Mh. Macdougal et al., DESIGN AND FABRICATION OF VCSELS WITH ALXOY-GAAS DBRS, IEEE journal of selected topics in quantum electronics, 3(3), 1997, pp. 905-915
A procedure for fabricating vertical-cavity surface-emitting lasers (V
CSEL's) with oxide-based distributed Bragg reflectors (DBR's) is prese
nted. An in-depth analysis of parameters and behavior unique to oxide
VCSEL's determines the device design. The development cycle time for t
hese devices is reduced through development of a method for post-growt
h analysis of the epitaxial stack reflectivity before device processin
g. Threshold currents as low as 160 mu A and resistances as low as 80
Omega are demonstrated using different device designs. The total optic
al loss of low-doped oxide VCSEL structures is 0.163% which is compara
ble to VCSEL designs based on all-semiconductor DBR's. The thermal res
istance of an 8 x 8 mu m VCSEL is measured to be 2.8 degrees C/mW, dem
onstrating that the presence of oxide layers does not act as a barrier
to heat flow out of the active region.