Fabrication of 3-in GaN substrates by hydride vapor phase epitaxy using void-assisted separation method

• Published in: Journal of crystal growth Vol. 310; no. 1; pp. 5 - 7
• Main Authors: Yoshida, Takehiro, Oshima, Yuichi, Eri, Takeshi, Ikeda, Ken, Yamamoto, Shunsuke, Watanabe, Kazutoshi, Shibata, Masatomo, Mishima, Tomoyoshi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 04-01-2008; Elsevier
• Subjects: A1. Substrates; A3. Hydride vapor phase epitaxy; B1. Nitrides; B2. Semiconducting III–V materials; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Vapor phase epitaxy; growth from vapor phase; A3. Hydride vapor phase epitaxy; B1. Nitrides; B2. Semiconducting III–V materials; 78.60.Hk; 06.60.Ei; A1. Substrates; 61.72.Hh; 61.72.Ss; 06.60.Ei; 61.72.Hh; 61.72.Ss; 78.60.Hk; Crystal defects; Thick films; A1. Substrates; A3. Hydride vapor phase epitaxy; B1. Nitrides; B2. Semiconducting III-V materials; Secondary ion mass spectrometry; VPE; Hydrides; Gallium nitride; Voids; Dislocation density; Nitrides; Free-standing film; Carrier density; III-V semiconductors
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2007.10.014

By using the hydride vapor phase epitaxy and a void-assisted separation method, freestanding 3-in GaN substrates were successfully fabricated for the first time, and the process showed an excellent reproducibility. A thick GaN layer 3.2
in in diameter was easily separated from the base substrate. No cracks were generated during the separation process. The dislocation density was of the order of 10
6
cm
–2. The carrier density was approximately 1×10
18
cm
–3 and the mobility was 3.4×10
2
cm
2
V
–1
s
–1. The concentrations of impurities, estimated by secondary-ion mass spectrometry, were below the limit of detection, except for Si. The Si concentration was approximately 1×10
18
cm
–3, which is in good agreement with the carrier density.