3D stacking induced mechanical stress effects

In this work the effects of 3D stacking technology on the performance of devices are systematically studied. For this study a special chip consisting of a number of stress sensors and vertical interconnect loops was designed and manufactured in 65 nm technology. Local variations of stress with a magnitude of up to 300 MPa are detected at different locations along the chip and are being characterized using finite element modeling and micro-Raman spectroscopy measurements.