Low volatility solvent-based method for forming thin film nanoporous aerogels on semiconductor substrates
US6645878B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2002 |
| Grant date | Nov 11, 2003 |
| Priority date | — |
| Expiry date | Apr 30, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02282
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
This invention has enabled a new, simple thin film nanoporous dielectric fabrication method. In general, this invention uses glycerol, or another low volatility compound, as a solvent. This new method allows thin film aerogels/low density xerogels to be made without supercritical drying, freeze drying, or a surface modification step before drying. Thus, this invention allows production of nanoporous dielectrics at room temperature and atmospheric pressure, without a separate surface modification step. Although this new method allows fabrication of aerogels without substantial pore collapse during drying, there may be some permanent shrinkage during aging and/or drying. This invention allows controlled porosity thin film nanoporous aerogels to be deposited, gelled, aged, and dried without atmospheric controls. In another aspect, this invention allows controlled porosity thin film nanoporous aerogels to be deposited, gelled, rapidly aged at an elevated temperature, and dried with only passive atmospheric controls, such as limiting the volume of the aging chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.