Low threshold planarized vertical-cavity surface-emitting lasers

Vertical-cavity surface-emitting lasers fabricated utilizing a self-aligned process to provide planarized contacts are discussed. A single 80-AA In/sub 0.2/Ga/sub 0.8/As strained quantum well was used in the active region. Emission was at 963 nm. Threshold currents under continuous-wave room temperature operation of 1.1 mA, at 4.0-V bias, were measured for numerous 12- mu m*12- mu m devices. Corresponding threshold current densities were 800 A/cm/sup 2/ (600 A/cm/sup 2/ for broad area devices). These are the lowest figures yet reported for this type of device. It was found that grading of the mirror had a marked effect on mirror resistance.<
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