Design and simulation of silicon detector cells with spiral ring electrode structures

Traditional pixel detectors are neatly arranged rectangular or square electrodes that cover almost the entire surface. Large electrode areas lead to high capacitance, and capacitance is the primary factor affecting detector noise. A large noise signal will reduce detector detection performance and the system S/N ratio. We have designed a spiral ring electrode silicon detector cell with n-type silicon bulk and systematically studied its electrical properties, including electric potential distribution, electric field distribution, electron concentration distribution, leakage current, full depletion voltage, and detector capacitance. It has been verified that the spiral ring electrode silicon detector has a smaller capacitance than the traditional detector and a smaller depletion voltage compared with the previously designed structures such as the inner circle broom-shaped structure. At the same time, high position resolution pixel detectors can be made by the array of these detector cells.