Patent ID: 8987094
Filing Date: 2015-03-24
Classification: H01L

Abstract:
1. A method for fabricating a fin field effect transistor (FinFET) integrated circuit comprising: providing a crystalline substrate, where the substrate comprises a depth; forming an etch mask overlying the substrate; etching the substrate to form a plurality of fins having fin sidewalls, a fin top surface, and a fin height less than the substrate depth such that a trough is defined between adjacent fins, and where the trough comprises a trough base between fin sidewalls; depositing a first dielectric on the trough base, the fin sidewalls, and the etch mask positioned on the fin top surface; removing the first dielectric from the trough base such that the substrate is exposed at the trough base; crystallizing a trough filler from the exposed crystalline substrate at the trough base; oxidizing the trough filler to form a second dielectric within the trough such that a protruding fin portion extends above a second dielectric top surface; removing the first dielectric material and the etch mask from the protruding fin portion; and incorporating the protruding fin portions into the FinFET integrated circuit.