The ZEUS micro-vertex detector

During the HERA luminosity shutdown period 2000/2001 the tracking system of the ZEUS experiment has been upgraded with a silicon micro-vertex detector. The barrel part of the detector consists of three layers of single-sided silicon strip detectors, while the forward section is composed of four wheels. In this report we shortly present the assembly procedure and in more details the test beam results on the spatial resolution of half modules. The first results of a cosmic ray test are presented and the radiation monitor system is described.