Novel Si Etching and Dielectric Liner Film Processing Technologies for Low-Cost TSV Packaging
A new etch process has been developed for scallop-free and taper-shaped TSV fabrication . By using a direct etch process instead of cycled etching, TSVs were obtained with smooth-sidewalls and tapered profiles. The absence of scallops has a positive effect on signal transmission speed. Also, the direct etch process allows for shorter TSV fill process times and thus provides lower cost of deposition processes like PE-CVD, PVD and Cu-ECP (electrochemical plating) [2,3]. A cost correlation of taper-shape etching and Cu-ECP (electro-chemical plating) will be included.
For the TSV isolation, polyurea dielectric liners were successfully deposited using a vapor deposition polymerization technology (which is Ulvac’s FPF/PV large panel technology). This process allows for isolation liners in next-generation high-frequency devices and for the film formation into a TSV pattern.
In summary, a novel low-cost TSV fabrication flow can be provided for 2.5 / 3D Si integration in high-frequency applications. The process flow yields scallop-free and taper TSVs, which can be filled effectively with electroplated copper and polyurea dielectric liners.
 Y. Morikawa, et al., “Scallop Free TSV Etching Method for 3-D LSI Integration”, Proc. Int. Symp. on AVS 57th, Albuquerque, New Mexico, Nov. 1, 2010, p 121.
 Y. Morikawa, et al., “A Novel Scallop Free TSV Etching Method in Magnetic Neutral Loop Discharge Plasma”, in Proc. IEEE Electronic Components and Technol. Conf. (ECTC 2012), San Diego, CA, May 29 – June 1, 2012, pp. 794–795.
 Y. Morikawa, T. Murayama, Y. Nakamuta, T. Sakuishi, A. Suzuki, and K. Suu, “Total Cost Effective Scallop Free Si Etching for 2.5D & 3D TSV Fabrication Technologies in 300mm Wafer”, Proc. IEEE Electronic Components and Technol. Conf. (ECTC 2013), Las Vegas, NV, USA, May 28 – 31, 2013, pp. 605–607.