A study of scattering structures for high sensitive near-infrared pixels

As the demands for CMOS Image Sensors in the applications such as medical imaging, security systems, and Advanced Driver Assistance Systems (ADAS) are increasing, high sensitivity in the near-infrared (NIR) wavelength is more important. In addition, pixel pitch is also being miniaturized for high-resolution NIR sensors and single-chip integration. In this paper, we study the in-pixel Scattering Trench (IST) as the scattering structure for enhancing NIR sensitivity in the sub-micron pixel. By comparison between conventional and suggested pixels with IST, it was confirmed that the NIR sensitivity improved by up to 154.7% at wavelengths of 850nm in the 1.0$\mu$m pixel.