High Aspect Ratio TGV Fabrication Using Photosensitive Glass Substrate

Compared with Si, glass has been regarded as a promising material for RF application because of its excellent electrical properties. The use of glass for RF applications has been proposed and developed for several years. However, because of the fabrication limitation, it's not easy to fabricate high aspect ratio through glass vias (TGVs). In this paper, TGVs with different shapes and sizes were fabricated with the photosensitive glass substrate which can be well structured, with a maximum aspect ratio of 11. The formation of TGVs on a 500-μm thick glass substrate was realized by wet etching in less than 15 minutes after thermal treatment.