Title :
Oxygen-Controlled Seed Layer in DC Sputter-Deposited ZnO:Al Substrate for Si Thin-Film Solar Cells
Author :
Seung-Yoon Lee ; Taehyun Hwang ; Woojin Lee ; Sangheon Lee ; Hongsik Choi ; Seh-Won Ahn ; Heon-Min Lee ; Byungwoo Park
Author_Institution :
Dept. of Mater. Sci. & Eng., Seoul Nat. Univ., Seoul, South Korea
Abstract :
Oxygen-controlled seed layer in Al-doped ZnO (ZnO:Al) thin films deposited by the industrially compatible dynamic dc magnetron sputter results in both enhanced electron mobilities and appropriate etched morphologies for the Si thin-film solar cells. At the relatively low deposition temperature of 300 °C, optimized ZnO:Al film grown on the seed layer has the carrier mobility of 45 cm2/V·s and proper postetching morphology with around 1-2-μm crater size. Reduced angular distribution of the (002) grains analyzed by the diffraction rocking curve is shown as the key structural feature for the improved carrier mobility. Finally, the performance of the microcrystalline Si solar cell on the developed ZnO:Al substrate shows high-efficiency potential of the tandem solar cell adapting this transparent conductive oxide substrate.
Keywords :
II-VI semiconductors; aluminium; electron mobility; elemental semiconductors; etching; semiconductor growth; semiconductor thin films; silicon; solar cells; sputter deposition; wide band gap semiconductors; zinc compounds; (002) grains; DC sputter-deposited ZnO:Al substrate; Si; ZnO:Al; carrier mobility; deposition temperature; diffraction rocking curve; electron mobility; etched morphology; microcrystalline solar cell; oxygen-controlled seed layer; reduced angular distribution; temperature 300 degC; thin-film solar cells; transparent conductive oxide substrate; Morphology; Photovoltaic cells; Silicon; Substrates; Surface morphology; Surface treatment; Zinc oxide; Al-doped ZnO; a-Si-based thin-film solar cells; sputtering; transparent conducting oxide;
Journal_Title :
Photovoltaics, IEEE Journal of
DOI :
10.1109/JPHOTOV.2014.2376052
