Solder resistance method for gold-plated layer on sintering surface of radio frequency module cavity

Abstract

The invention discloses a radio frequency module cavity sintering surface gold-plated layer resistance welding method, which comprises the following steps: carrying out local gold plating on a radio frequency module cavity to form a sintering surface; programming the carrier embedded in the square groove of the cavity to ensure that the engraving position of the laser engraving machine is close to the wall of the bottom of the embedded square groove so as to block the gold plating layer in the square groove; the carrier is installed on the plane of the cavity, programming is conducted, it is ensured that the size of the engraving position of a laser engraving machine is consistent with the size of the carrier, and a gold plating layer on the plane is blocked; and setting process parameters of a laser engraving machine, clamping the cavity, engraving the back surface and the front surface of the cavity, and completing the blocking of the gold-plated layer. According to the invention, the cleaning work of overflowing solder after the substrate is sintered can be greatly reduced, and the production efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radio frequency module cavity soldering resistance, and in particular to a method for soldering resistance of a gold-plated layer on a sintered surface of a radio frequency module cavity. Background Art

[0002] As RF microwave modules become increasingly complex and reliability requirements rise, module assembly involves the sintering and bonding of various microwave substrates and carriers. Because the sintered surface must meet solderability requirements, the RF microwave module cavity is typically partially gold-plated to ensure solderability. However, because the carrier mounting surface and the substrate mounting surface share the same gold-plated surface, solder can flow along the intact gold-plated surface during sintering of the microwave substrate into the carrier mounting position. This can cause solder contamination during installation and prevent the carrier from being positioned flat. This solder must be manually scraped off to remove the solder before bonding can be performed. Manual solder scraping is inefficient and difficult to achieve precise positioning. It can also easily scratch the gold plating around the carrier, which must be retained, affecting the reliable sintering of the substrate. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for solder resisting the gold-plated layer on the sintered surface of the cavity of an RF module. By adopting laser engraving technology, the gold-plated layer on the sintered surface of the cavity of the RF module is divided and blocked, so that a continuous and complete gold-plated surface is divided into several independent sintered surfaces according to different installation positions of the carrier, forming a discontinuous gold-plated surface, thereby blocking the solder from overflowing to the gold-plated layer at the carrier installation position when the substrate is sintered, ensuring that the carrier installation surface is clean and flat, and the subsequent carrier bonding process can be smoothly implemented.

[0004] The present invention is implemented by adopting the following technical solution: a method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity, comprising the following steps: Partially gold-plating the RF module cavity to form a sintered surface; For the carrier embedded in the square groove of the cavity, program it to ensure that the laser engraving machine engraving position is near the bottom wall of the embedded square groove to block the gold-plated layer in the square groove; When the carrier is installed on the cavity plane, program it to ensure that the engraving position size of the laser engraving machine is consistent with the size of the carrier to block the gold plating layer on the plane; Set the laser engraving machine process parameters, clamp the cavity, engrave the back and front of the cavity, and complete the gold plating layer blocking.

[0005] Furthermore, the sintered surface of the RF module cavity (including the installation position of the microstrip substrate and the carrier) is a complete and continuous gold-plated surface with good solderability. It is the installation and fixing surface for sintering and bonding the module cavity substrate and the carrier (including embedded installation and flat installation). It is a continuous and complete gold-plated surface without any divisions. The thickness of the gold plating layer is 0.5mm, with good solderability, ensuring the sintering and bonding of the substrate and the carrier; a microstrip substrate is provided on the sintered surface, and the microstrip substrate is physically connected and mechanically fixed to the RF module cavity through sintering, so that the microstrip substrate and the RF module cavity form a reliable connection. In addition to meeting the mechanical fixing strength, it must also meet the void ratio requirements to ensure reliable grounding and heat dissipation of the microwave substrate.

