Comparison of Wafer-Level Spatial IDDQ Estimation Methods: NNR versus NCR Conference Paper uri icon


  • Extending the useful life of IDDQtest to deep submicron technologies has been a topic of interest in recent years. IDDQtest loses its effectiveness as the signal to noise ratio degrades due to rising background current and fault-free IDDQvariance. Defect detection using IDDQtest requires separation of deterministic sources of variation from defective current. Several methods that use deterministic variation in IDDQat the wafer level for estimating fault-free IDDQof a chip are proposed. This paper compares two such methods: Nearest Neighbor Residual (NNR) and Neighbor Current Ratio (NCR). These methods are evaluated using industrial test data for a recent technology. © 2004 IEEE.

author list (cited authors)

  • Sabade, S. S., & Walker, D.

citation count

  • 2

publication date

  • January 2004