# Diamond-Like Carbon for the Fast Timing MPGD

## TL;DR

This paper explores the development of a fast timing Micro-Pattern Gaseous Detector using Diamond-Like Carbon films, aiming to improve timing resolution for high-energy physics experiments.

## Contribution

It introduces a new detector concept, the Fast Timing MPGD, utilizing DLC films with improved adhesion and uniformity, addressing previous production challenges.

## Key findings

- Initial promising results with DLC-based detectors
- Identification of adhesion and stress issues in DLC films
- Development of improved DLC production techniques

## Abstract

The present generation of Micro-Pattern Gaseous Detectors (MPGDs) are radiation hard detectors, capable of detecting efficiently particle rates of several MHz/cm$^2$ , while exhibiting good spatial resolution ($\leq$ 50 $\mu$m) and modest time resolution of 5-10 ns, which satisfies the current generation of experiments (High Luminosity LHC upgrades of CMS and ATLAS) but it is not sufficient for bunch crossing identification of fast timing systems at FCC- hh. Thanks to the application of thin resistive films such as Diamond-Like Carbon (DLC) a new detector concept was conceived: Fast Timing MPGD (FTM). In the FTM the drift volume of the detector has been divided in several layers each with their own amplification structure. The use of resistive electrodes makes the entire structure transparent for electrical signals. After some first initial encouraging results, progress has been slowed down due to problems with the wet-etching of DLC-coated polyimide foils. To solve these problems a more in-depth knowledge of the internal stress of the DLC together with the DLC-polyimide adhesion is required. We will report on the production of DLC films produced in Italy with Ion Beam Sputtering and Pulsed Laser Deposition, where we are searching to improve the adhesion of the thin DLC films, combined with a very high uniformity of the resistivity values.