Simulation Results from Double-Sided 3D Detectors

A new "double sided" 3D solid-state detector structure, intended to simplify the 3D fabrication process, is proposed. In this structure, electrode columns of different doping types are etched from opposite sides of the substrate, with neither set of columns passing through the full substrate thickness. Simulations of the electrostatic and charge collection behavior in this structure have been made with ISE-TCAD to investigate its advantages and disadvantages and optimize its design. The device was shown to have a low depletion voltage, a short charge collection time, and a similar electric field distribution to a conventional 3D detector. However, near the front and back surfaces of the structure the electric field is lower and the charge collection time is longer. It is concluded that using this "double sided" 3D structure is not expected to significantly alter the device's behavior, and has advantages for fabrication.