Patent ID: 7564108
Filing Date: 2009-07-21
Classification: H01L

Abstract:
1. A gate dielectric for use in a transistor comprising: a high-k dielectric layer having a thickness from about 5 to 50 Å, the high-k dielectric layer comprising nitrogen interspersed throughout the high-k dielectric layer; and an underlying dielectric layer having a thickness from about 15 to 80 Å, the underlying dielectric layer having a nitrogen-containing first portion in contact with the high-k dielectric layer, and a substantially nitrogen-free second portion in contact with an underlying substrate, the nitrogen-free second portion comprising a first material and the nitrogen-containing first portion comprising the first material and nitrogen, the nitrogen-containing first portion having a steadily decreasing concentration of nitrogen from the high-k dielectric layer to the nitrogen-free second portion.