Electrical properties of 2H-Si microwire grown by mixed-source hydride vapor phase epitaxy

Abstract

Hexagonal 2H polytypes of Si (2H-Si) exhibit promising mechanical and optical properties owing to their crystal structures with quasi-direct bandgap characteristics. However, few studies have investigated the electrical properties of 2H-Si semiconductors. In this study, we used a hot-probe measurement to determine the doping type of 2H-Si microwires (MWs) prepared by hydride vapor-phase epitaxy (HVPE). It was found that the 2H-Si MWs had unintentional n-type characteristics. For the first time, a heterojunction PN diode with n-type 2H-Si MW and p-type Si (100) was fabricated. According to the current–voltage and capacitance–voltage measurements, the n-type doping concentration of the unintentionally doped 2H-Si MWs was 4.3–9.5 × 1015 cm−3 and the electron mobility was 260–580 cm2/V·s.