Electroplating mask process
By inkjet printing hot melt wax materials and combining UV curing and chemical etching treatment, the problems of high cost and complex process of traditional electroplating mask methods are solved, and the effect of precise control of the electroplating area and improving the electroplating quality is achieved.
Patent Information
- Application Number
- CN202510332769.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2025-06-06
AI Technical Summary
The traditional electroplating mask production method is costly, complex in process and cannot form irregular surfaces. The inkjet printing technology has not been fully utilized in electroplating mask production.
The hot-melting wax material is printed on the surface of the metal substrate by inkjet printing, and an electroplating mask is formed through UV curing treatment, and the substrate activity is improved in combination with chemical etching and electrochemical treatment, and the adhesion of the mask material and the electroplating layer is enhanced.
It realizes precise control of the electroplating area without using traditional masks, improves the plating quality, reduces costs, simplifies processes, reduces waste emissions, and is suitable for the production of various electronic components.
Smart Images
Figure CN120099599A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of electronic manufacturing, in particular to an electroplating mask process. Background Art
[0002] In the electronic manufacturing process, the preparation of electroplating mask is a key step. The electroplating mask process is a technology used to selectively protect certain areas from being electroplated during the electroplating process. By using mask materials, metal deposition can be prevented in specific areas, thereby achieving electroplating of complex patterns and fine structures. Traditional electroplating mask production methods, such as exposure and development or laser direct writing technology, have problems such as high cost, complex process or inability to form irregular surfaces. However, the use of inkjet printing technology to produce electroplating masks can significantly reduce costs and simplify the process.
[0003] The purpose of the present invention is to provide a process method for printing a hot melt wax material on a metal substrate surface by an inkjet printing process for electroplating. The method can accurately control the electroplating area and improve the electroplating quality without using a traditional mask, and has the advantages of low cost and simple operation. It is more environmentally friendly due to its lower energy consumption and less waste emissions. Summary of the invention
[0004] The object of the present invention is to provide an electroplating mask process to solve the problems raised in the above background technology.
[0005] To achieve the above object, the present invention provides the following technical solution: an electroplating mask process, the specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot melt wax material: Select paraffin with a melting point of 50-120°C as the printing material; Step 3, inkjet printing: Use inkjet printing equipment to print paraffin in a patterned manner on the metal substrate to be electroplated. The resolution of the inkjet printing equipment is 100-2400dpi and the printing speed is 0.1-2m / s; Step 4, curing: Select UV curing hot melt wax during the printing process. After printing, use a curing LED lamp with a wavelength of 10-450 nanometers and a curing energy of 100-3000mj / cm2 for curing; Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, the electroplating time is 1-35 minutes, and after the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by using a mask removal process, specifically, the copper substrate is placed in hot water at 20-90° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements.
[0006] Preferably, in the step three, the inkjet printing equipment optimizes the heating control to quickly heat the wax from room temperature to the melting point to become a liquid state. The heating temperature is between 60-130 degrees, and the temperature can be accurately maintained to allow the wax to circulate between the ink path and the nozzle in a flowing state with a flow rate of 0.1-100 ml / min, meeting the flow rate of various types of nozzles, accurately controlling the negative pressure to ensure the negative pressure required for maintaining the semi-meniscus of the nozzle, and controlling the pressure at -55-50±0.01 mbar. It supports multiple nozzles with a number of 1-128 nozzles, is suitable for a variety of substrate materials such as copper, stainless steel, and nickel, is suitable for a variety of basic sizes of 0.001-1m, supports sheet materials and continuous material strips, has an automatic nozzle maintenance function, has a non-stop production function, has mechanical positioning and visual positioning functions, and has a continuous AOI visual inspection function.
[0007] Preferably, the hot melt wax in step 4 is a phase change material, which is solid at room temperature and liquid after heating and melting, and is electroplated and patterned by an inkjet printer in the liquid state. The material is optimized through the formula, with a melting point between 50-120 degrees, an operating temperature between 60-130 degrees, a viscosity range of 5-50cps at the operating temperature, and excellent acid resistance. It has a barrier property for 0.1-99% concentration of HF, HNO3, HCl2, H2SO4 or mixed acids for 10 seconds to 2 hours. After adding the UV curing process, the working temperature of the electroplating solution is 10-90 degrees, and it is soluble in alkali solution.
[0008] Preferably, the UV curing lamp source in step 4 includes but is not limited to low / medium / high doped mercury lamps, ferrite lamps, halogen lamps, gallium lamps and LEDs, and the curing energy is 10-450nm wavelength.
