High-Mobility CVD-Grown Ge/Strained Ge0.9Sn0.1/Ge Quantum-Well pMOSFETs on Si by Optimizing Ge Cap Thickness
Journal
IEEE Transactions on Electron Devices
Journal Volume
64
Journal Issue
6
Pages
2498-2504
Date Issued
2017
Author(s)
Abstract
The high peak mobility of 509 cm2/ $\text {V}\cdot \text {s}$ of the chemical vapor deposition -grown GeSn pMOSFETs is obtained using 1-nm Ge cap. The Ge cap on GeSn can reduce the scattering of oxide/interface charges and surface roughness for the holes in the GeSn quantum wells. However, the thick cap induces holes in the Ge cap itself, leading lower mobility than GeSn channels. The on current is enhanced by external stress due to the effective mass reduction. The normalized noise power density of the GeSn devices decreases with increasing Ge cap thickness, indicating the carrier number fluctuation and correlated mobility fluctuation are suppressed when the holes are away from interface. ? 1963-2012 IEEE.
Subjects
Chemical vapor deposition; MOSFET devices; Semiconductor quantum wells; Surface roughness; Cap thickness; Carrier number fluctuation; Correlated mobility fluctuations; Effective mass; External stress; High mobility; Normalized noise; Peak mobility; Germanium
SDGs
Type
journal article