EBL / Electron Beam Lithography

Electron beam lithography (EBL) is a versatile mask-less (“direct-write”) patterning technique based on the exposure of an electron-sensitive material (termed as resist) to a focused electron beam. Following resist deposition on the sample and baking, the electron-beam is scanned over the sample in accordance to the pattern as designed by the user using appropriate CAD tools. Subsequently, the exposed or unexposed areas of the resist are selectively dissolved in a suitable solvent. This results in the engraving of the user-defined pattern or its reverse into the resist. Depending on the EBL system and the exposed materials, sub-20nm feature resolution and accuracy in pattern positioning can be achieved. Unlike optical lithography which requires photomasks for pattern projection, EBL gives the user the flexibility to create and test various structures and patterns at the micro/nanoscale before choosing the more suitable solution for his needs.

Access to the following two EBL tools is provided: (1) Raith EBPG5000plusES and (2) FE-SEM Jeol 7000F with Raith Elphy Quantum. Dense sub-20nm patterns and sub-10nm isolated features are feasible for a sample size up to 4 inch in diameter. Attainable multi-level lithography alignment accuracy is less than 20nm.