HIGH-RESOLUTION X-RAY-LITHOGRAPHY - ITS ULTIMATE LIMITS

Proximity X-Ray Lithography (XRL) using synchrotron radiation has proven its ability to replicate patterns in the sub-100nm regime, corresponding to the 1 Gigabit integration density for circuits and memories (DRAMs). In that context, the L2M research activities are focused on the ultimate limits in resolution. This paper describes the nanomask technology. It discusses about resolution and replication process latitude in the resist by comparing theorical simulations (L2M code) and very short proximity exposures. 50nm-width patterns have been successfully obtained at very small gaps (less than or equal to 10 mu m). Finally it will be shown that the ultimate resolution should be lower than 20nm.