Development of mechanical fatigue test method for flip-chip solder joints

A controlled displacement mechanical fatigue test machine for specimens of flip-chip solder joints has been developed using PZT actuators. The extension response of the PZT exhibits good linearity using a charge control circuit. As a result of this control, errors in the strain of the specimen caused by the deflection of the test machine frame can be corrected by measuring the load. This test machine produces a cycle constant strain range in the solder joints. A fatigue test is conducted for specimens of flip-chip solder joints, and the fatigue strength of the joints is obtained. The strength of the joints seems to be higher than that of bulk solder