High Aspect Pattern Formation by Integration of Micro Inkjetting and Electroless Plating

TL;DR

This paper demonstrates a method combining micro inkjetting and electroless plating to create high aspect micro patterns on LTCC substrates, achieving precise, thick metal traces suitable for electronic applications.

Contribution

It introduces an integrated process of micro inkjetting and electroless plating for high aspect micro pattern fabrication on ceramic substrates, which was not previously reported.

Findings

Silver traces of 200 nm thickness were successfully printed.

Electroless nickel plating achieved up to 84 micrometers in thickness.

The process effectively forms high aspect micro patterns at desired locations.

Abstract

This paper reports on formation of high aspect micro patterns on low temperature co-fired ceramic (LTCC) substrates by integrating micro inkjetting with electroless plating. Micro inkjetting was realized by using an inkjetting printer that ejects ink droplets from a printhead. This printhead consists of a glass nozzle with a diameter of 50 micrometers and a piezoelectric transducer that is coated on the nozzle. The silver colloidal solution was inkjetted on a sintered CT800 ceramic substrate, followed by curing at 200 degrees C for 60 minutes. As a result, the silver trace with a thickness of 200 nm was obtained. The substrate, with the ejected silver thin film as the seed layer, was then immersed into a preinitiator solution to coat a layer of palladium for enhancing the deposition of nickel. Electroless nickel plating was successfully conducted at a rate of 0.39 micrometers /min, and the thickness of traces was plated up to 84 micrometers. This study demonstrates that the integration of inkjetting with plating is an effective method to form high aspect patterns at the demand location.