Title :
Current Transport in ZnO/Si Heterojunctions for Low-Cost Solar Cells
Author :
Yen, Tingfang ; Li, Meiya ; Chokshi, Nehal ; DeLeon, Robert L. ; Kim, Joondong ; Tompa, Gary ; Anderson, Wayne A.
Author_Institution :
Dept. of Electr. Eng., Buffalo Univ., NY
Abstract :
Thin film ZnO/Si structures are being studied as candidates for low cost solar cells. Total film thickness was about 5 microns. Crystallinity of both films was verified by X-ray diffraction. Photoluminescence spectroscopy showed a very strong peak to verify the crystallinity of the ZnO. ZnO films were studied for Hall effect mobility to reveal values of up to 200 cm2/V-s. In some cases, laser annealing was used to modify the ZnO films. Device structures were completed using the designs of metal/p-Si wafer, metal/ MIG-Si, and metal/ZnO/MIG-Si. These were chosen to evaluate current transport of the MIG-Si and the ZnO/MIG-Si interface. I-V-T data from 150degC to 425degC revealed quite different behaviors for the 3 designs. Conduction mechanisms included thermionic emission, recombination, space charge limited current (SCLC) due to a single trap and SCLC due to an exponential distribution of traps, seen for the ZnO/MIG-Si case
Keywords :
Hall mobility; II-VI semiconductors; X-ray diffraction; elemental semiconductors; laser beam annealing; photoluminescence; semiconductor heterojunctions; semiconductor thin films; silicon; solar cells; thermionic emission; zinc compounds; 150 to 425 C; Hall effect mobility; Si; X-ray diffraction; ZnO-Si; conduction mechanisms; current transport; laser annealing; low-cost solar cells; metal induced growth; photoluminescence spectroscopy; semiconductor heterojunctions; space charge limited current; thermionic emission; Costs; Crystallization; Hall effect; Heterojunctions; Photoluminescence; Photovoltaic cells; Semiconductor thin films; Spectroscopy; X-ray diffraction; Zinc oxide;
Conference_Titel :
Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
1-4244-0017-1
Electronic_ISBN :
1-4244-0017-1
DOI :
10.1109/WCPEC.2006.279806
