Speaker
Description
Future experiments in particle physics foresee few-micrometer single-point position resolution in their vertex detectors, motivated by e.g. b/light-quark-tagging capabilities. Silicon is today's material of choice for high-precision detectors and offers a high grade of engineering possibilities. Instead of scaling down pitch sizes, which comes at a high price for an increased number of channels, our new sensor concept seeks to improve the position resolution by increasing the lateral size of the charge distribution already during the drift in the sensor material. To this end, it is necessary to carefully engineer the electric field in the bulk of this so-called enhanced lateral drift (ELAD) sensor. This is achieved by implants deep inside the bulk which allows for a modification of the charge carriers' drift paths.
In order to engineer the sensor bulk, we chose to combine epitaxial growth with ion beam implantation in an alternating approach. Test samples are analysed with spreading resistance profiling (SRP) and electrochemical capacitance-voltage (ECV) profiling and are compared to TCAD optimisation studies.
Results of the ECV and SRP measurements are presented and discussed. The feasibility of bulk engineering through the combination of epitaxial growth and ion beam implantation is discussed. Additionally, we demonstrate the potential of ELAD sensors, which make use of bulk engineering, in comparison to conventional planar hybrids based on test beam simulation studies.
