Polystyrene negative resist for high-resolution electron beam lithography

• Published in: Nanoscale research letters 2011-07, Vol.6 (1), p.446-446, Article 446
• Main Authors: Ma, Siqi, Con, Celal, Yavuz, Mustafa, Cui, Bo
• Format: Article
• Language: English
• Subjects: Chemistry and Materials Science; Materials Science; Molecular Medicine; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering
• ISSN: 1556-276X; 1931-7573; 1556-276X
• DOI: 10.1186/1556-276X-6-446

We studied the exposure behavior of low molecular weight polystyrene as a negative tone electron beam lithography (EBL) resist, with the goal of finding the ultimate achievable resolution. It demonstrated fairly well-defined patterning of a 20-nm period line array and a 15-nm period dot array, which are the densest patterns ever achieved using organic EBL resists. Such dense patterns can be achieved both at 20 and 5 keV beam energies using different developers. In addition to its ultra-high resolution capability, polystyrene is a simple and low-cost resist with easy process control and practically unlimited shelf life. It is also considerably more resistant to dry etching than PMMA. With a low sensitivity, it would find applications where negative resist is desired and throughput is not a major concern.