Optimization of light trapping micro-hole structure for high-speed high-efficiency silicon photodiodes

TL;DR

This paper presents an optimization of micro-hole structures in silicon photodiodes to enhance light trapping, resulting in improved efficiency and uniformity across a broad wavelength range.

Contribution

It introduces a novel micro-hole design with controlled disorder and shape to optimize light trapping and quantum efficiency in high-speed silicon photodiodes.

Findings

Lateral modes are key to effective light trapping.

Small disorder improves uniformity of quantum efficiency.

Cone-shaped holes enhance light trapping efficiency.

Abstract

We optimized micro-holes in a thin slab for fast Si photodetectors at wavelength 800-950nm. Lateral modes are shown to be responsible for the effective light trapping. Small disorder and cone hole shapes helped achieve uniform quantum efficiency in a wide wavelength range.