Preparation method for nanowire

Abstract

The invention relates to the technical field of silicon carbide devices, and discloses a nanowire preparation method which comprises the following steps: preparing a substrate wafer (1); coating a photoresist material layer (2) on the surface of the substrate wafer (1); a growth hole (21) is formed in the photoresist material layer (2) through a laser direct writing photoetching method; putting the substrate wafer (1) into a chemical liquid containing metal ions, and growing a metal structure in the growth hole (21) through electroplating; and removing the photoresist material layer (2) by using a chemical method or a physical firing method to form the metal nanowire (3). According to the invention, the diameter of the metal nanowires and the distance between the metal nanowires can be accurately controlled, and the distribution of the metal nanowires can be arbitrarily designed; the surface area of a metal pad of the chip can be greatly increased, and the surface activation energy is improved, so that the temperature required by the chip in the subsequent welding process is greatly reduced, and meanwhile, the welding strength of chip packaging is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon carbide devices, and in particular to a method for preparing nanowires. Background Art

[0002] Currently, copper nanowires are produced using either current or thin-film techniques, both of which require complex machinery and specialized materials. These methods have the following drawbacks: 1. Quality varies significantly due to environmental influences, making it difficult to control; 2. As the coverage area increases, different areas exhibit varying properties, hindering diverse applications; 3. Reproducibility is poor, hindering stability for large-scale production; and 4. Due to the depth of focus limitations of traditional stepper lithography, exposure and development with a photoresist thickness exceeding 5 μm and an aspect ratio exceeding 10x is generally difficult.

[0003] The current patent number is CN201911090620.8, which discloses a packaging structure and manufacturing method of a silicon carbide MOSFET module. It discloses a wiring method of silicon carbide, which is relatively complex and costly. Summary of the Invention

[0004] The present invention addresses the shortcomings of the prior art and provides a method for preparing nanowires.

[0005] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0006] A method for preparing nanowires, comprising the steps of:

[0007] 1) Preparing a substrate wafer for growing metal nanowires;

[0008] 2) coating a layer of photosensitized photoresist material on the surface of the substrate wafer;

[0009] 3) forming a growth hole of a specific shape on the photoresist layer by laser direct writing lithography;

[0010] 4) placing the substrate wafer after step 3) into a chemical liquid containing metal ions of the metal to be grown (including but not limited to copper), and growing a metal structure in the growth hole by electroplating;

[0011] 5) The photoresist layer is removed by a chemical method or a physical burning method, and the metal structure in the growth hole of the photoresist layer is retained, thereby forming metal nanowires.

[0012] A method for preparing nanowires, comprising the steps of:

[0013] 1) Preparing a substrate wafer for growing metal nanowires;

[0014] 2) coating a layer of organic mask on the surface of the substrate wafer;

[0015] 3) Forming a growth hole of a specific shape on the organic mask by laser burning;

[0016] 4) placing the substrate wafer after step 3) into a chemical liquid containing metal ions of the metal to be grown (including but not limited to copper), and growing a metal structure in the growth hole by electroplating;

[0017] 5) The organic mask is removed by chemical methods or physical burning methods, and the metal structure in the growth holes of the organic mask is retained, thereby forming metal nanowires.

[0018] Preferably, a metal layer is provided on the surface of the substrate wafer in step ), and the metal layer is distributed according to design requirements; the metal layer is a copper metal layer.

[0019] Preferably, the photoresist material layer in step 2) is a photoresist layer, but is not limited to photoresist.

[0020] Preferably, the thickness of the photoresist material layer in step 2) is 3 to 50 microns.

[0021] Preferably, the organic mask in step 2) is a photoresist coating or a non-photosensitive organic coating with a thickness of 3 to 50 microns.

[0022] Preferably, the growth hole formed in step 3) has a diameter of 100 nanometers to 30,000 nanometers.

