High performance band-gap engineered nanowires-based SWIR photodetectors

Overview

The proposed technology is a high-performance short-wave infrared (SWIR) photodetector utilizing GaAsSb nanowires with engineered bandgap profiles. These nanowires are grown on a monolayer graphene/SiO₂/Si substrate, forming a core-shell PIN junction that enhances absorption and carrier separation. This innovative design suppresses axial hole transport and promotes efficient radial carrier extraction, enabling detection in the deeper SWIR regime. The technology has demonstrated ultra-high responsivity (2000 A/W) and detectivity (10¹⁴ Jones) at 1500 nm, making it suitable for advanced infrared sensing applications.

Technical specifications

• Materials and Design: Uses GaAsSb nanowires with varying Sb composition in a Te-doped n-type axial layer.
• Growth Technique: Ga-assisted molecular beam epitaxy (MBE) for sharp interfaces and minimal defects.
• Device Performance: Achieves responsivity of 2000 A/W and detectivity of 10¹⁴ Jones at 1500 nm.
• Fabrication: Simple, scalable, and cost-effective due to the nanowire forest growth method, avoiding complex lithography.
• Applications: Suitable for flexible SWIR photodetectors and next-generation infrared sensing platforms.

Technology readiness level

The technology is currently at TRL 4, having achieved lab-scale validation with successful demonstration of high performance at room temperature. Future validation plans include further development and characterization to extend operational wavelengths up to 1.7 µm and enhance device performance metrics.