A method for fabricating a short channel transistor using a hard tip

Abstract

The application discloses a method for preparing a short channel transistor by using a hard needle tip, belongs to the field of transistor processing technology, and aims at solving the technical problems that the preparation method of a short channel electrode is complex and the precision of the shape of the short channel electrode needs to be further improved in the prior art. The application comprises the following steps: arranging a supporting layer on an adhesive layer to obtain a substrate layer decorated by a composite architecture layer composed of a short channel electrode / adhesive layer / supporting layer. A negative photoresist with high leveling performance and high adhesion is prepared. After curing, the high flatness makes the ultraviolet photoetching uniform and efficient, improves the accuracy of patterning, and further improves the resolution of the electrode layer. Meanwhile, the negative photoresist prepared by the application is matched with the method for preparing a short channel transistor by using a hard needle tip provided by the application, so that the complexity of preparing the short channel transistor is reduced, and the precision of the short channel electrode structure is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of transistor processing technology, and particularly relates to a method for preparing a short channel transistor by using a hard needle tip. BACKGROUND

[0002] With the advent of the post-Moore era, the research and preparation process of short channel devices are increasingly concerned, because of the urgent needs of improving the performance of semiconductor devices, increasing the integration of devices and reducing power consumption, etc. By reducing the channel length and the cross-sectional area of the channel, the short channel device can minimize the electron transport path, reduce the resistance and power consumption of the device, and improve the on-state current and performance of the device. Therefore, the development of the process for preparing short channel devices not only helps to realize higher performance electronic devices, but also has important significance for promoting the progress and application of micro-nano electronic technology.

[0003] In the prior art, the process of using EBL to make nanoscale short channel electrodes mainly includes three steps: photoetching, depositing electrode material and removing glue. In the photoetching process, photoresist is usually spin-coated on the surface of a suitable substrate and dried, then the photoresist is exposed to an electron beam using an EBL instrument, the substrate after exposure is immersed in a developing solution to remove the photoresist area changed by the electron beam, and a pattern is formed on the substrate.

[0004] Electron beam exposure is the key to achieving nanoscale short channels, because the electron beam can be focused to a size less than 10 nanometers, and the interaction between the electron beam and the photoresist is limited to the surface layer, meaning that the exposure process is highly localized, achieving high resolution, and the developing process also needs to strictly control the time and temperature to ensure the accuracy of the pattern. Deposition of electrode material can use physical vapor deposition, chemical vapor deposition, atomic layer deposition, etc. to deposit electrode materials such as gold, silver, copper, aluminum, etc. on the formed photoresist pattern. Finally, the photoresist and the electrode material thereon are removed, leaving the desired electrode pattern.

[0005] However, in the above-mentioned short channel electrode preparation scheme, in order to achieve nanoscale short channels, EBL technology is mainly used. However, EBL equipment is expensive and requires a special laboratory and facilities to support its operation, in addition to high-cost maintenance and operation. In addition, the preparation of short channel electrodes requires a long preparation period, because these technologies usually need to be carried out in a high vacuum environment. In addition to the need for precise preparation and processing of the sample, precise adjustment and calibration of the equipment are required, and the preparation process is complex. Therefore, although EBL technology has the advantages of high resolution and local control, its high cost, long cycle and high complexity limit its widespread application in short channel electrode preparation.

[0006] And after the photoetching is completed, the solubility of the positive photoresist at the exposed position is increased, and the developing effect is difficult to control during the developing process, if the developing time is too short, the pattern edge will not be clear, and if the developing time is too long, the unexposed position will be excessively dissolved, resulting in reduced pattern precision, so that the shape precision of the electrode layer obtained through deposition is reduced;

[0007] In summary, the method for preparing a nanoscale short channel electrode needs to be further simplified, and the precision of the electrode pattern obtained through photoetching also needs to be further improved. In view of the technical defects in this regard, a solution is proposed. SUMMARY

[0008] The present application aims to provide a method for preparing a short channel transistor using a hard needle tip, to solve the technical problems of the prior art that the preparation method of the short channel electrode is complex and the precision of the short channel electrode structure needs to be further improved.

[0009] The object of the present application can be achieved by the following technical solution: a method for preparing a short channel transistor using a hard needle tip, comprising the following steps:

[0010] S1, an electrode layer is prepared on the surface of a substrate layer, a hard needle tip is used to trench the electrode layer to produce a gap to obtain a short channel electrode to be transferred;

[0011] S2, an adhesion layer is provided on the substrate layer and the short channel electrode;

[0012] S3, a support layer is provided on the adhesion layer to obtain a substrate layer modified by a composite architecture layer composed of a short channel electrode / adhesion layer / support layer;

[0013] S4, the composite architecture is peeled off from the substrate layer to obtain a composite architecture;

[0014] S5, the layered structure is transferred to a target carrier to obtain a short channel electrode;

[0015] S6, the adhesion layer and the support layer in the composite architecture are separated, and the short channel electrode tube is obtained after post-processing.

