The silicon sensors for the Compact Muon Solenoid tracker—design and qualification procedure

Abstract

The Compact Muon Solenoid (CMS) is one of the experiments at the Large Hadron Collider (LHC) under construction at CERN. Its inner tracking system consist of the world largest Silicon Strip Tracker (SST). In total it implements 24244 silicon sensors covering an area of 206 m 2 . To construct a large system of this size and ensure its functionality for the full lifetime of ten years under LHC condition, the CMS collaboration developed an elaborate design and a detailed quality assurance program. This paper describes the strategy and shows first results on sensor qualification.

CMS tracking performance results from early LHC operation

“…Similarly, the coolant temperature was set at 4-6 • C, the same as in the CRAFT study. This meant that the p + on n sensors [18] were approximately at room temperature.…”

The LHCb Detector at the LHC

“…A copper mesh backplane provides a solid ground connection and shielding against pick-up noise. The small strip width was required to keep the strip capacitance of the cable small, but led to an unacceptably low production yield for fault 11 The sensors are identical in design to the OB2 sensors used in the Outer Barrel of the CMS Silicon Tracker [56] and were produced by Hamamatsu Photonics K.K., Hamamatsu City, Japan. 12 The Kapton interconnect cables were produced by Dyconex AG, Bassersdorf, Switzerland.…”

LHCb Silicon Tracker Operations and Performance

“…It consists of four layers arranged into two half stations separated by 30 cm along the beam axis. The detector is constructed using 500 µm thick p-on-n type sensors of the same design as used in the CMS barrel [3]. The readout pitch is 183 µm.…”