Speaker
Description
For the European Spallation Source (ESS), now under construction, a new generation of neutron detectors will be
required with groundbreaking properties in terms of 2D spatial resolution, time resolution, efficiency, rate capability, gamma discrimination and radiation hardness.
We propose to deposit a 10B containing semiconducting layer directly onto a pixel chip with charge-sensitive pixel input pads.
This layer is coated with a thin metal contact: by applying a certain potential to this contact, a bias field is created in
the semiconducting layer volume. Thermal neutrons, interacting with a 10B nucleus will cause a nuclear reaction resulting
in the emission of an alfa-particle and a recoil 7Li ion. These to charged energetic particles will strongly ionise the semiconductor
material. The bias field will separate electrons and holes, and with just a few ns life time of these charge carriers, sufficient
charge is induced onto the pixel input pads to activate the pixel circuitry.
With the available TimePix-3 chip, a high performance neutron detector would be feasible if a B containing compound can
be created and deposited with charge carrier properties meeting specific requirements. These properties should not change
after the absorption of a certain amount of neutrons. The TimePix-3 chip itself is shielded from neutrons by the
active 10B contains layer. As layer material, BC, BNC, B4C are potential candidates.
