Examination of anisotropic stress state evaluation in III-V compound semiconductors by oil-immersion Raman spectroscopy

2014 Fiscal Year Final Research Report

• Project/Area Number: 25790049
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Crystal engineering
• Research Institution: Meiji University
• Principal Investigator: KOSEMURA Daisuke 明治大学, 研究・知財戦略機構, 客員研究員 (00608284)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: III-V化合物半導体 / GaN / 非極性面 / 液浸ラマン分光法 / 表面増強ラマン分光法 / フォノン / ウルツ鉱構造 / カソードルミネッセンス

Outline of Final Research Achievements

Anisotropic stress states at the surfaces of GaN samples were studied. Strain-shift coefficients which are important to accomplish this study were introduced by using a tool for strain introduction as well as methodology with Raman spectroscopy and X-ray diffraction. The information at the surface of the GaN sample was extracted by the combination of oil-immersion Raman and surface-enhanced Raman. The Raman polarization selection rules not only for c-plane but also for a-, m-, and s-plane GaN were experimentally and numerically examined. An anomalous behavior of the E1TO peak excited by oil-immersion Raman was observed, which was attributed to the phonon mixing effect. The anisotropic stress state in the GaN can be evaluated using this phonon mixing effect. The results described above include important insights regarding the stress evaluation in GaN, which can contribute to the technology of measurement and crystal growth for GaN related materials.

Free Research Field

半導体電子物性