ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The influence of different CdTe substrate preheats prior to II-VI molecular beam epitaxial growth on surface stoichiometry and oxygen contamination has been studied using x-ray photoelectron spectroscopy. For 15 min preheats with temperatures ranging from 100 to 450 °C, the cadmium to tellurium ratio and the oxide overlayer thickness of (100) CdTe surfaces was determined. A preheat temperature of 200 °C is found to produce optimum stoichiometry. For lower temperatures the CdTe surface is still tellurium rich, as left after etching with bromine-methanol. For higher temperatures, cadmium evaporates faster than tellurium, leaving again a tellurium-rich surface. The oxygen contamination remains nearly unchanged for temperatures below 250 °C. Oxygen starts to blow off for preheat temperatures above 250 °C, with a steep decrease between 250 and 350 °C. For preheat temperatures higher than 350 °C, the oxygen contamination drops below the detection limit.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.101028
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