The integration of 193nm Lithography is close to full production for the 90nm node technology and shows potential for lithographic resolution down to the 65nm node. The quality of 193nm reticles including binary, EAPSM and AAPSM must be outstanding so that low K1 factor reticles may be used in production.One area of concern in the IC industry is haze contamination on the mask once the reticle has been exposed to ArF radiation. In this study, haze was found outside of the pellicle and on the quartz side of the mask. Standard throughpell inspections might miss the contamination, yet its severity can ultimately affect mask transmission. For this reason, DuPont Photomasks and Cypress joined forces to quickly decipher how it develops.In this investigation, tests were devised which altered conditions such as mask environment, exposure, traditional and advanced cleaning chemistry. This paper describes the relationship between surface and environmental photochemical reactions, the resultant growth, analysis, and how it is controlled.

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Extreme Ultraviolet Lithography (EUVL) is the leading candidate for manufacturing integrated circuits beyond the 45-nm technology node. The masks for EUVL are reflective and significantly different from current transmission masks for deep UV lithography. Many authors have demonstrated the patterning of EUVL masks using different types of absorber stacks that were deposited on top of the multilayer reflector [1] . More recently, a new approach based on the etching of the multilayer reflector in order to define the mask pattern was proposed [2] . Using rigorous electro-magnetic simulations, it was shown that this subtractive approach could provide better process latitude, less H-V bias and smaller image-placement errors compared to the traditional masks based on the additive method. Even though the mask processing shows interesting challenges, this approach might offer immediate advantages over the more traditional patterning technique using the absorber stack, beyond those predicted for lithography imaging. These include the possibility to use optical inspection in transmission mode, which can provide the high-contrast images that are essential for high-sensitivity detection of small defects. In this paper, we present the first results on the patterning of EUVL masks using the direct etching the EUVL multilayer reflector (Mo/Si type) to produce EUV binary masks. In particular, we show how the process parameters can be adjusted to control the pattern side wall angle. We also present an analysis of the influence of this side wall angle on lithography imaging, based on lithography simulations. Finally, we show results from the optical inspection of these etched-multilayer binary masks (EMBM).