关键词: 气密性封装, 平行缝焊, 盐雾腐蚀, 盖板, 微观组织

Abstract: Parallel seam welding is a kind of hermetic package with low thermal stress and high reliability. It is one of the most frequently-used air-tight packaging methods for microelectronic devices. Electronic components used in some special environmental conditions need to be airtight sealed by parallel seam welding technology to prevent the circuit in the device from air tightness failure due to corrosion of the atmosphere. In this paper, the mechanism of salt spray corrosion failure of parallel welded package rear cover was systematically investigated from the microscopic perspective by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), metallographic analysis, and crystal analysis. The results show that the fundamental reason, why electrochemical corrosion occurs in air tight parallel seam welding under the environment of salt and spray, exists in that the surface coating changes from amorphous state to crystalline state and loses its amorphous protective film and the coating, which develops cracks. Hence, it has a certain guiding value and significance to analysis and give birth to a solution, which can provide a theoretical basis to improve the packaging quality of products in production.

Key words: Keywords:hermetic packaging, parallel seam welding, salt spray corrosion, cover, microstructure