a microscope, it is observed that the polymer thin wires can be closely attached to the silicon wafer, and the width of the thin wires is about 15 μm.

[0125] S40: Place the silicon wafer with the polymer wires drawn into the vapor deposition machine, add different metals to vapor-deposit the required metal electrodes as needed, or add multiple metal vapor deposition alloys at the same time;

[0126] S50: Place the silicon wafer with the electrode deposited in a tetrahydrofuran solution and shake it slightly. You can see the polymer dissolving process until the polymer on the material is removed. After taking it out of the tetrahydrofuran solution, rinse it with anhydrous ethanol.

[0127] This embodiment also provides a field effect transistor, which is prepared by the above preparation method.

[0128] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the claims.

Claims

1. A method for preparing a field effect transistor, characterized in that: include: S10: Mixing raw materials including polymethyl methacrylate and polystyrene to prepare a polymer solution liquid; S20: contacting the polymer solution with a probe to draw out polymer filaments, and fixing the polymer filaments on a substrate; S30: evaporating metal on the substrate to form an electrode; S40: washing away the polymer filaments on the substrate to obtain the field effect transistor; wherein the mass ratio of the polymethyl methacrylate to the polystyrene is (1-3):1; The S20 includes: S21: contacting the polymer solution with a first probe, pulling out the polymer filament, and placing the polymer filament on the substrate and the upper side of the two-dimensional material on the substrate; S22: Using a second probe to press the polymer filament to fix the polymer filament on the substrate; The substrate includes a silicon layer and a substrate layer, the substrate layer includes at least one of a silicon dioxide layer, an aluminum oxide layer, and a gallium nitride layer, and the thickness of the substrate layer is 90 nanometers to 300 nanometers; The electrode comprises: at least one of a gold electrode, a nickel electrode, a platinum electrode, a tungsten electrode, and an indium electrode; The diameter of the polymer filaments is between 1um and 100um.

2. The preparation method according to claim 1, characterized in that The S10 includes: S11: taking the polymethyl methacrylate and phenyl ether and mixing them to obtain a mass volume fraction of 10% polymethyl methacrylate solution; S12: mixing the polystyrene with toluene to obtain a polystyrene solution with a mass volume fraction of 10%; S13: mixing the polymethyl methacrylate solution and the polystyrene solution to obtain the polymer solution.

3. The preparation method according to claim 1, characterized in that The two-dimensional material includes at least one of graphene and transition metal chalcogenide.

4. The preparation method according to claim 1, characterized in that The S30 includes: S31: heating the substrate to closely adhere the polymer filaments to the substrate; S32: evaporating metal onto the substrate to form the electrodes on the substrate; The substrate is heated at a temperature of 90° C. to 110° C.

5. The preparation method according to claim 1, characterized in that The S40 includes: S41: placing the substrate into a stripping solution to wash away the polymer filaments on the substrate; S42: Cleaning the substrate to obtain the field effect transistor.

6. The preparation method according to claim 5, characterized in that The stripping solution includes at least one of benzene, toluene, xylene, acetone, and tetrahydrofuran.

7. A field effect transistor, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 6.

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