The kinetics of atomic layer epitaxy (ALE) of GaAs utilizing trimethylgallium and arsine are described. The results show that saturated monolayer growth can be achieved-in the temperature range 445°C -485°C and that high quality materials can be grown.. Hybrid A1GaAs/GaAs heterostructures have been grown utilizing ALE for the active regions and conventional metalorganic chemical vapor deposition (MOCVD) for the confining regions that yield high quality quantum wells and low threshold quantum well lasers.

Atomic layer epitaxy (ALE) is a relatively new crystal growth technique which allows control of the growth process at the monolayer level through a self-limiting, surface-controlled growth mechanism. We report here the use of ALE to grow high-quality GaAs/AlGaAs quantum wells and the first successful demonstration of an injection laser with a quantum well active region grown by ALE. Room-temperature threshold current densities as low as 640 A/cm2 have been achieved in nonoptimized separate confinement structures.

A new technique is demonstrated for the formation of narrow active regions in quantum well lasers. In temperature engineered growth (TEG), the substrate temperature is varied during the growth of epitaxial layers by metalorganic chemical vapor deposition (MOCVD) on nonplanar substrates, allowing two-dimensional control of device features. Buried heterostructure designs with submicron active region stripe widths are obtained without the need for fine process control of lateral dimensions. The contact area above the active region is coplanar with the surrounding surface and wide enough to allow easy contacting and heat sinking. Carrier confinement is accomplished by lateral thickness variation of the quantum well active region resulting in a local strip of minimum band gap. Lasers grown in this manner exhibit cw threshold currents as low as 3.8 mA (3.4 mA pulsed), having an as-grown active region width of 0.5 μm. The near-field optical profile indicates stable, single transverse mode operation and minimal current leakage in these devices.

The use of trimethylgallium (TMGa) and tertiarybutylarsine (TBAs) in atomic layer epitaxy (ALE) and laser-assisted atomic layer epitaxy (LALE) of GaAs is studied for the first time. TBAs is found to be a direct and suitable replacement for arsine (AsH3) in achieving monolayer self-limiting growth. Carbon contamination in the GaAs films grown by LALE using TMGa and TBAs is greatly reduced relative to those using TMGa and AsH3. Laser structures single GaAs quantum wells grown by ALE and LALE using TBAs exhibit threshold current density as low as 300 and 520 A/cm2, respectively.

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