Inventors:
Kyle P. Hunt - Richardson TX, US
Leila Elvira Noriega - Forney TX, US
Billy Alan Wofford - Dallas TX, US
Asadd M. Hosein - Plano TX, US
Binghua Hu - Plano TX, US
Xinfen Chen - Plano TX, US
Assignee:
Texas Instruments Incorporated - Dallas TX
International Classification:
H01L 21/302
H01L 21/3105
US Classification:
438692, 438300, 438633, 438689, 438697, 438734, 438733, 438722, 438723, 438724, 257500, 257501, 257506, 257E21214, 257E21218, 257E21243, 257E21244, 257E21245, 257E21246, 257E21303, 257E21304, 257E21311, 257E29261
Abstract:
A method for semiconductor processing is provided wherein a workpiece having an underlying body and a plurality of features extending therefrom, is provided. A first set of the plurality of features extend from the underlying body to a first plane, and a second set of the plurality features extend from the underlying body to a second plane. A protection layer overlies each of the plurality of features and an isolation layer overlies the underlying body and protection layer, wherein the isolation has a non-uniform first oxide density associated therewith. The isolation layer anisotropically etched based on a predetermined pattern, and then isotropically etched, wherein a second oxide density of the isolation layer is substantially uniform across the workpiece. The predetermined pattern is based, at least in part, on a desired oxide density, a location and extension of the plurality of features to the first and second planes.