[0016] Further, the operation of preparing the electrode layer includes determination of the shape of the electrode layer and formation of the electrode layer entity, the method used for determining the shape of the electrode layer includes ultraviolet lithography, electron beam lithography, hard mask, and nanosphere lithography, and the method used for forming the electrode layer entity includes electron beam evaporation plating, thermal evaporation plating, magnetron sputtering plating, and electrochemical deposition.

[0017] Preferably, the determination of the shape of the electrode layer selects the ultraviolet lithography method, and the formation of the electrode layer entity selects the electron beam evaporation plating method.

[0018] Further, the operation of preparing the electrode layer includes the following steps:

[0019] A1, after spin-coating the negative photoresist on the substrate layer, the substrate layer is transferred to a drying oven with a temperature of 80℃ for vacuum drying, to obtain a substrate layer with the negative photoresist attached to the surface;

[0020] A2, after irradiation exposure of the negative photoresist using a photoetching machine, the negative photoresist layer is soaked with a developing solution, to obtain a patterned photoresist surface;

[0021] A3, after surface deposition of the patterned photoresist surface using an electron beam evaporation technique, the photoresist is peeled off to obtain an electrode layer modified substrate layer.

[0022] Further, the shape of the electrode to be transferred can be arbitrarily selected according to requirements, and the material of the electrode to be transferred includes gold, silver, copper, aluminum, bismuth, target and platinum.

[0023] Further, the substrate layer includes fluorine crystal mica, silicon oxide, monocrystalline silicon, quartz, glass, sapphire, silicon nitride, aluminum nitride and carbonitride, etc.

[0024] Preferably, cleaved fluorine crystal mica is selected as the substrate layer.

[0025] Further, cleaving the fluorine crystal mica includes the following methods:

[0026] a1, using adhesive tape to stick to the two surfaces of the un-cleaved fluorine crystal mica, and then peeling off to obtain two pieces of cleaved fluorine crystal mica;

[0027] a2, using a blade to insert into the interlayer of the un-cleaved fluorine crystal mica, and then twisting the blade to divide the fluorine crystal mica into two pieces, to obtain two pieces of cleaved fluorine crystal mica;

[0028] a3, opening a gap at the edge of the fluorine crystal mica, and immersing water along the gap, the water immersed in the gap will expand the fluorine crystal mica, to obtain two pieces of cleaved mica.

[0029] Further, the preparation method of the negative photoresist is as follows: 20-30 parts of photoresist precursor, 5-10 parts of 3-aminopropyl triethoxysilane and 75-100 parts of dimethyl sulfoxide are weighed according to the weight ratio, and added into a reaction kettle, stirred at room temperature for 5-10 min, the temperature of the reaction kettle is lowered to 0-5℃, 1-2 parts of 1-hydroxybenzotriazole and 1-2 parts of dicyclohexyl carbodiimide are added, and the reaction is carried out for 1-2 h, and the negative photoresist is obtained after post-treatment.

[0030] The reaction equation for preparing the negative photoresist is as follows:

[0031]

[0032] The reaction principle for preparing the negative photoresist is that the carboxyl and carbodiimide in the photoresist precursor react to generate an active intermediate, and the amino and carboxyl nucleophilic attack generates a condensation product. Since the addition intermediate of the acid to the carbodiimide is not stable in the first stage of the reaction, the acylation catalyst 1-hydroxybenzotriazole is added to make the reaction stable and complete, and finally the negative photoresist is obtained.

[0033] Further, the post-treatment includes: after the reaction kettle is cooled to room temperature, the reaction liquid is added to a rotary evaporator with a water bath temperature of 80-100℃, and vacuum distillation is performed until no liquid is produced, so that the negative photoresist is obtained.

[0034] Further, the preparation method of the negative photoresist precursor is: 20-30 parts of 3,3'-diaminobenzophenone, 12-20 parts of 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 75-100 parts of N,N-dimethylformamide and 1-3 parts of triethylamine are weighed according to the weight parts and added to the reaction kettle, stirred at room temperature for 2-4 hours, and the negative photoresist precursor is obtained after post-treatment.

[0035] The reaction equation for preparing the negative photoresist precursor is:

[0036]

[0037] The reaction principle for preparing the negative photoresist precursor is that the amino-containing 3,3'-diaminobenzophenone nucleophilic reagent attacks the carbonyl carbon atom in the 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride molecule. The nitrogen atom of the amino group has a lone pair of electrons, and these electrons can form a new covalent bond with the carbonyl carbon atom to form a long-chain polyamic acid connected by amide groups, and finally the negative photoresist precursor is prepared.

