Analysis of water vapor control and passive layer process effecting on transistor performance and aluminum corrosion

Bipolar junction transistors can be used as switch transistors in satellite power system. In order to confirm that weather water vapor control and passive layer process effecting on transistor performance and Aluminum corrosion, 88 silicon NPN switching transistors with different process used in this paper. Experiments with temperature cycling and power on, the contrastive groups of which were with water vapor controlling and passive layer protecting, were completed. Analysis of the corrosion mechanism of Aluminum in the selected transistor elucidated effects of temperature, humidity (water vapor), voltage and ion contamination on occurrence, extent and speed of aluminum corrosion. By analyzing morphology, distribution and related factors of aluminum corrosion, a method for controlling aluminum corrosion by controlling water vapor inside transistor was put forward.