Speaker
Description
The ATLAS experiment will be replacing the current inner detector with the Inner Tracker (ITk) to accommodate the increased occupancy and radiation levels anticipated at the High-Luminosity LHC (HL-LHC). The ITk system consists of silicon-based pixel and strip sub-detectors. The strip detectors, fabricated by Hamamatsu Photonics, are based on an n⁺-in-p design with a 75 μm strip pitch and a 300 μm active thickness, and are expected to operate up to a fluence of 1.6x10¹⁵ 1-MeV neq/cm².
To better understand the fundamental behavior of the strip sensors and to guide their operation, we have developed a 2D Sentaurus TCAD model, tuned using optical and electrical characterization data from the test diodes fabricated on the same wafer as well as the main strip sensors. The simulation incorporates material defect models material defects measured from deep-level transient spectroscopy (DLTS), along with a dedicated interface model for the oxide layer in the peripheral region to improve agreement with laboratory measurements. By extending this model to the ITk main strip sensors, the simulations show good agreement with the extensive Quality Control data collected during sensor reception acceptance measurements. Finally, using this updated TCAD model as a starting point, we simulate device performance at the expected HL-LHC fluence and develop new irradiation models based on DLTS data and electrical measurements from irradiated test diodes.