[0038] Further, the post-treatment includes: after the reaction kettle is cooled to room temperature, the reaction liquid is added to a rotary evaporator with a water bath temperature of 80-100℃, and vacuum distillation is performed until no liquid is produced, so that the negative photoresist is obtained.

[0039] Further, in step S1, the hard needle tip used includes a scanning probe microscope needle tip such as an atomic force microscope, a scanning tunneling microscope, a chemical force microscope, a scanning electron microscope / transmission electron microscope, and a hard needle tip with a small enough curvature radius obtained by laser etching, ion etching, solution etching, mechanical grinding and the like.

[0040] In step S2, the method for setting the adhesion layer includes: spin coating an adhesion solution on the surface of the substrate layer, coating the substrate layer short channel electrode, transferring the material to a drying oven with a temperature of 80℃ for vacuum drying, and keeping the temperature for 20-40 minutes to obtain a substrate layer with an adhesion layer attached to the surface.

[0041] Further, the adhesive solution includes 15-30 wt% polymethyl methacrylate methyl ether solution, ultraviolet photoresist, 10-15 wt% polyvinyl alcohol aqueous solution, 10-20 wt% polycarbonate chloroform solution and 5-10 wt% polypropylene carbonate chloroform solution.

[0042] In step S3, the operation of arranging the support layer includes the following steps:

[0043] B1, attaching the flexible adhesive film to the thin plate to form the support layer;

[0044] B2, attaching the support layer with the flexible adhesive film on one side to the adhesive layer, transferring the material to the drying oven, increasing the temperature of the drying oven to 50℃, and maintaining the temperature for 10-15 min to arrange the support layer on the adhesive layer.

[0045] Further, in step B1, the flexible adhesive film includes polyvinyl alcohol film, polycarbonate film and polypropylene carbonate film; and the thin plate includes polydimethylsiloxane thin plate and polydimethylsiloxane / polyvinyl chloride thin plate.

[0046] Further, the thickness of the flexible film is 100-150 μm, and the thickness of the thin plate is 200-250 μm.

[0047] Further, in step S4, the operation of peeling the composite structure includes the following steps:

[0048] Further, in step S5, the operation of transferring the composite structure includes the following steps:

[0049] C1, attaching the support layer in the composite structure layer to the glass sheet, and using the transfer table to attach the composite structure layer to the target carrier;

[0050] C2, applying a pressure of 200-300 Pa while heating the bonding interface, the heating temperature is 140-150℃, and maintaining for 5-10 min to obtain a short channel electrode.

[0051] Further, the target carrier includes a rigid carrier and a flexible carrier, the material of the rigid carrier includes silicon oxide, single crystal silicon and diamond; and the flexible carrier is polydimethylsiloxane.

[0052] Further, the target carrier has a pre-prepared thin layer structure on the surface, and the thin layer structure includes a metal electrode, a metal antenna and a two-dimensional material.

[0053] Optionally, the target carrier has a three-dimensional structure with a certain height on the surface.

[0054] Further, in step S6, the operation of separating the adhesion layer and the support layer in the composite structure comprises: transferring the short channel precursor into a dissolving solution for 5-10 min, collecting the support layer after the adhesion layer is dissolved, and obtaining a short channel transistor precursor.

[0055] Further, in step S6, the post-processing operation comprises: placing the material in a drying box with a temperature of 50-60 DEG C, taking nitrogen as the atmosphere, and drying until the material has a constant weight, to obtain a short channel transistor.

[0056] Further, in step S6, the dissolving solution comprises acetone, water, and chloroform.

[0057] Optionally, steps S1-S6 are repeatedly performed on the same target carrier to obtain a combination structure of multiple electrodes.

[0058] The present application has the following advantages:

[0059] 1、The present application uses a hard needle tip to operate the electrode in the process of preparing a short channel transistor with a hard needle tip, so as to obtain a short channel electrode. Compared with the scheme of EBL for preparing a short channel electrode, the price of the hard needle tip is very low, and the learning cost and maintenance cost of the instrument are also low. Moreover, the present application can be realized at room temperature in an atmospheric environment, which greatly reduces the threshold for obtaining a short channel electrode. Meanwhile, in the process of preparing a combination structure of multiple electrodes by EBL technology, the scrap rate of each link is cumulative. However, the present application uniformly disperses the scrap rate of each electrode in multiple parallel links, which greatly improves the yield of the combination structure of multiple electrodes. In the step of soaking the target carrier in the dissolving solution, the electrode material damaged in the process of cutting the electrode layer by the hard needle tip is accumulated on both sides of the channel, which may affect the performance of the short channel electrode and may also cause short circuit. After the composite structure layer is combined, the short channel electrode is firmly attached to the target carrier by heating. At this time, the accumulated electrode material on the upper surface of the short channel electrode is adhered by the adhesion layer. Therefore, the accumulated electrode material on both sides of the channel is removed together when the adhesion layer is removed by acetone soaking, so as to avoid the influence of the accumulated electrode material on the short channel electrode, and further improve the yield of the short channel transistor.

