Advanced yield enhancement methodology for SoCs

A yield simulator utilizing the extracted critical area and a SoC yield management system has been developed. This system drastically improved accuracy of SoC yield prediction and successfully extracted the critical areas of all layers of 0.18 μm SoCs in approximately one hour. For yield prediction, we have thus far extracted critical areas of over 150 SoCs since the 0.18 μm nodes, and performed analysis of yield-loss factors. There are two factors that affect the device yield: field defects and product-inherent parametric failure. The yield calculated on the basis of critical areas is a prediction derived considering only field defects. It has been confirmed that SoCs failed to achieve the prediction had product-inherent parametric problems. The new system allows us to determine early in the development cycle whether or not a SoC has any inherent problems. The new system helps to quickly identify the root cause of a yield loss and reduce the time required to obtain yield improvement. Based on the experience of analyzing many SoC products, we have acquired design-for-manufacturing (DFM) expertise for improving yields for new and next-generation products.