LOL, Lin. I think you are asking the wrong question. Water is one of the most polar molecules in nature. You should consider modifying the suface of your substrate to make it more polar. This is typically done by vapor deposition of a polar molecule onto the substrate. Bill Moffet, can you comment on the particulars? -Mike Martin U. of Louisville >>> "lin yu"08/21/06 11:52 PM >>> I'm doing some self alignment study by using the capillary force of water. But the problem is water can't provide enough force to align my samples. So I'm thinking if water is more polar, the capillary force can be bigger, which is good for my case. Does anyone have any idea how to make water more polar by adding some kind of liquid in it? Please give me some suggestion. Thanks a lot!