Improved retention of phosphorus donors in germanium using a non-amorphizing fluorine co-implantation technique
Abstract
Co-doping with fluorine is a potentially promising method for defect passivation to increase the donor electrical activation in highly doped n-type germanium. However, regular high dose donor-fluorine co-implants, followed by conventional thermal treatment of the germanium, typically result in a dramatic loss of the fluorine, as a result of the extremely large diffusivity at elevated temperatures, partly mediated by the solid phase epitaxial regrowth. To circumvent this problem, we propose and experimentally demonstrate two non-amorphizing co-implantation methods; one involving consecutive, low dose fluorine implants, intertwined with rapid thermal annealing and the second, involving heating of the target wafer during implantation. Our study confirms that the fluorine solubility in germanium is defect-mediated and we reveal the extent to which both of these strategies can be effective in retaining large fractions of both the implanted fluorine and, critically, phosphorus donors.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2017
- Source ID
- 10.1063/1.4999210
Entities
People
- Anu Agarwal
- Christopher Heidelberger
- Corentin Monmeyran
- David Pastor
- E. Napolitani
- Eric Mazur
- Hemi H. Gandhi
- Iain F Crowe
- Jürgen Michel
- Lionel C. Kimerling
- Russell Gwilliam
Organizations
- Air Force Office of Scientific Research
- Defense Threat Reduction Agency
- Harvard University
- Massachusetts Institute of Technology
- United States Department of Defense
- University of Manchester
- University of Padua
- University of Surrey