Persistent photoconductivity in doping-modulated multilayers and compensated thin films of hydrogenated amorphous silicon

Light and thermally induced metastabilities in electrochemically etched nanocrystalline porous silicon

“…This is also in agreement with Ben- Furthermore, our short exposures results are in agreement with other authors [6,7] and our long exposures results are in agreement with Matsumoto et al [11] who also found that for long exposures dangling bond density (ESR) increases and PL decreases. A similar effect on DC for short as well as long exposures is observed in doping modulated and compensated a-Si:H [38,39].…”

Influence of polystyrene coating on the photo-degradation of amorphous silicon

“…1 and 2) is known in the literature as the inverse Staebler-Wronski effect [3] that is similar to the persistent photoconductivity (PPC) observed in doping modulated multi-layered [4] and compensated [5] a-Si:H thin films. This manifests itself as an increase in the dark current and photocurrent after LS, which persists for several hours, even at 300 K. Aker and Fritzsche [3] observed a similar increase in dark current for their boron doped a-Si:H samples, upon light soaking.…”

“…This is unlike nc-Si, where surface plays the predominant role. However, boron doped a-Si:H [a-Si:H(B)] samples show an inverse Staebler-Wronski effect [3] that is similar to the persistent photoconductivity (PPC) observed in multi-layered [4] and compensated [5] a-Si:H thin films and has been attributed [3] to the oxide layer at the surface. Further, it appears from the study of surface photo-voltage measurements [6] that even in undoped a-Si:H, SWE involves changes in the surface as well as the bulk.…”

Effect of illumination on hydrogenated amorphous silicon thin films doped with chalcogens

“…A metastable excess conductance, which can be enhanced by a brief light exposure up to several orders of magnitude compared to the initial dark conductivity, has been observed in compensated aSi:H films [34][35][36][37][38][39] as well as in doping modulated multilayers of aSi:H [35,38,[40][41][42][43]. This metastable excess conductance, called persistent ph (PPC), decays slowly over several days at room temperature and disappears by annealing near 100°C in multilayered films and 200°C in compensated films [24].…”