Development of a 2-inch GaN wafer by using the oxide vapor phase epitaxy method

Abstract

Abstract From the previous studies, one of the challenges in the oxide vapor phase epitaxy (OVPE) method was suppressing poly-crystal generation for thick GaN growth. In this study, thick GaN growth was realized by controlling the supersaturation ratio using thermodynamic analysis, and an OVPE-GaN wafer of 300 μ m-thick was obtained. As a result of evaluating the quality of the OVPE-GaN wafer, it was confirmed that both the high oxygen concentration and the high crystallinity were achieved. The resistivity was 7.75 × 10 −4 Ω cm and the threading dislocation density (TDD) was 8.8 × 10 4 cm −2 . It was newly found that the OVPE method can reduce TDD from the order of 10 6 cm −2 to the order of 10 4 cm −2 with a grown thickness of less than 500 μ m. From these results, it was proved that the OVPE method has a great potential of manufacturing low resistivity and low TDD GaN wafers.