Quantum wires in strained silicon quantum wells on tilted substrates

Abstract

Quantum wires have been fabricated in strained silicon heterostructures grown on 2∘tilted substrates. Magnetoresistance of both wires and Hall bars have been examined at 0.3 K for slow Shubnikov–de Haas (SdH) oscillations that would indicate the formation of minigaps in the band structure of off-axis electron transport. Structures were oriented both parallel and perpendicular to the step edges. The Hall bar structures exhibit no evidence of miniband formation at 0.3 K, and little anisotropy other than slightly reduced carrier density and mobility in the perpendicular Hall bar. The quantum wires are decidedly more modulated by low-frequency oscillations, and exhibit anisotropic behavior.