Sub-50 nm feature sizes using positive tone molecular glass resists for EUV lithography

Chang, Shi; Ayothi, Ramakrishnan; Bratton, Daniel; Yang, Da; Felix, Nelson; Cao, Heidi B.; Deng, Hai; Ober, Christopher K.

doi:10.1039/b514065j

Cited by 81 publications

(77 citation statements)

References 24 publications

(35 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 90 ] In general the molecular glass resist has a well-defi ned small-molecule core that bears protected base-soluble groups (such as hydroxyls and carboxyls) as shown in Figure 21b . With this approach the core chemistry can vary from calix [4]resorcinarenes (ringlike), [91][92][93] branched phenolic groups, [ 94,95 ] and hexaphenolic groups (disklike). [ 96,97 ] Early approaches with molecular resists led to low glass-transition temperatures, however, such problems were resolved by increased hydrogen bonding functionality and the design of the core structure.…”

Section: Advances By Materials Structurementioning

confidence: 99%

Photoresist Latent and Developer Images as Probed by Neutron Reflectivity Methods

Prabhu¹,

Kang²,

VanderHart³

et al. 2010

Advanced Materials

View full text Add to dashboard Cite

Photoresist materials enable the fabrication of advanced integrated circuits with ever-decreasing feature sizes. As next-generation light sources are developed, using extreme ultraviolet light of wavelength 13.5 nm, these highly tuned formulations must meet strict image-fidelity criteria to maintain the expected performance gains from decreases in feature size. However, polymer photoresists appear to be reaching resolution limits and advancements in measurements of the in situ formed solid/solid and solid/liquid interface is necessary. This Review focuses on the chemical and physical structure of chemically amplified photoresists at the lithographic feature edge at length scales between 1 nm and 100 nm. Neutron reflectivity measurements provide insight into the nanometer-scale composition profiling of the chemical latent image at an ideal lithographic line-edge that separates optical resolution effects from materials processing effects. Four generations of advanced photoresist formulations were examined over the course of seven years to quantify photoresist/photoacid and photoresist/developer interactions on the fidelity of lithographic features. The outcome of these measurements complement traditional resist design criteria by providing the effects of the impacts of the photoresist and processing on the feature fidelity. These physical relations are also described in the context of novel resist architectures under consideration for next-generation photolithography with extreme-ultraviolet radiation.

show abstract

Section: Advances By Materials Structurementioning

confidence: 99%

Photoresist Latent and Developer Images as Probed by Neutron Reflectivity Methods

Prabhu¹,

Kang²,

VanderHart³

et al. 2010

Advanced Materials

View full text Add to dashboard Cite

show abstract

“…In 2006, Chang et al 34 reported a series of t-Boc-protected C-4-hydroxyphenyl-calix [4]resorcinarenes (Figure 6a) derivatives as positive-tone resists for EUV lithography. It was the first report on the calixarene-based resist for EUV lithography, and 30 nm positivetone patterns were achieved.…”

Section: Mg Resists Based On Cyclic Architecturesmentioning

confidence: 99%

In pursuit of Moore’s Law: polymer chemistry in action

Kosma

Giannelis³

et al. 2017

Polym J

View full text Add to dashboard Cite

We present a focused review of photoresist strategies that have been studied over the past few decades driven by the demands of Moore's law. Selected results are discussed with emphasis on the choice of photoresist chemistry depending on the particulars of each radiation type or patterning strategy, while we present special architectures of photoresists that have attracted a great interest in the semiconductor field. We adopt an approach that allows for easy comparison between the different photoresist categories and we include brief discussions of a number of important preparation and property issues pertaining to key characteristics affecting resist performance. Polymer Journal (2018) 50, 45-55; doi:10.1038/pj.2017.64; published online 1 November 2017Photoresists are a workhorse tool for the semiconductor industry; they enable creation of small-scale structures using continuously evolving strategies to form objects of the nanoscale dimensions are needed to stay on the technology path of Moore's law. Simply put, photoresists transfer information using a light-driven process that makes them (often a polymer) either more or less soluble in the exposed region of the film. As dimensions have changed, so too have the chemistry and materials sets used in lithography. Originally requiring critical features of microns, photoresists such as cyclized polyisoprene were used. 1 Subsequently, novolac photoresists were developed and formed a water-soluble exposed material, avoiding the need for organic solvents that swelled the photoresist during development while operating at a shorter wavelength than prior resists, thus enabling smaller, more uniform features. 2 The creation of novolac resists set up a trend in photoresist design: a water developable material, working at a shorter and shorter wavelength to enable a finer feature size and adjusted composition to maintain sufficient transparency for pattern formation. This approach has carried forward through several generations of photoresists built around the principle of chemical amplification.A team of researchers with expertise in photoresists, polymersupported chemistry and protein synthesis worked at the IBM Almaden Research (San Jose, CA, USA) to tackle a new challenge in photolithography: to develop a photoresist that needed very little radiation to cause the solubility change needed during the patterning step. 3 Their concern was that the mercury light source being used to create UV radiation was increasingly weak as shorter wavelengths were used. Hence, a new process was needed that made better use of the imaging radiation.By using acid catalysis driven by a proton created in a light-induced decomposition of a photoacid generator, a single photon was shown to initiate hundreds of reactions. The resulting chemical amplification caused by that single photon was shown to overcome the limited radiation present in light sources of the time. However, the process also did something else arguably more important; it enabled a solubility change from the oil-soluble polymer ...

show abstract

“…A key aim for the development of photoresists and associated processes is to simultaneously improve RLS. Many gains can be made by optimisation of resist formulations, although more disruptive technologies include the redesign of the resists and such approaches include: polymer bound PAG resists, [1][2][3][4][5][6][7] molecular glass resists [8][9][10][11][12][13][14][15][16] and chain scissioning resists. [17][18][19][20][21][22][23][24][25][26] In particular, polymer bound PAG resists have achieved a great deal of success as EUVL platforms, although improvements are still required for achieving the ITRS goals.…”

Section: Introductionmentioning

confidence: 99%

Extending the scope of poly(styrene)-block-poly(methyl methacrylate) for directed self-assembly

et al. 2014

View full text Add to dashboard Cite

Directed self-assembly (DSA) is a promising technique for extending conventional lithographic techniques by being able to print features with critical dimensions under 10 nm. The most widely studied block copolymer system is polystyreneblock-polymethyl methacrylate (PS-b-PMMA). The system is well understood in terms of its synthesis, properties and performance in DSA. However, PS-b-PMMA also has a number of limitations that impact on its performance and hence scope of application. The primary limitation is the low Flory-Huggins polymer-polymer interaction parameter (χ), which limits the size of features that can be printed by DSA. Another issue with block copolymers in general is that specific molecular weights need to be synthesized to achieve desired morphologies and feature sizes. We are exploring blending ionic liquid additiveswithPS-b-PMMAto increase the χ parameter. This allows smaller feature sizes to be accessed by PS-b-PMMA. Depending on the amount of additive it is also possible to tune the domain size and the morphology of the systems. These findings may expand the scope of PS-b-PMMA for DSA.

show abstract

Sub-50 nm feature sizes using positive tone molecular glass resists for EUV lithography

Cited by 81 publications

References 24 publications

Photoresist Latent and Developer Images as Probed by Neutron Reflectivity Methods

Photoresist Latent and Developer Images as Probed by Neutron Reflectivity Methods

In pursuit of Moore’s Law: polymer chemistry in action

Extending the scope of poly(styrene)-block-poly(methyl methacrylate) for directed self-assembly

Contact Info

Product

Resources

About