Study of indium bumps for the ATLAS pixel detector

The bump-bonding technology is used to join the front-end read-out chips to the silicon substrate of the ATLAS pixel detector. We review the current status of the technology used by Alenia Marconi Systems and we report on the electrical and mechanical properties and the defect rate of the Indium bumps. # 2001 Elsevier Science B.V. All rights reserved.