Reversible conductivity changes in discharge-produced amorphous Si

Abstract

A new reversible photoelectronic effect is reported for amorphous Si produced by glow discharge of SiH4. Long exposure to light decreases both the photoconductivity and the dark conductivity, the latter by nearly four orders of magnitude. Annealing above 150 °C reverses the process. A model involving optically induced changes in gap states is proposed. The results have strong implications for both the physical nature of the material and for its applications in thin-film solar cells, as well as the reproducibility of measurements on discharge-produced Si.

Nonlinear optical interactions in silicon waveguides

“…As a result, the nonlinear index reduces over time, while simultaneously increased linear losses are observed [33]. The material degradation of a-Si:H is a known phenomenon in the photovoltaic community and still not fully understood [41][42][43]. In another experiment, we have pumped the waveguides with photon energies well below the half-bandgap of our a-Si:H layers.…”

Progress in single junction microcrystalline silicon solar cells deposited by Hot-Wire CVD

“…This kind of material has a significant amount of amorphous tissue which can turn out to enhance the degradation of the device when exposed to long time illumination due to the so-called StaeblerWronski effect [22] (SWE). The recombination properties of µc-Si:H are attributed to recombination in the dangling bond defects present in the amorphous phase among the crystallites.…”

Voltage-dependent quantum efficiency measurements of amorphous silicon multi-junction mini-modules

“…In the case of amorphous silicon (a-Si) devices, they could also reduce the impact of Staebler-Wronski degradation [2]. However, the characterization of multi-junction solar cells presents additional challenges over that of single junctions [3] and their indoor current-voltage (I-V) calibration is affected by greater uncertainties.…”