The state of art of -RWELL technology

The mu-RWELL is a single-amplification stage resistive Micro-Pattern Gaseous Detector (MPGD). The detector amplification element is realized with a single copper-clad polyimide foil micro-patterned with a blind hole (well) matrix and embedded in the readout PCB through a thin Diamond-Like-Carbon (DLC) sputtered resistive film. The introduction of the resistive layer, suppressing the transition from streamer to spark, allows to achieve large gains (=104) with a single amplification stage, while partially reducing the capability to stand high particle fluxes. The simplest resistive layout, designed for low-rate applications, is based on a single-resistive layer with edge grounding. At high particle fluxes this layout suffers of a non-uniform response. In order to get rid of such a limitation different current evacuation geometries have been designed. In this work we report the study of the performance of several high rate resistive layouts tested at the CERN H8-SpS and PSI pM1 beam test facilities and with a high intensity 5.9 keV X-ray tube. These layouts fulfill the requirements for the detectors upgrades at the HL-LHC and for the experiments at the next generation colliders FCC-ee/hh and CepC.The possibility to realise the detector on flexible elements opens the way to use the technology for non-planar geometry such as the instrumentation of the Inner Tracker at future Charm-Tau factories. In addition, it must be stressed that the mu-RWELL device can be manufactured with full sequential-build-up technology, thus allowing a straightforward technology transfer of the manufacturing process to the industry.