This is about MOSFET processing. 1. Does the thickness of the oxides grown in the lab correspond to the ideal thickness obtained from charts based on...

This is about MOSFET processing.

1. Does the thickness of the oxides grown in the lab correspond to the ideal thickness obtained from charts based on time and temperature? If it doesn't what reasons can you give to explain the discrepancy of the ellipsometer readings?

2. What effect do pinholes in the oxide have? Describe those effects for both the field oxide and the gate oxide.

3. In your own words, describe how to tell if the oxide has been removed from a silicon piece when wet etching the oxide.

4. Why is it so important to make sure that the photoresist on your substrate is completely developed before the next step of a process?

5. Why do we remove the phosphosilicate glass film from the substrate after the pre-deposition? What would happen if we didn't remove all the phosphosilicate glass? Why couldn’t we just pattern over that film and etch through in the areas we want opened I the next step?

6. Why do we do an oxide etch during our cleaning process if we have an oxide on the substrate that we want to keep?