Ml. Dotor et al., QUANTUM-WELL LASERS WITH INAS MONOLAYERS IN THE ACTIVE REGION GROWN AT LOW-TEMPERATURE BY ATOMIC LAYER MOLECULAR-BEAM EPITAXY, Journal of crystal growth, 127(1-4), 1993, pp. 46-49
Strained-layer quantum well lasers have been grown at low substrate te
mperature (350-degrees-C) by atomic layer molecular beam epitaxy (ALMB
E). A series of five separate confinement laser structures has been gr
own. Active regions consist of 80 A of GaAs in which n InAs monolayers
are inserted separated by 3 GaAs monolayers, with n = 1, 3, 5 and 7.
A sample with 100 angstrom Ga0.8In0.2As active region was also grown a
t low temperature for comparison. Structural quality is studied by X-r
ay diffraction. Optical characterization has been performed, and the r
esults are compared with calculations by a four-band envelope-wavefunc
tion method. Broad area lasers have been fabricated, and their perform
ances are studied as a function of increasing InAs content. Lasers wit
h GaAs active regions including InAs monolayers show threshold current
s comparable to that of the GaInAs alloy laser, for n less-than-or-equ
al-to 5 monolayers. These results prove the feasibility of ALMBE for t
he low temperature growth of strained layer lasers.