Sub-100 nm structuring of indium-tin-oxide thin films by sub-15 femtosecond pulsed near-infrared laser light

Afshar, Maziar; Straub, Martin; Voellm, Henning; Feili, Dara; Koenig, Karsten; Seidel, H.

doi:10.1364/ol.37.000563

Cited by 21 publications

(12 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Samples termed ITO-2 were produced with 2 sccm oxygen flow (total flow 60 sccm, chamber pressure 0.003 mbar). The electrical and optical properties of ITO as n-type wide-band gap semiconductor (band gap 3.5 -4.1 eV [8,14,15]) strongly depend on the oxygen content [16]. A specific resistivity of ITO-2 of 3.9 x 10 -4 Ω cm was determined by the van-der-Pauw method in accordance with earlier experiments [16].…”

Section: Ito Film Deposition and Ma-n Photoresist Coatingsupporting

confidence: 59%

See 1 more Smart Citation

Generation of laser-induced periodic surface structures in indium-tin-oxide thin films and two-photon lithography of ma-N photoresist by sub-15 femtosecond laser microscopy for liquid crystal cell application

et al. 2015

Self Cite

View full text Add to dashboard Cite

Indium-tin-oxide (ITO) is a widely used electrode material for liquid crystal cell applications because of its transparency in the visible spectral range and its high electrical conductivity. Important examples of applications are displays and optical phase modulators. We report on subwavelength periodic structuring and precise laser cutting of 150 nm thick indium-tin-oxide films on glass substrates, which were deposited by magnetron reactive DC-sputtering from an indiumtin target in a low-pressure oxygen atmosphere. In order to obtain nanostructured electrodes laser-induced periodic surface structures with a period of approximately 100 nm were generated using tightly focused high-repetition rate sub-15 femtosecond pulsed Ti:sapphire laser light, which was scanned across the sample by galvanometric mirrors. Three-dimensional spacers were produced by multiphoton photopolymerization in ma-N 2410 negative-tone photoresist spin-coated on top of the ITO layers. The nanostructured electrodes were aligned in parallel to set up an electrically switchable nematic liquid crystal cell.

show abstract

Section: Ito Film Deposition and Ma-n Photoresist Coatingsupporting

confidence: 59%

“…Due to the ITO-2 absorption edge wavelength of 420 nm multiphoton excitation is expected to dominate the ablation process [16]. Operating extremely close to the ablation threshold, tiny rifts perpendicular to the laser polarization appeared at fairly regular space intervals.…”

Section: Nanopatterning and Cutting Of Ito Thin Film Electrodes By Sumentioning

confidence: 99%

Generation of laser-induced periodic surface structures in indium-tin-oxide thin films and two-photon lithography of ma-N photoresist by sub-15 femtosecond laser microscopy for liquid crystal cell application

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ablative LIPSS aligned perpendicular to the laser beam polarization (⊥-LIPSS) and periods as small as ≈λ/15 have been observed in films irradiated with high repetition rate, fs laser pulses at 800 nm at extremely slow scanning speeds ( ≈10´s µm s −1 ). [21] At a much lower repetition rate, Wang et al [22] observed periodic arrangements of nanolines and nanodots with longer, multimodal period structures (Λ ≈ λ, λ/2 and λ/4) in samples statically irradiated at the same wavelength. More recently, femtosecond-laser pulses at 1030 nm have been used to generate ablative ⊥-LIPSS with a very small period [16] (Λ ≈ λ/9) using a slow beam scanning speed.…”

Section: Introductionmentioning

confidence: 99%

Anisotropic Resistivity Surfaces Produced in ITO Films by Laser‐Induced Nanoscale Self‐organization

