Abstract: Electronic devices protected by an organic polymeric encapsulant and placed in a corrosive environment can have added protection by dispersing in the encapsulant particles of a solid buffer which tend to neutralize the effect of the corrosive agent. This approach is quite effective when strong acids are the corrosive agents, and when solid acid-base buffers are dispersed in the polymeric material. The encapsulant may be elastomeric, and silicone elastomers containing solid acid-base buffers are quite effective in protecting the underlying electronic device from corrosion by strong acids.

Abstract: In a semiconductor device encapsulation assembly (50; 60), a semiconductor device (21), preferably a pressure transducer, is mounted on a base (11) in a cavity (20) formed by the base and surrounding walls (15). Electrical connections, preferably wire bonds (27), connect the semiconductor device to conductor paths (28) on the base within the cavity. An encapsulation material comprising a thixotropic fluorosiloxane material (51; 61) is applied in the cavity and completely covers the semiconductor device and the electrical connections. This structure enables the semiconductor device to withstand typical automotive contaminants, such as mild acids and gasoline, while also preventing erratic semiconductor device operation due to bubbles which may be drawn into the encapsulation material.