A method of inkjet patterning

Abstract

The application discloses a kind of methods for ink-jet patterning, the present application can realize the GAP value (a value) from 0-1mm adjustable controllable by this process, it is controlled according to the mode of DPI to depart from conventional ink-jet printing, i.e. the line width of metal deposition is controllable, and the morphology of metal deposition layer can be controlled, the morphology of metal deposition layer is as vertical as possible, the viscosity selection window of dam material is very large (1-10 million mP.s selectable), higher height-width ratio can be realized, the morphology is more steep, and at the same time, the dam material can be completed, the filled material only needs filling effect, covers the inside area of dam, without considering edge linearity and morphology, the requirement of material characteristics is reduced, by this process, as long as the thickness of metal layer and dam thickness are consistent, the inside of dam only needs to be filled and spread, ink material can be saved, by this method, the printing difficulty of filling area is greatly reduced, and the selection requirement of nozzle can be greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of inkjet printing application technology, mainly for patterning in the photovoltaic, semiconductor and display fields, and particularly to a method for inkjet patterning. Background Technology

[0002] Inkjet printing of metal patterns has attracted increasing attention from manufacturers due to its features that silicon-based microelectronic products do not possess, such as large area, flexibility and low cost. Currently, in the photovoltaic and semiconductor fields, the main patterning processes are photolithography, screen printing and inkjet printing. Compared with inkjet printing technology, screen printing has shortcomings.

[0003] (1) The material utilization rate is relatively low and the cost is high;

[0004] (2) In the process of industrialization, high-precision screen printing plates are expensive and have a short service life;

[0005] (3) Screen printing is a contact patterning method for materials, which can easily damage the substrate;

[0006] Furthermore, photolithography has drawbacks such as complicated procedures, expensive equipment, and high operational requirements.

[0007] Using inkjet printing technology for patterning not only reduces material waste, but the non-contact method is also more suitable for thinner substrates. Furthermore, it allows for different widths to be achieved according to customer requirements, eliminating the need for custom photomasks and screen printing plates. Only graphic editing and design are required. However, compared to conventional inkjet printing technology, which prints directly onto the substrate for patterning, it has the following disadvantages.

[0008] (1) The viscosity of the printed material is relatively low. After printing, the ink droplets spread outward, resulting in a wavy shape at the edge and poor straightness at the edge. Moreover, it can only be suppressed, not completely eliminated.

[0009] (2) When the line spacing is small, there is a risk of ink overflow causing sticking, and the line width at the edge cannot be well controlled;

[0010] (3) The morphology of the edge is uncontrollable. The edge is relatively gentle and not steep, which leads to the uncontrollable morphology of the subsequent metal layer deposition.

[0011] (4) Conventional inkjet printing line width can only be controlled by DPI. DPI can only be an integer, and it is impossible to achieve a specific integer line width.

[0012] Therefore, the present invention proposes a method for inkjet patterning. Summary of the Invention

[0013] The technical problem to be solved by this invention is to provide a method for inkjet patterning. This process enables adjustable and controllable GAP (a-value) from 0-1mm, departing from the conventional inkjet printing method of DPI control. This means the linewidth of the metal deposition is controllable, and the morphology of the metal deposition layer is also controllable, with the morphology of the metal deposition layer as vertical as possible. The viscosity selection window for the damming material is very large (10,000-100,000 mP.s selectable), allowing for higher aspect ratios and steeper morphologies. Furthermore, after the damming material is completed, the filling material only needs to fill and cover the internal area of ​​the dam, without needing to consider edge linearity and morphology. This reduces the requirements for material properties. With this process, as long as the thickness of the metal layer and the thickness of the dam are consistent, the internal area of ​​the dam only needs to be filled, saving ink material. This method significantly reduces the printing difficulty of the filled area and greatly reduces the requirements for printhead selection.

[0014] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is to provide an inkjet patterning method, the method comprising the following processes;

[0015] S1. Using high-precision printing technology on a silicon wafer substrate, first print a narrow linewidth (value b) first sacrificial layer dam as a barrier to isolate the printed filling area from the non-printed area. The sacrificial layer material must be solid at room temperature and can be cured after the ink droplets fall to achieve a large aspect ratio.

