High cubic phase purity of ELOG cubic GaN on [110] mask‐stripe‐patterned GaAs (001) substrates by MOVPE. Issue 7 (6th April 2017)

• Record Type: Journal Article
• Authors: Suwanyangyaun, Pattana; Thanachayanont, Chanchana; Sanorpim, Sakuntam; Onabe, Kentaro
• Is Part Of: Physica status solidi. Volume 254:Issue 7(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-04-06
• Subjects: crystal structure -- GaN -- metalorganic vapor phase epitaxy -- X‐ray diffraction; Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201600801
• Languages: English
• ISSNs: 0370-1972

Abstract

Abstract : Epitaxial lateral overgrowth (ELOG) of c‐GaN films was attempted on the [ 110 ] mask‐stripe‐patterned GaAs ( 001 ) substrates by MOVPE. Growth features, crystal quality, and generation of hexagonal phase inclusion were investigated as a function of growth time as well as thickness. At a growth temperature of 900 °C and a fill factor of 0.8, smooth ( 111 ) B sidewalls and ( 001 ) top surfaces continued for a longer growth time. This resulted in a large reduction of hexagonal phase inclusion, which was confirmed by X‐ray reciprocal space mapping. To quantify the amount of hexagonal phase inclusion in the ELOG c‐GaN films with large variation in thickness, the effects of GaN X‐ray absorption and of the diffraction geometry were investigated. An amount of hexagonal phase inclusion as low as 3.1% was achieved at a growth time of 30 min (3.5 μm). The amount was found to decrease from 55.5 to 3.1% and 21.1%, when the film thickness increased from 1.4 to 3.5 μm and 12.0 μm, respectively.