Abstract
The electrodeposition of pure gold is an enabling technology for wafer bump and wire bonding interconnect applications. Most conventional pure gold electroplating processes used in the electronics industry are cyanide based. Due to the toxicity of the free cyanide formed during electrolysis, as well as cyanide's incompatibility with positive photoresists, sulfite-based gold processes have been the traditional alternative for wafer applications. However, traditional sulfite-based processes have suffered from issues with solution stability and the necessity for annealing to achieve the desired deposit hardness. This paper describes a stable non-cyanide process that can be used for soft gold electroplating. Electrochemical characterization of two non-cyanide processes will be presented to illustrate the electrochemical behavior of gold in the presence of different complexing agents. The effects of operating parameters on process performance, including cathode efficiency, deposit purity, hardness, solderability and solution stability will be presented. The thickness uniformity, surface morphology and topography of the electrodeposited gold bumps, as well as wire bonding performance, will also be presented.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 242-246 |
| Number of pages | 5 |
| Journal | Proceedings of the IEEE/CPMT International Electronics Manufacturing Technology (IEMT) Symposium |
| Volume | 29 |
| State | Published - 2004 |
| Event | IEEE/CPMT/SEMI 29th International Electronics Manufacturing Technology Symposium - San Jose, CA, United States Duration: Jul 14 2004 → Jul 16 2004 |
All Science Journal Classification (ASJC) codes
- Industrial and Manufacturing Engineering
- Electrical and Electronic Engineering