Eur. Phys. J. A (2015) 51: 141
https://doi.org/10.1140/epja/i2015-15141-9

Special Article - Tools for Experiment and Theory

Characterization of different surface passivation routes applied to a planar HPGe detector

¹ Department of Physics and Astronomy “G. Galilei”, University of Padova, Via Marzolo 8, 35121, Padova (PD), Italy
² Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020, Legnaro (PD), Italy
³ Institut für Kernphysik, Universität zu Köln, Zülpicher Straße 77, D-50937, Köln, Germany
⁴ Department of Physics and Astronomy, University of Catania, Via Santa Sofia 64, 95123, Catania (CT), Italy

^* e-mail: maggioni@lnl.infn.it

Received: 25 March 2015
Revised: 24 September 2015
Accepted: 4 October 2015
Published online: 3 November 2015

Abstract

The effects of different passivation methods applied to the same planar high-purity germanium gamma radiation detector have been studied. By means of the scanning with a low-energy collimated gamma source, it has been found that the surface passivation gives rise to a dead layer below the intrinsic Ge surface, whose thickness and distribution are strongly dependent on the passivation type. Measured bulk detector properties like the peak-to-Compton ratio and efficiency have shown a dependence on the passivation and an influence of the passivation type on the depletion voltage, whilst the optimal energy resolution has been the same for all the passivations.