López‐Santos

Puerto

Siegel

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

emitting diodes, flat panel displays, etc.) and energy harvesting (photovoltaics, low emissivity coatings, etc.). [1] They are produced by creating electron degeneracy in a wide bandgap oxide either introducing non-stoichiometry (solid solutions) and/ or appropriate dopants, like Sb or F. [2] This is usually achieved in mixtures of different Group III oxides with metal oxides where the metal can be a part of the semiconductor oxide or act as dopant. This leads to different families of TCOs including AZO (aluminum zinc oxide), IZO (indium zinc oxide), ITO (indium tin oxide), GZO (gallium zinc oxide), and so on. Among them ITO (typically ≈90% wt% In 2 O 3 + 10 wt% SnO 2) plays a key role, especially to produce transparent conductive electrodes (TCEs) in flat-panel displays. Regarding the structuring of ITO films, although wet chemical etching is suitable for producing micron-width electrodes, the need for rapid, and mask-less patterning of large areas led to investigation of the use of laser structuring already in the late 90s. [3] A similarly important application of lasers for processing TCOs is their use for sintering spin-coated films formed by nanoparticles, especially on flexible substrates. [4-6] However, the peculiarities of its absorption spectrum and the regular use of transparent substrates impose limitations in Highly anisotropic resistivity surfaces are produced in indium tin oxide (ITO) films by nanoscale self-organization upon irradiation with a fs-laser beam operating at 1030 nm. Anisotropy is caused by the formation of laser-induced periodic surface structures (LIPSS) extended over cm-sized regions. Two types of optimized structures are observed. At high fluence, nearly complete ablation at the valleys of the LIPSS and strong ablation at their ridges lead to an insulating structure in the direction transverse to the LIPSS and conductive in the longitudinal one. A strong diminution of In content in the remaining material is then observed, leading to a longitudinal resistivity ρ L ≈ 1.0 Ω•cm. At a lower fluence, the material at the LIPSS ridges remains essentially unmodified while partial ablation is observed at the valleys. The structures show a longitudinal conductivity two times higher than the transverse one, and a resistivity similar to that of the pristine ITO film (ρ ≈ 5 × 10 −4 Ω•cm). A thorough characterization of these transparent structures is presented and discussed. The compositional changes induced as laser pulses accumulate, condition the LIPSS evolution and thus the result of the structuring process. Strategies to further improve the achieved anisotropic resistivity results are also provided.

show abstract

“…A great many research works have been done in this field in past several decades [2][3][4][5][6][7][8][9][10][11][12] . For instances, nanogratings were produced by radial and azimuthal laser polarization modes [13] , pyramid-like spikes in a single crystal superalloy upon irradiation with picosecond laser pulses were investigated [14] .…”

Section: Introductionmentioning

confidence: 99%

Raman spectroscopy and periodic surface structures of Mg:ZnO thin film fabricated by femtosecond laser pulses

Wang

Cheng

et al. 2014

Nanophotonics V

View full text Add to dashboard Cite

Mg doped ZnO thin films were prepared by magnetron sputtering and were irradiated by linearly polarized femtosecond laser pulse. Scanning electron microscopy (SEM) characterizations illustrated that regularly arranged nanoripples appeared on the ablation area with the period perpendicular to the polarization direction in the range of 250 nm~570 nm, but parallel to the polarization direction in the range of 2.2 μm~2.5 μm. The redshift of Raman peaks was observed at the central ablation area of the nanoripples, while, both blueshift and redshift were found at the edge area, which could be ascribed to the defects as well as the nanoripple structure.

show abstract

Sub-100 nm structuring of indium-tin-oxide thin films by sub-15 femtosecond pulsed near-infrared laser light

Cited by 21 publications

References 20 publications

Generation of laser-induced periodic surface structures in indium-tin-oxide thin films and two-photon lithography of ma-N photoresist by sub-15 femtosecond laser microscopy for liquid crystal cell application

Generation of laser-induced periodic surface structures in indium-tin-oxide thin films and two-photon lithography of ma-N photoresist by sub-15 femtosecond laser microscopy for liquid crystal cell application

Anisotropic Resistivity Surfaces Produced in ITO Films by Laser‐Induced Nanoscale Self‐organization

Raman spectroscopy and periodic surface structures of Mg:ZnO thin film fabricated by femtosecond laser pulses

Contact Info

Product

Resources

About