Novel copper metallization schemes on ultra-thin, bare glass interposers with through-vias

Metallizing ultra-thin glass interposer with through-vias with high adhesion and at low cost is one of the primary challenges in producing next-generation glass-based system packages. This paper describes and investigates a new approach towards creating a glass interposer structure with through-vias that is ready for solution-based metallization such as electroless deposition. Starting with glass containing through-vias, a thin polymer film (primer) is laminated, covering the entire surface. The film is then opened over the vias, resulting in a structure that is ready for electroless deposition and is known to be thermo-mechanically reliable. The versatility and feasibility of this approach are demonstrated through the use of various primer film materials and primer opening processes. Daisy-chain reliability structures were fabricated on glass interposers metallized by this approach and electrical measurements showed expected behavior.