Scalability limits of Talbot lithography with plasma-based extreme ultraviolet sources

Abstract

Lithography has been faced with a challenge to bring resolution down to the 10-nm level. One of the promising approaches for such ultra-high-resolution printing is self-imaging Talbot lithography with extreme ultraviolet (EUV) radiation. However, as the size of structures on the mask approaches the wavelength of the radiation, diffraction influence needs to be evaluated precisely to estimate the achievable resolution and quality of the patterns. Here, the results of finite-difference time-domain simulations of the diffraction on EUV transmission masks in dependence to the period (pitch) of the mask are presented with the aim to determine the resolution that can be realistically achieved with the EUV Talbot lithography. The modeled experimental setup is utilizing partially coherent EUV radiation with the wavelength of 10.9 nm from Xe/Ar discharge plasma EUV source and Ni/Nb-based amplitude transmission mask. The results demonstrate that the method can be used to produce patterns with resolution down to 7.5-nm half-pitch with 2:1 mask demagnification utilizing achromatic Talbot effect and transverse electric (TE)-polarized light

Patterning of nanodot-arrays using EUV achromatic Talbot lithography at the Swiss Light Source and Shanghai Synchrotron Radiation Facility

“…The precision of the exposure area delimitation in the context of step-and-repeat exposures is limited by the precision of the sample stage. The minimum period of features patterned using ATL at PSI is 70 nm with 15 nm dot size [10], while the theoretical limit approaches 7.5 nm half-pitch using 10.9 nm EUV light [16].…”

Generation of circularly polarized radiation from a compact plasma-based extreme ultraviolet light source for tabletop X-ray magnetic circular dichroism studies

“…2 In interference lithography, the contrast between the highest and lowest intensity in the resist is considerably better with linearly polarized light compared to unpolarized light. 3 Another application of polarized EUV and soft X-ray radiation, magneto-optical polarization spectroscopy, [4][5][6] provides valuable information about magneto-optical constants and enables studies of element-and layer-selective magnetization. For magneto-optical spectroscopy, both linearly and circularly polarized light is required.…”

High-resolution proximity lithography for nano-optical components

“…Subsequently, many groups have contributed to the topic, focusing e.g. on extreme ultraviolet (EUV) Talbot lithography [140][141][142], Talbot immersion lithography [143], gray-scale lithography by self-imaging [144] and many more [145][146][147][148]. Beyond that, several approaches to overcome the limitations of Talbot lithography have been proposed meanwhile and will be discussed in the following paragraphs.…”