Vertical Architecture Solution-Processed Quantum Dot Photodetectors with Amorphous Selenium Hole Transport Layer
Vertical Architecture Solution-Processed Quantum Dot Photodetectors with Amorphous Selenium Hole Transport Layer
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DOI：
10.1021/acsphotonics.2c01353
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发表时间：
2022-12-29
期刊：
影响因子：
7
通讯作者：
Goldan, Amir H.
中科院分区：
文献类型：
--
作者：
Mukherjee, Atreyo;Kannan, Haripriya;Goldan, Amir H.
胶体量子点（CQD）由于量子限制和大的振荡器强度而提供宽的光谱可调谐性和高的吸收系数，其沿着溶液可加工性，允许用于制造光子器件的容易的、低成本的和室温的沉积技术。然而，许多溶液处理的CQD光电探测器器件表现出低的比探测率和慢的时间响应。为了实现改进的光电探测器特性，限制载流子复合和增强光生载流子分离是至关重要的。在这项研究中，我们开发并提出了一种替代的垂直堆叠光电探测器，其中我们使用的解决方案处理的量子点光转换层耦合到非晶硒（a-Se）宽带隙电荷传输层，能够表现出单载流子空穴碰撞电离，并与有源矩阵读出电路兼容。该a-Se硫族化物传输层使得能够制造高性能和可靠的溶液处理量子点光电探测器，其具有增强的电荷提取能力、高比探测率和高的光电转换效率。（D* 0.5-5 x 1012 Jones），快速3 dB电气带宽（3 dB BW 22 MHz）、低暗电流密度（JD 5-10 pA/cm 2）、低噪声电流（20-25 fW/Hz 1/2）和在测量的可见电磁光谱（405-656 nm）上的高线性动态范围（LDR 130-150 dB）。
Colloidal quantum dots (CQDs) provide wide spectral tunability and high absorption coefficients owing to quantum confinement and large oscillator strengths, which along with solution processability, allow a facile, low-cost, and room temperature deposition technique for the fabrication of photonic devices. However, many solution-processed CQD photodetector devices demonstrate low specific-detectivity and slow temporal response. To achieve improved photodetector characteristics, limiting carrier recombination and enhancing photogenerated carrier separation are crucial. In this study, we develop and present an alternate vertical-stack photodetector wherein we use a solution-processed quantum dot photoconversion layer coupled to an amorphous selenium (a-Se) wide-bandgap charge transport layer that is capable of exhibiting single-carrier hole impact ionization and is compatible with active-matrix readout circuitry. This a-Se chalcogenide transport layer enables the fabrication of highperformance and reliable solution-processed quantum dot photodetectors, with enhanced charge extraction capabilities, high specific detectivity (D* 0.5-5 x 1012 Jones), fast 3 dB electrical bandwidth (3 dB BW 22 MHz), low dark current density (JD 5-10 pA/cm2), low noise current (in 20-25 fW/Hz1/2), and high linear dynamic range (LDR 130-150 dB) across the measured visible electromagnetic spectrum ( 405-656 nm).