Band-tail profiling in microcrystalline silicon by photoconductivity analysis

Abstract

On the influence of short and medium range order on the material band gap in hydrogenated amorphous silicon

Study of anomalous behavior of steady state photoconductivity in highly crystallized undoped microcrystalline Si films

“…Several numerical and experimental observations of the temperature and intensity dependence of steady state photoconductivity (SSPC) have been used to explain the physics of gap states over a wide range in the bandgap of a-Si:H [9], whereas SSPC on lc-Si:H films has not been explored much [8,10]. We have studied the opto-electronic properties of well characterized lc-Si:H films having varying degree of crystallinity by employing steady state photoconductivity measurements and tried to identify the role of microstructure in determining the electrical transport.…”

“…This requires a complete effective density of state (DOS) profile of the heterogeneous lc-Si:H material. Some attempts have been made to decipher partial DOS distributions in the vicinity of conduction band (CB) edge [5][6][7][8] using a variety of probes.…”

Recombination traffic in highly crystallized undoped microcrystalline Si films studied by steady state photoconductivity

“…Another major hurdle in understanding the carrier transport of Ac-Si:H system is the non-availability of complete density of state (DOS) map. However, attempts were made to obtain the partial DOS distributions in the vicinity of conduction band (CB) edge using varieties of probes [6][7][8][9].…”

Photogating effect as a defect probe in hydrogenated nanocrystalline silicon solar cells

“…The assumption of these features is justified by various results in the literature. [17][18][19] We thus assume a mobility band gap with exponential band tails at the band edges and defects located between the band edges with distributions that can be described by Gaussians. We use a band gap value of 1.2 eV to describe both the intrinsic and doped nc-Si:H and vary the mobilities in a wide range to study their effect on PG, and later we fix the electron and hole mobilities to be 40 cm 2 / Vs and 4 cm 2 / Vs, respectively, for intrinsic ncSi:H. Properties of the doped layers and of the ITO and ZnO layers were also assumed to be homogeneous.…”