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A new class of electron bean negative tone resist materials has been developed based on heterometallic rings. The initial resist performance demonstrates a resolution of 15 nm half-pitch but at the expense of a low sensitivity. To improve sensitivity a 3D Monte Carlo simulation is used that utilizes a secondary and Auger electron generation model. The simulation suggests that the sensitivity can be dramatically improved while maintaining high resolution by incorporating appropriate chemical functionality around the metal–organic core. The new resists designs based on the simulation have the increased sensitivity expected and illustrate the value of the simulation approach.

An approach is presented for nanoscale patterning of zinc oxide (ZnO) using electron beam (e-beam) lithography for future nanoelectronic devices and for hard lithographic masks. Zinc acetate (Zn4O(...

We show that by design we can create a new resist materials for electron beam lithography, based on a supramolecular assembly. The initial studies show that via this supramolecular approach high resolution structures can be written which showunprecedented selectivity when exposed to etch conditions involving plasmas.

Field-emission devices are promising candidates to replace silicon fin field-effect transistors as next-generation nanoelectronic components. For these devices to be adopted, nanoscale field emitters with nanoscale gaps between them need to be fabricated, requiring the transfer of, for example, sub-10 nm patterns with a sub-20 nm pitch to substrates like silicon and tungsten. New resist materials must therefore be developed that exhibit the properties of sub-10 nm resolution and high dry etch resistance. A negative tone, metal–organic resist is presented here. It can be patterned to produce sub-10 nm features when exposed to helium ion beam lithography at line doses on the order of tens of picocoulombs per centimeter. The resist was used to create 5 nm wide, continuous, discrete lines spaced on a 16 nm pitch in silicon and 6 nm wide lines on an 18 nm pitch in tungsten, with line edge roughness of 3 nm. After the lithographic exposure, the resist demonstrates high resistance to silicon and tungsten dry etch conditions (SF_6 and C_4F_8 plasma), allowing the pattern to be transferred to the underlying substrates. The resist’s etch selectivity for silicon and tungsten was measured to be 6.2:1 and 5.6:1, respectively; this allowed 3 to 4 nm thick resist films to yield structures that were 21 and 19 nm tall, respectively, while both maintained a sub-10 nm width on a sub-20 nm pitch.

A new class of resist materials has been developed that is based on a family of heterometallic rings. The work is founded on a Monte Carlo simulation that utilizes a secondary and Auger electron generation model to design resist materials for high resolution electron beam lithography. The resist reduces the scattering of incident electrons to obtain line structures that have a width of 15 nm on a 40 nm pitch. This comes at the expense of lowering the sensitivity of the resist, which results in the need for large exposure doses. Low sensitivity can be dramatically improved by incorporating appropriate functional alkene groups around the metal-organic core, for example by replacing the pivalate component with a methacrylate molecule. This increases the resist sensitivity by a factor of 22.6 and demonstrates strong agreement between the Monte Carlo simulation and the experimental results. After the exposure and development processes, what remains of the resist material is a metal-oxide that is extremely resistant to silicon dry etch conditions; the etch selectivity has been measured to be 61:1.