Method for forming multi-level contacts using a H-containing fluorocarbon chemistry
US6080662A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 1998 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Nov 4, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31116
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming multi-level contact holes in a semiconductor structure is disclosed. The semiconductor structure includes a dielectric layer overlying a silicon substrate, a silicon nitride layer within the dielectric layer, the silicon nitride layer overlying a first conductive layer, a silicon oxynitride layer within the dielectric layer, the silicon oxynitride layer overlying a second conductive layer, and a plate poly layer. The method comprises: using a first etching step to etch through the dielectric layer to reach the silicon nitride layer as well as reach the silicon oxynitride layer, the first etching step using a combination of a first gas mixture and a first gas, the first gas mixture comprising a combination of N.sub.2, CO and Ar. The first gas includes C.sub.4 F.sub.8, CH.sub.3 F and O.sub.2, the flow rate ratio of the first gas C.sub.4 F.sub.8 /CH.sub.3 F/O.sub.2 is about 6:1:3. The flow rate of each component of the first gas mixture is that, the flow rate of N.sub.2 is about 0-20 sccm, the flow rate of CO is about 0-200 sccm, and the flow rate of Ar is about 100-600 sccm. In addition, the flow rate of each component of the first gas is that, the flow rate of C…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.