Paper Title: Improved Process for Thin Glass Interposers

Paper Abstract: Thin glass substrates with through vias (TGVs) make excellent interposers for chiplet-based systems. Not only is glass much cheaper than silicon, but it also has high bulk resistance and low loss at high frequency and supports fine line/space patterning. However, thin glass substrates are difficult to handle in today’s fabs. A new approach uses a temporary bond created from silicon or glass handles. The bond tolerates high temperatures and creates stacks that can be processed like a silicon wafer. A simple mechanical debond yields the processed thin glass. Experimental data shows how to control the bond strength. Our current work involves metallizing bonded thin glass with TGVs. The temporary bond allows for void-free via fill and robust TGV structures. The temporary bond also supports double-sided metallization. The result is to greatly simplify the fabrication of devices using thin glass substrates, allowing device designers to take full advantage of their lower cost and many useful properties.

Paper Author: David Levy, Dir. R&D, Mosaic Mircosystems

Author Bio: David Levy is Director R&D at Mosaic Microsystems, a startup company where he supervises the development of wafer bonding, glass etching, and metallization technologies. He is a chemical engineer with over 25 years experience in chemical and semiconductor processes. He has made important technical contributions in fields including printed electronics, deposition methods (particularly atomic layer deposition), and laser processing, leading to over 90 patents. He has also published over 50 articles including recent ones in Chip Scale Review magazine and at the IMAPS International Symposium on Microelectronics. He earned a PhD in chemical engineering at MIT, where he studied the chemistry of hydrogen in materials for electronics and optics.