A combined socketed and non-socketed CDM test approach for eliminating real-world CDM failures

Of 30 bipolar, BiCMOS, and CMOS products socketed CDM classified, 27 had /spl ges/500 V withstand voltages and experienced no real-world CDM fallout. Two of three products with <500 V withstand voltages had numerous manufacturing-induced CDM failures until they were analyzed and redesigned. Analysis of these two products showed that both socketed and non-socketed CDM testing replicated the initial dielectric breakdown failure mechanisms at the same failure sites identified on real-world CDM failures. However, socketed CDM testing consistently induced more severe damage than non-socketed CDM testing. On one product, this resulted in a completely different failure mode than that on the socketed CDM and real-world failures. Based on this work, a combined socketed and non-socketed CDM test approach is proposed for classifying/evaluating new products and driving CDM robustness improvements.