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sÜss microtec inc faculty summaries and technology abstracts for more information contact sonia kim phd manager for marketing and industry partnerships innovation and new ventures office 1800 sherman ave suite 504 evanston il 60201 main 847 467-2097 direct 847 467-0446 email invo@northwestern.edu or sonia.kim@northwestern.edu 1

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contents semiconductors related applications mark hersam phd 3 bridge enhanced nanoscale impedance microscopy 3 atomic force electroluminescence microscopy 4 cryogenic variable temperature scanning tunneling microscope 5 seng-tiong ho phd 6 low-voltage organic electro-optic modulators using transparent conducting oxides as electrodes 6 tobin marks phd 7 catalytic synthesis of high energy density nanocomposite dielectric materials 7 nanoscale self-assembled organic dielectrics for ultra-low voltage high-speed electronic devices 8 enhanced performance of blue light emitting polymer diodes via anode modification 9 new hole transport layer materials for polymer light emitting diodes 10 novel tfb:tpdsi2 interfacial layer with improved power conversion efficiency for organic photovoltaic cells 11 chad mirkin phd 12 on-wire lithography 12 beam pen lithography 13 teri odom phd 14 programmable soft lithography solvent-assisted nanoscale embossing 14 novel techniques for the production of large-area subwavelength hole arrays 15 a compact and portable benchtop photolithography system 16 mesoscale metallic pyramids with nanoscale tips 17 bruce wessels phd 18 thin uniform layer of epitaxial oxide on si substrates for microelectronic and microphotonic devices 18 batio3 thin film waveguide modulator with an increased electrooptic coefficient and wider bandwidth 19 semiconductor magnetodiodes for use in magnetic field sensors 20 highly efficient broadband second harmonic generation using batio3 thin film waveguides 21 2

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mark hersam phd professor in materials science and engineering the hersam laboratory develops chemically refined nanomaterials with unprecedented control over structure properties and surface chemistry of particular interest are carbon-based nanomaterials including carbon nanotubes and graphene due to their diverse range of applications in electronics optoelectronics photovoltaics batteries biomedical imaging and drug delivery in addition to synthesis and fabrication of nanomaterials and devices the hersam laboratory also develops scanning probe characterization methods with spatial resolution down to the atomic scale specific examples include cryogenic variable temperature ultra-high vacuum scanning tunneling microscopy nanoscale impedance microscopy atomic force electroluminescence microscopy and atomic force photovoltaic microscopy bridge enhanced nanoscale impedance microscopy be-nim nu 2005-060 inventors mark hersam liam pingree abstract northwestern scientists have developed a conductive atomic force microscopy cafm adjunct that is capable of quantitatively measuring the magnitude and phase of alternating current flow through the tip/sample junction with a five order of magnitude improvement in sensitivity this technology called bridge enhanced nanoscale impedance microscopy be-nim offers significant improvement in sensitivity and spatial resolution for the study of electronic behavior in nanomaterials and biological samples while macroscopic impedance spectroscopy techniques have been employed to characterize alternating current charge transport for a variety of materials systems and devices they only reveal an ensemble average of the underlying contributions of individual pathways defects film thickness variations electrochemical reactions and failure mechanisms scanning probe impedance measurement techniques based on the conductive atomic force microscope cafm has enabled probing current flow and resistivity variations on conductive surfaces with nanoscale spatial resolution however fringe capacitance 1-100 picof between the sample and the probe imposes a serious detection limit in an effort to improve the sensitivity of nanoscale impedance microscopy be-nim offers a variable resistor/capacitor rc bridge circuit to cancel the spurious contribution to the ac current flow caused by fringe capacitance this addition significantly improves the detection limit of nim by at least five orders of magnitude enabling the detection of impedance values that are typical for many nanostructures nano-electrochemical cells and biological systems applications study of electrical properties of nanomaterials and biological samples advantages greater spatial resolution greater sensitivity ip status issued us patent no 7,705,617 3

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atomic force electroluminescence microscopy nu 2004-050 inventors mark hersam liam pingree abstract northwestern scientists have developed a new atomic force electroluminescence microscopy afem technology that is capable of gathering simultaneous topographical current and electroluminescence information through a commercially available conductive afm tip this technology characterizes individual bottom-emitting opto-electronic devices such as light-emitting diodes and electroluminescent devices at a resolution of 10 nm it has a particularly significant impact on the application of organic light-emitting diodes oleds in inexpensive large area high brightness and flexible color displays spatial mapping and correlation of topology current and electroluminescence characteristics of operating oleds are critical to achieve oled miniaturization for high density display by incorporating collection optics and photon detectors afem enables the resulting electroluminescence to be spatially correlated with tip position and nanometer scale mapping applications high density flexible color displays characterization of electroluminescence from semiconducting nanowires nanotubes and submicron optoelectronic devices advantages advanced operation increased light sensitivity greater resolution electroluminescence with nanometer spatial resolution ability to measure current input and emission spectroscopy publications pingree lsc hersam mc kern mm scott bj and marks tj 2004 spatially-resolved electroluminescence of operating organic light-emitting diodes using conductive atomic force microscopy applied physics letters 85 344-346 doi:10.1063/1.1765206 ip status issued us patent no 7,358,490 4

