Deposition (CVD and PVD)

What is the main purpose of "densification", a high-temperature anneal after depositing oxide by low-temperature CVD or similar?

  1. ATo make the film thicker
  2. BTo make the film conductive
  3. CTo compact the film and drive out moisture and the like, bringing its etch rate and electrical properties closer to thermal oxide
Show answer and explanation

Answer: C. To compact the film and drive out moisture and the like, bringing its etch rate and electrical properties closer to thermal oxide

Oxide deposited at low temperature has many voids and contains moisture and hydrogen, so it etches quickly and tends to insulate poorly. Annealing at high temperature compacts the film, drives out incorporated impurities and brings its quality closer to that of thermal oxide.

  • A. Annealing compacts the film, actually making it slightly thinner.
  • B. An insulating film does not become a conductor.
  • C. Correct. It densifies the film and improves its quality.
Practice this topic Back to topic

More Deposition (CVD and PVD) questions

  1. In ALD, what is the temperature range called in which self-limiting surface reactions keep the thickness per cycle constant?
  2. Which is an advantage of sputtering over vacuum evaporation?
  3. Which type of CVD reactor heats only the stage holding the wafer while keeping the reactor walls cool?
  4. Which is an example of the precursors used to deposit HfO2 gate dielectrics by ALD?
  5. Which model organizes, by temperature and gas pressure, the tendency of sputtered metal films to form columnar grains with many voids at low deposition temperatures?