Characteristics Of Silicon Drift Detector

In recent years,the X-ray pulsar navigation system has become a research hotspot in the world.High-speed X-ray detector is an important device in the pulsar navigation system,and the performance of High-speed X-ray detector directly determines the accuracy of pulsar navigation system.In various X-ray detectors,silicon drift detectors play an important role in deep space exploration and pulsar navigation system due to their good energy resolution,time resolution and high signal-to-noise ratio.Therefore,this paper takes the silicon drift detector as the research object,simulates the electrical characteristics of the silicon drift detector,and provides theoretical support for the project to develop high-performance silicon drift detectorsBased on the simulation software of Sentaurus TCAD,a three-dimensional model of the silicon drift detector is established to simulate the electric potential,electric field,electron density,voltage divider current,leakage current,capacitance and depletion voltage of the silicon drift detector,and the main conclusions are as follows:(1)We simulate the structure of circular ring and quadrilateral silicon drift detector,conclude that the electric potential distribution inside the circular ring silicon drift detector has a better symmetry,and the good symmetry of the circular structure is verified by the distribution of electric field and electron concentration inside the detector,and a good drift channel can be formed inside the detector.(2)We simulate the current on the voltage divider of the circular ring silicon drift detector,gradually increased the reverse bias in the outermost drift ring,and obtain the I-V characteristic curves of the current and external bias at different voltage divider widths.By comparison,the current on the divider increases with the width increasing,and the punch through voltage between the drift rings decreases with the width increasing.(3)For circular silicon drift detector run out of saturated capacitance and leakage current and voltage in the simulation,the probe’s outer drift gradually increasing reverse voltage detector I-V and C-V characteristic curve,get detector depletion voltage is about-140 V,detector is obtained by the I-V characteristic curve of leakage current of 2.4 ×10-9 A,detector is obtained by C-V characteristic curve of saturated capacitance is about 80 fF.