Rapid thermal processing (RTP) using halogen lamps for liquid encapsulated Czochralski grown GaAs doped with Si has been studied by deephyphen;level transient spectroscopy, capacitancehyphen;voltage, and photoluminescence measurements. RTP is performed at 700, 800, and 900thinsp;deg;C for 6 s with and without SiO2encapsulation. Three electron trapsED1(Ecminus;0.26 eV),ED2(Ecminus;0.49 eV), andED3(Ecminus;0.55 eV) are produced depending on RTP conditions. The trapED1 is observed in all RTP samples, and its depth profiles vary with RTP conditions. The decrease of the shallow donor concentration occurs for RTP samples above 800thinsp;deg;C, especially for those without encapsulation. It is thought that these results, which are peculiar to the RTP method, are related to the production of As interstitials and As vacancies by the large thermal stress induced by the rapid heating for RTP. The decrease of the concentration of trapEL2(Ecminus;0.81 eV) is not observed with RTP as reported in the furnace processing. This is due to the effect of the shorthyphen;time processing of RTP.
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