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arXiv · 1912.01902

Improving the Spatial Resolution of Silicon Pixel Detectors through Sub-pixel Cross-coupling

Sinuo Zhang·David-Leon Pohl·Tomasz Hemperek·Jochen Dingfelder
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Abstract

We present a concept to improve the spatial resolution of silicon pixel-detectors via the implementation of a sub-pixel cross-coupling, which introduces directional charge sharing between pixels. The charge-collection electrode is segmented into sub-pixels and each sub-pixel is coupled to the closest sub-pixel of the neighboring pixel. Such coupling schema is evaluated for a model sensor design with $50 \mu m \times 50 \mu m$ pixels and AC-coupled sub-pixels. A first-order SPICE simulation is used, to determine feasible coupling strengths and assess the influence on the charge-collection efficiency. The impact of the coupling strength on spatial resolution is studied with a dedicated simulation, taking into account charge-cloud evolution, energy-loss straggling, electronic noise, and the charge detection-threshold. Using simplifying assumptions, such as perpendicular tracks and no gaps between charge-collection electrodes, an improvement of the spatial resolution by up to approximately $30\%$ is obtained in comparison to the standard planar pixel layout.

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Sinuo Zhang, David-Leon Pohl, Tomasz Hemperek, Jochen Dingfelder. 2019-12-04. Improving the Spatial Resolution of Silicon Pixel Detectors through Sub-pixel Cross-coupling. https://arxiv.org/abs/1912.01902

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