Characteristics of the ALICE Silicon Drift Detector

A Rashevsky,V Bonvicini,P Burger,P Cerello,E Crescio,P Giubellino,R Hernández-Montoya,A Kolojvari,L.M Montaño,D Nouais,C Piemonte,F Tosello,A Vacchi,R Wheadon

doi:10.1016/s0168-9002(00)01189-x

Abstract

A Silicon Drift Detector (SDD) with an active area of 7.0×7.5 cm 2 has been designed, produced and tested for the ALICE Inner Tracking System. The development of the SDD has been focused on the capability of the detector to work without an external support to the integrated high-voltage divider. Several features have been implemented in the design in order to increase the robustness and the long-term electrical stability of the detector. One of the prototypes has been tested in a pion beam at the CERN SPS. Preliminary results on the position resolution are given.

Highlights

A Silicon Drift Detector (SDD) with an active area of 7.0 × 7.5 cm2 has been designed, produced and tested for the ALICE Inner Tracking System
A dedicated study [3] demonstrated that NTD silicon was suitable for the production of SDDs, providing doping fluctuations below 2% (r.m.s.) with maximum variations of about 6%
The detector has a bi-directional structure, where electrons drift from the central p+ cathode towards two linear arrays of n+ anodes. It has a hexagonal shape with a rectangular sensitive area that allows to minimise the overlapping of adjacent SDDs in the ladder assembly

Summary

Introduction

A Silicon Drift Detector (SDD) with an active area of 7.0 × 7.5 cm2 has been designed, produced and tested for the ALICE Inner Tracking System. The detector has a bi-directional structure, where electrons drift from the central p+ cathode towards two linear arrays of n+ anodes. The detector is planned to work at a potential difference of about 8 V between adjacent drift cathodes which corresponds to a drift field of 670 V /cm.

Results

Conclusion