Charge carrier transport in barrier in-macroporous silicon structures

Abstract

Charge carrier transport mechanism in barrier In-macroporous structures has been investigated. Currentvoltage, capacitance-voltage, photoelectrical and noise characteristics were analyzed comparatively in structures of macroporous and single-crystal silicon. There has been designed manufacture technology of ohmic and barrier contacts on 2D macroporous silicon as well as single-crystal silicon in the same technological cycle. The contacts were found to exhibit stable characteristics during six month period of time. The saturation of the reverse current at 0.2 ≤ U ≤ 1.0 V was observed at high temperatures. The carrier transport mechanism in the investigated structures are determined by thermal activation mechanisms at room temperature and tunneling of carriers through the transient region at temperatures T ≤ 180 K. Capacitance-voltage characteristics are similar to those observed in the metal-oxide-semiconductor structures and are included capacitance of the oxide layer and the depletion region. The presence of the transient region between metal and silicon was confirmed by the photoresponse spectra of Inmacroporous Si structures contained two pronounced peaks at the wavelengths 0.56 and 1.1 μm. The longwavelength peak was observed for In contacts on single n-Si crystal prepared by the same method.