University of Manchester

Through-life electronics' reliability testing

David Mark Harvey
Project Completed

Scientific Case

The reliability of manufactured electronics is crucial to all. Failures in both industrial and consumer devices can be fatal and can cause problems in healthcare, transport, communications and daily living. To extend the lifetimes and reliability of products requires tests to be done when accelerating possible failure modes. One of the problems to solve is how to check when devices are starting to fail so remedial action can be taken before actual failure occurs. By monitoring the connections of devices at their solder joints it should enable through-life studies of joint degradation if imaging of cracks in joints is accurate enough to inform of impending failure.
Other
electronic manufacturing/test

Experiment Design

Two samples are planned to be imaged:
1. A printed circuit board od dimensions 10 cm by 10 cm by 1.6 mm. This board is populated on both sides with the interest on flip-chips with 109 solder joints under the chip. Chip size approx. 1 cm by 0.4 cm by 725 micron. Solder joints are approx. 140 micron diameter. Aim to gauge cracks across the solder joint from 1 micron to 140 micron diameter, with crack thickness unknown, but should be in micron range.
2. One flip-chip as in 1. but cut from the circuit board and potted as a cylinder of 31 mm diameter and 21 mm height. Aim to image cracks to 1 to 10 micron in solder joints as this chip should show failures across the joints.
Scanners and Rigs
Nikon Custom 320kV Bay
2
Not Required
1
Initial feasibility study, so a range of scans may be required.
Xradia VersaXCT
2
Not Required
1
Initial feasibility study, so a range of scans may be required.

Sample & Safety

Two samples are planned to be imaged:
1. A printed circuit board of dimensions 10 cm by 10 cm by 1.6 mm. This board is populated on both sides with the interest on flip-chips with 109 solder joints under the chips. Chip size approx. 1 cm by 0.4 cm by 725 micron. Solder joints are approx. 140 micron diameter. There are 8 chips of interest on one side on the board and 6 chips of interest on the other side.
2. One flip-chip as in 1. but cut from the circuit board and potted as a cylinder of 31 mm diameter and 21 mm height.
2
Low Hazard

Scan Records

Project Report