1. Obviously you have more consumables per wafer. This includes items like Raw Wafer Cost, Photoresist, gases etc. Thus consumables will be 2.25x, but this impact should be small, since consumables are not significant.
---No argument there.....
2. Any 300m tool will cost more than 200mm tool. WAG - 30% extra. Thus depreciation will be 30% extra.
---Maybe. Did you know that many of the current 0.13u Process Tools are ALREADY 300mm capable??? And some tools should only need slight modifications to Wafer Stages, and wafer transport systems. Of course I really haven't noticed that same capability in the 0.25u Tools I've seen. Depends on what you have when you make the transition.
3. Labor and overhead cost will be the same per wafer.
---Maybe even cost less. A trend that I've noticed in each subsequent tool generation, has not only been improved tool performance, but also in the tool's automation itself. For example, when I came up through the ranks, a Scanning Electron Microscope required one operator per scope, now, 1 person can run 3 SEM's.
So I expect the percent yield on the 200m core of the 300mm wafer to be equivalent to the 200mm wafer, but a significantly lower yield for the remainder( outer core) of the wafer. All pieces of equipment do not suffer from this problem. However a silicon wafer has hundreds of process steps, and it takes just one process step which is poorly understood by the vendor or the process engineer, for the yield to be less than expected.
---Whoooooo now baby, Ya start dissen Process Engineers THEN THEM'S FIGHTEN WORDS!!!! O.K., the Litho People are Space Cadets, but that's to be expected.
:-)
---Actually yield isn't the issue with edge die. Nobody wants to spend millions on a piece of equipment, to have poor Cross Wafer Sigma. It just doesn't happen anymore. More likely, the variations you would see on edge die are most likely bin split related. Maybe that's what you meant by yield??
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