Pre-sculpting of Si fin elements prior to cladding for transistor channel applications
US9653584B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 2013 |
| Grant date | May 16, 2017 |
| Priority date | — |
| Expiry date | Dec 23, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/00
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Transistor fin elements (e.g., fin or tri gate) may be modified by radio frequency (RF) plasma and/or thermal processing for purpose of dimensional sculpting. The etched, thinned fins may be formed by first forming wider single crystal fins, and after depositing trench oxide material between the wider fins, etching the wider fins using a second etch to form narrower single crystal fins having undamaged top and sidewalls for epitaxially growing active channel material. The second etch may remove a thickness of between a 1 nm and 15 nm of the top surfaces and the sidewalls of the wider fins. It may remove the thickness using (1) chlorine or fluorine based chemistry using low ion energy plasma processing, or (2) low temperature thermal processing that does not damage fins via energetic ion bombardment, oxidation or by leaving behind etch residue that could disrupt the epitaxial growth quality of the second material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.