[0016] S2. The spacing between the dam frames is the GAP (value a) requirement value, which is the linewidth of the metal layer deposition.

[0017] S3. Then, the second sacrificial layer material is filled inside the dam frame by inkjet printing. The filling material is the same type of material as the dam material, or it can be different. It just needs to be inkjet printable and can be etched by the same type of cleaning solution as the first sacrificial layer.

[0018] S4. After cleaning, proceed to the next step of metal layer deposition. Deposition methods include: vapor phase deposition, electrochemical deposition, etc. to obtain the metal deposition layer.

[0019] S5. Finally, the sacrificial layers of the dam and the filling area are removed by etching with a cleaning solution.

[0020] The present invention is further configured such that: the sacrificial layer material of the dam is selected as follows: the sacrificial material is required to be solid at room temperature and can be cleaned by alkaline solution or ether solvent, including one or more of paraffin wax, stearic acid, palmitic acid, myristic acid and cinnamic acid.

[0021] The above technical solutions enable workers to better utilize existing materials during operation, thus improving ease of use.

[0022] The present invention is further configured such that: the inkjet sacrificial layer material is selected as follows: the sacrificial material is required to be solid at room temperature and can be cleaned by alkaline solution or ether solvent, including one or more of paraffin, stearic acid, palmitic acid, myristic acid and cinnamic acid.

[0023] The above technical solution facilitates the selection of inkjet sacrificial layer materials, allowing for the use of one or more of paraffin, stearic acid, palmitic acid, myristic acid, and cinnamic acid according to operational requirements.

[0024] The present invention is further configured such that the cleaning solution is selected from one or more of the following: KOH alkaline solution, NaOH alkaline solution, ammonia water, tetramethylammonium hydroxide solution, diethylene glycol butyl ether, ethylene glycol butyl ether, propylene glycol methyl ether acetate, diethylene glycol methyl ether acetate, and dipropylene glycol methyl ether acetate.

[0025] The above technical solution allows workers to use one or more of the following for cleaning operations: KOH alkaline solution, NaOH alkaline solution, ammonia water, tetramethylammonium hydroxide solution, diethylene glycol butyl ether, ethylene glycol butyl ether, propylene glycol methyl ether acetate, diethylene glycol methyl ether acetate, and dipropylene glycol methyl ether acetate, thereby improving the flexibility and efficiency of cleaning.

[0026] The beneficial effects of this invention are as follows:

[0027] 1. The present invention proposes an inkjet patterning method, through which the GAP value (a value) can be adjusted and controlled from 0-1mm, which is different from the conventional inkjet printing method of controlling by DPI, that is, the line width of metal deposition is controllable;

[0028] 2. The inkjet patterning method proposed in this invention enables controllable morphology of the metal deposition layer, making the morphology of the metal deposition layer as vertical as possible. The viscosity selection window of the damming material is very large (10,000-100,000 mP.s can be selected), which can achieve a higher aspect ratio and a steeper morphology.

[0029] 3. The inkjet patterning method proposed in this invention enables the filling material to cover the internal area of ​​the dam after the dam material is completed, without having to consider edge linearity and morphology, thus reducing the requirements for material properties.

[0030] 4. The inkjet patterning method proposed in this invention only requires ensuring that the thickness of the metal layer and the thickness of the dam are consistent. The interior of the dam only needs to be filled, which can save ink material.

[0031] 5. The inkjet patterning method proposed in this invention greatly reduces the difficulty of printing filled areas and significantly lowers the requirements for printhead selection. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of existing conventional inkjet printing methods;

[0033] Figure 2 This is a schematic diagram of an inkjet patterning method according to the present invention.

[0034] Figure 3 The table below shows the data for embodiments and comparative examples of this invention. Detailed Implementation

[0035] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0036] A method for inkjet patterning, the method comprising the following processes;

[0037] S1. Using high-precision printing technology on a silicon wafer substrate, a first sacrificial layer dam with a narrow linewidth (value b) is first printed as a barrier to isolate the printed filling area from the non-printed area. The sacrificial layer material must be solid at room temperature so that it can solidify after the ink droplets fall, achieving a large aspect ratio. The sacrificial material selection requirements are: the sacrificial material must be solid at room temperature and can be cleaned by alkaline solutions or ether solvents, including one or more of paraffin wax, stearic acid, palmitic acid, myristic acid, and cinnamic acid, so that workers can better use the available materials during operation and improve the convenience of use.

