【摘要】 可见-近红外响应的正照射单元型InGaAs光电探测器具有无需倒焊互连、封装结构简单、光谱响应范围宽等优势。针对InP帽层减薄工艺导致的表面态增加及表面复合引起的暗电流增大问题,文章分析了P型掺杂浓度与表面复合速率（SRV）对薄帽层器件灵敏度的影响机制。仿真结果表明:当帽层厚度由500 nm减薄至100 nm时,0.7μm波长处的量子效率从6%提高至41%,但暗电流密度由0.2 nA/cm²增至16.7 nA/cm²。SRV对器件性能影响显著,当SRV从3×10³ cm/s降至1×10³ cm/s时,峰值探测率（D^*）由2.31×10¹² cm·Hz^1/2·W^-1提升至3.7 8×10¹² cm·Hz^1/2·W^-1。实验采用表面钝化工艺后,探测器暗电流得到有效抑制,峰值D^*从2.6×10¹² cm·Hz^1/2·W^-1提高至4.1×10¹² cm·Hz^1/2·W^-1。研究结果表明,改进表面钝化工艺以降低SRV对于提升正照射可见-近红外InGaAs探测器性能具有重要意义。更多还原

【Abstract】 Front-illuminated visible-near-infrared（Vis-NIR） InGaAs single-element photodetectors offer advantages, such as no need for flip-chip bonding, simplified packaging structure, and broad spectral response. To address the increase in dark current caused by elevated surface states and surface recombination following the indium phosphide cap-layer thinning process, the effects of p-type doping concentration, surface states, and the corresponding surface recombination velocity（SRV） on the device sensitivity were analyzed. When the cap-layer thickness was reduced from 500 to 100 nm, the quantum efficiency at 0. 7 ??m increased from 6% to 41%, with the dark current density increasing from 0. 2 to 16. 7 nA/cm². The SRV significantly affected the device performance. As the SRV decreased from 3×10³ to 1×10³ cm/s, the peak specific detectivity（D^*） improved from 2. 31×10¹² to 3. 78×10¹² cm·Hz^1/2/W. By applying a surface passivation process, the dark current of the InGaAs photodetector was reduced, leading to an increase in the peak D^* from 2. 6×10¹² to 4. 1×10¹² cm·Hz^1/2/W. The results demonstrate that improving the surface passivation to lower the SRV is crucial for enhancing the performance of front-illuminated Vis-NIR InGaAs detectors.更多还原