Poly Si1-xGex films have been suggested as a promising alternative to the currently employed poly-Si gate electrode for CMOS technology due to lower resistivity, less boron penetration, and less gate depletion effect than those of poly Si gates. We investigated the formation of poly Si1-xGex films grown by UHV CVD using Si2H6 and GeH4 gases, and studied their microstructures as well as their electrical characteristics. The Ge content of the Si1-xGex films increased linearly with the flux of the GeH4 gas up to x=0.3, and saturated above x=0.45. The deposition rate of the poly Si1-xGex films increased linearly with the flux of the GeH4 gas up to x=0.1, above which it is slightly changed. The resistivity of the Si1-xGex films decreased as the Ge content increased, and was about one half of that of poly-Si films at the Ge content of 45%. The C-V measurements of the MOSCAP structures with poly Si1-xGex gates demonstrated that the flat band voltage of the poly Si1-xGex films was lower than that of poly-Si films by 0.2V.
|Journal||Materials Research Society Symposium - Proceedings|
|Publication status||Published - 2001 Jan 1|
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering