| . The backside of the wafer is always towards the "H" bar in the cassette. |
. Some general facts about Bow on an SOI wafer. The bow is caused
by the stress of having an oxide on only one side of the handle. The
thicker the oxide the higher the stress, the thinner the handle the
easier it is to Bow. |
| Possible Solutions: |
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1) Have a thicker handle
2) Use a thinner burried oxide
3) Leave the oxide on the back of the handle wafer.
4) Grow the oxide on the device wafer
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. Device fringes - on fusion bonded SOI wafers with device
thicknesses less than 8um the oxide fringes are normally visible.
The fringes are caused by angstrom thickness variations in the
oxide. This is also another way to tell the device side or font side of
a fusion bonded SOI Wafer. |
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