Title :
Polycrystalline thin films of Hg1-xZnxTe for use in multijunction solar cells
Author :
Arshed, S. ; Miles, R.W. ; Hill, R.
Author_Institution :
Newcastle Polytech., UK
Abstract :
Thin films of Hg1-xZnxTe were deposited onto Corning 7059 glass substrates using the coevaporation of HgTe with ZnTe. Layers were produced with bandgaps in the range of 0.6-2.25 eV by altering the alloy composition. The layers had absorption coefficients >105/cm1 and as high as 6×105 cm1 in samples with Eg>1.5 eV. The samples were p-type at 300 K with low resistivities (≈0.5 Ωcm) and Hall mobilities in the range 2-12 cm2/V1s1 for layers <0.5-μm thick. Arrhenius plots of the resistivities gave two straight lines corresponding to an activation energy, of 50 ±5 meV for temperatures >220 K and an activation energy of 7 ±4 meV for temperatures <220 K. The layers consisted of columnar grains, and the grain size increased with film thickness and with postgrowth annealing in argon. Heterojunctions with CdS and Cd1-xZnxS window, layers had I-V characteristics which were rectifying, and these devices exhibited the photovoltaic effect
Keywords :
II-VI semiconductors; mercury compounds; semiconductor thin films; solar cells; zinc compounds; Arrhenius plots; Corning 7059 glass substrates; Hall mobility; Hg1-xZnxTe multijunction solar cells; I-V characteristics; absorption coefficients; activation energy; coevaporation; columnar grains; film thickness; grain size; polycrystalline thin films; postgrowth annealing; resistivity; Conductivity; Glass; Mercury (metals); Photonic band gap; Sputtering; Substrates; Tellurium; Temperature; Transistors; Zinc compounds;
Conference_Titel :
Photovoltaic Specialists Conference, 1990., Conference Record of the Twenty First IEEE
Conference_Location :
Kissimmee, FL
DOI :
10.1109/PVSC.1990.111733
