Atomic-layer doping in Si by alternately supplied PH3 and SiH4 |
| |
Authors: | Y Shimamune M Sakuraba T Matsuura J Murota |
| |
Affiliation: | aLaboratory for Electronic Intelligent Systems, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan |
| |
Abstract: | Atomic-layer doping of P in Si epitaxial growth by alternately supplied PH3 and SiH4 was investigated using ultraclean low-pressure chemical vapor deposition. Three atomic layers of P adsorbed on Si(100) are formed by PH3 exposure at a partial pressure of 0.26 Pa at 450°C. By subsequent SiH4 exposure at 220 Pa at 450°C, Si is epitaxially grown on the P-adsorbed surface. Furthermore, by 12-cycles of exposure to PH3 at 300–450°C and SiH4 at 450°C followed by 20-nm thick capping Si deposition, the multi-layer P-doped epitaxial Si films of average P concentrations of 1021 cm−3 are formed. The resistivity of the film is as low as 2.4×10−4 Ω cm. By annealing the sample at 550°C and above, it is found that the resistivity increases and the surface may become rough, which may be due to formation of SiP precipitates at 550°C and above. These results suggest that the epitaxial growth of very low-resistive Si is achieved only at a very low-temperature such as 450°C. |
| |
Keywords: | Atomic-layer doping Epitaxial growth Chemical vapor deposition PH3 SiH4 |
本文献已被 ScienceDirect 等数据库收录! |
|