CMS pixel upgrade for the phase I: Module production and qualification

The present CMS pixel detector has been designed to be fully efficient up to an LHC luminosity of 10(34) cm(-2) s(-1). However, the luminosity will increase by a factor of two in the coming years. Therefore it is planned to build and install a new detector in the extended year-end technical stop in 2016-17. Barrel pixel modules are in production since spring/summer 2015 in five different centers. Module production requires bump bonding, wire bonding and gluing processes to finally assemble a full module. To have a uniform performance of all modules standard qualification procedures have been developed. All modules will be subjected to 10 thermal cycles between +17 degrees C and -25 degrees C and then electrically tested. In addition, module performance will be verified under high rate X-rays, and internal calibrate signals used for electrical tests will be calibrated in units of electrons using well defined X-ray fluorescence lines from different target materials. The qualification criteria, based on which modules are selected to be used in the final system, will be explained in detail. (C) 2016 Elsevier B.V. All rights reserved.