[0009] Preferably, the print head of the inkjet printing device is processed by piezoelectric ceramics (PIEZO) or MEMS (micro-electromechanical system) production technology, the print head resolution is 100-2400dpi, the print head withstands a process temperature of 20-130 degrees, and the print head printing viscosity range is 5-200cps.
[0010] Preferably, the electroplating materials supported in this process include but are not limited to copper, nickel, gold, and silver; the supported substrates include but are not limited to rack plating, horizontal plating, and continuous plating.
[0011] Preferably, in step six, after the hot melt wax completes the electroplating process with alkali solution, it is removed from the printing substrate. The alkali solution includes but is not limited to a solution of potassium hydroxide or sodium hydroxide and water. The temperature of the alkali solution is 0-100 degrees, the concentration of the alkali solution is 0.1-45%, and the time for the hot melt wax to be completely dissolved in the alkali solution is 1-1000 seconds.
[0012] Compared with the prior art, the present invention has the following beneficial effects: 1) Reduce costs: Inkjet printing technology is used to make electroplating masks, which does not require expensive exposure and development or laser direct writing equipment, significantly reducing production costs. In addition, since inkjet printing uses print-on-demand (DoD) printing, there is no ink waste; this case uses non-curing or UV-curing phase change hot melt wax materials, which have no or little VOC emissions, save energy and have no impact on the environment; 2) Simplified process: The inkjet printing process is carried out at room temperature and pressure, without the need for high vacuum conditions. The process is simple and easy to control. In addition, the electroplating mask patterning process only requires an inkjet printer and UV curing equipment (depending on the hot melt wax material), which greatly simplifies the production process. 3) Improve material utilization: Inkjet printing technology can accurately control the printing volume and reduce material waste; 4) Environmentally friendly and efficient: The mask removal process provided can efficiently remove hot melt wax while reducing the impact on the environment; 5) Wide scope of application: This method is suitable for the production of various electronic components such as connectors and connectors, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 This is a flow chart of the process steps. DETAILED DESCRIPTION
[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0015] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0016] See also Figure 1 , the present invention provides a technical solution: An electroplating mask process, the specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot-melt wax material: Select paraffin with a melting point of 50-120°C as the printing material. Hot-melt wax material is a material with a low melting point, good fluidity and adhesion, usually including polyethylene wax, polypropylene wax, paraffin and other ingredients; the wax material can be quickly cooled and solidified after inkjet printing to form a protective film that can withstand the electroplating process; Step 3, inkjet printing: Use inkjet printing equipment to print paraffin wax in a patterned manner on the metal substrate to be electroplated. The resolution of the inkjet printing equipment is 100-2400dpi, and the printing speed is 0.1-2m / s. Use an inkjet printer to print the hot melt wax material onto the surface of the metal substrate according to the designed printing pattern. The wax material can select a suitable composition according to the type of substrate and the electroplating requirements to ensure that the specific area can be effectively protected from the erosion of the electroplating solution during the electroplating process. The inkjet printing process is carried out at room temperature and pressure, without high vacuum conditions, and the process is simple and the cost is low. The inkjet printer can use continuous inkjet or dot matrix inkjet technology. According to the shape, size and electroplating requirements of the metal substrate, set the appropriate printing resolution and printing speed. The inkjet amount of the wax material can be controlled by adjusting the working frequency, temperature and inkjet pressure of the nozzle; Step 4: Curing: Select UV curing hot melt wax during the printing process. After printing, use a curing LED lamp with a wavelength of 10-450 nanometers and a curing energy of 100-3000mj / cm2 for curing; Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, the electroplating time is 1-35 minutes, and after the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by using a mask removal process, specifically, the copper substrate is placed in hot water at 20-90° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Electroplating is performed on the surface treated substrate, and the electroplating solution can only contact the substrate in the area not covered by the hot-melt wax, so as to form a desired electroplating pattern on the substrate. After the electroplating is completed, a specific mask removal process is used to remove the hot-melt wax from the substrate. The present invention provides an efficient and environmentally friendly mask removal process, including pretreatment, hot water ultrasonic removal and alkaline solution immersion treatment steps, which can remove the hot-melt wax to the greatest extent and reduce the impact on the environment.
[0017] Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements.
