کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9829751 1524498 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Seeded growth of bulk AlN crystals and grain evolution in polycrystalline AlN boules
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Seeded growth of bulk AlN crystals and grain evolution in polycrystalline AlN boules
چکیده انگلیسی
Large AlN crystals were grown by powder sublimation in a nitrogen atmosphere at low supersaturation and growth rates of 0.1-0.3 mm/h. The starting deposition surface was a sintered TaC disc. An appropriate adjustment of the system pressure and source-seed temperature gradient during the early stages of growth allowed epitaxial re-growth on AlN seeds that had been exposed to air. Single-crystalline AlN grains of 1 cm in size were achieved through multiple sublimation growth runs conducted at P=500Torr and growth temperatures of 2050-2150 °C. Elemental analysis of impurities in the grown AlN boules confirmed low oxygen contamination levels of ∼1019/cm3. No discontinuities were introduced in the structural defect distribution in the individual single-crystalline grains by the multiple re-growth steps. Absence of preferred growth directions of grains suggest the epitaxial re-growth process is suitable for seeded single-crystal growth in any orientation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Crystal Growth - Volume 279, Issues 1–2, 15 May 2005, Pages 13-19
نویسندگان
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