Silicon Wafer
Post-Lap Cleaning

One of the most important cleaning steps in the processing of silicon wafers is post-lap, or post-grind, cleaning.  If a wafer is not cleaned of all particles and organics prior to either caustic or acid etch, defects, staining and non-uniformity will occur. 

Although lapping debris should be removed in a post-lap rinse cycle, cleaning lines are designed to handle a significant amount of particulate matter and a variety of organic materials and metals.  Typically, two to three ultrasonic cleaning tanks are used in succession, with aggressive chemistry in the first tank, and milder chemistry often simply a DI water rinse in the last.  For increased effectiveness, operating temperatures for the ultrasonic tanks range from 50C to 70C, just below the cloud point of most detergents.  An amount as small as <.5% caustic can be added to the detergent tanks to increase cleaning efficacy.  Intersurface Dynamics ultrasonic detergents are utilized by major wafer manufacturers worldwide to ensure the cleanest possible post-lap results and hence the highest possible yield.

Vector HTC-Plus

Vector HTC-SCA Series