High volume microprocessor test escapes, an analysis of defects our tests are missing

This paper explores defects found in a high volume microprocessor when shipping at a low defect level. A brief description of the manufacturing flow along with definition of DPM is covered. Three defective devices are then root cause analyzed for defect type, electrical effect and possible ways to screen earlier in the device life cycle or manufacturing process. The implications of these defects along with process trends are used to forecast the need for better tools and methods to earlier achieve high quality goals. OVERVIEW Much attention has been paid to the effectiveness of test coverage versus Defects Per Million (DPM) at the start of production of a device. Several published papers clearly demonstrate the correlation between fault coverage and DPM [4,9]. Little, if any, attention has been paid to what is needed to achieve the required low DPM levels in high volume manufacturing. The normalized chart in Figure 1 shows the typical volume growth and DPM reduction curves for a compl...

• Type: Conference
• Year: 1998
• Where: ITC
• Authors: Wayne M. Needham, Cheryl Prunty, Yeoh Eng Hong
• Keywords: DPM Reduction Curves, Hardware, ITC 1998, Low Dpm, Required Low Dpm