After etching and rinsing, an IPA (isopropyl alcohol) vapor dryer can produce dry silicon wafers without watermarks and limited particle adders. IPA drying is also known as Marangoni drying, relies on the Marangoni effect of low surface tension of IPA compared to water.
When IPA vapor is introduced into the drying chamber in an IPA vapor dryer, a surface tension gradient is established between the IPA and water on the surfaces of the silicon wafers. The surface tension gradient causes water to flow off the silicon wafers and they are left clean and dry. In addition, the slow drain of water feature also helps to minimize particles that contaminate the wafer surfaces. It results to clean wafers after a final etch and before the next semiconductor manufacturing step.
IPA vapor dryers are particularly suitable for drying thin, delicate silicon wafers. It dries the wafers without moving them, unlike in other drying methods, and they are not subjected to any stress. As a result, any damage is minimized while the drying performance remains excellent.
The IPA vapor dryer improves wafer processing after the final hydrofluoric acid etching. The wafer has to be rinsed with de-ionized water and dried before undergoing the next manufacturing step. Providing a clean wafer with a low particle count is crucial at this stage because the following process steps will be affected by the presence of leftover contamination or particles. Because IPA vapor dryers remove water from the water surface and reduce particle counts with the Marangoni effect, the IPA vapor dryers improve wet processing equipment results and ensure higher quality output.
The complete article, “How the IPA Vapor Dryer Provides Superior Wafer Processing,” goes into further detail. If you have questions, or you would like to set up a free consultation, contact Modutek at 866-803-1533 or email Modutek@modutek.com.