Patent ID: 7094659
Filing Date: 2006-08-22
Classification: H01L

Abstract:
1. A method of forming trench capacitor comprising the steps of: providing a silicon substrate having a deep trench and a pad structure, wherein a buried plate is formed in the silicon substrate adjacent to the trench; forming a collar dielectric layer conformably on a top surface and a sidewall of the pad structure and a upper sidewall of the trench; forming a high dielectric constant (high k) dielectric layer conformably covering the collar dielectric layer and extending to a bottom and a lower sidewall of the trench as a capacitor dielectric layer; filling a conductive layer into the trench, and recessing the conductive layer to a predetermined depth to act as a top electrode; and removing a portion of the high k dielectric layer and a portion of the collar dielectric layer on the sidewall of the trench using the conductive layer as a mask, wherein the collar dielectric layer is formed using self-starved atomic layer chemical vapor deposition (self-starved ALCVD).