Project Title

Low-cost Additive Manufacturing Technique for Fabricating Through-Substrate Vias based three-dimensional micro-structures used in MEMS Applications

Project Images

Image Caption:Schematic showing cross-section of proposed MEMS inductor having vertical TSVs (a) with substrate (glass or silicon) (b) without substrate

Web Abstract

With increasing usage of Micro-electro-mechanical-systems (MEMS) devices in smart hand-held consumer electronics, fabrication of 3D microstructures and their subsequent packaging has become very important. This proposal aims to develop a low cost electrodeposition based additive manufacturing to create 3D microstructures, such as inductors required in MEMS applications. The fabricated 3D inductors by the proposed method will have reduced foot-print area and shorter electrical interconnect compared to conventional planer inductors. In these inductors, front-side structures will be connected to the back-side structures by metal-filled vias known as through-substrate vias. A low cost Electro-chemical-discharge-machining (ECDM) process capable of creating multiple vias in non-conductive semiconductor substrates will be demonstrated. Conductive metals such as copper, will be deposited in these vias by bottom-up electrodeposition. Dry-polymer lamination and spin-coated through-photoresist based electrodeposition will be used to create front and backside metallic structures. Characterization and reliability analysis of metal-filled TSV will also be performed.