Study on the Characteristics of a Silicon Pixel Chip for the ALICE-ITS Upgrade Project

The ALICE (A Large Ion Collider Experiment) is a general purpose experiment dedicated to the study of heavy-ion collisions at the Large Hadron Collider (LHC). The main goal of the ALICE-ITS (Inner Tracking System) upgrade project is to improve the vertexing and the tracking capabilities at low $p_T$ according to projected increase in the luminosity at the LHC. The new ITS is, therefore, based on the latest silicon pixel technology and is designed to increase the data-taking rate with a new readout system and to reduce the pixel size and the material budget. We constructed a pixel chip test system at Pusan National University (PNU) to measure the characteristics of the pixel chips. We measured the characteristics of the prototype pixel chips for the new ITS by using PNU's system and analyzed the results for the characteristics of the pixel chips. We have been studying the optimized pixel chip geometry for the new ITS through the measurement results. This paper focuses on the ITS chip characterization test system built at Pusan National University and the measurement results.