[0060] 2. This invention's method for fabricating short-channel transistors using hard tips offers the following improvements over EBL technology. EBL technology directly fabricates short-channel electrodes on the target substrate, a cumbersome and time-consuming process. Typically, the target sample is first grown / peeled / stacked on the target carrier, and then the short-channel electrodes are fabricated on top to form a complete device. Therefore, there is a significant time lag between preparing the target sample and forming the complete device. This invention combines short-channel electrode fabrication with electrode transfer, allowing the composite structure layer to be prepared in advance. Only a transfer-peeling operation is needed to transfer the short-channel electrodes to the target carrier when required, greatly shortening the time required to fabricate the complete device. EBL technology requires sequentially fabricating different electrodes on the same target carrier to form electrode structures with different electrode materials, which is time-consuming. This invention combines short-channel electrode fabrication with electrode transfer, allowing for repeated operations on different substrates in advance to prepare electrodes with different patterns and materials. The desired electrode structure, including combinations of multiple electrode materials, can be obtained on the target carrier in a short time through repeated transfer-peeling operations.

[0061] 3. In the process of fabricating short-channel transistors using a hard tip, this invention first prepares a negative photoresist with a benzophenone structure. Under ultraviolet irradiation, the carbonyl group of the ketone is excited, thereby abstracting hydrogen from the side-chain alkyl group to generate a hydroxyl group and a carbon-carbon single bond, thus achieving a cross-linked structure. This makes the exposed area difficult to dissolve in the developer, resulting in a negative photolithography pattern. Simultaneously, the negative photoresist is further modified with a silane coupling agent, which enhances its cross-linking ability with the substrate. The leveling properties provided by the siloxane segments make the negative photoresist more uniformly dispersed, resulting in a more uniform and efficient photolithography effect. Because after photolithography, the negative photoresist is irradiated... The cross-linking of the internal organic structure significantly reduces the solubility at that location. Compared to the mechanism by which positive photoresist increases the solubility of the irradiated area, positive photoresist requires stricter control over development time and temperature. Short development time leads to insufficient development, while long development time leads to excessive dissolution of the positive photoresist, ultimately resulting in the patterned photoresist surface not meeting the required precision. However, due to its mechanism of reducing the solubility of the exposed area, negative photoresist can fully develop the pattern in the unexposed area by extending the development time without excessive dissolution, thereby improving the precision of the short-channel electrode shape and increasing the product yield. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 Flow chart for preparation of short channel electrode of the present application;

[0065] Figure 2 Schematic diagram of surface flat substrate layer;

[0066] Figure 3 Schematic diagram of electrode layer fabrication on the surface of the substrate layer;

[0067] Figure 4 Schematic diagram of operation on the surface of the electrode layer using hard tip;

[0068] Figure 5 Schematic diagram of the electrode layer with gap becoming short channel electrode;

[0069] Figure 6 Schematic diagram of adhesion layer setting on the surface of the substrate layer and the short channel electrode;

[0070] Figure 7 Schematic diagram of support layer setting on the surface of the adhesion layer;

[0071] Figure 8 Schematic diagram of the composite architecture layer peeling from the surface of the substrate;

[0072] Figure 9 Schematic diagram of the composite architecture layer adhering to the target substrate;

[0073] Figure 10 Schematic diagram of the support layer removing from the composite architecture layer;

[0074] Figure 11 Schematic diagram of the adhesion layer removing from the target carrier composed of the laminated structure, resulting in the short channel electrode tube side view.

[0075] In the figure: 1, substrate layer; 2, electrode layer; 3, hard tip; 4, short channel electrode; 5, adhesion layer; 6, support layer; 7, target carrier. DETAILED DESCRIPTION

[0076] The technical solutions of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0077] The positive photoresist used in the present application is purchased from Shenzhen Lunsing Technology Co., Ltd., with model AZ 1500;

[0078] The fluorine crystal mica used in the application is purchased from Hefei Kejin Material Technology Co., Ltd., and the model is KMg3(AlSi3O10)F2.

[0079] The polyvinyl alcohol used in the application is purchased from Nanjing Chemical Reagent Co., Ltd., and the model is 1788.

