Virginia Semiconductor Inc. has been producing ULTRATHIN® Silicon substrates since 1988 (<250um thick). After many years of development, VSI offers Double Side Polished silicon wafers as thin as 8-12um and Single Side Polished wafers as thin as 90um. These extremely thin wafers and foils have been produced for niche-market customers and R&D specialists. ULTRATHIN® Silicon Wafers having diameters ranging from 25.4mm to 150mm have been supplied. VSI has also supplied thermally oxidized ULTRATHIN® Silicon Wafers with a range of oxide thickness; even the thinnest VSI silicon wafers and foils have been successfully oxidized. In 1994 VSI was awarded the Photonics Circle of Excellence Award for ULTRATHIN® Silicon Wafers used in optical applications. Only 25 products each year are selected for this award. After ten additional years of development and production, our ULTRATHIN® Silicon wafers have found use in a variety of R&D and manufacturing applications. Today the VSI thin wafer
products enjoy greatly improved surface micro-roughness and total thickness variations. However,
these specifications can not presently match those of standard Double Side Polished or Haze-Free
Wafers. Several manufacturers are using small quantities of these wafers in full sensor fabrication processes and commercial products (both 100mm diameter and 150mm diameter). When handling ULTRATHIN® Silicon Wafers VSI recommends using shovel style Teflon coated tweezers or modified vacuum wands or vacuum tweezers. Although these wafers are extremely flexible, they will quickly break under the wrong forces or pinching. Also, one must be very careful handling
these wafers. HEPA filters and air handling systems make handling these wafers difficult, since the wafers are foils and can easily float away.
VSI owns all rights to use the name ULTRATHIN® as related to silicon wafers and processed silicon wafers (US Trademark Registration has been awarded)