Atomically Controlled Processing of Group IV Semiconductors for Ultralarge Scale Integration
- 28 Nov 2012 14:00
- PGI-Hörsaal, Geb. 04.8, Eingang E2, 2. OG, Raum 365
Prof. Junichi Murota
Research Institute of Electrical Communication, Tohoku University,
2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
The concept of atomically controlled processing is based on surface reaction control in Si-based CVD epitaxial growth. By the Si epitaxial growth over the material already-formed on Si(100), N, B and C atoms are confined within of about 1 nm thick layer, which is nearly the same as the measurement accuracy. In the P atomic-layer doping, segregation of P atoms during the Si epitaxial growth is suppressed by using Si2H6 instead of SiH4 at low temperature of 450 oC. Heavy C atomic-layer doping suppresses strain relaxation as well as intermixing between Si and Ge at the nm-order thick Si1-xGex/Si heterointerface. By the atomic-layer doping, higher carrier concentration and higher carrier mobility are achieved compared with continuous doping. It is confirmed that growth characteristics as well as electrical activity of impurity in the strained layer are influenced by the substrate surface strain. These results open the way to atomically controlled technology in ULSIs.