[0080] Example 1

[0081] The embodiment is used to provide a method for preparing a short channel transistor by using a hard needle tip, comprising the following steps:

[0082] S1, preparing a negative photoresist

[0083] 13.4g of 3,3'-diaminobenzophenone, 8.6g of 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 38.3g of N,N-dimethylformamide and 1.0g of triethylamine are weighed and added into a reaction kettle, stirred at room temperature for 2h, and then treated to obtain 21.3g of a negative photoresist precursor;

[0084] 20.0g of the photoresist precursor, 5.0g of 3-aminopropyl triethoxysilane and 80.0g of dimethyl sulfoxide are weighed and added into a reaction kettle, stirred at room temperature for 5min, the temperature of the reaction kettle is lowered to 5℃, 1.0g of 1-hydroxybenzotriazole and 1.0g of dicyclohexyl carbodiimide are added, and the reaction is carried out for 1h, and then treated to obtain 24.5g of a negative photoresist.

[0085] S2, preparing a short channel electrode

[0086] A slit is opened on the edge of the fluorine crystal mica, and water is immersed along the slit, the water immersed in the slit will expand the fluorine crystal mica, and two pieces of cleaved fluorine crystal mica 1 are obtained;

[0087] The negative photoresist is spin-coated on the cleaved surface of the cleaved fluorine crystal mica 1, and then placed in a drying oven at a temperature of 80℃ for vacuum drying for 20min, after the curing is completed, the negative photoresist is exposed to light using a photoetching machine, the negative photoresist layer is soaked in a developing solution, a patterned photoresist surface is obtained, and an electron beam evaporation technology is used to deposit a silver layer on the patterned photoresist surface, to obtain a patterned electrode layer 2, then the photoresist is stripped to obtain the cleaved fluorine crystal mica 1 modified by the electrode layer 2;

[0088] The scanning tunneling microscope needle tip 3 is used to open a trench on the electrode layer 2, so that the electrode layer 2 has a gap to obtain a short channel electrode 4 to be transferred.

[0089] S3, preparing a short channel electrode

[0090] The cleaved fluorite mica 1 coated with the short channel electrode 4 after spin-coating 10wt% polyvinyl alcohol solution on the surface of the cleaved fluorite mica 1 is placed in a drying oven with a temperature of 80℃ for vacuum drying for 20min, to obtain the cleaved fluorite mica 1 with the surface attached with the adhesion layer 5;

[0091] A polyvinyl alcohol film with a thickness of 150μm is attached to a polydimethylsiloxane sheet with a thickness of 250μm to form a support layer 6, and the side of the support layer 6 with the flexible adhesive film is attached to the adhesion layer 5, and the material is transferred to a drying oven, the temperature of the drying oven is increased to 50℃, and the temperature is maintained for 10min, to obtain the cleaved fluorite mica 1 modified with the composite architecture layer;

[0092] The cleaved fluorite mica 1 modified with the composite architecture layer is soaked in deionized water for 12h, and then the surface moisture is blown dry, and then the composite architecture layer is peeled off from the cleaved fluorite mica 1, to obtain the composite architecture layer;

[0093] The side of the support layer 6 in the composite architecture layer is attached to a glass sheet, and the composite architecture layer is attached to a single crystal silicon 7 by using a transfer table, and in the attached state, a pressure of 200Pa is applied, and the attached interface is heated, the heating temperature is 140℃, and the temperature is maintained for 5min, to obtain a short channel transistor precursor;

[0094] After the support layer 6 is peeled off from the short channel transistor precursor, the material is soaked in a dissolving solution for 5min, the adhesion layer 5 is dissolved, and then the material is placed in a drying oven with a temperature of 50℃, and nitrogen is used as the atmosphere, and the material is dried to a constant weight, to obtain a short channel transistor.

[0095] Example 2

[0096] The present embodiment is used to provide a method for preparing a short channel transistor by using a hard needle tip, which comprises the following steps:

[0097] S1, preparing a negative photoresist

[0098] 13.4g of 3,3'-diaminobenzophenone, 8.6g of 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 38.3g of N,N-dimethylformamide and 1.0g of triethylamine are weighed according to the weight parts and added to a reaction kettle, stirred at room temperature for 4h, and then treated to obtain 21.2g of a negative photoresist precursor;

[0099] 20.0g of a photoresist precursor, 6.0g of 3-aminopropyltriethoxysilane and 90.0g of dimethyl sulfoxide are weighed according to the weight parts and added to a reaction kettle, stirred at room temperature for 10min, the temperature of the reaction kettle is lowered to 0℃, 1.6g of 1-hydroxybenzotriazole and 1.6g of dicyclohexyl carbodiimide are added thereto, and the temperature is maintained for 2h of reaction, and then treated to obtain a negative photoresist.

