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Material for Contrast Enhanced Lithography ( MCEL ) containing diazonium salt as a photobleachable material was developed for submicron optical lithography. New MCEL offers the following advantages. 1. Good thermal stability in solution and in film. 2. High A value ( A value : max 12 μm-1 ). 3. Good solubility to alkaline solution. 4. Excellent wettability. 5. No intermixing layer between MCEL and photoresist. In this study, we investigated the effect of MCEL on the characteristics of photoresist, such as sensitivity, gamma value, resolution, development time, exposure latitude and focus latitude, using a g-line wafer stepper with 0.35 NA lens and commercially available photoresist A as bottom layer. Key results are: 1. Incident dose was about 3 times larger than that of photoresist A. 2. Gamma value, resolution was remarkably improved and 0.7 μm line and space pattern with vertical wall was obtained and also the resolution of 0.6 μm line and space pattern was possible. 3. The focus tolerance was wider, however, the exposure tolerance was not improved. It is confirmed that newly developed MCEL had excellent properties for achieving the submicron fine patterns and wide process tolerance which assured high yields of the integrated circuits production.