Bump bonding of pixel systems

A pixel detector consists of an array of radiation sensing elements which i s connected to an electronic read-out unit. Many different ways of making t his connection between these two different devices are currently being used or considered to be used in the next future. Bonding techniques such as fl ip chip technology can present real advantages because they allow very fine pitch and a high number of I/Os. This paper presents a review of the diffe rent flip chip technologies available and their suitability for manufacturi ng pixel detectors. The particular problems concerning testing of pixel det ectors and thermal issues related to them are pointed out. (C) 2001 Elsevie r Science B.V. All rights reserved.