Schottky and P-I-N hydrogenated amorphous silicon structures: fabrication, characterization and modeling
Schottky, and P-I-N solar cells have been fabricated on a-Si:H films deposited on metal substrates utilizing dc and rf glow discharge decomposition of silane. These devices have been characterized by spectral response, dark and illuminated I-V, I-V-T, C-V, G-V and C-V-T measurements. Optimization parameters for the cell fabrication include thickness of the I-layer, thickness and doping of N- and P-layers (for P-I-N structures), substrate type and temperature, barrier metal (for Schottky structures) and top electrode metal (for P-I-N structures). Photovoltaic performance of the optimum configurations has been reported. A 6.4% efficient ITO/N-P/SS a-Si:H solar cell has been fabricated as a result of the above studies. Spectral response measurments were used to calculate the photogenerated carrier collection efficiency as a function of wavelength and illumination level. These measurements have also been used to identify the principal collection region in the P-I-N structures. A model incorporating the dual behavior of the I-layer is presented to develop the terminal I-V, C-V and G-V characteristics of Schottky structures. Illuminated C-V, G-V and C-V-T data are explained on the basis of this model. This model has yielded information regarding the density and distribution of traps in the I-layer and the relative voltage drops across the depletion and neutral bulk regions under an external bias. Based on the above study, a design guideline is ultimately presented to further improve the efficiency of a-Si:H solar cells.
- OSTI ID:
- 6803463
- Country of Publication:
- United States
- Language:
- English
Similar Records
Modeling of hydrogenated amorphous silicon Schottky structures using capacitance-voltage and conductance-voltage measurements
Characteristics of different thickness a-Si:H/metal Schottky barrier cell structures -- Results and analysis