[0006] Furthermore, the carrier is a molybdenum-copper alloy. The molybdenum-copper alloy is physically connected and mechanically fixed to the cavity using a bonding process, so that the carrier and the cavity form a reliable connection. In addition to meeting the mechanical fixing strength, it is also necessary to meet the void ratio requirements to ensure reliable grounding and heat dissipation of the molybdenum-copper alloy. The carrier installation method includes an embedded installation method in the cavity square groove and a flat installation method on the cavity sintering surface. The carrier is physically connected and mechanically fixed to the cavity using a bonding process, so that the carrier and the cavity form a reliable connection. In addition to meeting the mechanical fixing strength, it is also necessary to meet the void ratio requirements to ensure reliable grounding and heat dissipation of the carrier.

[0007] Furthermore, the cavity is made of aluminum alloy 6061, and the sintered surface is partially gold-plated with a gold layer thickness of 1.27um. There is a microstrip substrate on the sintered surface that needs to be sintered and fixed to the cavity. The sintering process adopts a soft soldering process, and the solder is SAC305 with a melting point of 217°C. The microwave substrate is physically connected and mechanically fixed to the RF module cavity through sintering; there are a large number of carriers (including special-shaped carriers) on the sintered surface of the cavity that need to be fixed to the cavity by a bonding process. The carrier is a molybdenum-copper alloy, the surface is fully gold-plated, and the gold layer thickness is 2um.

[0008] Furthermore, for the carrier embedded in the square groove of the cavity, a laser engraving machine is used to engrave the bottom near the wall of the square groove to accurately block the gold-plated layer in the square groove.

[0009] Furthermore, for the installation of the carrier embedded in the square groove of the cavity, the specific method is: use a laser engraving machine to accurately program the gold layer solder mask position near the wall of the bottom of the square groove, and then etch the gold layer to form a local blockage. The etching position accuracy is ±0.05mm, ensuring that the gold-plated layer in the sintering area of ​​the microstrip substrate around the square groove is not damaged, ensuring that the microstrip substrate is reliably sintered without voids, and at the same time ensuring that the solder does not overflow into the area when the microstrip substrate is sintered in the square groove engraving area, keeping the area clean and free of solder contamination, and avoiding the carrier from being unevenly placed due to solder inflow and contamination during installation, affecting the installation of the carrier.

[0010] Furthermore, when the carrier is installed on the plane of the cavity, a laser engraving machine is used to engrave the plane where the carrier is installed, so as to accurately block the gold-plated layer on the plane.

[0011] Furthermore, for the installation of the carrier on the cavity plane, the specific method is: use a laser engraving machine to accurately program the gold layer solder mask position at the carrier installation plane position, and then etch the gold layer to form a local blockage. The etching position accuracy is ±0.05mm, ensuring that the gold-plated layer in the microstrip substrate sintering area around the plane engraving area is not damaged, ensuring that the microstrip substrate is reliably sintered without voids, and at the same time ensuring that the solder does not overflow into the area when the microstrip substrate in the plane engraving area is sintered, keeping the area clean and free of solder contamination, and avoiding the carrier from being unevenly placed due to solder inflow and contamination during installation, affecting the carrier installation.

[0012] The beneficial effects of the present invention are as follows: the present invention uses laser engraving to accurately divide the continuous gold-plated surface of the RF cavity sintering, so that the continuous gold-plated surface is divided into several independent gold-plated surfaces according to the needs of the carrier assembly position, thereby effectively blocking the solder from overflowing to the carrier installation position during the sintering of the microwave substrate, avoiding pollution and interference with the subsequent installation of the carrier. This method can greatly reduce the cleaning work of the overflowed solder after the substrate is sintered, and greatly improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0014] Figure 1 Flowchart of the present invention; Figure 2 This is the front view of the RF module cavity; Figure 3 This is the back view of the RF module cavity; Figure 4 To block the gold plating layer, laser engrave the front image; Figure 5 Laser engraving of the backside to block the gold plating. DETAILED DESCRIPTION

