We report the realization of high-performance long-wavelength infrared detectors with n-on-p polarity based on InAs/GaSb type-II superlattices grown by metalorganic chemical vapor deposition (MOCVD) on InAs substrate. In a normal n-on-p device with PNn heterostructure, Zinc (Zn) is found to diffuse into the critical n-type barrier layer and leads to a high leakage current. By inserting a 200 nm undoped spacer layer after the p-type region is grown, Zn diffusion is completely confined in the spacer layer. The n-on-p device with the spacer shows performances equivalent to those of a p-on-n counterpart, with a dark current density of $6\times 10^{-4}$ A/cm² at −0.1 V at 80 K, a peak quantum efficiency of ~24%, and 100% cut-off wavelength of $\sim 12~\mu \text{m}$ .

中文翻译：

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具有 n-on-p 极性的 InAs 衬底上的长波长 InAs/GaSb 超晶格探测器

我们报告了基于 InAs/GaSb II 型超晶格的具有 n-on-p 极性的高性能长波长红外探测器的实现，该超晶格通过在 InAs 衬底上通过金属有机化学气相沉积 (MOCVD) 生长。在具有 PNn 异质结构的普通 n-on-p 器件中，发现锌 (Zn) 扩散到关键的 n 型势垒层并导致高漏电流。通过在 p 型区生长后插入 200 nm 未掺杂的间隔层，Zn 扩散被完全限制在间隔层中。带有隔离物的 n-on-p 器件的性能与 p-on-n 对应器件的性能相当，暗电流密度为 $6\乘以 10^{-4}$ A/cm ² at -0.1 V at 80 K，峰值量子效率为~24%，100% 截止波长为 $\sim 12~\mu \text{m}$ .