A dopant-free p-type Al_xGa_1–xN (x = 0.1~0) layer, achieved by polarization induced three-dimensional hole gas, was introduced into the structure of AlGaN npn heterojunction phototransistors (HPTs) as the p-base. The fabricated HPTs with a junction diameter of $150~\mu \text{m}$ exhibit a sharp cutoff with a 360/375-nm rejection ratio of more than 3 orders of magnitude and a responsivity of $5\times 10^{{3}}$ A/W at 360 nm under the 2 V collector bias. A high optical gain of $6.5\times 10^{{4}}$ was obtained at 10 V bias. These results demonstrate the feasibility of polarization-doped p-base in developing high-performance AlGaN UV HPTs.

中文翻译：

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具有无掺杂偏振掺杂 P 基极的高性能 AlGaN 异质结光电晶体管

通过极化诱导三维空穴气体实现的无掺杂 p 型 Al _x Ga _1-x N (x = 0.1~0) 层被引入到 AlGaN npn 异质结光电晶体管 (HPT) 的结构中作为 p-根据。制造的 HPTs 的结直径为 $150~\mu \text{m}$ 具有超过 3 个数量级的 360/375 nm 抑制比和响应度 $5\乘以 10^{{3}}$ 在 2 V 集电极偏压下 360 nm 处的 A/W。高光学增益 $6.5\乘以 10^{{4}}$ 在 10 V 偏压下获得。这些结果证明了偏振掺杂 p 基极在开发高性能 AlGaN UV HPT 中的可行性。