AVS 59th Annual International Symposium and Exhibition
    Electronic Materials and Processing Thursday Sessions
       Session EM-ThP

Paper EM-ThP4
Morpholigical Study of GaN Films Grown Under ALD Process Conditions as Well as Both Over- and Under- Saturated Growth Conditions

Thursday, November 1, 2012, 6:00 pm, Room Central Hall

Session: Electronic Materials and Processing Poster Session
Presenter: J.C. Revelli, University of Florida
Authors: J.C. Revelli, University of Florida
T.J. Anderson, University of Florida
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Gallium Nitride films were grown by pulsed deposition of GaCl3 and NH3 using nitrogen as both carrier and purge gas. The pulse and purge times leading to self-limiting, ALD-mode growth were investigated at 585°C. ALD growth conditions led to a constant thickness increment per cycle. The ALD conditions were determined to be a 3-6 second GaCl3 pulse, a 30 second NH3 pulse, and 30 second nitrogen purge times in between. The surface morphology of all films were examined by AFM. ALD films showed RMS surface roughness of 0.3nm, similar to that of the underlying (0002) sapphire substrate, while films that had a GaCl3 pulse below 3 seconds had an RMS roughness of 0.5mn and films oversaturated with GaCl3 had an RMS roughness of 1.2nm. This result suggests that AFM can be used as a rapid and non-destructive method to identify ALD growth conditions.