First test beam results on DEPFET pixels for the ILC

By incorporating a field effect transistor into a fully depleted sensor substrate the DEPFET sensor combines radiation detection and amplification in each pixel, resulting in very low noise and high spatial resolution. This makes DEPFET sensors a favorable technology for the vertex detector at the planned International Linear Collider (ILC). A prototype system with fast steering chips, a current-based readout chip and a 64×12864×128 pixels DEPFET matrix has been built and was operated successfully in the DESY test beam. First results of the studies on two different DEPFET design options are presented in this paper.