Studies for an upgrade of ALICE Inner Tracking System: Pixel chip characterization

Inner Tracking System (ITS) of ALICE is used for vertex determination and tracking. Future heavy-ion program at the LHC aims to run with high luminosity. To address this challenge, upgrade program of ITS is underway, which aims at better position resolution (factor of 3), high detection efficiency (>99%), high-rate readout capabilities (100 kHz for Pb-Pb) and moderate radiation hardness (> 700 krad). The new ITS will be composed with 7 layers of silicon pixel chip based on Monolithic Active Pixel Sensor (MAPS) technology. The characterization test of various version of prototype chips at different phases of development has been performed. This contribution will provide the main characterization results obtained from the measurements performed at laboratories and using test beam for finalizing the pixel chip specification.