Patent ID: 7169681

Claim:
A method of forming a semiconductor device, the method comprising: preparing a semiconductor substrate having first and second regions defined thereon; forming a first trench in the first region and a second trench in the second region; forming a first dielectric layer on the first and second regions of the semiconductor substrate to conformally cover inside surfaces of the first and second trenches, wherein a thickness of the first dielectric layer is substantially the same on the inside surfaces of the first trench as it is on a surface of the semiconductor substrate in the first region; removing the first dielectric layer from the second region but leaving a portion of the first dielectric layer substantially on the first region; and forming a second dielectric layer having a dielectric constant higher than that of the first dielectric layer, on both the first and second regions, to conformally cover the inside surfaces of the first and second trenches, wherein a thickness of the second dielectric layer is substantially the same on the inside surfaces of the first and second trenches as it is on the surface of the semiconductor substrate in the first region and a surface of the semiconductor substrate in the second region.