De-ionized water/ozone rinse post-hydrofluoric processing for the prevention of silicic acid residue
US5803980A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 1996 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | Oct 4, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31111
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
One embodiment of the instant invention is a method of preventing the formation of silicic acid on exposed silicon of an electronic device formed on a silicon wafer and having silicon features, the method comprising: removing a portion of oxide (step 302) formed on the silicon wafer thereby exposing at least some portion of the silicon substrate or the silicon features; cleaning the silicon wafer by subjecting the silicon wafer to an ozonated solution (step 304), preferably deionized water; and drying the silicon wafer (step 306). Preferably, a thin oxide is formed on the silicon wafer during the step of subjecting the wafer to the ozonated solution. The thin oxide is, preferably, on the order of approximately 6 to 20 .ANG. thick. After removing said portions of oxide and thereby exposing portions of said silicon wafer and/or silicon feature, the exposed silicon becomes hydrophobic. However, after the exposed silicon is subjected to the ozonated solution, the silicon wafer becomes hydrophilic--thereby preventing the formation of silicic acid on the silicon wafer or the silicon features.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.