High quality 6-inch single-crystalline AlN template for E-mode HEMT power device

Abstract In the present work, the high uniform 6-inch single-crystalline AlN template is successfully achieved by high temperature annealing technique, which opens up the path towards industrial application in power device. Moreover, the outstanding crystalline-quality is confirmed by Rutherford backscattering spectrometry (RBS). In accompanied with the results from X-ray diffraction, the RBS results along both [0001] and reveal that the in-plane lattice is effectively reordered by high temperature annealing. In addition, the constant Φ epi angle between [0001] and at different depths of 31.54° confirms the uniform compressive strain inside the AlN region. Benefitting from the excellent crystalline quality of AlN template, we can epitaxially grow the enhanced-mode high electron mobility transistor (HEMT) with a graded AlGaN buffer as thin as only ~300 nm. Such an ultra-thin AlGaN buffer layer results in the wafer-bow as low as 18.1 μ m in 6-inch wafer scale. The fabricated HEMT devices with 16 μ m- L GD exhibits a threshold voltage ( V TH ) of 1.1 V and a high OFF-state breakdown voltage ( V BD ) over 1400 V. Furthermore, after 200 V high-voltage OFF-state stress, the current collapse is only 13.6%. Therefore, the advantages of both 6-inch size and excellent crystallinity announces the superiority of single-crystalline AlN template in low-cost electrical power applications.