Inventors:
Gayle Miller - Colorado Springs CO, US
Eric Brown - Colorado Springs CO, US
Assignee:
Atmel Corporation - San Jose CA
International Classification:
H01L 21/473
US Classification:
438424, 257E21546, 257524
Abstract:
A method and resulting device that eliminates vertical steps or gaps in a deep trench isolation region and, thus, eliminates or drastically reduces a possibility of polysilicon stringers. Additionally, the invention allows an inexpensive dielectric material, for example a lower-quality silicon dioxide to be used to fill the deep trench and a higher quality oxide, in an electrically active region, to be used on an uppermost portion of the deep trench without affecting device performance or increasing a possibility of forming polysilicon stringers.