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0016] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0017] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0018] See also Figures 1 to 5 A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity comprises the following steps: Partially gold-plating the RF module cavity to form a sintered surface; For the carrier embedded in the square groove of the cavity, program it to ensure that the laser engraving machine engraving position is near the bottom wall of the embedded square groove to block the gold-plated layer in the square groove; When the carrier is installed on the cavity plane, program it to ensure that the engraving position size of the laser engraving machine is consistent with the size of the carrier to block the gold plating layer on the plane; Set the laser engraving machine process parameters, clamp the cavity, engrave the back and front of the cavity, and complete the gold plating layer blocking.

[0019] In this embodiment, the sintered surface of the RF module cavity (including the installation position of the microstrip substrate and the carrier) is a complete and continuous gold-plated surface with good solderability. It is the installation and fixing surface for sintering and bonding the module cavity substrate and the carrier (including embedded installation and flat installation). It is a continuous and complete gold-plated surface without any divisions. The thickness of the gold plating layer is 0.5 mm and has good solderability, ensuring the sintering and bonding of the substrate and the carrier.

[0020] The cavity is constructed of aluminum alloy 6061, with the sintered surface partially plated with gold (1.27µm thick). A microstrip substrate is sintered onto the sintered surface to secure it to the cavity. This process uses soft soldering, using SAC305 solder (melting point 217°C). Sintering physically and mechanically secures the microstrip substrate to the RF module cavity, ensuring a reliable connection between the two. In addition to meeting mechanical strength requirements, the required void ratio must also be met to ensure reliable grounding and heat dissipation. Numerous carriers (including those with unusual shapes) are bonded to the cavity's sintered surface. These carriers are made of a molybdenum-copper alloy and are fully plated with gold (2µm thick). Carrier mounting options include embedding within the cavity's square slots or mounting on the cavity's flat surface. Bonding ensures a reliable connection between the carriers and the cavity. In addition to meeting mechanical strength requirements, the required void ratio must also be met to ensure reliable grounding and heat dissipation.

[0021] In this embodiment, the carrier is embedded in the square groove of the cavity for installation. A laser engraving machine is used to accurately program the position of the gold layer solder mask near the wall at the bottom of the square groove, and then the gold layer is etched to form a local blockage. The etching position accuracy is ±0.05mm, and the etching parameters are: speed 2000ms / s, power 40%, and frequency 30Khz. This ensures that the gold-plated layer in the sintering area of ​​the microstrip substrate around the square groove is not damaged, and that the microstrip substrate is reliably sintered without voids. At the same time, it ensures that the solder does not overflow into the area when the microstrip substrate is sintered in the square groove engraving area, keeping the area clean and free of solder contamination, and avoiding the carrier from being unevenly placed due to solder inflow and contamination during installation, thereby affecting the installation of the carrier.

[0022] In this embodiment, the carrier cavity is sintered on a flat surface for installation. A laser engraving machine is used to precisely program the gold layer solder mask position at the carrier installation plane, and then the gold layer is etched to form a local blockage. The etching position accuracy is ±0.05mm, and the etching parameters are: speed 2000ms / s, power 40%, and frequency 30Khz. This ensures that the gold-plated layer in the microstrip substrate sintering area around the flat engraving area is not damaged, and that the microstrip substrate is reliably sintered without voids. At the same time, it ensures that the solder does not overflow into the area when the microstrip substrate in the flat engraving area is sintered, keeping the area clean and free of solder contamination, and avoiding uneven placement due to solder inflow and contamination during carrier installation, thereby affecting carrier installation.

[0023] The present invention uses laser engraving to accurately divide the continuous gold-plated surface of the RF cavity sintering, so that the continuous gold-plated surface can be divided into several independent gold-plated surfaces according to the needs of the carrier assembly position. This can effectively block the solder from overflowing to the carrier installation position during the microwave substrate sintering, avoiding pollution and interference with the subsequent installation of the carrier. This method can greatly reduce the cleaning work of the overflowed solder after the substrate is sintered, and greatly improve production efficiency.

