Development of high-sensitive silicon image sensor in near-infrared region by plasmonic transmission with large angle

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K18984
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 30:Applied physics and engineering and related fields
• Research Institution: Shizuoka University
• Principal Investigator: Ono Atsushi 静岡大学, 電子工学研究所, 教授 (20435639)
• Project Period (FY): 2022-06-30 – 2024-03-31
• Keywords: 表面プラズモン / イメージセンサ / 回折格子 / 近赤外

Outline of Final Research Achievements

This research challenges to bring the technological innovation that is significant improvement of silicon image sensors in near-infrared region, which is recently attracted in automatic driving technology, communication technology, and bioinstrumentation technology. As one of the goal in this research project, we aim to dramatically improve the sensitivity so that the silicon absorption efficiency at 940 nm is more than 50%, which is equivalent to that in the visible range. By considering a back-illuminated silicon image sensor, we proposed photon confinement in a silicon absorption layer by plasmonic diffraction. We clarified by the simulation that the absorption efficiency is achieved to be 53.3% at a wavelength of 940 nm.

Free Research Field

応用光学

Academic Significance and Societal Importance of the Research Achievements

本研究は，表面プラズモン共鳴よりもわずかに短波長側の回折条件にて構造設計することにより，90度近い大きな回折角度と50%近い高い回折効率のプラズモニック回折が起きることを明らかにしたものであり，準表面プラズモン共鳴という新たな概念を提唱した．
本概念をシリコンイメージセンサの近赤外感度向上技術に応用することにより，TOFセンサなどの低照度化，低消費電力化，高解像度化，高速化など現行に対して革新的技術をもたらすことが期待される．