Atomic Layer Deposition Assisted Pattern Multiplication of Block Copolymer Lithography for 5 nm Scale Nanopatterning

Abstract

5-nm-scale line and hole patterning is demonstrated by synergistic integration of block copolymer (BCP) lithography with atomic layer deposition (ALD).While directed self-assembly of BCPs generates highly ordered line array or hexagonal dot array with the pattern periodicity of 28 nm and the minimum feature size of 14 nm, pattern density multiplication employing ALD successfully reduces the pattern periodicity down to 14 nm and minimum feature size down to 5 nm. Self-limiting ALD process enable the low temperature, conformal deposition of 5 nm thick spacer layer directly at the surface of organic BCP patterns. This ALD assisted pattern multiplication addresses the intrinsic thermodynamic limitations of low χ BCPs for sub-10-nm scale downscaling. Moreover, this approach offers a general strategy for scalable ultrafi ne nanopatterning without burden for multiple overlay control and high cost lithographic tools.

Atomic layer deposition for spacer defined double patterning of sub-10 nm titanium dioxide features

“…Atomic layer deposition (ALD) is particularly appropriate for the spacer fabrication [22,23] because it produces excellent conformity and uniformity without loading effect across an entire wafer [21]. ALD allows the formation of ultra-thin films with angstrom-level resolution by cyclical oxidation of a metal-organic precursor [24,25]. Control of the ALD parameters is instrumental in defining the feature size and frequency of the double patterned lines.…”

Multilayer block copolymer meshes by orthogonal self-assembly

“…Monolayers of block copolymer (BCP) microdomains made by templated self-assembly have been highly successful at producing both simple and complex two-dimensional (2D) patterns, for example, bends and junctions, as well as different morphologies on a single substrate 1 2 3 4 5 6 7 8 9 10 11 12 . Beyond 2D, reports have investigated BCP self-assembly in three dimensions (3D), such as in thin films and nanopores 13 14 15 16 17 18 .…”

Inductively coupled plasma nanoetching of atomic layer deposition alumina

“…ZEP resist gratings (g) were transferred into the alumina film (h), and the grating patterns were etched into the silicon (i). [26], chromium [27], and ALD alumina assisted pattern transfer of directed self-assembly (DSA) of block copolymers [17], [18]. Aspect ratios higher than 50 for sub-50 nm structures was reported [24], [25].…”

“…Wang and Goryll showed selectivity of PMMA resist over alumina be 5:1 using a pure BCl 3 plasma and a reactive ion etching instrument [16]. ALD alumina can also assist nanopattern transfer of directed self-assembly of block co-polymers with great fidelity [17], [18]. We were not able to find systematic studies of nanoscale ICP etch of ALD alumina, which is important if alumina must be used as an etch mask in the nanoscale.…”