Sci-Tron has introduced a new negative tone e-beam resist with high etch selectivity.
The resist, called nEBL3, is flexible and adaptable for a number of market sectors. The resist can be used for direct-write lithography applications. The resist is also ideal for the production of next-generation EUV photomasks. Current e-beam resists have difficulties in terms of meeting the specifications for EUV masks or are difficult to use.
Based on a modular design, Sci-Tron’s heterometallic resist (HMR) technology enables new lithographic device architectures. The modular approach enables nEBL3 to be used with other solvents and developers. This in turn opens the door for manufacturers to incorporate the negative tone resist into their existing fabrication processes.
It also enables high etch selectivity in structures. “The etch selectivity to silicon achieved is so high that we have been studying 15nm thick films of nEBL3, spun from tert-butyl methyl ether (TBME) for high-resolution plasma etching,” said Scott Lewis, director and senior technical advisor at Sci-Tron.
With the resist, the company has demonstrated etch selectivity of >100:1 at a 15nm half-pitch. “However, we have achieved an etch selectivity of >60:1 even down to 8nm resolution,” Lewis said. “We believe that nEBL3 has the potential to become the benchmark negative tone resist to use for lithographers who need to fabricate narrow, deep features.”
Richard Winpenny, director and chief scientific officer at Sci-Tron, added: “nEBL3 is a production-ready negative tone resist as it stands, yet also a ‘launch-pad’ solution for any manufacturers seeking to leverage this technology in their production processes.”
To date, the company has tested its resists on Raith’s 5000+ e-beam lithography systems as well as their latest 5200 tool. The results are cited above. The work was verified at California Institute of Technology (Caltech) in the Kavli Nanoscience Institute.
Sci-Tron is also working with a III-V foundry on prototyping the latest GaN CMOS integrated circuits. The foundry is using the resists to pattern these devices.
The most recent results were achieved in an ongoing collaboration between Sci-Tron, the University of Manchester and the Kavli Nanoscience Institute at CalTech.
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Any persons or organisations wishing to find out more and arrange for purchase of commercial evaluation samples, contact Sci-Tron Limited at info@sci-tron.com
We would like to extend our thanks to Mark LaPedus for featuring Sci-Tron’s nEBL3 negative tone e-beam resist on the Semiconductor Engineering website (Manufacturing Bits, 8 June)