[0023] Preferably, in step 4), the treatment is carried out by a chemical method, wherein the temperature of the chemicals is between 10 degrees Celsius and 70 degrees Celsius, and the electroplating current is between 0.1 amperes and 30 amperes.

[0024] Preferably, in step 4), the growth length of the metal nanowires is 3 to 50 microns.

[0025] Preferably, the method for removing the photoresist layer 2 in step 5) includes dry stripping or wet stripping.

[0026] Due to the adoption of the above technical solutions, the present invention has significant technical effects: the present application can achieve precise positioning, and only needs to open holes on the metal surface of the substrate wafer, and no holes are required in other non-metallic areas; uniform distribution is achieved, and the nanowires in each area remain consistent; the method is simple, and only needs to adopt laser direct writing lithography or laser burning combined with electroplating to grow and obtain, which is suitable for large-scale production; at the same time, the diameter of the metal nanowires and the distance between the metal nanowires can be precisely controlled, and the distribution of the metal nanowires can be arbitrarily designed; the surface area of the chip metal pad can be greatly increased, and the surface activation energy can be improved, thereby greatly reducing the temperature required for the chip in the subsequent welding process, and at the same time greatly improving the welding strength of the chip package. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of step 1) of Example 1 of the present invention.

[0028] Figure 2 Schematic diagram of step 2) of Example 1 of the present invention.

[0029] Figure 3 Schematic diagram of step 3) of Example 1 of the present invention.

[0030] Figure 4 Schematic diagram of step 4) of Example 1 of the present invention.

[0031] Figure 5 Schematic diagram of step 5) of Example 1 of the present invention.

[0032] Figure 6 2) of Example 2 of the present invention.

[0033] The parts indicated by the numbers in the accompanying drawings are as follows: 1—substrate wafer, 2—photoresist material layer, 2′—organic mask, 21—growth hole, 3—metal nanowire. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0035] Example 1

[0036] A method for preparing nanowires, as shown in the figure, comprises the following steps:

[0037] 1) Preparing a substrate wafer 1 for growing metal nanowires;

[0038] 2) coating a photosensitive photoresist layer 2 on the surface of the substrate wafer 1;

[0039] 3) forming a growth hole 21 of a specific shape on the photoresist layer 2 by laser direct writing lithography;

[0040] 4) growing metal (including but not limited to copper) by electroplating, specifically by placing the substrate wafer 1 after step 3) in a chemical liquid containing metal ions (including but not limited to copper) of the metal to be grown, and growing a metal structure in the growth hole 21 by electroplating;

[0041] 5) The photoresist layer 2 is removed by a chemical method or a physical burning method, and the metal structure in the growth hole 21 of the photoresist layer 2 is retained, thereby forming the metal nanowire 3.

[0042] In step 1), a metal layer is provided on the surface of the substrate wafer 1, and the metal layer is distributed according to design requirements; the metal layer is a copper metal layer.

[0043] The growth hole 21 formed in step 3) has a diameter of 15000 nanometers.

[0044] In step 4), the treatment is carried out by a chemical method, wherein the temperature of the chemical is 40 degrees Celsius and the electroplating current is 15 amperes.

[0045] Step 4) The growth length of the metal nanowire 3 is 26 microns.

[0046] In step 5), the method for removing the photoresist layer 2 includes dry stripping or wet stripping.

[0047] Example 2

[0048] The same as Example 1, except for a method for preparing nanowires, as shown in the figure, the steps include:

[0049] 1) Preparing a substrate wafer 1 for growing metal nanowires;

[0050] 2) coating a layer of organic mask 2' on the surface of the substrate wafer 1;

[0051] 3) forming a growth hole 21 of a specific shape on the organic mask 2' by laser burning;

[0052] 4) growing metal (including but not limited to copper) by electroplating, specifically by placing the substrate wafer 1 after step 3) in a chemical liquid containing metal ions (including but not limited to copper) of the metal to be grown, and growing a metal structure in the growth hole 21 by electroplating;

[0053] 5) The organic mask 2 ′ is removed by a chemical method or a physical burning method, and the metal structure in the growth hole 21 of the organic mask 2 ′ is retained, thereby forming the metal nanowire 3 .

