  The Micromegas technology is one of the most successful MPGD concepts and
widely utilized in nuclear and particle physics experiments. Twenty years of
research and development rendered the technology sufficiently mature to be
selected as precision tracking detector for the New Small Wheel (NSW) upgrade
of the ATLAS Muon spectrometer. This will be the first large scale application
of Micromegas in one of the major LHC experiments. The studies on signal
formation in Micromegas focuses on the microscopic signal electron loss
mechanisms and the amplification processes in electron gas interaction. Based
on a model of detector parameter dependencies, these processes are scrutinized
in an iterating comparison between exper- imental results, theory prediction of
the macroscopic observables and process simulation on the microscopic level.
Utilizing the specialized detectors developed in the scope of this thesis as
well as refined simulation algorithms, an unprecedented level of accuracy in
the process description is reached, deepening the understanding of the
fundamental process in gaseous detectors. The second part is dedicated to the
challenges arising with the large scale Micro- megas production for the ATLAS
NSW. A selection of technological choices, are discussed alongside a final
report on two production related tasks addressing the detectors core
components: For the industrial production of resistive anode PCBs a detailed
quality control (QC) and quality assurance (QA) scheme as well as the therefore
required testing tools have been developed. In parallel the study on micromesh
parameter optimization and production feasibility resulted in the selection of
the proposed mesh by the NSW community. The successful completion of both tasks
were important milestones towards the construction of large size Micromegas
detectors clearing the path for NSW series production.