[0100] S2, preparing a short channel electrode

[0101] A slit is opened at the edge of the fluoromica, and water is immersed along the slit. The water immersed in the slit will expand the fluoromica, and two pieces of cleaved fluoromica 1 are obtained.

[0102] After the negative photoresist is spin-coated on the cleaved surface of the cleaved fluoromica 1, it is placed in a drying oven at a temperature of 80°C for vacuum drying for 40 min. After curing, the negative photoresist is exposed to radiation using a photoetching machine. The negative photoresist layer is soaked in a developing solution to obtain a patterned photoresist surface. The surface of the patterned photoresist is then deposited with a silver layer using electron beam evaporation technology. After the patterned electrode layer 2 is obtained, the photoresist is peeled off to obtain the cleaved fluoromica 1 modified with the electrode layer 2.

[0103] A trench is processed on the electrode layer 2 using a scanning tunneling microscope needle 3 to produce a gap in the electrode layer 2, obtaining a short-channel electrode 4 to be transferred.

[0104] S3, preparation of a short-channel electrode

[0105] After spin-coating a 15wt% polyvinyl alcohol aqueous solution on the surface of the cleaved fluoromica 1, the short-channel electrode 4 is coated. Then, it is placed in a drying oven at a temperature of 80°C for vacuum drying for 40 min, obtaining the cleaved fluoromica 1 with a surface-attached adhesive layer 5.

[0106] A polyvinyl alcohol film with a thickness of 100μm is attached to a polydimethylsiloxane sheet with a thickness of 200μm to form a support layer 6. The support layer 6 is attached to the adhesive layer 5 with the side of the flexible adhesive film. The material is transferred to a drying oven, and the temperature of the drying oven is increased to 50°C. After maintaining the temperature for 15 min, the cleaved fluoromica 1 modified with the composite architecture layer is obtained.

[0107] The cleaved fluoromica 1 modified with the composite architecture layer is soaked in deionized water for 24 h. Then, the surface moisture is blown dry, and the composite architecture layer is peeled off from the cleaved fluoromica 1, obtaining the composite architecture layer.

[0108] The side of the support layer 6 in the composite architecture layer is attached to a glass sheet. The composite architecture layer is attached to a single crystal silicon 7 using a transfer table. While applying a pressure of 300 Pa in the attached state, the attached interface is heated to a temperature of 150°C for 10 min, obtaining a short-channel transistor precursor.

[0109] After the support layer 6 is peeled off from the short-channel transistor precursor, the material is soaked in a dissolving solution for 10 min. After the adhesive layer 5 is dissolved, the material is placed in a drying oven at a temperature of 60°C in a nitrogen atmosphere. After drying to a constant weight, the short-channel transistor is obtained.

[0110] Example 3

[0111] The embodiment is used for providing a method for preparing a short channel transistor by using a hard needle tip, comprising the following steps:

[0112] S1, preparing a negative photoresist

[0113] 13.4 g of 3,3'-diaminobenzophenone, 8.6 g of 2,2-bis(3,4-dicarboxyphenyl) propane dianhydride, 38.3 g of N,N-dimethylformamide and 1.0 g of triethylamine are weighed by weight parts and added to a reaction kettle, stirred at room temperature for 3 h, and then treated to obtain 21.3 g of a negative photoresist precursor;

[0114] 21.0 g of a photoresist precursor, 6.0 g of 3-aminopropyl triethoxysilane and 85.0 g of dimethyl sulfoxide are weighed by weight parts and added to a reaction kettle, stirred at room temperature for 8 min, the temperature of the reaction kettle is lowered to 3℃, 1.2 g of 1-hydroxybenzotriazole and 1.2 g of dicyclohexyl carbodiimide are added thereto, and the reaction is kept for 2 h, and then treated to obtain a negative photoresist.

[0115] S2, preparing a short channel electrode

[0116] A slit is opened at the edge of the fluorine crystal mica, water is immersed along the slit, and the water immersed in the slit will expand the fluorine crystal mica to obtain two pieces of cleaved fluorine crystal mica 1;

[0117] The negative photoresist is spin-coated on the cleaved surface of the cleaved fluorine crystal mica 1, and then placed in a drying box at a temperature of 80℃ for vacuum drying for 30 min, after the solidification is completed, the negative photoresist is exposed to radiation by using a photoetching machine to obtain a patterned photoresist surface, and then the silver layer is deposited on the patterned photoresist surface by using an electron beam evaporation technology to obtain a patterned electrode layer 2, and then the photoresist is stripped to obtain the cleaved fluorine crystal mica 1 modified by the electrode layer 2;

[0118] The scanning tunneling microscope needle tip 3 is used to open a trench on the electrode layer 2 to make the electrode layer 2 have a gap to obtain a short channel electrode 4 to be transferred.

