40k V electron beam lithography has been used to pattern gold plated x-ray masks containing GBit DRAM complexity layouts. The two commercial e-beam resists used, namely PMMA and SAL 601, both showed 0.12 μm resolution capability in dense and large layouts patterning and also, under optimised exposure and development conditions, exhibited good exposure latitudes which were also evaluated for two different beam spot sizes. Furthermore, a study of development technique and effect of e-beam spot size indicated a marked dependence of ultimate resolution and exposure latitude on such parameters. A statistical analysis of 0.12 μm resolution SAL patterning on large chip dies (30 × 30 mm2) resulted in a dimensional control of 10 nm (3σ value).
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering