Particles Detection and Analysis of Hard Disk Substrate after Post-CMP Cleaning

Abstract

Scrub, ultrasonic and megasonic are widely used in industry as post-CMP cleaning procedure. In this paper, experiments are taken to analyze the particle contaminations after each process. A scatter spot method has been exploited to exam the particles’ location and features. SEM with EDX is used to observe and analyze the particles’ shape and size as well as the elements. The results indicate that brush scrub is not sufficient for submicron abrasive particle removal. Megasonic is a better method of cleaning but contaminations like metallic particles and bacteria fiom the equipment may pollute the clean disk. The abrasive particles embedded in the plating pits are hard to remove by mechanical force. Pollution in the dryer is also discussed.