93 research outputs found
Selective Solvent Induced Orientation Control of PS-PDMS Self-Assembly for Block Copolymer Nanolithography.
Substrate tolerant direct block copolymer nanolithography
Sub-20 nm block copolymer films directly applied on substrates and annealed in vapors of selective solvents significantly simplify the lithographic process.</p
Experimental demonstration of graphene plasmons working close to the near-infrared window
Due to strong mode-confinement, long propagation-distance, and unique
tunability, graphene plasmons have been widely explored in the mid-infrared and
terahertz windows. However, it remains a big challenge to push graphene
plasmons to shorter wavelengths in order to integrate graphene plasmon concepts
with existing mature technologies in the near-infrared region. We investigate
localized graphene plasmons supported by graphene nanodisks and experimentally
demonstrated graphene plasmon working at 2 {\mu}m with the aid of a fully
scalable block copolymer self-assembly method. Our results show a promising way
to promote graphene plasmons for both fundamental studies and potential
applications in the near-infrared window.Comment: 6 pages, 4 figures, a revised versio
Rapid, Brushless Self-assembly of a PS-b-PDMS Block Copolymer for Nanolithography
AbstractBlock copolymers (BCP) are highly promising self-assembling precursors for scalable nanolithography. Very regular BCP nanopatterns can be used as on-chip etch masks. The first step in the processing of BCP thin films is usually the chemical modification of the substrate surface, typically by grafting of a brush layer that renders the surface energy neutral relative to the constituent blocks. We provide here a first study on rapid, low temperature self-assembly of PS-b-PDMS (polystyrene-block-polydimethylsiloxane) on silicon substrates without a brush layer. We show that it forms line and antidot patterns after short solvo-thermal annealing. Unlike previous reports on this system, low temperature and short annealing time provide self-assembly in homogeneous thin films covering large substrate areas. This on-chip mask was then used for pattern transfer to the underlying silicon substrate. SEM (scanning electron microscope) images reveal silicon nanowires relative to the PDMS patterns of the BCP mask
Sub-15nm Silicon Lines Fabrication via PS-b-PDMS Block Copolymer Lithography
This paper describes the fabrication of nanodimensioned silicon structures on silicon wafers from thin films of a poly(styrene)-block-poly(dimethylsiloxane) (PS-b-PDMS) block copolymer (BCP) precursor self-assembling into cylindrical morphology in the bulk. The structure alignment of the PS-b-PDMS (33 k–17 k) was conditioned by applying solvent and solvothermal annealing techniques. BCP nanopatterns formed after the annealing process have been confirmed by scanning electron microscope (SEM) after removal of upper PDMS wetting layer by plasma etching. Silicon nanostructures were obtained by subsequent plasma etching to the underlying substrate by an anisotropic dry etching process. SEM images reveal the formation of silicon nanostructures, notably of sub-15 nm dimensions
Synthesis and systematic optical investigation of selective area droplet epitaxy of InAs/InP quantum dots assisted by block copolymer lithography
We report on the systematic investigation of the optical properties of a
selectively grown quantum dot gain material assisted by block-copolymer
lithography for potential applications in active optical devices operating in
the wavelength range around 1.55 um and above. We investigated a new type of
diblock copolymer PS-b-PDMS (polystyrene-block-polydimethylsiloxane) for the
fabrication of silicon oxycarbide hard mask for selective area epitaxy of
InAs/InP quantum dots. An array of InAs/InP quantum dots was selectively grown
via droplet epitaxy. Our detailed investigation of the quantum dot carrier
dynamics in the 10-300 K temperature range indicates the presence of a density
of states located within the InP bandgap in the vicinity of quantum dots. Those
defects have a substantial impact on the optical properties of quantum dots.Comment: 11 pages, 5 figures, 1 tabl
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