May 24 – 28, 2021
America/Vancouver timezone

Surface passivation of single photon avalanche diodes for enhanced sensitivity in the vacuum ultraviolet range for liquid noble gas experiments

May 27, 2021, 8:24 AM
Parallel session talk Sensors: Photo-detectors Sensors: Photo-detectors


Frédéric Vachon (University of Sherbrooke)


The next Enriched Xenon Observatory (nEXO) is an experiment dedicated to the fundamental study of neutrinos. It searches for new physics beyond the Standard Model through the observation of the neutrinoless double-beta decay in xenon-136. The design of the nEXO time projection chamber includes Silicon Photmultipliers (SiPM) as key components to detect the scintillation light at 175nm, where a photon detection efficiency greater than 15 % is required.

This talk reviews the challenges of VUV direct detection in silicon-based detectors. It presents the prototype of Sherbrooke’s single photon avalanche diodes on which a highly doped and very thin passivation layer is applied in order to prevent surface dark electron injection while improving the collection of VUV photogenerated carriers. It overviews the fabrication process challenges with suggestions for a second revision. The impact on the detector’s dark noise and photon detection efficiency is also presented.

TIPP2020 abstract resubmission? No, this is an entirely new submission.

Primary author

Frédéric Vachon (University of Sherbrooke)


Samuel Parent (University of Sherbrooke) Craig S Tindall (Lawrence Berkeley National Laboratory) Henri Dautet (University of Sherbrooke) Fabrice Retiere (TRIUMF) Jean-Francois Pratte (University of Sherbrooke) Serge Charlebois (University of Sherbrooke.)

Presentation materials