This paper demonstrates the novel approach of sub-micron-thick InGaAs broadband photodetectors (PDs) designed for high-resolution imaging from the visible to short-wavelength infrared (SWIR) spectrum. Conventional approaches encounter challenges such as low resolution and crosstalk issues caused by a thick absorption layer (AL). Therefore, we propose a guided-mode resonance (GMR) structure to enhance the quantum efficiency (QE) of the InGaAs PDs in the SWIR region with only sub-micron-thick AL. The TiO_x/Au-based GMR structure compensates for the reduced AL thickness, achieving a remarkably high QE (>70%) from 400 to 1700 nm with only a 0.98 μm AL InGaAs PD (defined as 1 μm AL PD). This represents a reduction in thickness by at least 2.5 times compared to previous results while maintaining a high QE. Furthermore, the rapid transit time is highly expected to result in decreased electrical crosstalk. The effectiveness of the GMR structure is evident in its ability to sustain QE even with a reduced AL thickness, simultaneously enhancing the transit time. This breakthrough offers a viable solution for high-resolution and low-noise broadband image sensors.

本文展示了亚微米厚的 InGaAs 宽带光电探测器 （PD） 的新方法，该方法设计用于从可见光到短波长红外 （SWIR） 光谱的高分辨率成像。传统方法会遇到一些挑战，例如低分辨率和由厚吸收层 （AL） 引起的串扰问题。因此，我们提出了一种导模共振 （GMR） 结构，以提高 InGaAs PDs 在 SWIR 区域中的量子效率 （QE），而 AL 只有亚微米厚。基于 TiO_x/Au 的 GMR 结构补偿了 AL 厚度的减少，仅使用 0.98 μm AL InGaAs PD（定义为 1 μm AL PD），即可在 400 至 1700 nm 范围内实现非常高的 QE （>70%）。这意味着与以前的结果相比，厚度至少减少了 2.5 倍，同时保持了较高的 QE。此外，人们预计快速传输时间将减少电串扰。GMR 结构的有效性显而易见，即使在 AL 厚度减小的情况下，它也能维持 QE，同时增加传输时间。这一突破为高分辨率和低噪声宽带图像传感器提供了一种可行的解决方案。