Fabrication and characterization of InGaN p-i-n homojunction solar cell

Abstract

Xiamen Municipal Science & Technology Bureau [2006AA03Z110]In(x)Ga(1-x)N p-i-n homojunction solar cells with different In content are studied. The measured open circuit voltages (V(oc)) are 2.24, 1.34, and 0.96 V, for x=0.02, 0.12, and 0.15, respectively. By comparing the x-ray rocking curves, the I-V characteristics and the external quantum efficiencies, it's demonstrated that the deterioration of InGaN crystal quality for larger In contents causes the decrease of V(oc). The result demonstrates that reduction of defect is a key factor in the fabrication of nitride solar cell. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3254215

Multilayered InGaN/GaN structure vs. single InGaN layer for solar cell applications: A comparative study

“…In addition, despite a high absorption coefficient, InGaN layer thicknesses >100 nm are required for the absorption of more than 90% of the incident above-bandgap light [3]. To date, the maximum In incorporation in InGaN-based solar cells with thicknesses >100 nm grown by metalorganic vapor-phase epitaxy (MOVPE) ranges from 12% to 25% [4][5][6][7][8][9]. At such high In contents, due to the low crystalline quality of the InGaN layer, bandgap energy fluctuations and carrier recombination at localized states arise.…”

“…At such high In contents, due to the low crystalline quality of the InGaN layer, bandgap energy fluctuations and carrier recombination at localized states arise. The conversion efficiency of such devices is thus limited, leading to low values of the open-circuit voltage and short-circuit current density [8,9]. Thus, it is challenging to investigate new InGaN layer growth techniques that allow high In incorporation in thick layers while maintaining high crystalline quality.…”

Observation of positive thermal power coefficient in InGaN/GaN quantum well solar cells

“…The III-nitride materials system has many properties which make it an excellent candidate for high efficiency photovoltaic devices. [1][2][3][4] For instance, the band gap of the InGaN materials system spans nearly the entire solar spectrum (0.7 eV-3.4 eV), [5][6][7][8] creating the potential for making multijunction solar cells with a single ternary alloy system. Moreover, the absence of other mature materials with a direct band gap greater than $2.2 eV means that III-nitride materials hold great potential for use as the high energy cell in a multijunction solar cell.…”

Modeling of polarization effects in InGaN PIN solar cells

“…Several approaches have been suggested to generate the required depletion layer including homojunctions (Cai et al 2009), heterojunctions (Neufeld et al 2008;Jampana et al 2009) and graded layers (Brown et al 2010).…”