DEVELOPMENT OF A DUAL BURN-IN POLICY FOR SEMICONDUCTOR PRODUCTS BASED ON THE NUMBER OF DEFECTIVE NEIGHBORHOOD CHIPS

Abstract

Most of the previous studies on developing an optimal burn-in policy for semiconductor products only deal with the burn-in process itself and little is concerned with utilizing the information on the quality levels of chips before being subjected to burn-in. Developed in this paper is a dual burn-in policy in which the number of chips (d) which do not pass the wafer probe (WP) test and lie in the neighborhood of a reference chip is utilized as an indicator on the quality level of that reference chip. The dual burn-in policy first classifies the chips which pass the WP test into two groups using a boundary value of d, and then each group is subject to burn-in for its own duration. For a certain type of 256M DRAM product, the performance of the proposed dual burn-in policy is compared to that of the single burn-in policy in which all chips are subjected to the burn-in of the same duration without considering d. The analysis results show that, for the cases considered, the proposed dual burn-in policy is more cost-effective than the single burn-in policy, implying that the additional information from the WP test is beneficial to establishing an efficient burn-in policy in semiconductor manufacturing.