A High-Granularity Timing Detector (HGTD), based on Low-Gain Avalanche Detector (LGAD) technology, is proposed for the ATLAS Phase-II upgrade.
In this contribution, we present new developments in the production of LGAD by NDL (Novel Device Laboratory, Beijing) and IHEP. NDL has delivered three batches of LGAD prototype sensors at the beginning of 2019. These sensors are fabricated with 30um high resistivity epitaxial silicon layer. Time resolution of 𝜎 ~ 30 ps can be achieved with these sensors in both beta test and electron beam test before irradiation.
We will also show the collected charge and timing performances of IHEP-NDL LGAD sensors after proton irradiation up to 4.5 E15 neq/cm^2 or after X-ray irradiation up to 3MGy. A variety of design strategies to improve radiation hardness, including changing the guard ring design, varying the resistance of the epitaxial silicon layer and varying gain layer doping profile of LGAD sensors, will be discussed.
|Submission declaration||Original and unpublished|