The trimethylsilane (3MS) based low-k a-SiC0:H films can be made using 3MS, He and N 2 0 in typical PECVD equipment. In this study, the structure, composition, and electrical characteristics of these films were evaluated with different process conditions. Rl3S and FTIR were evaluated to understand the composition and structure of films. The films have been characterized as-deposited and after annealing at 4OOOC to see the thermal stability. 3MS low-k a-SiC0:H films showed low bulk film density ( 1.14 -1.34 g/cm3), low-k (2.6 < k < 3.2), low leakage current density (J < lo-'' A/ cm2 at lMV/cm), and relatively high breakdown field (E > 4 MV/cm at lmA/cm2).

Wafer thinning represents a critical step in 2.5D and 3D-IC integration. Achieving low total thickness variation (TTV) of a bonded stack is essential since it directly impacts the TTV of the thinned device wafer. It is essential to understand and utilize appropriate processes and materials that provide precision bonded stacks prior to thinning operations in order to achieve high process yields. The 3M™ Wafer Support System and Corning's precision glass carrier wafers were used to produce bonded stacks. Leveraging metrology tools like the Flatmaster MSP-300 and low coherence interferometric probes allow for characterization of the TTV of each layer of a bonded stack and better understanding of the stack-up as well as how to minimize stack TTV. The ability to deliver stack TTV of &lt; 2 um in a repeatable manner has been demonstrated.