HDP-CVD method for spacer formation
US6133151A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 10, 1999 |
| Grant date | Oct 17, 2000 |
| Priority date | — |
| Expiry date | May 10, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76897
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a self-aligned contact structure is disclosed based on an HDP-CVD (High-Density Plasma-Chemical Vapor Deposition) process. Initially, after a polysilicon layer and a metal layer are deposited and patterned on a wafer to fabricate a gate stack, an HDP-CVD process is employed to form a deposition layer to cover the patterned layers and wafer. A building of sharp ridges occurs over the gate stack. Next, a spacer deposition layer is then conformally deposited to cover the HDP-CVD deposition layer. An anisotropically etch process is then performed to etch the spacer deposition layer, wherein at least portions of the spacer deposition layer still covers top of the gate stack. Another anisotropically etch process is then performed to form the required contacts on the wafer. Because the HDP-CVD deposition layer on the gate structure is thick enough to protect the gate stack from etching, it is unnecessary to form the cap layer as conventionally.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.