A novel CVD polymeric anti-reflective coating (PARC) for DRAM, flash and logic device with 0.1 /spl mu/m CoSi/sub 2/ gate

A novel CVD polymeric anti-reflective coating (PARC) process has been developed for KrF lithography. The refractive index, n, and extinction coefficient, k, of PARC are tuned to match the optical properties of substrates. PARC is a conformal layer of thin polymer film, which significantly improves the CD uniformity of critical layers such as Poly Si gate and other features over topography. Since PARC is a pure polymeric material, it is easily removed by the conventional dry ash process. The ease of removal of PARC from Poly Si is particularly beneficial to the formation of salicide for advanced logic devices. In this paper, PARC is used to fabricate devices with 0.1 /spl mu/m CoSi/sub 2/ gate. Furthermore, the etching rate of PARC is about 500% higher than that of organic BARC for DUV photoresist, so that there is less DUV resist loss during ARC open step. PARC is a useful and low-cost process to extend KrF lithography for sub-0.15 /spl mu/m devices.