Project Title:

High-Growth-Rate, Atomic-Layer-Epitaxy Reactor for III-V Materials

08.20-6000
911825
High-Growth-Rate, Atomic-Layer-Epitaxy Reactor for III-V Materials
Spire Corporation
One Patriots Park
Bedford
MA
01730-2396
Naser H.
Karam
617-275-6000
JPL
NAS7-1169
172

08.20-6000
911825

Abstract:

High-Growth-Rate, Atomic-Layer-Epitaxy Reactor for III-V Materials
A new atomic layer epitaxy (ALE) reactor capable of growth rates exceeding 1 m/hr
will be designed and tested. The reactor will use continuously flowing, yet spatially
separated, gas streams and a moving substrate to expose the wafer surface to alternating
Group III and Group V fluxes. Its unique feature is the incorporation of both structural
and gas-curtain barriers to ensure fast and efficient removal of excess reactants
and reaction products. This will permit deposition to approach the very high speed
inherent in the adsorption/monolayer-coverage process that could, in principle, achieve
growth rates in the order of tens of micrometers each hour. Mechanical boundary layer
shearing coupled with efficient hydrogen purging will prevent gas-phase mixing and
degradation of ALE performance. Phase I will fit an existing reactor to a simplified
reaction chamber to demonstrate high-growth rate (> 1m/hour) ALE of gallium arsenide.
Phase II will expand the system to four independent reactants and four hydrogen purge
channels, making possible superlattice structures and doped alloys.
The reactor's high growth rates will make it possible, for the first time, to grow
complete, multi-micron thick device structures entirely by ALE. This may allow reproducible
growth of uniform, strained-layer quantum wells and make possible diode lasers that
emit at any desired wavelength in the range 0.5 m to 5.
atomic layer epitaxy (ALE), MOCVD, GaAs, AlGaAs