Method for actively sealing sapphire sheet and metal

Abstract

The invention provides a method for actively sealing a sapphire sheet and metal. The method is low in welding temperature, high in efficiency, good in reliability and low in cost. According to the method, high-temperature metallization is not required, expensive vacuum coating equipment and precious metal targets are also not required, the defects of long intermediate treatment process and time consumption are overcome, the total welding time is shortened, and the production efficiency is improved; the defect that flatness with high precise size and demanding requirement is required to be machined when welding sheets are adopted is avoided, and active titanium, zirconium, copper and nickel welding flux is directly adopted; the thickness of the wall of the sealing part of a metal piece is small, so that the thermal stress effect caused by the reaction of extrusion to the metal piece by the thermal expansion of the sapphire sheet during welding is reduced, and the probability of explosion of the sapphire sheet is reduced; meanwhile, welding can be accomplished at one step when the vacuum atmosphere temperature is lower than 1000 DEG C, the requirement on welding equipment is low, the product welding reliability and the yield are high, the air impermeability is good when baking is performed at the high temperature of 560 DEG C for 36 hours, and the requirement on the air impermeability of ultrahigh frequency electron tubes can be guaranteed.

Description

technical field [0001] The invention belongs to the technical field of vacuum device sealing, and in particular relates to an active sealing method for a sapphire sheet and a metal. Background technique [0002] In recent years, with the deepening of research on short millimeter wave electric vacuum devices, especially terahertz electric vacuum devices, the demand for sealing dielectric materials with low loss and high mechanical strength has been increasing. Among the current sealing media, compared with diamond, beryllium oxide, and boron nitride, sapphire has high mechanical strength, good microwave permeability, and low loss. It can be processed into ultra-thin thickness, mature manufacturing process, low cost, and non-toxic. Harmless, it has basically become the material of choice for the output window medium in the UHF electric vacuum device manufacturing industry. However, since sapphire is a high-purity alumina structure with few internal glass phases, metallization...

AI Technical Summary

Problems solved by technology

However, due to the current production process problems, the particle size of titanium-zirconium-copper-nickel active solder is obviously not as fine as that of silver-copper-titanium active solder, and the affinity with gemstones is not enough.

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