[0054] In step 1), a metal layer is provided on the surface of the substrate wafer 1, and the metal layer is distributed according to design requirements; the metal layer is a copper metal layer.

[0055] The growth hole 21 formed in step 3) has a diameter of 15000 nanometers.

[0056] In step 4), the treatment is carried out by a chemical method, wherein the temperature of the chemical is 40 degrees Celsius and the electroplating current is 5 amperes.

[0057] Step 4) The growth length of the metal nanowire 3 is 26 microns.

[0058] In step 5), the method for removing the photoresist layer 2 includes dry stripping or wet stripping.

[0059] Example 3

[0060] The same as embodiment 1, except that the photoresist material layer 2 in step 2) is a photoresist layer, but is not limited to photoresist.

[0061] The thickness of the photoresist layer 2 in step 2) is 26 microns.

[0062] Example 4

[0063] The same as Example 2, except that the organic mask 2' in step 2) is a photoresist coating or a non-photosensitive organic coating with a thickness of 26 microns.

[0064] In short, the above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the patent of the present invention.

Claims

1. A method for preparing nanowires, characterized in that: The steps include: 1) Preparing a substrate wafer (1) for growing metal nanowires; 2) coating a photosensitive photoresist material layer (2) on the surface of the substrate wafer (1); 3) forming a growth hole (21) on the photoresist material layer (2) by laser direct writing photolithography; 4) placing the substrate wafer (1) after step 3) into a chemical liquid containing metal ions, and growing a metal structure in the growth hole (21) by electroplating; 5) The photoresist material layer (2) is removed by a chemical method or a physical burning method, and the metal structure in the growth hole (21) of the photoresist material layer (2) is retained, thereby forming a metal nanowire (3).

2. A method for preparing nanowires, characterized in that: The steps include: 1) Preparing a substrate wafer (1) for growing metal nanowires; 2) coating a layer of organic mask (2') on the surface of the substrate wafer (1); 3) forming a growth hole (21) on the organic mask (2') by laser burning; 4) placing the substrate wafer (1) after step 3) into a chemical liquid containing metal ions, and growing a metal structure in the growth hole (21) by electroplating; 5) The organic mask (2') is removed by a chemical method or a physical burning method, and the metal structure in the growth hole (21) of the organic mask (2') is retained, thereby forming a metal nanowire (3).

3. The method for preparing nanowires according to any one of claims 1 or 2, characterized in that: In step 1), a metal layer is provided on the surface of the substrate wafer (1); the metal layer is a copper metal layer.

4. The method for preparing nanowires according to claim 1, wherein: The photoresist material layer (2) in step 2) is a photoresist layer.

5. The method for preparing nanowires according to claim 1, wherein: The thickness of the photoresist material layer (2) in step 2) is 3 to 50 microns.

6. The method for preparing nanowires according to claim 2, wherein: The organic mask (2') in step 2) is a photoresist coating or a non-photosensitive organic coating with a thickness of 3 to 50 microns.

7. The method for preparing nanowires according to any one of claims 1 or 2, characterized in that: The diameter of the growth hole (21) formed in step 3) is 100 nanometers to 30,000 nanometers.

8. The method for preparing nanowires according to any one of claims 1 or 2, characterized in that: In step 4), the treatment is carried out by a chemical method, wherein the temperature of the chemicals is between 10 degrees Celsius and 70 degrees Celsius, and the electroplating current is between 0.1 amperes and 30 amperes.

9. The method for preparing nanowires according to any one of claims 1 or 2, characterized in that: Step 4) The growth length of the metal nanowire (3) is 3 to 50 microns.

10. The method for preparing nanowires according to any one of claims 1 or 2, characterized in that: The method for removing the photoresist layer (2) in step 5) includes dry stripping or wet stripping.

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