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Provides information on a study examination the function of a thin microcrystalline p(...c-SiH) layer in a p-i-n hydrogenated amorphous silicon (a-Si:H) based solar cell. Methodology used to conduct the study; Information on circumstances at the ZNO/p front contact heterozygosity; Detailed information on the examination of p(...c-Si:H) fundamental material parameters; Conclusions reached on the study.

In amorphous/crystalline silicon heterojunction solar cells, an inversion layer is present at the front interface. By combining numerical simulations and experiments, we examine the contribution of the inversion layer to lateral transport and assess whether this layer can be exploited to replace the front transparent conductive oxide (TCO) in devices. For this, heterojunction solar cells of different areas (2 × 2, 4 × 4, and 6 × 6 mm2) with and without TCO layers on the front side were prepared. Laser-beam-induced current measurements are compared with simulation results from the ASPIN2 semiconductor simulator. Current collection is constant across millimeter distances for cells with TCO; however, carriers traveling more than a few hundred microns in cells without TCO recombine before they can be collected. Simulations show that increasing the valence band offset increases the concentration of holes under the surface of n-type crystalline silicon, which increases the conductivity of the inversion layer. Unfortunately, this also impedes transport across the barrier to the emitter. We conclude that the lateral conductivity of the inversion layer may not suffice to fully replace the front TCO in heterojunction devices. [ABSTRACT FROM AUTHOR]

The dynamic properties of an a-Si:H PIN structure were investigated by measuring the admittance of the device applying small harmonic signals under different forward and reverse voltages, and under dark as well as illumination conditions. A dynamic electrical SPICE model of the PIN device, which covers all these operation regimes, was developed. The model parameters are discussed and their physical background is addressed. Additionally, an analysis of device dynamic behaviour by applying larger non-harmonic signals is presented. [Copyright &y& Elsevier]

Thin PIN and NIP ultraviolet detectors are numerically and experimentally studied. The influence of the front contact design on the device performance as well as the transport properties of these thin diodes are investigated. Dark current measurements of PIN and NIP devices with thin I layer (dI<100 nm) indicate semi-exponential voltage dependent increase at reverse voltages, which can be explained by an electrical model applying a trap-assisted tunneling (TAT) mechanism. The same model explains the low spectral response at longer wavelengths that cannot be simulated using a standard electrical model. Comparison between Ag/PIN and Ag/NIP structure shows worse optical adjustment of Ag/NIP device mainly due to the lower optical gap of N-type a-Si:H layer. Thus, the Ag/PIN device exhibits a better performance than the Ag/NIP device. [Copyright &y& Elsevier]