No abstract

No abstract

The photovoltaic behaviour of metal/n-InGaN Schottky junction solar cells with low-and high-level injection conditions are explored by using voltage model. Four metals Ni-Au, Ni, Au and Pt are used as Schottky contact with n-InGaN and Schottky junction solar cell studied for open-circuit voltage (V oc ) and short circuit current density (J sc ) with a variation of Indium composition in n-InGaN. The cut-off value of Indium composition in n-InGaN is 36, 42, 55 and 70 % for Ni-Au, Ni, Au and Pt, respectively. The effects of doping density and surface recombination velocity on V oc and J sc are also explored. Model predict increment in V oc and J sc under high-level injection condition as compared to low-level injection condition with / = 2 9 10 17 cm -2 s -1 photon flux. The metal, Pt, is found to be a better choice in terms of making Schottky junction with n-InGaN. The concentration of donor atoms in n-InGaN plays an important role in both types of injection. The donor concentration should preferably be kept higher ([10 16 cm -3 ) to get higher V oc .

High quality graphene film is fabricated using mechanical exfoliation of highly-oriented pyrolytic graphite. The graphene films on glass substrates are characterized using field-emission scanning electron microscopy, atomic force microscopy, Raman spectroscopy, UV-vis spectroscopy and Fourier transform infrared spectroscopy. A very high intensity ratio of 2D to G-band (to approximately 1.67) and narrow 2D-band full-width at half maximum (to approximately 40 cm(-1)) correspond to the bi-layer graphene formation. The bi-layer graphene/p-GaN/n-InGaN/n-GaN/GaN/sAl2O3 system is studied theoretically using TCAD Silvaco software, in which the properties of exfoliated bi-layer graphene are used as transparent and conductive film, and the device exhibits an efficiency of 15.24% compared to 13.63% for ITO/p-GaN/n-InGaN/n-GaN/GaN/Al2O3 system.

No abstract