Stress in electroplated gold on silicon substrates and its dependence on cathode agitation

Suan Hui Pu, Andrew S. Holmes, Eric M. Yeatman
2013 Microelectronic Engineering  
The influence of cathode agitation on the residual stress of electroplated gold has been investigated. Using a custom-built plating cell, a periodic, reciprocating motion was applied to silicon substrates that were electroplated with soft gold. A commercially available gold sulfite solution was used to deposit the 0.6 lm thick gold films using a current density of 3.0 mA/cm 2 and a bath temperature of 50°C. By increasing the speed of cathode agitation from 0 to 5 cm/s, the magnitude of the
more » ... essive stress decreased from À64 to À9 MPa. The results suggest that cathode agitation significantly alters the mass transport within the electrolytic cell and can be used as a method of stress control in gold electroplating. This finding is potentially significant for plating applications in microelectronics and microsystems that require precise stress control.
doi:10.1016/j.mee.2013.05.019 fatcat:vgcnqc5xibfghcpmjac6gb4d4m