EFFECTS OF SUBSTRATE MISORIENTATION ON TRIPLE-PERIOD ORDERING IN ALINAS

Substrate misorientation effects on triple-period (TP) ordering in Al0 .48In0.52As were studied. When AlInAs was grown on a (001) InP substra te misoriented by 4 degrees in the [($) over bar 1 ($) over bar 11]A d irection, TP-type ordering formed more strongly in the [($) over bar 1 ($) over bar 11]A direction than in the [111]A direction. This asymme tric formation of TP-type ordering demonstrates that the step-arrays d escending in the [($) over bar 1 ($) over bar 10] direction play an im portant role in TP-type ordering formation in the [($) over bar 1 ($) over bar 11]A direction. When AlInAs was grown at a higher temperature on a (001) InP substrate misoriented by 4 degrees in the [($) over ba r 1 ($) over bar 11]B direction, CuPt-type ordering was formed more st rongly in the [($) over bar 111]B than in the [1 ($) over bar 11]B dir ection. The importance of the [($) over bar 110] step in CuPt-type ord ering, which is well established in GaInP systems, was thus reconfirme d in this study on AlInAs.