Silicon detector developments for CMS

At the end of 1999, the CMS collaboration decided for a tracking system based entirely on silicon detectors. The all-silicon tracker for CMS is a major challenge in terms of performance, scale of the devices and severity of the radiation environment. To fulfill all the requirements, a large program of study and development in the field of silicon strip detectors has been carried out. The characteristics of silicon microstrip detectors were measured for different strip pitches and various strip implant and metal widths. Devices were investigated before and after irradiation. The optimization of the design parameters and choice of substrate resistivity and crystal orientation are reviewed.