Comprehensive modeling of silicon microstrip detectors

Abstract

ances, leakaae currents, etc.In this work, the application of numerical device simulation to the analysis of high resistivity silicon microstrip detectors is illustrated. The analysis of DC, AC and transient responses of a single-sided, Dc-coupled detector has been carried out, providing results in good agreement with experimental data. In particular, transient-mode simulation has been exploited to investigate the collection of charges generated by ionizing particles. To this purpose, an additional generation term has been incorporated into the transport equations; the motion of impact-generated carriers under the combined action of ohmic and diffusive forces is hence accounted for. Application to radiation tolerance studies is also introduced.In this paper, the application of numerical device simulation to the analysis of high-resistivity, single-sided silicon microstrip detectors is illustrated; besides carrying out the complete characterization of equivalent-circuit parameters, we present a novel approach to the simulation of sensors' active behavior, i.e., to the analysis of charge collection phenomena. This has been made possible by means of a suitably "customized" transient simulation technique. Details on the actual characteristics of the simulation tool are presented in sect. 2, with particular emphasis on the features introduced in order to model the charge-collection dynamics. .Simulation results are presented in Sect. 3: here, radiation influence over a couple of important detector-design parameters (namely, the depletion voltage and the strip capacitance) has been evaluated by properly adjusting the oxide charge and the effective doping concentration. Sect. 4 below is more specifically devoted to the analysis of the charge collection mechanisms: the timedomain sensor response to a particle crossing the detector is simulated, from which the spatial resolution is estimated.

Pulse Pileup Analysis for a Double-Sided Silicon Strip Detector Using Variable Pulse Shapes

“…Figures 11 (a), (b) and (c) compare the energy histograms in a single electrode under three photon fluxes against one with no pileup. The bimodal characteristic, i.e., with two peaks at the two ends of the spectrum, has been observed from both experimental and simulation results [32][33][34]. Figure 11 (d) compares the corresponding histograms with pileup in the 20-40 keV range.…”

Physical modeling of silicon microstrip detectors: influence of the electrode geometry on critical electric fields

“…The program solves the semiconductor transport equations (in the drift-diffusion approximation) over a discretized two-dimensional domain, and it has been customized for the analysis of radiation detectors. In particular, features relevant to this goal include: i) a transient-simulation mode dedicated to the charge-collection analysis [5], and, ii) a physically accurate model of bulk radiation damage, based on multiple deep-level traps [6]. Moreover, thanks to the discretization scheme adopted, the tool features a high flexibility in the geometrical description of the simulation domain: this makes it possible to quickly analyze responses coming from different device designs, and to correlate the actual device shape to its electrical characteristics.…”

A comprehensive analysis of low-resistivity silicon radiation detectors

“…In particular, the program solves the semiconductor transport equations (in the drift-diffusion approximation) over a discretized two-dimensional domain. Features relevant to our goals include: i) the description of the charge dynamically generated by the ionizing particle along its path [4], and, ii) radiation-induced deep-level trap model [5].…”