Dynamic Stress Analysis Applied to the Electrodeposition of Copper

Electrodepositioniscommonlyusedinelectronicpackaging,magnetic recording, copper interconnections in printed circuit boards and integratedcircuits,andMEMS(micro-electromechanicalsystems)devices. These films tend to develop sizable residual stresses as a result of the nucleation and growth process that can adversely affect reliability and service life. Various mechanisms have been proposed to account for the stress evolution that has been observed experimentally in both electrodeposited films and those grown from the gas phase. These stress-generating processes sometimes occur sequentially as the film morphology develops. More often, stress development is a balance between competing mechanisms. Multiple studies appear in the literature that address stress evolution during Volmer-Weber or 3D island growth of polycrystalline films. 1‐4 Generally, films show three stages of stress evolution during growth. Compressive stress is often observed in the pre-coalescence regime where the deposit is comprised of discrete nuclei on the surface. This compressive stress has been attributed to Laplace pressure