Leak defect reduction of hard disk drives.

Abstract

Leak test is one of the function tests for Hard Disk Drives (HDD). It was realized that most of the leak defects are leak defects with leak defects at the Top cover and Base and leak defects from Screw Pivot Top cover float. The objective of this research is to reduce leak defect in Hard disk drives manufacturing by improving the air leak rate. To reduce the air leak rate, 5 phases of Six Sigma approach which are Define, Measure, Analyze, Improve and Control phases (DMAIC) are applied. At 95% confidence level, top cover screw fastening method and light brightness, with P-values less than 0.05, are significant factors for air leak rate. Then, the experiments are designed and performed based on Factorial experiment with two factors and three levels of each factor. At 5% significance level, there is no interaction effect between top cover screw fastening method and light brightness while the main effect is significant. The suggested process conditions for the minimum air leak rate are the fastening screw method by machine with lightbrightness at 600 Lux. Under this condition, the average of air leak rate is decreased from 0.364 mm.H2O to 0.190mm.H2O and the percentage of defect due to leak test failure is reduced by 73.81% from 0.42% to 0.11%.