Design and simulation of a novel concentric silicon drift detector with equal width divider resistor chain and floating cathodes

Enabling the traditional concentric silicon drift detector (CSDD) does not need an external voltage divider in the application; hence, a novel CSDD structure is proposed in this paper, in which resistor chains of equal width are deposited equally between the cathode rings and come in contact with the cathode rings. The new CSDD can achieve voltage division automatically and only needs to bias the voltage on the cathodes of the innermost ring and the outermost ring. In addition, floating cathodes were designed between the cathodes to obtain a nearly straight line drift channel and to reduce the low electric field area near the surface. The electrical properties of three types of floating cathodes (called floating cathodes of a single-ring, floating cathodes of a double-ring, and floating cathodes of a four-ring) were simulated and compared using the technology computer aided design tool. Under the field effect between the floating cathodes and the bulk, the electric field near the surface increased substantially. Moreover, the electric field near the surface of the CSDD with the floating cathodes of a double-ring changes the most uniformly so that the drift path is the straightest.