Micro-channel Cooling for Silicon Detectors

Silicon tracking detectors employed in high-energy physics are located very close to the interactionpoints of the colliding particle beams. The high energetic radiation emerging from the interactioninduces defects into the silicon, downgrading the efficiency to collect the charges created by passingparticles and increasing the noise while data taking. Cooling the sensors to low temperatures canhelp to prevent defects and maintain a high efficiency and lower noise level.In order to maximize the LHC’s discovery potential, the collider and its detectors will be upgraded toa higher luminosity around 2024. The conditions inside the detector will become harsher demandingthat the technology must adapt to the new situation.Radiation damage is already an issue in the current ATLAS detector and therefore a huge number ofparameters are constantly monitored and evaluated to ensure optimal operation. To provide the bestpossible settings the behavior of the sensors inside the ATLAS Inner Detector is predicted usingsimulations. In this work several parameters in the simulation including the depletion voltage andthe crosstalk between sensor strips of the SCT detector are analyzed and compared with data.The main part of this work concerns the investigation of a novel cooling system based on micro-channels etched into silicon in a generic research and development project at DESY and IMB-CNM.A channel layout is designed providing a homogeneous flow distribution across a large surfacearea and tested in a computational fluid simulation before its production. Two different fabricationtechniques, anodic and eutectic bonding, are used to test prototypes with differing mechanical andthermal properties. Hydromechanical and thermal measurements are performed to fully characterizethe flow inside the device and the thermal properties of the prototype in air and in a vacuum. Thethermal behavior is analyzed by means of local measurements with thermal resistors and infraredcameras. A test facility is developed and constructed in order to realize the measurements. Theresults of the simulations and the experimentally gained results are compared and contrasted