[0018] In the step three, the inkjet printing device optimizes the heating control to quickly heat the wax from room temperature to the melting point to become a liquid state. The heating temperature is between 60-130 degrees, and the temperature can be accurately maintained to allow the wax to circulate between the ink path and the nozzle in a flowing state. The flow rate is 0.1-100 ml / min, which meets the flow rate of various types of nozzles. The negative pressure is accurately controlled to ensure that the negative pressure required for the nozzle meniscus is maintained. The pressure is controlled at -55-50±0.01 mbar. Multiple nozzles are supported, the number of nozzles is 1-128, and it is suitable for a variety of substrate materials such as copper, stainless steel, and nickel. It is suitable for a variety of basic sizes of 0.001-1m, supports sheet materials and continuous material strips, has automatic nozzle maintenance function, has non-stop production function, has mechanical positioning and visual positioning functions, and has continuous AOI visual inspection function.
[0019] The hot melt wax in step 4 is a phase change material, which is solid at room temperature and liquid after heating and melting, and is electroplated and patterned by an inkjet printer in the liquid state. The material is optimized through the formula, with a melting point between 50-120 degrees, an operating temperature between 60-130 degrees, a viscosity range of 5-50cps at the operating temperature, and excellent acid resistance. It has a barrier effect on 0.1-99% concentration of HF, HNO3, HCl2, H2SO4 or mixed acids for 10 seconds to 2 hours. After adding the UV curing process, the working temperature of the electroplating solution is 10-90 degrees and it is soluble in alkali solution.
[0020] The UV curing lamp source in step 4 includes but is not limited to low / medium / high doped mercury lamps, ferrite lamps, halogen lamps, gallium lamps and LEDs, and the curing energy is 10-450nm wavelength.
[0021] The print head of the inkjet printing device is processed by piezoelectric ceramics (PIEZO) or MEMS (micro-electromechanical system) production technology, the print head resolution is 100-2400dpi, the print head can withstand a process temperature of 20-130 degrees, and the print head printing viscosity range is 5-200cps.
[0022] The electroplating materials supported in this process include but are not limited to copper, nickel, gold, and silver; the supported substrates include but are not limited to rack plating, horizontal plating, and continuous plating.
[0023] In step six, after the hot melt wax completes the electroplating process with an alkali solution, it is removed from the printing substrate. The alkali solution includes but is not limited to a solution of potassium hydroxide or sodium hydroxide and water. The temperature of the alkali solution is 0-100 degrees, the concentration of the alkali solution is 0.1-45%, and the time it takes for the hot melt wax to be completely dissolved in the alkali solution is 1-1000 seconds.
[0024] Embodiment 1: The specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot melt wax material: Select paraffin with a melting point of 50°C as the printing material; Step 3, inkjet printing: using an inkjet printing device to print paraffin wax in a patterned manner on the metal substrate to be electroplated, the resolution of the inkjet printing device is 100 dpi, and the printing speed is 0.1 m / s; Step 4: Curing: Select UV curing hot melt wax during printing. After printing, use a curing LED lamp with a wavelength of 10 nanometers and a curing energy of 100mj / cm2 for curing. Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, the electroplating time is 1 minute, and after the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by using a mask removal process, specifically, the copper substrate is placed in hot water at 20° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements; Embodiment 2: The specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot melt wax material: Select paraffin with a melting point of 85°C as the printing material; Step 3, inkjet printing: using an inkjet printing device to print paraffin wax in a patterned manner on the metal substrate to be electroplated, the resolution of the inkjet printing device is 1250dpi, and the printing speed is 1.05m / s; Step 4: Curing: Select UV curing hot melt wax during printing. After printing, use a curing LED lamp with a wavelength of 230 nanometers and select a curing energy of 1550mj / cm2 for curing. Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, and the electroplating time is 18 minutes. After the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by a mask removal process, specifically, the copper substrate is placed in hot water at 55° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements; Embodiment three: The specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot melt wax material: Select paraffin with a melting point of 120°C as the printing material; Step 3, inkjet printing: using an inkjet printing device to print paraffin wax in a patterned manner on the metal substrate to be electroplated, the resolution of the inkjet printing device is 2400 dpi, and the printing speed is 2 m / s; Step 4: Curing: Select UV curing hot melt wax during printing. After printing, use a curing LED lamp with a wavelength of 450 nanometers and a curing energy of 3000mj / cm2 for curing. Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, and the electroplating time is 35 minutes. After the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by a mask removal process, specifically, the copper substrate is placed in hot water at 90° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements.
[0025] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.
