Speaker
Description
on behalf of the ATLAS ITk strip sensor working group.
For the Phase-II Upgrade of the ATLAS detector, a new, all-silicon
tracker will be constructed in order to cope with the increased track den-
sity and radiation level of the High Luminosity Large Hadron Collider.
While silicon strip sensors are designed to minimise the fraction of
dead material and maximise the active area of a sensor, concessions must
be made to the requirements of operating a sensor in a particle physics
detector. Sensor geometry features like the punch-through protection de-
viate from the standard sensor architecture and thereby affect the charge
collection in that area.
In order to study the signal collection of silicon strip sensors over their
punch-through-protection area, ATLAS silicon strip sensors were scanned
with a micro-focused X-ray beam at the Diamond Light Source. Due to
the highly focused X-ray beam (2 × 3 μm) and the short average path
length of an electron after interaction with an X-ray photon (≤ 2 μm),
local signal collection in different sensor areas can be studied with high
resolution.
This study presents results of highly detailed 2D-scans of the punch-
through protection region of ATLAS silicon micro-strip sensors, showing
how far the strip signal collection area extends toward the bias ring and
how the region is affected by radiation damage.
