2017-LS-173 - Optical Profilometer

The SFU High Energy Physics group is participating in the construction and testing of the Inner Tracker (ITk) upgrade for the ATLAS detector at the Large Hadron Collider at CERN. ATLAS (www.atlas.ch) is a particle physics experiment designed to detect new particles and investigate the fundamental forces that shape the sub-atomic world. The experiment is currently in operation and produces physics results. Due to the harsh radiation environment, ATLAS plans to replace and simultaneously upgrade their innermost detectors which are exposed to the most radiation.
 
The ATLAS collaboration involves more than 3000 scientists from 183 institutions in 38 countries. Canada's contribution to the ATLAS experiment is ATLAS-Canada. They are responsible for constructing a large number of components for the new ATLAS silicon microstrip tracker to be installed in 2024. The sensors will be in a wheel format composed of multiple trapezoidal petals. Each petal will contain nine sensors arranged in six rings. The sensors will be tested to ensure they meet stringent requirements before constructing the petals. As part of ATLAS-Canada, the group at SFU is responsible for constructing many of these petals before 2023.
 
One of the requirements is measured by doing a continuous profile measurement over the entire sensor surface. The bowing of sensors is monitored to ensure that their positions conform to the acceptable tolerances. The testing also ensures the sensors are free from physical defects, surface scratches as well as have clean, straight cut edges without chipping. SFU seeks a profilometer to be used for measuring silicon sensors with precision of the order of a micron for this testing.