Chip glass packaging process

Abstract

The invention relates to a chip glass packaging process which comprises sputtering a glass film onto the surface of an exposed portion of a porcelain body in a thermistor chip to form a package. The chip glass packaging process of the present invention significantly enhances the mechanical strength, the moisture resistance and the corrosion resistance of the chip.

Description

technical field [0001] The invention relates to the technical field of electronic components, in particular to a chip glass packaging process. Background technique [0002] At present, there is no encapsulation protection for the exposed part of the ceramic body of the chips used for patching and inserting chips, such as thermistor chips. For example figure 1 As shown, the existing thermistor chip with upper and lower electrode structures includes a porcelain body 2 and electrodes 21 and 22 respectively arranged on the two surfaces of the porcelain body 2. The chip welding process connects the upper and lower electrodes before packaging, and the chip needs to be soaked in flux before inserting the chip. The flux contains acidic substances, and the acid will corrode the ceramic body 2 of the chip. After the ceramic body 2 is corroded, the resistance value of the chip will change. As a result, its performance also changes, resulting in a decrease in the reliability of the ch...

AI Technical Summary

Problems solved by technology

E.g figure 1 As shown, the existing thermistor chip with the upper and lower electrode structure includes a porcelain body 2 and electrodes 21 and 22 respectively arranged on the two surfaces of the porcelain body 2. The chip welding process connects the upper and lower electrodes before packaging, and the chip needs to be soaked in flux before inserting the chip. The flux contains acidic substances, and the acid will corrode the ceramic body 2 of the chip. After the ceramic body 2 is corroded, the resistance value of the chip will change. As a result, its performance also changes, resulting in a decrease in the reliability of the chip

another example figure 2 As shown, the existing thermistor chip with left and right electrode structures includes a porcelain body 20 and electrodes 201 located at both ends of the porcelain body 20. When in use, it is directly attached to the PCB board 60 printed with silver glue. The body 20 has no protection, and a water film will be formed on the surface of the chip in a humid environment to form a surface resistance, such as image 3 As shown, the change of the resistance value of the ceramic body 20 causes the chip performance to change accordingly. After testing, it is found that the thermistor chip with the resistance value of 10KΩ welded to the extension wire is placed in a constant humidity cabinet with a humidity of 90% for 1 hour. After the measurement, its resistance value became 9.980KΩ, indicating that the reliability of the chip decreased in a humid environment

[0003] In addition, the SMD chip and the circuit board are easily bent and deformed by external forces during the assembly process

For example, the thermistor chip will produce micro-cracks along with the deformation of the PCB board 60, resulting in abnormal performance or fracture and directly open circuit, such as Figure 4 As shown, especially when the PCB board and chip are injected in the injection molding process, the extrusion of the PCB board when the injection molding machine is clamping the upper and lower molds will cause micro-cracks or breakage in the ceramic body of the chip, resulting in defective chips (approximately 2% bad), after dismantling the packaging colloid on the bad chip, the resistance test of the chip is often found that the chip is close to an open circuit, and then soldered with an electric soldering iron, the chip is disconnected from the middle

[0004] It can be seen that the existing chip for chip placement and chip insertion has the problems of poor moisture resistance and low mechanical strength

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