We studied the effects of growth pressure on Si1-xGex/Si heterostructures grown by rapid thermal chemical vapor deposition in the pressure range of 6-220 Torr. The material was characterized by photoluminescence (PL), x-ray reflectivity, and electrical measurements on resonant tunneling diodes (RTDs). High quality material was demonstrated throughout the pressure range, but a weaker PL intensity at higher pressure (220 Torr) indicates lower lifetimes. Interface abruptness was degraded at higher pressures due to gas transients. This was confirmed by x-ray reflectivity measurements and the performance of RTDs. We have established a low pressure limit to interface roughness of 0.2-0.5 nm, determined by x-ray reflectivity.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry
- Growth pressure effects
- rapid thermal chemical deposition