Metrology and analysis

Which equation is used to determine film stress from the change in wafer bow before and after deposition?

  1. ABlack's equation
  2. BStoney's equation
  3. CPreston's equation
Show answer and explanation

Answer: B. Stoney's equation

Stoney's equation gives film stress from the substrate thickness and elastic constants, the film thickness, and the change in wafer curvature before and after deposition. Stress is evaluated by measuring wafer bow with a laser or similar means. Black's equation concerns electromigration, and Preston's equation concerns CMP removal rate.

Practice this topic Back to topic

More Metrology and analysis questions

  1. Whereas SIMS measures the atomic concentration of impurities, which method measures the depth distribution of electrically active carrier concentration?
  2. What is the measurement called that monitors a process by measuring product wafers partway through processing on the production line?
  3. Which inspection detects defects such as contact open failures using differences in brightness caused by differences in charging under an electron beam?
  4. When observing insulating samples with an SEM, which is a correct way to prevent charging (charge-up)?
  5. Which technology is being researched and introduced to measure shapes such as deep holes three-dimensionally without cutting cross-sections?