Growth of GaN on Patterned Sapphire Substrate with High-Index Facets. (1st January 2015)

• Record Type: Journal Article
• Authors: Chang, Sheng-Chieh; Chen, Chien-Chih; Chang, Tsu-Chi; Lin, Kun-Lin; Lu, Tien-Chang; Chang, Li; Wu, YewChung Sermon
• Is Part Of: ECS journal of solid state science and technology. Volume 4:Number 12(2015)
• Page Start: R159
• Page End: R161
• Publication Date: 2015-01-01
• Subjects: GaN -- patterned sapphire substrate -- Semipolar; Solid state chemistry -- Periodicals; Electronics -- Materials -- Periodicals; Electrochemistry -- Periodicals; 541.0421
• DOI: 10.1149/2.0201512jss
• Languages: English
• ISSNs: 2162-8777

Abstract

Abstract : Periodic pyramidal array patterned sapphire substrate (PSS) with various inclined facets was fabricated by wet etching. It was found that {34 ̄ 17}, {41 ̄ 3 ̄ 18}, and {123 ̄ 5} facets are exposed on the PSS structure after etching. GaN grown on the PSS by metal-organic chemical vapor deposition was found to have a semi-polar orientation by structural characterization with scanning and transmission electron microscopy. Also, the results show that GaN is mainly grown on the {123 ̄ 5} sapphire facet with the orientation relationship between GaN and sapphire as (011 ̄ 4 ̄ )GaN // (33 ̄ 06 ̄ )sapphire and [022 ̄ 1]GaN // [112 ̄ 0]sapphire, and the dislocation density in the grown GaN decreased with thickness. In addition, photoluminescence and catholuminescence measurements show only strong near-band-edge emission from the semi-polar GaN on the {123 ̄ 5} sapphire facet.