ATOMIC LAYER EPITAXY FOR THE GROWTH OF HETEROSTRUCTURE DEVICES

Atomic layer epitaxy (ALE) is a regime of metalorganic vapor phase epitaxial growth in which uniform growth of ultra-thin epitaxial layers by a self-limiting monolayer by monolayer deposition is achieved. In this paper ALE has been applied to the growth of single crystal GaAs, AlAs and GaAS/AlGaAs heterostructures and devices. Data are presented that show one monolayer uniformity in ultra-thin layers grown by ALE. The dependence of growth rate on reactant flows and temperature are described. Cleaved corner TEM analysis of ALE epitaxial layer thickensses demonstrates the 'digital' nature of the deposition process. The low temperature photoluminescence (PL) of ALE grown GaAs quantum wells exhibit narrow line intrinsic luminescence with linewidths comparable to the best reported values by conventional MOCVD. Quantum well lasers with ALE grown active regions have been demonstrated with laser thresholds as low as 400 A/cm2.