COMPARISON OF (AL,GA)AS(110) GROWN BY MOLECULAR-BEAM EPITAXY WITH AS-2 AND AS-4

A comparison of Si-doped (Al,Ga)As grown on on-axis GaAs(110) with As, and As-4 is reported, together with a low temperature photoluminescen ce study of cleaved edge overgrown quantum well structures. Approximat ely 90% of Si atoms are active as donors under both facet-free and fac etted (110) growth conditions with As-2, whereas using As-4, the propo rtion is reduced to 40%-60%. It is shown that cleaving at the growth t emperature (480 degrees C) rather than room temperature is essential i f the cleaved interface is to be optically active. (C) 1996 American V acuum Society.