Irregularities in current-voltage characteristics of hydrogenated-amorphous-silicon-based barrier structures: Resonant tunnelling against hopping and filamentary conduction through the barriers

AbstractComputer simulations are reported of hydrogenated amorphous silicon germanium (a-SiGe:H) layers that make up the graded part of the intrinsic layer near the interfaces of a-SiGe:H solar cells. Therefore the graded part is approached with a ‘staircase’ bandgap profile, consisting of three layers within which the material properties are constant. Calibrated model parameters are obtained by matching simulation results of material properties of intrinsic a-SiGe:H single layers to measurements. Using the obtained model parameter sets subsequent simulations of p-i-n devices with intrinsic material similar to the single layers are matched to measured current-voltage characteristics. The changes in parameter values are evaluated as a function of optical gap.

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Dark current‐voltage characteristics of transverse asymmetric hydrogenated amorphous silicon diodes

Journal of Applied Physics ◽

10.1063/1.359980 ◽

1995 ◽

Vol 78 (5) ◽

pp. 3481-3487 ◽

Cited By ~ 21

Author(s):

R. Martins ◽

E. Fortunato

Keyword(s):

Amorphous Silicon ◽

Dark Current ◽

Hydrogenated Amorphous Silicon ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Hydrogenated Amorphous

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Capacitance Spectroscopy of Defects in a-SI:H/c-SI Heterostructures

MRS Proceedings ◽

10.1557/proc-557-463 ◽

1999 ◽

Vol 557 ◽

Cited By ~ 2

Author(s):

M. Rösch ◽

T. Unold ◽

R. Pointmayer ◽

G.H. Bauer

Keyword(s):

Amorphous Silicon ◽

Hydrogenated Amorphous Silicon ◽

Clear Correlation ◽

Temperature Dependent ◽

Capacitance Measurements ◽

Interface Defects ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Capacitance Spectroscopy ◽

Hydrogenated Amorphous

AbstractWe investigate defects at the interface in heterodiodes of hydrogenated amorphous silicon and monocrystalline silicon by frequency and temperature dependent capacitance measurements. The interpretation of the experimental results is supported by numerical simulations of capacitance experiments via transient calculations of defect charging and decharging in the diodes. A defined variation of waver surface treatments prior to amorphous silicon deposition shows a clear correlation of interface defects determined by capacitance measurements with current-voltage characteristics.

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Numerical Design of Ultrathin Hydrogenated Amorphous Silicon-Based Solar Cell

International Journal of Photoenergy ◽

10.1155/2021/7506837 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

F. X. Abomo Abega ◽

A. Teyou Ngoupo ◽

J. M. B. Ndjaka

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Amorphous Silicon ◽

Buffer Layer ◽

Defect Density ◽

Hydrogenated Amorphous Silicon ◽

Theoretical Work ◽

Silicon Based ◽

The Impact ◽

Hydrogenated Amorphous

Numerical modelling is used to confirm experimental and theoretical work. The aim of this work is to present how to simulate ultrathin hydrogenated amorphous silicon- (a-Si:H-) based solar cells with a ITO BRL in their architectures. The results obtained in this study come from SCAPS-1D software. In the first step, the comparison between the J-V characteristics of simulation and experiment of the ultrathin a-Si:H-based solar cell is in agreement. Secondly, to explore the impact of certain properties of the solar cell, investigations focus on the study of the influence of the intrinsic layer and the buffer layer/absorber interface on the electrical parameters ( J SC , V OC , FF, and η ). The increase of the intrinsic layer thickness improves performance, while the bulk defect density of the intrinsic layer and the surface defect density of the buffer layer/ i -(a-Si:H) interface, respectively, in the ranges [109 cm-3, 1015 cm-3] and [1010 cm-2, 5 × 10 13 cm-2], do not affect the performance of the ultrathin a-Si:H-based solar cell. Analysis also shows that with approximately 1 μm thickness of the intrinsic layer, the optimum conversion efficiency is 12.71% ( J SC = 18.95 mA · c m − 2 , V OC = 0.973 V , and FF = 68.95 % ). This work presents a contribution to improving the performance of a-Si-based solar cells.

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