A p-type wafer has a diffused Phosphorous n-type junction with a junction depth of 0.15µm.
a) If the wafer (no pre-existing oxide) is to be oxidized at 1000 C for two hours to form a ‘dense, non-porous, high-quality' gate oxide. What is the gate oxide thickness achieved in this case?
b) At the subsequent step, the wafer is further oxidized at the same temperature to form another 0.1µm ‘low quality' oxide. What is the time needed to complete this ‘faster' process?
c) Does the original junction exist? Justify your answer in terms of assumptions you made.