کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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858253 | 1470747 | 2014 | 5 صفحه PDF | دانلود رایگان |
Due to the different thermal expansion coefficients in two materials, wafer curvature and residual stress are formed during the growth of an epi-GaN layer on Sapphire substrates. Using the finite element method to describe the realistic shape of wafer curvature on epi-GaN wafers, we examine the influence which different thickness and thermal expansion coefficients in the top epi-GaN layer have on wafer curvature reduction. In addition a new process to reduce wafer curvature and to relax residual stress is demonstrated. With an additional laser treatment on a sample surface after the growth of the top epi-GaN layer on a Sapphire substrate has taken place, the wafer curvature can be reduced from the original ∼ 45 μm to ∼ 37 μm in 2 inch wafer with an optimized surface structure design.
Journal: Procedia Engineering - Volume 79, 2014, Pages 323-327