Patent ID: 8319299

Claim:
A composite comprising a semiconductor material supported by a passivating layer, the passivating layer supported by a substrate, the substrate, comprising: a) a polyimide in an amount from 40 to 95 weight percent of the layer, the polyimide being derived from: i) at least one aromatic dianhydride, at least 85 mole percent of said aromatic dianhydride being a rigid rod type dianhydride, and ii)at least one aromatic diamine, at least 85 mole percent of said aromatic diamine being a rigid rod type diamine; and b) a filler that: a) is less than 800 nanometers in at least one dimension; b) has an aspect ratio greater than 3:1; c) is less than the thickness of the film in all dimensions; and d) is present in an amount from 5 to 60 weight percent of the total weight of the film, the substrate having a thickness from 8 to 150 microns.