The preset tin cover plate/shell is fixed on the alloy or ceramic shell after precise positioning and spot welding of the pre-formed tin solder sheet. The prefabricated tin shell solves the localization problem in the traditional process and shortens the packaging process. It is widely used in the airtight packaging of semiconductor devices. Features and advantages are as follows: accurate control of solder volume; Precise preforming of welding sheet; Simplify packaging process; High air tightness, high corrosion resistance and high reliability. Currently, jinxi plate/shell has been widely used in the hybrid integrated circuit, semiconductor integrated circuit, filter, microwave device, high power devices, connectors, sensors, photoelectric device of metal shell or ceramic shell airtight packaging and other special electronic components such as metal shell or ceramic shell airtight packaging and other fields.