Question

what co­mbination of basic masks combine together to make a N-MOS tr­ansistor?  Which ones are used for a P-M­OS transistor?

Answer 1

To create pattern layers on the silion wafer we use different types of masks. this maks are used in different stages.

masks are made of glass paltes and green plates. but this two types of masks are less expansive and easly damaged so instead of these two types of masks we replace with iron oxide or chromium , both of this more durable and give longer life when compared with green plates and glass plates.

there is no seperate masks for N-MOS and P-MOS depend upon our investement we can choose either of the masks.