Detection and sizing of particulate contamination in rigid disk drives: instruments and sampling techniques

Aerosol sampling instruments, their operating principles, availability, applicability with respect to head-disk interface (HDI) research and manufacturing, and price are presented. Experiments were conducted using a laser particle counter to address sampling issues of background elimination, sampling frequency and sampling location for HDI tests. Results show that continuous sampling was acceptable and sampling at either leading or trailing edge of the interface did not affect sampling performance appreciably.