Case Studies

These case studies were exerpted from a paper, Future Trends in Test, presented by Inovys at ITC 2004.

Case Study 1 | Case Study 2 | Case Study 3 | Case Study 4
 
AC Characterization - Case Study #1
 
  • Customer
  • IP Core provider that must evaluate test chips for hard core certification.
  • Main use
  • Characterization of first silicon test chips.
  • Goals
  • Understanding timing and performance
  • Technique
  • AC Scan using Path Delay and launch-to capture VCO-driven on-chip clocking.
  • Alternative method
  • Functional vectors applied at-speed.
  • Advantage
  • Deterministic targeted evaluation of AC coverage in a desktop environment.
  • Added Commentary
  • The desktop or lab-bench environment is ideal compared to physically taking parts over to a rent-a-tester test floor. The unit is easy to learn, and once the scripts and methods are in place, a whole tray of parts can be tested in about a half-hour.
  • Innovys Solutions
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Functional vs Structural - Case Study #2
 
  • Customer
  • Chip provider that must evaluate test chips and first silicon.
  • Main use
  • Comparison of functional methodology versus structural
      methodology.
  • Goals
  • Understanding coverage, tradeoffs, techniques and schedules.
  • Technique
  • Application of both functional and structural vectors on identical parts
      and on both structural and functional testers.
  • Alternative method
  • Application of scan on traditional functional testers on a test floor.
  • Advantage
  • Experiments conducted in desktop environment to compare and
      contrast both functional vectors applied on functional testers and
      structural vectors on structural testers.
  • Added Commentary
  • While the desktop structural tester is designed primarily for structural
      testing, it is also a very capable machine for initial silicon validation
      using functional test patterns as long as those patterns meet the
      reduced edge-set handling requirement. This technique provides a
      cost effective method for silicon bring-up, working in conjunction and
      in parallel with silicon debug on big iron ATE.
  • Innovys Solutions
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Production Probe - Case Study #3
 
  • Customer
  • Chip (IDM) provider that must sustain full production probe.
  • Main use
  • Production wafer probe for devices with strong DFT.
  • Goals
  • Sustained throughput at the lowest cost.
  • Technique
  • Using a low-cost, DFT tester.
  • Alternative method
  • A functional big-iron tester.
  • Advantage
  • Lower asset cost of equipment, lower operational cost, small
      footprint, and meets or exceeds all requirements for the probe
      insertion. Also, it fits within the capabilities and limitations of testing
      through probe needles.
  • Added Commentary
  • As an added benefit, the chosen platform accelerated test
      development and deployment.
  • Innovys Solutions
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Test Program Development - Case Study #4
 
  • Customer
  • Chip (IDM) providers that must develop the test program for
      production test.
  • Main use
  • Rapid development and validation of production test program.
  • Goals
  • Reduced time-to-test program.
  • Technique
  • Using the desktop and production-sized tester as a vector
      development vehicle in conjunction with EDA tool links to prove out
      ATPG vectors; restricted functional vectors (meeting edge set
      restrictions); and to provide fail information that allows diagnosis to
      be conducted (to fix vectors).
  • Alternative method
  • Test program development on a big-iron functional tester.
  • Advantage
  • Reducing the time to validate vectors and turn them into test program
      components.
  • Innovys Solutions
  • Ocelot ZFP - Best Test Coverage for New, High Performance SoC Devices
  • Ocelot - The Most Cost-Effective Manufacturing Test System for Complex SOC Chips
  • FlopPlot Analysis Software - Visually Identify and Diagnose IC Faults Faster
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