Multi-layer resist technology

The current technological competition for practical fabrication of 0.5 - 1.0 pm feature is in between photolithography and electron beam direct writing, and between single layer and multi-level resist. For less than 0.5 pm, the use of electron beam writing with multilevel resist will be inevitable. Further developments in electron resists from the standpoint of both resist chemistry and process development will be necessary to establish the electron beam lithography. 

Hearle JWS, Leech CM, Adeyefa A, Cork CR. Ballistic impact resistance of multi-layer textile fabrics. Manchester University of Manchester Institute of Science and Technology 1981. p. 33. 

Liu, C., Leyland, A., Bi, Q. et al. 2001. Corrosion resistance of multi-layered plasma-assisted physical vapour deposition TiN and CrN coatings. Surface and Coatings Technology 141 164-173. 

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