Pentacene thin layers were deposited on Si with the native oxide at 80°C
by remote-plasma-assisted deposition (RPAD) using hydrogen-plasma cell to
supply atomic hydrogen radicals. The deposition rate was increased by RPAD comparing
to that by non-excited hydrogen gas supply whereas thermal evaporation rate of
pentacene from crucible was same in the both process. DFM and XRD studies
showed the grain laterally grew in the thin film phase with the size above 10 μm
by RPAD. First-principles molecular orbital calculations suggested pentacene is evaporated from crucible as the trimer or larger cluster but
atomic hydrogen penetrated into the cluster enhances cracking of pentacene
clusters to the monomer.
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