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kimmylsm
Sep1-09, 05:35 AM
In deposition of thin film on a p-type silicon, how to make sure the thickness of the thin film will not affect or affect the least the electrical(Hall Effect) and structural properties? how to know how thick is the thin film that most suitable? can it be calculated? by the way, the thin film deposited is zinc oxide using sol-gel and spin coating(where thickness depend on speed are set)?

pseudophonist
Nov22-09, 07:05 AM
You'd want to try to lattice match as close as possible and make sure the fermi levels line up approximately well. Structurally, the thinner the film the better. Electrically, i'm not sure since if it doesn't affect the silicon it won't be behaving like zinc oxide.

Mapes
Nov22-09, 09:30 AM
You'd want to try to lattice match as close as possible

Lattice matching isn't possible here, even approximately. Lattice matching may occur when a crystalline film or structure is grown slowly on a substrate with (approximately) the same lattice constant. It will never occur with spin coating.

You do want to avoid large compressive or tensile stresses that can be created by further processing steps (perhaps this is what pseudophonist meant). Large film stresses can cause wafer bow, delamination, cracking, buckling, and so on.