Cross section of The Surface Tension Gradient Dryer

The Gradient Dryer uses the difference between the surface tension of H2O and IPA to produce a gradient that generates fast and effective substrate drying. Surface tension gradient drying yields substrates that are watermark-free with low particle counts and no feature damage. Since there are no metallic components inside the dryer chamber, charge damage is virtually eliminated. There are no moving parts in the Gradient Dryer, and the elimination of spin drying dramatically reduces breakage, especially critical for today’s thinner substrates.

Besides the elimination of watermarks on hydrophilic, hydrophobic and combination films, surface tension drying provides other benefits. This drying method does not place any mechanical stresses on the substrate. The technique works well on practically any flat substrate. No surfactants are necessary to change the substrate properties to enhance drying performance. Compared to traditional vapor dryers, Gradient Dryer dryers consume very little IPA. When integrated with cleaning and rinsing, this tool can provide a one-step process for such applications as the fabrication and cleaning of ICs, solar cells, fuel cells, MEMS and disk drives.

The Gradient Dryer processes a batch of 25 or 50 wafers in ~10-15 minutes depending on configuration. The dryers are configurable to accept one or two cassettes from 150mm to 300mm and can be produced as stand-alone units or integrated into wet processing stations.