Thin film and surface preparation chamber for the low energy muons spectrometer

TL;DR

This paper details the design and construction of a high-vacuum thin film preparation chamber equipped with multiple deposition tools, enabling high-quality film production and direct transfer to a low energy muons spectrometer for advanced material analysis.

Contribution

It introduces a specialized chamber capable of producing large-area thin films with high uniformity, integrated with transfer capabilities for LE-$bc$SR measurements, advancing experimental material science methods.

Findings

Successful fabrication of uniform CuPc and TbPc$_2$ films

First LE-$bc$SR measurements on these films

Chamber design supports future in-vacuum transfer to characterization facilities

Abstract

We have designed and constructed a thin film preparation chamber with base pressure of $<2 \times 10^{-9}$~mbar. Currently, the chamber is equipped with two large area evaporators (a molecular evaporator and an electron-beam evaporator), an ion sputtering gun, a thickness monitor and a substrate heater. It is designed such that it can handle large area thin film samples with a future possibility to transfer them in vacuum directly to the low energy muons (LEM) spectrometer or to other advanced characterization facilities in the Quantum Matter and Materials Center (QMMC) which will be constructed in 2024. Initial commissioning of the chamber resulted in high quality, large area and uniform molecular films of CuPc and TbPc$_2$ on various substrate materials. We present first results from low energy $\mu$SR (LE-$\mu$SR) measurements on these films.