[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. An electroplating mask process, characterized in that: The specific steps of the electroplating mask process are as follows: Step 1: Pretreatment: remove grease, dust, and oxide impurities on the surface of the substrate to ensure the effectiveness of subsequent steps, improve the activity of the substrate surface through chemical etching and electrochemical treatment, and enhance the adhesion of the mask material and the electroplating layer; Step 2: Prepare hot melt wax material: Select paraffin with a melting point of 50-120°C as the printing material; Step 3, inkjet printing: Use inkjet printing equipment to print paraffin in a patterned manner on the metal substrate to be electroplated. The resolution of the inkjet printing equipment is 100-2400dpi and the printing speed is 0.1-2m / s; Step 4, curing: Select UV curing hot melt wax during the printing process. After printing, use a curing LED lamp with a wavelength of 10-450 nanometers and a curing energy of 100-3000mj / cm2 for curing; Step 5, electroplating: electroplating is performed on the copper substrate after heat treatment, the electroplating solution is a nickel electroplating solution, the electroplating time is 1-35 minutes, and after the electroplating is completed, the desired nickel electroplating pattern is formed on the copper substrate; Step 6, mask removal: the paraffin is removed from the copper substrate by using a mask removal process, specifically, the copper substrate is placed in hot water at 20-90° C., and bubbling treatment is performed under the assistance of ultrasound, and the treated copper substrate is immersed in a mixed alkali solution containing but not limited to diethylene glycol monobutyl ether and potassium hydroxide to completely remove the residual paraffin; Step 7. Finished product inspection: Use inspection equipment to inspect the finished product after electroplating to confirm that its function and electroplating pattern meet the requirements.
2. The electroplating mask process according to claim 1, characterized in that: In the step three, the inkjet printing device optimizes the heating control to quickly heat the wax from room temperature to the melting point to become a liquid state. The heating temperature is between 60-130 degrees, and the temperature can be accurately maintained to allow the wax to circulate between the ink path and the nozzle in a flowing state. The flow rate is 0.1-100 ml / min, which meets the flow rate of various types of nozzles. The negative pressure is accurately controlled to ensure that the negative pressure required for the nozzle meniscus is maintained. The pressure is controlled at -55-50±0.01 mbar. Multiple nozzles are supported, the number of nozzles is 1-128, and it is suitable for a variety of substrate materials such as copper, stainless steel, and nickel. It is suitable for a variety of basic sizes of 0.001-1m, supports sheet materials and continuous material strips, has automatic nozzle maintenance function, has non-stop production function, has mechanical positioning and visual positioning functions, and has continuous AOI visual inspection function.
3. The electroplating mask process according to claim 1, characterized in that: The hot melt wax in step 4 is a phase change material, which is solid at room temperature and liquid after heating and melting, and is electroplated and patterned by an inkjet printer in the liquid state. The material is optimized through the formula, with a melting point between 50-120 degrees, an operating temperature between 60-130 degrees, a viscosity range of 5-50cps at the operating temperature, and excellent acid resistance. It has a barrier effect on 0.1-99% concentration of HF, HNO3, HCl2, H2SO4 or mixed acids for 10 seconds to 2 hours. After adding the UV curing process, the working temperature of the electroplating solution is 10-90 degrees and it is soluble in alkali solution.
4. The electroplating mask process according to claim 1, characterized in that: The UV curing lamp source in step 4 includes but is not limited to low / medium / high doped mercury lamps, ferrite lamps, halogen lamps, gallium lamps and LEDs, and the curing energy is 10-420nm wavelength.
5. The electroplating mask process according to claim 1, characterized in that: The print head of the inkjet printing device is processed by piezoelectric ceramics or MEMS production technology, the print head resolution is 100-2400dpi, the print head can withstand a process temperature of 20-130 degrees, and the print head printing viscosity range is 5-200cps.
6. The electroplating mask process according to claim 1, characterized in that: The electroplating materials supported in this process include but are not limited to copper, nickel, gold, and silver; the supported substrates include but are not limited to rack plating, horizontal plating, and continuous plating.
7. The electroplating mask process according to claim 1, characterized in that: In step six, after the hot melt wax completes the electroplating process with an alkali solution, it is removed from the printing substrate. The alkali solution includes but is not limited to a solution of potassium hydroxide or sodium hydroxide and water. The temperature of the alkali solution is 0-100 degrees, the concentration of the alkali solution is 0.1-45%, and the time it takes for the hot melt wax to be completely dissolved in the alkali solution is 1-1000 seconds.