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Oklobia, Ochai

Publications and source records attributed to Oklobia, Ochai.

SnO2 Buffer Layers for High Efficiency CdSeTe/CdTe Devices

SnO2 buffer layers of different thickness were deposited onto TEC 15 Fluorine doped tin oxide coated glass substrates using rf magnetron sputtering. The buffer layers were then incorporated into Cu-doped CdSeTe/CdTe devices using a range of CdCl 2 activation treatments and CuCl2 annealing temperatures to determine the effects of buffer layer thickness on device performance. Results show that all devices fabricated with thinner buffer layers resulted in much better J - V characteristics than their thicker counterparts. This was mainly due to a reduced open-circuit voltage (Voc) when using thicker buffer layers. The best device produced a conversion efficiency of 16.59%, fill factor of 71.62%, Jsc of 28.44 mA/cm 2 and Voc of 814.23 mV.

buffer layers↗

12.3% Efficient Lifted-Off and Reconstructed As-Doped CdTe Thin Film Solar Cell

CdTe:As devices grown by MOCVD in the superstrate configuration have been reconfigured to a substrate structure, by employing a cleaving and reconstruction technique. Indium and aluminium doped Zinc oxide (IZO and AZO) layers were used as the transparent front interface without a metal grid. A substrate efficiency of 12.3% was realized with AZO front contact, retaining 80% of the superstrate device efficiency and an impressive approximately 99% of the open-circuit voltage. The IZO-based substrate device on the other hand performed at approximately 69 % retained efficiency. The crucial role of front interfaces is highlighted by the two contacts used here. The results in this work show promise for the development of highly efficient substrate CdTe:As devices.

II-VI semiconductor materials↗