Here is the abstract you requested from the IMAPS_2008 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Electric NDT Method to Estimate Wire Bond Pull Force|
|Keywords: Electric method, NDT, wire bond|
|The microelectronics industry strives to create fast and reliable methods to estimate bond quality non-destructively. We report on using electrical contact resistance (CR) measurements to estimate the strength of ultrasonic wirebonds. A Kelvin-Cross Resistor measures the CR between the bond wire and the substrate. This value is used to estimate the contact area and thus the pull force of the contact. The method is a non-destructive, i.e. a measurement is done with no mechanical stress applied to the bond wire. A two-step experimental test was done to verify the applicability of the proposed method. A 4ó (64 ppm) false rejection level was measured when the disqualification limit of 2.5gf (16% of wire strength) were set according to the MIL-STD-833F-standard for the 25um Al wire. We propose the method for the US wirebond quality monitoring and pull force estimation.|
|Antti Kaskela, Student
University of Helsinki