Centimeter-Sized Bulk GaN Single Crystals Grown by the Na-Flux Method with a Necking Technique

详细信息    查看全文

• 作者：Mamoru Imade ; Kosuke Murakami ; Daisuke Matsuo ; Hiroki Imabayashi ; Hideo Takazawa ; Yuma Todoroki ; Akira Kitamoto ; Mihoko Maruyama ; Masashi Yoshimura ; Yusuke Mori
• 刊名：Crystal Growth & Design
• 出版年：2012
• 出版时间：July 3, 2012
• 年：2012
• 卷：12
• 期：7
• 页码：3799-3805
• 全文大小：562K
• 年卷期：v.12,no.7(July 3, 2012)
• ISSN：1528-7505

文摘

Centimeter-sized bulk GaN single crystals with large dislocation-free areas were fabricated by the Na-flux method with a necking technique. This necking, which is the key technique in Czochralski growth of dislocation-free Si ingots, was realized using a newly developed GaN point seed. Structural properties of grown crystals were investigated using panchromatic cathodoluminescence (CL) measurements and X-ray diffraction. Prism-shape and well-faceted bulk GaN crystals with dimensions as large as 0.85 cm (width) and 1 cm (length) were grown by this technique. The GaN single crystal grown for 400 h have full-width at half-maximum values for c// and c as narrow as 42.8 and 32.5 arcsec, respectively, indicating an extremely high quality. Panchromatic CL images of (0001) GaN wafers sliced from grown crystals revealed that large areas of the wafers were dislocation free. We concluded that the necking technique in Na flux GaN growth may be a major breakthrough for fabricating large dislocation-free GaN ingots.