It becomes increasingly important to have an integrated process for Extreme UltraViolet (EUV) mask fabrication in order to meet all the requirements for the 32 nm technology node and beyond. Intel Corporation established the EUV mask pilot line by introducing EUV-specific tool sets while capitalizing on the existing photomask technology and utilizing the standard photomask equipment and processes in 2004. Since then, significant progress has been made in
many areas including absorber film deposition, mask patterning optimization, mask blank and patterned mask defect inspection, pattern defect repair, and EUV mask reflectivity metrology. In this paper we will present the EUV mask process with the integrated solution and the results of the mask patterning process, Ta-based in-house absorber film deposition, absorber dry etch optimization, EUV mask pattern defect inspection, absorber defect repair, and mask reflectivity performance. The EUV resist wafer print using the test masks that are fabricated in the EUV mask pilot line will be discussed as well.
Polarized ultraviolet light from an excimer laser (193 nm) was used to photodesorb and photodissociate N2O and NH3 adsorbed on a cold Pt(111) surface. The photodesorbed species and their time-of-flight (TOF) were monitored by Resonantly Enhanced Multiphoton Ionization spectroscopy. For N2O, we have observed both the ejection of ballistic O atoms and the release of slow thermalized N2 molecules. The ballistic oxygen atoms leave the surface either in the ground state O(3P) or in the first electronically excited state O(1D). A lobular angular distribution pointing away from the surface normal was measured for the ballistic O(3P) in agreement with a binding geometry where the linear N2O is tilted N-end down on the Pt(111) surface. Evidence for the production of N2 photofragments thermalized by the surface includes both low (approximately 90 K) rotational and translational temperatures of the N2 as well as a lack of correlation between rotational and translational energy. For NH3 the irradiation of a submonolayer coverage largely favors the desorption rather than the dissociation of NH3. For multilayer coverages however, a strong dissociation channel is activated and atomic H is seen to desorb from the surface. A bimodal distribution was found for the TOF of the H photofragments. The fastest channel (0.7 eV) corresponds to the ejection of undeflected ballistic H fragments produced near the surface. For bulk NH3 photodissociated deep within the multilayer, the TOF of the H radicals shows an unexpected thermalized distribution.