Identify the cause of spatial detector non-uniformities

Identify which physical mechanism—spatial variations in silicon resistivity, local electric-field non-uniformities, partially depleted regions, or dead-layer-thickness variations—causes the observed position-dependent rise-time and energy-resolution variations in transmission silicon detectors.

Background

Off-beam alpha-source measurements show substantial position-dependent variations in rise time and energy resolution, particularly in the 1000 μm silicon detector. The similar spatial patterns suggest that both effects may share a common physical origin.

The paper lists several possible mechanisms, including variations in detector-material resistivity, local electric-field non-uniformities, partially depleted regions, and variations in dead-layer thickness. However, the measurements do not distinguish among these explanations, leaving the underlying cause unresolved.

References

Possible causes include spatial variations in the resistivity of the detector material, local non-uniformities in the electric field, partially depleted regions, or variations in dead-layer thickness. The present measurements do not allow distinguishing between them.

— Timing Challenges in Transmission Silicon Detectors for Light Ions  (2610.10127 - Tarrio et al., 7 Oct 2026) in Section Discussion