P-i-n junction in silicon nanowires

P-i-n junctions were fabricated along silicon nanowires of about 8 nm in cross-sectional dimension via the conventional top-down approach. Rectifying electrical characteristics have been observed and the ideality factor is estimated to be 3.8, attributed to trapped charges in the encapsulating silicon dioxide layer. Dopants diffusion along the nanowires reduces the effective length of the intrinsic region. The reverse bias breakdown exhibiting a negative temperature coefficient could be attributed to tunneling effect. The p-i-n junctions respond well to illumination despite their small capture area and preliminary results on photoresponse will be presented.