A semiconductor device and method having a low-permittivity material between closely-spaced leads in order to decrease unwanted capacitance, while having a more structurally strong dielectric between widely-spaced leads where capacitance is not as critical. A metal layer 14 is deposited on a substrate...http://www.google.ca/patents/US5789319?utm_source=gb-gplus-sharePatent US5789319 - Method of dual masking for selective gap fill of submicron interconnects