[0119] S3, preparing a short channel electrode

[0120] After the short channel electrode 4 is coated on the surface of the cleaved fluorine crystal mica 1, a 15wt% polyvinyl alcohol aqueous solution is spin-coated on the surface of the cleaved fluorine crystal mica 1, and then placed in a drying box at a temperature of 80℃ for vacuum drying for 30 min to obtain the cleaved fluorine crystal mica 1 with the adhesion layer 5 attached to the surface;

[0121] A 125-μm polyvinyl alcohol film was attached to a 225-μm polydimethylsiloxane sheet to form a support layer 6, the side of the support layer 6 to which the flexible adhesive film was attached was attached to the adhesive layer 5, and the material was transferred to a drying oven, the temperature of which was raised to 50°C, and the material was kept at this temperature for 12 min to obtain a cleaved fluorine crystal mica 1 modified with a composite framework layer;

[0122] The cleaved fluorine crystal mica 1 modified with a composite framework layer was immersed in deionized water for 18 h, and then the surface moisture was blown dry, and then the composite framework layer was peeled off from the cleaved fluorine crystal mica 1 to obtain a composite framework layer.

[0123] The side of the support layer 6 in the composite framework layer was attached to a glass sheet, and the composite framework layer was attached to a single crystal silicon 7 using a transfer table, and a pressure of 250 Pa was applied while the interface was heated to 145°C for 8 min to obtain a short channel transistor precursor.

[0124] After the support layer 6 was peeled off from the short channel transistor precursor, the material was immersed in a dissolving solution for 8 min, and then the material was placed in a drying oven at a temperature of 55°C under a nitrogen atmosphere until the material reached a constant weight to obtain a short channel transistor.

[0125] Comparative Example 1

[0126] The difference between this comparative example and Example 3 is that step S1 was omitted, and in step S2, a positive photoresist was used instead of a negative photoresist.

[0127] Comparative Example 2

[0128] The difference between this comparative example and Example 3 is that in step S2, a negative photoresist precursor glue was used instead of a negative photoresist.

[0129] Performance test:

[0130] The resolution of the electrode layer and the leveling ability and adhesion grade of the photoresist cured layer prepared in Examples 1-3 and Comparative Examples 1-2 were tested.

[0131] The resolution of the electrode layer was tested according to the standard GB / T 29556-2013 “Surface Chemical Analysis Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy Transverse Resolution, Analysis Area, and Sample Area Detectable by Analyzer Determination”.

[0132] The height difference of the photoresist after curing was determined according to the standard GB / T 33403-2016 “Test Method for Self-leveling Performance of Adhesives”.

[0133] The adhesion grade of the photoresist after curing was determined according to the standard GB / T 33049-2016 "Method for Determining Adhesion of Optical Film Coating for Polarizer", and the determination results are shown in Table 1.

[0134] Table 1 - Performance detection data table of each sample

[0135]

[0136] Data analysis:

[0137] Comparative analysis of the data in Table 1 above, the resolution of the electrode layer material prepared by the photoresist prepared by the application and the method for preparing a short channel transistor provided by the application using a hard needle tip reaches 750 nm, the height difference of the photoresist after leveling is 0.5 mm, and the adhesion grade reaches 0 level, all data are better than the comparative example, which shows that the negative photoresist precursor prepared by the application is modified by a series of silane coupling agents, the leveling performance and adhesion are significantly improved, the surface is flat and has good properties, the ultraviolet lithography is uniform and efficient, thereby improving the accuracy of the patterning, further improving the resolution of the electrode layer, while reducing the complexity of the method for preparing a short channel transistor, the accuracy of the short channel electrode structure is improved.

[0138] The above content is only an example and description of the structure of the application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the structure of the application or exceed the scope defined by the claims.

[0139] In the description of the present specification, the description of the terms "one embodiment", "example", "specific example" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0140] The preferred embodiments of the application disclosed above are only used to help explain the application. The preferred embodiments do not describe all the details and limit the application to the specific embodiments. Obviously, many modifications and changes can be made according to the content of the present specification. The present specification selects and describes these embodiments in order to better explain the principles and practical applications of the application, so that those skilled in the art can well understand and utilize the application. The application is limited by the claims and their entire scope and equivalents.

