Promotion of lateral growth of GaN crystals on point seeds by extraction of substrates from melt in the Na-flux method. (27th March 2019)

• Record Type: Journal Article
• Authors: Imanishi, Masayuki; Murakami, Kosuke; Yamada, Takumi; Kakinouchi, Keisuke; Nakamura, Kosuke; Kitamura, Tomoko; Okumura, Kanako; Yoshimura, Masashi; Mori, Yusuke
• Is Part Of: Applied physics express. Volume 12:Number 4(2019)
• Publication Date: 2019-03-27
• Subjects: GaN -- bulk crystal -- Na-flux -- point seed -- flux film; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.7567/1882-0786/ab0db6
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: In a previous study, we successfully obtained large-diameter, low-dislocation-density GaN wafer using the Na-flux multi-point seed (MPS) technique. However, the lattice constants of the GaN wafer grown by this technique expanded due to oxygen concentration in pyramidal facets. We here invented a breakthrough technique for the promotion of lateral growth, and succeed in suppressing pyramidal facet growth by residual flux formed after extraction of the MPS-GaN substrate from the Na-Ga melt in a crucible. The surface of the grown wafer was fully composed of the c -plane and showed low oxygen concentration, so expansion of lattice constants could be successfully prevented.