Selective nonconformal deposition for forming low dielectric insulation between certain conductive lines
US6048802A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 1997 |
| Grant date | Apr 11, 2000 |
| Priority date | — |
| Expiry date | Aug 5, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming low dielectric insulation between those pairs of conductive lines, of a level of interconnection for integrated circuits, having a gap of about 0.5 microns or less by depositing a nonconformal source with a poor step function for the insulating material, such as silane (SiH.sub.4) as the silicon (Si) source for silicon dioxide (SiO.sub.2), so as to create, in the gap, a large void whose dielectric constant is slightly greater than 1. After all of the conductive lines have received a deposit of conformal insulating material and a flowable insulating material, the composite insulating materials are removed, preferably by etching, from those pairs of conductive lines with a gap of about 0.5 microns or less. Now, a nonconformal insulating material with a poor step function is deposited and creates a large void in the open gaps of 0.5 microns or less. After creating the void, the deposition continues and is planarized at the desired composite thickness of insulation. Alternatively, a thin conformal insulating layer is first deposited as a liner on the conductive lines. The resulting structure of the interconnection level comprises a layer of insulation between and on…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.