Selective deposition of amorphous silicon film seeded in a chlorine gas and a hydride gas ambient when forming a stacked capacitor with HSG
US6146967A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1997 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Aug 20, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/964
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A polysilicon film is formed with enhanced selectivity by flowing chlorine during the formation of the film. The chlorine acts as an etchant to insulative areas adjacent polysilicon structures on which the film is desired to be formed. Bottom electrodes for capacitors are formed using this process, followed by an anneal to create hemishperical grain (HSG) polysilicon. Multilayer capacitor containers are formed in a non-oxidizing ambient so that no oxide is formed between the layers. The structure formed is planarized to form separate containers made from doped and undoped amorphous silicon layers. Selected ones of undoped layers are seeded in a chlorine containing environment and annealed to form HSG. A dielectric layer and second electrode are formed to complete the cell capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.