Back-Scattering Suppression for Broad-Spectral High-Absorption Silicon Extended Area Blackbody

TL;DR

This paper introduces a novel method to suppress backscattering in broad-spectral high-absorption silicon blackbodies, enhancing stability and emissivity for improved infrared calibration in extreme environments.

Contribution

It proposes a new backscattering suppression technique combined with femtosecond laser processing to create a high-emissivity, stable blackbody for precise infrared calibration.

Findings

Backscattering intensity and solid angle are significantly reduced.

The fabricated blackbody exhibits high emissivity and thermal stability.

Enhanced measurement accuracy in extreme environments.

Abstract

The stability and emissivity of the online calibration blackbody used in high-precision infrared remote sensing detectors in extreme environments are the primary limiting factors for their measurement accuracy. Due to the limitations of microstructure size effects, traditional calibration extended area blackbody cannot achieve an optimal balance between emissivity and stability, thus hindering further improvement in infrared remote sensing accuracy. This work proposes a new method that utilize suppressing near-field backscattering to control far-field reflectance. Specifically, through simultaneously reducing backscattering intensity and the backscattering solid angle, the reflectance is significantly reduced to an extremely low limit, which is validated through numerical simulations. Additionally, by combining the femtosecond laser self-convergent processing technique, the spontaneous energy negative feedback mechanism during femtosecond laser processing is utilized to achieve the fabrication of a high emissivity, thermally stable, mechanically stable, and highly uniform extended area blackbody. The blackbody fabricated using this technique can be applied for online calibration in various extreme environments, significantly improving measurement accuracy and service life.