Electron Affinity and Bandgap Optimization of Zinc Oxide for Improved Performance of ZnO/Si Heterojunction Solar Cell Using PC1D Simulations

Abstract

For further uptake in the solar cell industry, n-ZnO/p-Si single heterojunction solar cell has attracted much attention of the research community in recent years. This paper reports the influence of bandgap and/or electron affinity tuning of zinc oxide on the performance of n-ZnO/p-Si single heterojunction photovoltaic cell using PC1D simulations. The simulation results reveal that the open circuit voltage and fill factor can be improved significantly by optimizing valence-band and conduction-band off-sets by engineering the bandgap and electron affinity of zinc oxide. An overall conversion efficiency of more than 20.3% can be achieved without additional cost or any change in device structure. It has been found that the improvement in efficiency is mainly due to reduction in conduction band offset that has a significant influence on minority carrier current.

High Photo Switching Response of n-ZnO/i-MoS2/p-Si Heterojunction Solar Cell

“…The minority carrier current density in the n-region and the p-region [3] and [4] J n = qnμ n ∇E c + μ n k B T∇n + qnD n,Th ∇ln (T)…”

“…The recent experiments have explored the heterojunction of ZnO-Si solar cell which promotes excellent nanostructure property and energy harvesting from the sun.However,surfacebarrier,surface/interface recombination are limiting Si based solar cell performance.The effective modulate the band structure could be tuned by fast switching response property and the trap density at the interface reduced,which could be promoted the better efficiency of the solar cell.In these above statement might be developed high performance solar cells.In this section explained, literature survey of various heterostructure based on ZnO,MoS2 and Si and their limitation. The interface defect density in the ZnO-Si interfaces is the main centre for recombination process and reducing the solar cell performance,The ZnO/p-Si heterojunction solar with low defect density in the range of 10 10 [cm -2 ] shows the solar cell performance parameters of Jsc,Voc and PCE :35.65[mA/cm 2 ],0.541[V] and 15.34% [1].The energy band offset of both conduction and valence band is used to increasing the solar cell performance.The optimized bandgap and electron affinity of the ZnO introduced the best values as 37.7[mA/cm 2 ] of Jsc,0.662[V] of Voc,0.815 of FF and the PCE is 20.34% [3].The poor surface defect density at the interfaces of ZnO/Si is the main centre for recombination process and the efficiency reached to low values.Bytuning of conduction band offset through insertion of buffer layer with lattice constant could be achieved better efficiency .The ZnO/ZnO-B/Si heterojunction solar cell reaches the efficiency 17.16% and Jsc:30.24[mA/cm 2 ].Voc:0.6758[V] and the FF:83.96%.The band alignment configuration could be tune the solar cell performance [5].…”

Nanoelectronic Materials, Devices and Modeling: Current Research Trends

“…In addition to the research in transistors and memory devices, this issue has collected important research on solar cells based on ZnO/Si heterojunctions [13], Bi-doped and Bi-Er co-doped optical fibers [14], high-performance graphene electrolyte double-layer capacitors [15], quantum-dot and sample-grating semiconductor optical amplifiers [16], a transmission method to determine the complex conductivity of thin strips [17], and a high-efficiency CMOS power amplifier with a dual-switching transistor [18].…”

A Fundamental Reason for the Need of Two Different Semiconductor Technologies for Complementary Thin-Film Transistor Operations

“…As can be seen in Figure 1, firstly, n-type inorganic materials, represented by conducting oxides (e.g., Zn-O [11]), have a high electron affinity (χ e ) around −4.5 eV [12]. This determines the energy level of the conduction band minimum.…”