# Optical Properties and Thermal Stability of Ag-In-Cu Film on Aluminum Alloy Substrate Deposited by Magnetron Sputtering

## TL;DR

This study explores how to create highly reflective and thermally stable silver-indium-copper films on aluminum for aerospace and military uses.

## Contribution

The paper introduces a method to optimize AgInCu film composition and deposition parameters for enhanced reflectivity and thermal stability.

## Key findings

- Higher copper content improves thermal stability but reduces reflectivity.
- Optimal deposition at 30 W for 2 min achieved 99.8% near-infrared reflectivity.
- AgInCu films show promise for next-generation optical applications.

## Abstract

High-reflectivity metallic films on aluminum substrates are crucial in advanced aerospace and military applications due to their excellent reflectivity and workability. In order to further improve the reflectivity and thermal stability of films, this study investigated the deposition of AgInCux (x = 1, 3, and 5 wt.%) films on Al 6061 alloy substrates using magnetron sputtering, exploring the impact of deposition parameters and composition on their optical properties and thermal stability. Increased copper content improved thermal stability, while it compromised reflectivity. Additionally, increasing deposition power and time initially enhanced reflectivity, but beyond an optimal point, it decreased. Therefore, the AgInCu films deposited at 30 W for 2 min exhibited the highest reflectivity of 99.8% in the near-infrared range, making them promising candidates for reflective films in next-generation optical applications.