Epitaxial growth of N delta doped Si films on Si(1 0 0) by alternately supplied NH ₃ and SiH ₄

Atomic-layer doping of N in Si epitaxial growth by alternately supplied NH ₃ and SiH ₄ was investigated using an ultra-clean low-pressure chemical vapor deposition (LPCVD). Atomic layer order nitrided Si(1 0 0) with N amount of 3 × 10 ¹⁴ cm ^-2 are formed by NH ₃ exposure at 500 Pa and 400°C. By subsequent SiH ₄ exposure at 25 Pa and 500°C, Si is epitaxially grown on the nitrided Si(1 0 0) with N amount of 3 × 10 ¹⁴ cm ^-2 . High quality epitaxial growth of the multi-layer N-doped Si film composed of the N layers of 3 × 10 ¹⁴ cm ^-2 and the 3.0 nm Si spacer is achieved. On the other hand, in case of 0.5 nm Si spacer, the crystallinity of N-doped Si film is degraded by the increase of N atoms with Si ₃ N ₄ structure after the second nitridation.