"Another direction of improvement (of computing power) is to make physical machines three dimensional instead of all on a surface of a chip (2-D). That can be done in stages instead of all at once; you can have several layers and then many more layers as the time goes on." - an excerpt from talk delivered by Richard Feynman titled "Computing Machines in the Future" at the Gakushuin University in Tokyo on August 9,1985. Three decades later, advances in nanofabrication have enabled us to imagine, design, create and stack microchips for 3D Integration. Currently, heterogeneous 3D Integration is faster than Moore. This thesis details the development of processing technologies for the 3D packaging for integration of heterogeneous systems.