This paper deals with the nature and origin of the sim;1.41hyphen;eV emission band observed in the photoluminescence (PL) spectra ofnhyphen;GaAs samples subjected to diverse treatments. An investigation of the defect center responsible for this emission is carried by performing PL measurements on several samples (nsubstrates andn/n+epilayers) subjected to two types of heat treatments (rsquo;rsquo;preepigrowthrsquo;rsquo; and rsquo;rsquo;open tubersquo;rsquo;) at different temperatures and under varied conditions of surface protection. In light of the different experimental results we propose that the defect under consideration is a complex center formed by the association of arsenic vacancies and Si atoms (SiAs). Also, the existence of this defect in undoped epilayers grown on heavily siliconhyphen;doped substrates by the LPE technique, is tentatively explained as due to the contribution of the substrate during the epiprocess.
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