First structural and electrical data are reported for SiGe/Si quantum well structures grown by a new ultra clean low temperature epitaxial deposition process at atmospheric pressure. It is found that the process suppresses the segregation of germanium, possibly by a chemical termination of the surface during the growth. Mutiple-quantum-well structures with controllable well widths and abrupt interfaces have been prepared at temperatures ranging from 550 to 650°C. Magneto-transport measurements of modulation doped quantum wells reveal hole mobilities of 2000 cm2/Vs at 4.2 K at a carrier density of 1.7*1012 cm-2 and a germanium concentration of 18% in the SiGe channel. Resonant tunneling diodes grown by this technique exhibit well resolved regions of negative differential resistance within a very symmetric I-V characteristic.
- SiGe quantum wells
- resonant tunneling diodes
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry