Characterization of single layer anti-reflective coatings for bolometer-based rare event searches

TL;DR

This paper investigates the fabrication and characterization of single-layer anti-reflective coatings on Ge and Si wafers to enhance photon detection in bolometer-based rare event searches, aiming to improve background reduction techniques.

Contribution

It provides the first detailed analysis of SiO₂, HfO₂, and TiO₂ coatings on Ge and Si wafers for bolometric applications, focusing on their optical properties at various angles.

Findings

Coatings significantly reduce reflectance at multiple angles.

HfO₂ and TiO₂ coatings show promising optical performance.

Room temperature characterization confirms potential for improved light detection.

Abstract

Combining analysis from phonon signals and photon signals is a powerful technique for reducing backgrounds in bolometer-based rare event searches. Anti-reflective coatings can significantly increase the performance of the secondary light-sensing bolometer in these experiments. As a first step toward these improvements, coatings of SiO$_2$, HfO$_2$, and TiO$_2$ on Ge and Si wafers were fabricated and characterized at room temperature and multiple angles of incidence.