학술논문
The Radiation Tolerance of Strained Si/SiGe n-MODFETs
Document Type
Periodical
Author
Source
IEEE Transactions on Nuclear Science IEEE Trans. Nucl. Sci. Nuclear Science, IEEE Transactions on. 54(6):2251-2256 Dec, 2007
Subject
Language
ISSN
0018-9499
1558-1578
1558-1578
Abstract
The radiation tolerance of strained Si/SiGe n-MODFETs is investigated, using 10 keV X-rays, 63 MeV high energy protons, and 4 MeV low energy protons. The effects of radiation exposure on two major device design parameters (${\rm L}_{\rm SD}$ and ${\rm L}_{\rm G}$) in T-gate Si/SiGe n-MODFETs devices are examined. A strong dependence on source-drain spacing is observed for both the DC and RF characteristics. A drift-diffusion TCAD framework is used for 2-D device simulations. We believe that the low energy protons damage the SiGe/strained-Si/SiGe lattice, leading to partial strain relaxation. The conduction band-offset (CBO) of the strained SiGe/Si heterojunction is lowered leading to higher gate current leakage. The presence of radiation-induced bulk traps in the unrelaxed SiGe layers on the device behavior is also investigated.