Patent ID: 7101814
Filing Date: 2006-09-05
Classification: H01L

Abstract:
1. A method for forming a semiconductor device, comprising: forming a semiconductor wafer substrate assembly comprising a plurality transistors at a first density in an array region and a plurality of transistors at a second density in a periphery region, wherein the density of transistors in the array region is at least twice the density of transistors in the periphery region; and flowing a nonconformal oxide layer over the periphery and over the array at a uniform rate, wherein, during the flowing, the nonconformal oxide layer at least partially migrates from the periphery region to the array region to result in the nonconformal oxide layer having a first thickness over the plurality of transistors in the array and a second thickness over the plurality of transistors in the periphery, wherein subsequent to the formation and prior to an etch of the nonconformal oxide layer, the first thickness is greater than the second thickness.