Impact of Si growth rate on coherent electron transport in Si:P delta-doped devices

Abstract

We address the impact of Si growth rate on electron transport in Si:P δ-doped devices encapsulated by low temperature Si molecular beam epitaxy. Si growth rates ranging from 0.05 to 2.2 Å s−1 were used in conjunction with 250 °C Si overgrowth. Using a combination of scanning tunneling microscopy and 4.2 K magnetotransport measurements, we find that high growth rates tend to degrade the crystal quality of the Si cap layer resulting in shorter electron mean free path and phase coherence length in such devices.