SAN JOSE, Calif., May 4 -- VLSI Technology, Inc. and Numerical Technologies, Inc. have formed a joint development relationship to focus on the design and manufacture of sub-0.15 micron circuits. VLSI plans to use NumeriTech's optical proximity correction product to manufacture the circuits; it is also evaluating NumeriTech's phase shifting product for use in this process.The current generation of optical lithography equipment prints IC designs onto wafers at 248 nm, the wavelength of light. When IC features such as the gates on transistors are smaller than this wavelength, features become distorted or disappear completely. NumeriTech is addressing the problem by integrating phase shifting and optical proximity correction into each step of the manufacturing process, including design layout, mask manufacturing, process development, and silicon fabrication. VLSI expects to incorporate the NumeriTech technology into production use by the second half of 2000.