This Small Business Innovation Research (SBIR) Phase I project will develop reversible contrast enhancement layers (R-CELs) for 248 nm lithography and 257 nm mask writing. Optical lithography is a key process in semiconductor manufacturing and mask writing. The R-CEL will help to break the diffraction limit facing the optical lithography. The application of R-CELs will enable lithographers to obtain higher resolution from their lithography and mask writing tools, extending the lifetime of the current infrastructure. R-CELs can also reduce lithography operating costs by increasing the process window and reducing the need for resolution enhancement technologies. The R-CELs proposed here will increase the productivity of wafer writing at 248 nm and mask writing at 257 nm. For wafer manufacturing, the R-CEL will extend 248 nm lithography to the 45 nm node, to circumventing the more expensive 193 nm lithography for certain processes. <br/><br/>Commercially, this could save hundreds of millions of dollars for the industry by increasing the lifespan of the existing infrastructure and reducing the cost of lithography operations. The other application of the R-CEL concept, in 257 nm mask writing, will improve the competitiveness of optical mask writing tools compared to the slow and unreliable e-beam mask writing tools, thus reducing the cost of mask sets, especially cutting-edge masks, which are the leading cost of small to mid volume ASIC production. <br/>It is predicted that the total available market for the R-CEL for 248 and 257 nm will reach $200M in 2007.