Generation and applications of a broad atomic oxygen beam with a high
flux-density via collision-induced dissociation of O2
Abstract
We detail the generation of a pulsed atomic oxygen (AO) broad beam with
a high flux-density via collision-induced dissociation of
O2 to support practical industrial exploitation of AOs,
particularly for facilitating 2-dimenstional oxidation/etching at a fast
rate of one-monolayer per second in an area ≥1000cm2.
This innovation fuses the following interdisciplinary concepts: (a) a
high density of O+ can be produced in an
electron-cyclotron-resonance (ECR) O2 plasma; (b)
O+ can be extracted and accelerated with an
aperture-electrode in the plasma; (c) O+ with adequate
kinetic energy can initiate a cascade of gas-phase collisions in the
presence of O2; (d) collision-induced dissociation of
O2 yields AOs with adequate kinetic energy which can
cause additional collision-induced dissociation of O2.
Computational simulations of such collisions, with both ab initio
molecular dynamics and direct simulation Monte Carlo methods, are used
to guide the experimental generation of the proposed AO-beam. We
experimentally demonstrate the highest known AO mean flux-density of
about 1.5×1016 atoms cm-2
s-1 in a broad-beam, and use it to oxidatively modify
a self-assembled molecular layer of siloxane on a silicon wafer. In
addition, we also demonstrate the growth of
Al2O3 through an AO-assisted atomic
layer deposition process at a room temperature.