10th International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices

Name: 10th International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices
Start: 2014-10-08T08:00:00+02:00
End: 2014-10-10T18:00:00+02:00
Location: Firenze, Italy

8–10 Oct 2014

Firenze, Italy

Europe/Zurich timezone

Support

mara.bruzzi@unifi.it

Modeling and simulation of charge collection properties for 3D-Trench electrode detector

9 Oct 2014, 10:00

20m

Firenze, Italy

Dipartimento di Fisica ed Astronomia Universita' di Firenze Largo E. Fermi 2, Firenze, Italy

3D Detectors

Zheng Li (Xiangtan University)

3D-trench electrode detector with square geometry was simulated in this paper. Charge collection of 3D-trench electrode detector was simulated using the full 3D device simulation. The induced current and collected charge caused by drifting carriers, generated by a minimum ionizing particle (MIP) incident through the detector, have been modeled and calculated. The results indicate that the total collected charge in irradiated detector change with various particle incident positions and radiation fluence. In addition, we have estimated the average total collected charge generated by the MIP at a random incident position of a 3D-trench electrode detector.

Summary

In this paper, the effect of charge collection of a square shape 3D-trench electrode detector (Fig.1a) was investigated. For a non-irradiated detector, the total collected charge is independent of the particle incident position (Fig. 2a). However, as shown in Fig. 2b, for an irradiated detector, the total collected charge changes with various incident position (at r = ri in Fig.1b). This is due to the fact that the probability of hole trapping and electron trapping will change with the particle incident position, which affects the composition of electron and hole contributions to the induced current and therefore the total collected charge. The collected charge will also be affected by the weighting field profile and electric field profile. The induced current and total collected charge reduce with increasing fluence, as the trapping probability increases linearly with radiation fluence. Fig.3a shows the collected charge caused by a MIP incident at the middle point between two electrodes, with a bias voltage of 100 V. Fig.3b is the average collected charge by a MIP at a random incident position of a 3D-trench electrode detector, at various bias voltages over full depletion voltage. We note that the collected charge increases slightly with bias voltage, and for the detector with same radiation fluence and bias voltage, the average collected charge is usually not equal to the collected charge caused by a MIP incident at the middle point between two electrodes.
Fig. 1.a) Structure of the simulated rectangular 3D-trench electrode detector;
b) Schematic view of a MIP incident in the 3D-trench electrode detector. a) b)
Fig. 2. Collected charge as a function of MIP incident position, a) with no irradiation, V=100 V; b) with the fluence of 1x1016 neq/cm2, V=100 V. Fig. 3. a) Collected charge as a function of fluence, MIP incident position rI=32 μm, V=100 V; b) average collected charge as a function of fluence, with various bias voltage.