Claims

1. A method for fabricating a short channel transistor using a hard tip, comprising: The method comprises the following steps: S1, making an electrode layer (2) on the surface of a substrate layer (1), and performing trenching treatment on the electrode layer (2) by using a hard needle tip (3) to make the electrode layer (2) have gaps to obtain a short channel electrode (4) to be transferred; S2, arranging an adhesion layer (5) on the substrate layer (1) and the short channel electrode; S3, arranging a support layer (4) on the adhesion layer (3) to obtain a substrate layer (1) modified by a composite architecture layer composed of the short channel electrode (4) / adhesion layer (5) / support layer (6); S4, peeling the composite architecture from the substrate layer (1) to obtain the composite architecture; S5, transferring the composite architecture to a target carrier (7) to obtain a short channel electrode; S6, separating the adhesion layer (5) and the support layer (6) in the composite architecture, and performing post-processing to obtain a short channel electrode tube. In step S1, the operation of making the electrode layer (2) comprises the following steps: A1, after spin-coating a negative photoresist on the substrate layer (1), transferring the substrate layer (1) to a drying box with a temperature of 80 DEG C for vacuum drying to obtain a substrate layer (1) with the negative photoresist attached to the surface; A2, after using a photoetching machine to radiate and expose the negative photoresist, soaking the negative photoresist layer with a developing solution to obtain a patterned photoresist surface; A3, using an electron beam evaporation technology to perform surface deposition on the patterned photoresist surface, peeling off the photoresist after obtaining a patterned electrode layer (2) to obtain a substrate layer (1) modified by the electrode layer (2); The preparation method of the negative photoresist is as follows: taking 20-30 parts of a photoresist precursor, 5-10 parts of 3-aminopropyl triethoxysilane and 75-100 parts of dimethyl sulfoxide by weight, adding them into a reaction kettle, stirring for 5-10 min at room temperature, reducing the temperature of the reaction kettle to 0-5 DEG C, adding 1-2 parts of 1-hydroxybenzotriazole and 1-2 parts of dicyclohexyl carbodiimide into the reaction kettle, and performing heat preservation reaction for 1-2 h, and then performing post-processing to obtain the negative photoresist; The preparation method of the negative photoresist precursor is as follows: taking 20-30 parts of 3,3'-diamino benzophenone, 12-20 parts of 2,2-bis(3,4-dicarboxyphenyl) propane dianhydride, 75-100 parts of N,N-dimethylformamide and 1-3 parts of triethylamine by weight, adding them into a reaction kettle, stirring for 2-4 h at room temperature, and then performing post-processing to obtain the negative photoresist precursor.

2. The method of claim 1, wherein the hard tip is formed of a material having a hardness of at least 7 Mohs. In step S2, the method for arranging the adhesion layer (5) comprises the following steps: spin-coating an adhesion solution on the surface of the substrate layer (1), coating the substrate layer (1) and the short channel electrode (4), transferring the material to a drying box with a temperature of 80 DEG C for vacuum drying, and performing heat preservation for 20-40 min to obtain a substrate layer (1) with the adhesion layer (5) attached to the surface.

3. The method of claim 1, wherein the hard tip is formed of a material having a hardness of at least 7 Mohs. In step S3, the operation of arranging the support layer (4) comprises the following steps: B1, attaching a flexible adhesion film to a thin plate to form a support layer (6); B2, attaching the side of the support layer (6) with the flexible adhesion film to the adhesion layer (5), transferring the material to a drying box, increasing the temperature of the drying box to 50 DEG C, performing heat preservation for 10-15 min, and arranging the support layer (4) on the adhesion layer (5).

4. The method of claim 1, wherein the hard tip is formed of a material having a hardness of at least 7 Mohs. In step S4, the operation of peeling the composite architecture includes: placing the substrate layer (1) modified by the composite architecture layer into deionized water for 12-24h, taking out and blowing dry the surface moisture, then peeling the composite architecture layer from the substrate layer (1) to obtain the composite architecture layer.

5. The method of claim 1, wherein the hard tip is formed of a material selected from the group consisting of diamond, silicon carbide, and silicon nitride. In step S5, the operation of transferring the composite architecture includes the following steps: C1, one side of the support layer (6) in the composite architecture layer is attached to a glass sheet, and the composite architecture layer is attached to the target carrier (7) by using a transfer table; C2, while applying a pressure of 200-300Pa in the attached state, the attached interface is heated, the heating temperature is 140-150℃, and the heating is maintained for 5-10min to obtain a short channel electrode.

6. The method of claim 1, wherein the hard tip is formed of a material selected from the group consisting of diamond, silicon carbide, and silicon nitride. In step S6, the operation of separating the adhesion layer (5) and the support layer (6) in the composite architecture includes: soaking the short channel precursor into a dissolving solution for 5-10min, dissolving the adhesion layer (5), then collecting the support layer (6) for standby, to obtain a short channel transistor precursor.

7. The method of claim 1, wherein the hard tip is formed of a material selected from the group consisting of diamond, silicon carbide, and silicon nitride. In step S6, the post-processing operation includes: placing the material in a drying box with a temperature of 50-60℃, using nitrogen as the atmosphere, drying to a constant weight of the material, to obtain a short channel transistor.

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