ITC: Testing new nanomaterials
-- Test & Measurement World, 10/30/2006 10:26:00 AM
(Previous page: Validation and test synergy)
W. Robert Daasch, Professor of Electrical and Computer Engineering at Portland State University, on Thursday concluded the ITC series of invited addresses. He emphasized the importance of test in a presentation titled “It’s not what you can make, it’s what you can test.”His talk touched on the effects of process variations in emerging new nanomaterials, and he discussed how variations enter into testing, asking, “When is the endpoint of defect screening reached for yield or for reliability?” He also emphasized that it’s not too early to be asking such questions: “These new materials are not coming, they are here,” from companies including On Semiconductor and Nantero.
He cited some of the emerging difficulties: IDDQ signatures have evaporated, transition and path-delay screens require multi-loop search routines to control test time, and increasing defectivity will affect both circuitry and test access.
He advocated a test process that he illustrated with concentric circles, where data collection resides at the center, enclosed by a circle representing adaptive test. An outer circle represents a test framework that employs statistical post processing to convert test data to information.
He said tests will increasingly requires bracketed measurement ranges instead of single numbers, and reported on a specific example where he achieved test-time improvements through dynamic test reordering
He concluded by noting that new materials bring about increased defectivity, lower yields, and increased DPPM levels. He urged the audience to think about strategies to deal effectively with the emerging challenges. “We need to be in a position so we are not causing the bottleneck as these new materials come through.”
