Testing pixel detectors with X-Rays. Measurements of the mini-MALTA prototype

Seminars

VBLHEP Scientific and Methodical Seminar #11

Date and Time: Thursday, 12 September 2019, at 11:00 AM

Venue: bld. 215, room 347, Veksler and Baldin Laboratory of High Energy Physics

Seminar topic: «Testing pixel detectors with X-Rays. Measurements of the mini-MALTA prototype»

Speaker: Kaloyan Metodiev (Oxford University, Oxford, UK)

Abstract:

This presentation outlines the results of investigations into the effects of radiation damage in the miniMALTA depleted monolithic pixel sensor prototype. MiniMALTA is a prototype test chip developed for the ATLAS ITk project, and contains a number of different pixel designs. These are the standard MALTA baseline layout, and two variant designs, one with an increased depth of the p-well, and one with a gap in the n-type layer. Measurements were carried out at Diamond Light Source using a micro-focus X-ray beam, which scanned across the surface of the device in 2 micrometers steps. This allowed the in-pixel photon response to be measured directly with high statistics. Six chips were tested: one that had suffered no radiation damage, one with 1e15 n/cm2 neutron damage, and three chips that had suffered proton damage from 27 MeV protons at the Birmingham cyclotron at 7e13 and 5e14 n/cm2. The effects of different damage levels on the three different pixel designs are discussed.