[0024] For the sake of simplicity, the aforementioned embodiments are described as a series of actions. However, those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are preferred embodiments, and the actions involved are not necessarily required by this application.

[0025] The above embodiments describe the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Without departing from the spirit and scope of the present invention, modifications and variations made by those skilled in the art without departing from the spirit and scope of the present invention should be within the scope of protection of the appended claims.

Claims

1. A method for soldering gold-plated layer on the sintered surface of a radio frequency module cavity, characterized in that: The steps include: Partially gold-plating the RF module cavity to form a sintered surface; For the carrier embedded in the square groove of the cavity, program it to ensure that the laser engraving machine engraving position is near the bottom wall of the embedded square groove to block the gold-plated layer in the square groove; When the carrier is installed on the cavity plane, program it to ensure that the engraving position size of the laser engraving machine is consistent with the size of the carrier to block the gold plating layer on the plane; Set the laser engraving machine process parameters, clamp the cavity, engrave the back and front of the cavity, and complete the gold plating layer blocking.

2. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 1, characterized in that: The sintered surface is a complete and continuous gold-plated surface without any divisions, and the gold-plated surface is solderable.

3. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 1, characterized in that: A microstrip substrate is provided on the sintering surface. The microstrip substrate is physically connected and mechanically fixed to the RF module cavity through sintering, so that the microstrip substrate and the RF module cavity form a reliable connection. In addition to meeting the mechanical fixing strength, it must also meet the void ratio requirements to ensure reliable grounding and heat dissipation of the microwave substrate.

4. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 1, characterized in that: The carrier is a molybdenum-copper alloy, which is physically connected and mechanically fixed to the cavity by a bonding process, so that the carrier and the cavity form a reliable connection. In addition to meeting the mechanical fixing strength, it must also meet the void ratio requirements to ensure reliable grounding and heat dissipation of the molybdenum-copper alloy.

5. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 1, characterized in that: For the installation of the carrier embedded in the square groove of the cavity, a laser engraving machine is used to engrave the bottom near the wall of the square groove to accurately block the gold-plated layer in the square groove.

6. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 5, characterized in that: For the installation of the carrier embedded in the square groove of the cavity, the specific method is: use a laser engraving machine to accurately program the gold layer solder mask position near the wall of the bottom of the square groove, and then etch the gold layer to form a local blockage. The etching position accuracy is ±0.05mm to ensure that the gold-plated layer in the sintering area of ​​the microstrip substrate around the square groove is not damaged, and the microstrip substrate is reliably sintered without voids. At the same time, it is ensured that the solder does not overflow into the area when the microstrip substrate is sintered in the square groove engraving area, keeping the area clean and free of solder contamination, avoiding the carrier from being unevenly placed due to solder inflow and contamination during installation, which affects the installation of the carrier.

7. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 1, characterized in that: For carriers installed on the cavity plane, a laser engraving machine is used to engrave the plane where the carrier is installed to accurately block the gold-plated layer on the plane.

8. A method for soldering a gold-plated layer on a sintered surface of a radio frequency module cavity according to claim 7, characterized in that: For the installation of the carrier on the cavity plane, the specific method is: use a laser engraving machine to accurately program the gold layer solder mask position at the carrier installation plane, and then etch the gold layer to form a local blockage. The etching position accuracy is ±0.05mm. Ensure that the gold-plated layer in the microstrip substrate sintering area around the plane engraving area is not damaged, ensure that the microstrip substrate is reliably sintered without voids, and at the same time ensure that the solder does not overflow into the area when the microstrip substrate in the plane engraving area is sintered, keep the area clean and free of solder contamination, and avoid the carrier from being unevenly placed due to solder inflow and contamination during installation, which affects the installation of the carrier.

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