Method and apparatus for accurate alignment of integrated circuit in flip-chip configuration

Abstract

In a method for mounting an integrated circuit onto a substrate in a flip-chip configuration, a circuit alignment feature on the processed surface of the integrated circuit and a substrate alignment feature on the mounting surface of the substrate are used to accurately align a set of bonding pads on the processed surface of the integrated circuit with a corresponding set of contact pads on the mounting surface of the substrate. The positions of the circuit and substrate alignment features are determined, and a separation between these alignment features which will result in accurate alignment of the bonding pads to the corresponding contact pads is calculated. The circuit is moved with respect to the substrate in order to achieve this predetermined separation. The method may be carried out using an apparatus which includes a die placement fixture and a substrate placement fixture. An alignment feature detection system is used to determine positions of circuit and substrate alignment features, and an alignment controller coupled to the alignment feature detection system is adapted to move the circuit fixture with respect to the substrate fixture such that predetermined separation between the circuit and substrate alignment features is achieved.