Micro electronic systems via multifunctional additive manufacturing

Purpose

This paper aims to demonstrate the innovative functionality of additive manufacturing technology provided by combining multiple processes for the fabrication of packaged electronics.

Design/Methodology/Approach

This research is focused on the improvement in resolution of conductor deposition methods through experimentation with build parameters. Material dispensing with two different low temperature curing isotropic conductive adhesive materials were characterised for their application in printing each of three different conductor designs, traces, z-axis connections and fine pitch flip chip interconnects. Once optimised, demonstrator size can be minimised within the limitations of the chosen processes and materials.

Findings

The proposed method of printing z-axis through layer connections was successful with pillars 2mm in height and 550µm in width produced. Dispensing characterisation also resulted in tracks 134µm in width and 38µm in height allowing surface mount assembly of 0603 components and thin-shrink small outline packaged integrated circuits. Small 149µm flip chip interconnects deposited at a 457µm pitch have also been used for packaging silicon bare die.

Originality/Value

This paper presents an improved multifunctional additive manufacturing method to produce fully packaged multilayer electronic systems. It discusses the development of new 3D printed, through layer z-axis connections and the use of a single electrically conductive adhesive material to produce all conductors. This facilitates the surface mount assembly of components directly onto these conductors before Stereolithography is used to fully package multiple layers of circuitry in a photopolymer.