DFT / ATPG · All levels
DFT Interview Prep: Tricky Q&A
Senior interview and review questions for DFT Interview Prep.
Section Q&A bank
Use these drills after completing all topics in DFT Interview Prep. Answer with metric, mechanism, evidence, owner, and regression plan.
What separates a senior DFT interview answer from a junior one?
diagram
[INT][DFT][INTERVIEW-PREP]
Q: What separates a senior DFT interview answer from a junior one?
A:
A senior answer states mechanism, evidence needed, ownership, and regression decision criteria.
FOLLOW-UP TRAP: Tool command dump without reasoning.How do you answer 'coverage stuck at 97%' in an interview?
diagram
[INT][DFT][INTERVIEW-PREP]
Q: How do you answer 'coverage stuck at 97%' in an interview?
A:
Classify gap sources (untestable, constraints, model limits), prioritize highest-return fixes, and state quality-cost tradeoff.
FOLLOW-UP TRAP: Promising 100% without discussing constraints or cost.Q&A drill guide
diagram
METRIC -> MECHANISM -> EVIDENCE -> FIX -> REGRESSIONSketch while answering
diagram
INTERVIEW ANSWER LOOP
state metric -> explain mechanism -> request evidence -> propose fix -> list regressionKey takeaways
State metric, lot/corner context, and pattern tag with every claim.
Treat timing, power, and quality as one signoff problem.
Common pitfalls
Chasing coverage without legality checks.
Ignoring test-power side effects of pattern changes.
Debugging silicon without reproducible tags.