Sidewall growth by atomic layer epitaxy

Atomic layer epitaxy (ALE) has successfully been used to grow epitaxial layers over chemically etched grooves and dry etched sidewalls formed on GaAs(100) substrates. GaAs/InGaAs multilayers were deposited on V-shaped and inverted trapezoid-shaped grooves that were 4–5 μm deep and 8–20 μm wide. Growth conforming to the original sidewall surfaces was accomplished both on the chemically etched and on ion beam assisted etched surfaces. These features show distinct improvement over similar attempts by metalorganic chemical vapor deposition or molecular beam epitaxy. The ability of ALE to proceed in a self-limiting fashion on such structures is expected to lead to the realization of novel device concepts.