Megasonic Enhanced Electrodeposition

TL;DR

This paper introduces a megasonic acoustic streaming technique that enhances electrodeposition in high aspect ratio microvias, enabling more efficient and controlled manufacturing of interconnections and MEMS devices.

Contribution

It presents a novel megasonic-assisted electrodeposition method that significantly improves filling of deep microvias with high aspect ratios.

Findings

Reduced Nernst-diffusion layer to sub-micron scale

Achieved conformal electrodeposition in deep grooves

Increased throughput and control in manufacturing processes

Abstract

A novel way of filling high aspect ratio vertical interconnection (microvias) with an aspect ratio of >2:1 is presented. High frequency acoustic streaming at megasonic frequencies enables the decrease of the Nernst-diffusion layer down to the sub-micron range, allowing thereby conformal electrodeposition in deep grooves. Higher throughput and better control over the deposition properties are possible for the manufacturing of interconnections and metal-based MEMS.