Self organized growth of doped vertical quantum wells for normal incidence intersubband transitions

The self-organized growth of N-doped vertical AlGaAs quantum wells by metalorganic vapor phase epitaxy of a single doped AlGaAs layer on a submicron grating is described. Intersubband absorption at normal incidence is demonstrated in those vertical quantum wells. This opens new possibilities for infrared quantum well devices using intersubband transitions, including normal incidence infrared modulators. (C) 1996 Academic Press Limited