Sensor design for the ATLAS-pixel detector

The inner detector of the ATLAS experiment will contain three layers of pixel detectors. The first prototype of the sensor part will be an n+n-device in order to allow partial depleted operation after bulk inversion and a guard-ring scheme keeping the entire detector surface close to the electronic chip on ground potential. Further, a bias structure is introduced providing testability of the sensors before mounting them to the electronics. The design of the single pixel cell is the result of a detailed device simulation study.