New polyimide for multi-chip module application

P-terphenyltetracarboxylic dianhydride (p-TPDA), which has a rodlike structure, has been developed as a raw material for polyimides in order to reduce the propagation delay time associated with polyimide packaging for multichip modules. The coefficient of thermal expansion (CTE) of the polyimides derived from p-TPDA is approximately 2*10/sup -6/. This is much lower than that of conventional polyimides derived from bisphenyltetracarboxylic dianhydride (BPDA), which have a CTE of 8*10/sup -6/ K/sup -1/. Another attribute that these polyimides have is low dielectric constant, with a typical value of about 2.9. As a result, this polyimide can give improved performance when used in multichip module applications.<
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