[0038] S2. The spacing between the dam frames is the GAP (value a) requirement value, which is the linewidth of the metal layer deposition.

[0039] S3. Then, the second sacrificial layer material is filled inside the dam frame by inkjet printing. The filling material is the same type of material as the dam material, or it can be different, as long as it can be inkjet printed. It can be etched by the same type of cleaning solution as the first sacrificial layer. The selection of inkjet sacrificial layer material: The sacrificial material is required to be solid at room temperature and can be cleaned by alkaline solution or ether solvent, including one or more of paraffin, stearic acid, palmitic acid, myristic acid, and cinnamic acid. This facilitates the selection of inkjet sacrificial layer material and allows for the use of one or more of paraffin, stearic acid, palmitic acid, myristic acid, and cinnamic acid according to the requirements of the operation.

[0040] S4. After cleaning, proceed to the next step of metal layer deposition. Deposition methods include: vapor phase deposition, electrochemical deposition, etc. to obtain the metal deposition layer.

[0041] S5. Finally, the sacrificial layers of the dam and the filling area are removed by etching with a cleaning solution. The cleaning solution can be selected from one or more of the following: KOH alkaline solution, NaOH alkaline solution, ammonia water, tetramethylammonium hydroxide solution, diethylene glycol butyl ether, ethylene glycol butyl ether, propylene glycol methyl ether acetate, diethylene glycol methyl ether acetate, and dipropylene glycol methyl ether acetate. This allows the staff to use one or more of these solutions during the cleaning operation, improving the flexibility and efficiency of the cleaning process.

[0042] When using this invention:

[0043] First, a dam sacrificial layer is printed on the substrate using printing technology. The linewidth is a fixed value b. The spacing a between the dam sacrificial layers is a blank area. Inkjet printing filler material is used inside the dam to obtain an intermediate product. Then, a metal layer is deposited to obtain a product with a metal layer. After cleaning and etching, the final product is obtained, and the linewidth of the metal layer is tested.

[0044] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for inkjet patterning, characterized in that: The method includes the following processes; S1. Using high-precision printing technology on a silicon wafer substrate, first print a narrow-line width first sacrificial layer dam, with the narrow line width value being b, as a barrier to isolate the printed filling area from the non-printed area. The material of the first sacrificial layer dam must be solid at room temperature and can be cured after the ink droplets fall, achieving a large aspect ratio. S2. The spacing between the first sacrificial layer dikes is the GAP requirement value, and the GAP value is a, which is the linewidth of the metal layer deposition. S3. Then, the second sacrificial layer material is filled into the first sacrificial layer dam by inkjet printing. The filling material is the same type of material as the first sacrificial layer dam material and can be etched by the same type of cleaning solution as the first sacrificial layer dam. S4. After cleaning, proceed to the next step of metal layer deposition. The deposition methods include: vapor phase deposition and electrochemical deposition to obtain the metal deposition layer. S5. Finally, the first sacrificial dam and the second sacrificial layer are removed by etching with a cleaning solution.

2. The inkjet patterning method according to claim 1, characterized in that: Selection of materials for the first sacrificial layer dam: The sacrificial material is required to be solid at room temperature and can be cleaned by alkaline solutions or ether solvents, including one or more of paraffin wax, stearic acid, palmitic acid, myristic acid, and cinnamic acid.

3. The inkjet patterning method according to claim 1, characterized in that: Selection of the second sacrificial layer material: The sacrificial material is required to be solid at room temperature and can be cleaned by alkaline solutions or ether solvents, including one or more of paraffin, stearic acid, palmitic acid, myristic acid, and cinnamic acid.

4. The inkjet patterning method according to claim 1, characterized in that: The cleaning solution is selected from one or more of the following: KOH alkaline solution, NaOH alkaline solution, ammonia water, tetramethylammonium hydroxide solution, diethylene glycol butyl ether, ethylene glycol butyl ether, propylene glycol methyl ether acetate, diethylene glycol methyl ether acetate, and dipropylene glycol methyl ether acetate.

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