Structure for protecting air bridges on semiconductor chips from damage

摘要

A protective cap is deposited over the top and sides of an air bridge structure located on an integrated circuit chip. The protective cap provides mechanical strength during the application of a high density interconnect structure over the chips, to prevent deformation of the sensitive (air bridge) structure, and also to prevent any contamination from intruding under the air bridge. More importantly, the protective cap does not impede the performance of the air bridge and therefore does not need to be removed, thereby eliminating the necessity of ablating the HDI structure. Furthermore, the protective cap allows additional area for metallization to provide alternate circuits for coupling, power or ground planes, etc.