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cryogenic variable temperature scanning tunneling microscope nu 2004-108 inventors edward foley mark hersam abstract northwestern researchers have developed and designed a robust instrument that is capable of high atomic resolution at 8.2 to 300k critical for single molecule surface studies an essential design problem with current scanning tunneling microscopy is inadequate coupling to the cryogen to maintain a stable low temperature while being sufficiently decoupled from any source of environmental vibration this instrument utilizes the ease of use and thermal stability of a dual thermal shield continuous flow cryostat cooling system and the atomic resolution fcl capability of the stm scanner and controls present innovations include a shapal-m® aluminum nitride ceramic used for heat-sinking electrical isolation a beryllium copper sample holder to improve platform durability and thermal properties and use of titanium nitride coated platform rails to enhance inertial translation of the sample holder at cryogenic temperatures by varying the cryogen flow rate and actively heating the thermal shields the stm may be operated at any temperature from 8.2 to 300 k the design allows for dosing of samples with an ex situ source through a variable leak valve or with an in situ evaporation/sublimation module the system affords excellent drift stability 0.008 a/min tip-sample spacing 8.2 k which was unchanged at sustained background acoustic noise levels up to 68 db in addition shuttered sapphire windows allow direct optical access of the tip-sample junction at cryogenic temperatures atomic resolution fcl on hydrogen passivated si100 surfaces and cryogenic stm studies of individual molecules on degenerately doped silicon surfaces at cryogenic temperatures have been demonstrated with the device applications atomic microscopy at cryogenic temperatures advantages atomic resolution at cryogenic temperatures excellent thermal insulation superior drift stability stable vibrational operation direct optical access to the tip-sample interface and direct line-of-sight dosing of the sample publications foley et yoder nl guisinger np and hersam mc 2004 cryogenic variable temperature ultrahigh vacuum scanning tunneling microscope for single molecule studies on silicon surfaces review of scientific instruments 75 5280-5287 ip status issued us patent no 7,414,250 5

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seng-tiong ho phd professor of electronical and computer engineering the ho lab is 1 nanophotonics nanoscale lasers microring resonators photonic bandgap structures and wavelength mux/demux 2 optical communications devices for dwdm network applications 3 photonics integration high-density integration of iii-v optoelectronic and photonic devices 4 organic photonics self-assembly organic eo modulators and organic light-emitting devices 5 photonic materials research thin-film electro-optic modulators transparent conducting oxides 6 heterogeneous photonics integrated photonic devices utilizing cross-platform technologies such as optical mems 7 ultrafast nonlinear photonics ultrafast low-power all-optical wavelength converters routers switches and logic gates 8 micro-optics micro-optical lenses and silicon optical bench 9 device simulation simulation of optoelectronic and all-optical devices 10 quantum optics generation of quantum states of light low-voltage organic electro-optic modulators using transparent conducting oxides as electrodes nu 2003-080 inventors seng-tiong ho jing ma tobin marks guoyang xu abstract efforts to achieve lower switching voltages in modulators include the synthesis of higher electro-optic eo coefficient materials and the use of new device configurations however optimal properties have yet to be realized to address this researchers at northwestern university have employed transparent conducting oxides tco as device electrode materials which provide low optical loss and adjustable conductivity compared to metallic electrodes thin film nonlinear eo materials inserted directly between the tco electrodes eliminates additional voltage drop from the top and bottom claddings and increase the electric modulation field of the eo material this in turn leads to a significant reduction in modulator switching voltage resulting in 3-4 x greater electric field and 3-4 x lower switching voltage compared to conventional modulators modulators fabricated with transparent conducting oxide tco electrodes operate at significantly lower switching voltages than conventional devices these properties promise significant increases in modulation frequency which is essential for high speed optoelectronic and photonic applications application novel electro-optic modulator using transparent conducting oxide electrodes advantages leads to a 3-4x greater electric field and lower switching voltage compared to conventional modulators ip status issued us patent no 7,835,597 6

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tobin marks phd professor of chemistry and materials science and engineering prof marks lab is interested in synthetic organo-f-element and early-transition metal organometallic chemistry polymer chemistry materials chemistry homogeneous and heterogeneous catalysis moleculebased photonic materials superconductivity metal-organic chemical vapor deposition and biological aspects of transition metal chemistry catalytic synthesis of high energy density nanocomposite dielectric materials nu 2006-136 inventors sara dibenedetto neng guo mike lanagan tobin marks abstract future pulsed-power capacitors will require dielectric materials having very large energy densities with operating voltages 10 kv the operating characteristics of current state-of-the-art pulsed-power capacitors which utilize either ceramics or polymers as dielectric materials fall significantly short of this goal to address this researchers at northwestern university have developed nanocomposites that combine inorganic constituents and polymer matrices these new materials are formed via in situ propylene polymerization using a metallocene catalyst supported on ferroelectric oxide nanoparticles physical characterization has established that the nanoparticles are uniformly dispersed in a highly isotactic polypropylene matrix importantly these new nanocomposites have proven to be excellent insulators with energy densities comparable or exceeding values reported for ceramic polymer and composite dielectrics these exciting new nanocomposites promise a new family of dielectric materials for future high energy capacitor applications application high energy storage in capacitor and insulator applications advantages combination of inorganic and polymeric materials energy densities exceed current ceramic or polymer-based insulators significant potential for future high-energy capacitor applications publications guo n dibenedetto sa kwon dk wang l russell mt lanagan mt facchetti a marks tj 2007 supported metallocene catalysis for in situ synthesis of high energy density metal oxide nanocomposites journal of the american chemical society 129 766-767 guo n dibenedetto sa tewari p lanagan mt ratner ma marks tj 2010 nanoparticle size shape and interfacial effects on leakage current density permittivity and breakdown strength of metal oxide polyolefin nanocomposites experiment and theory chemistry of materials 22 1567-1578 li z fredin la tewari p dibenedetto sa lanagan mt ratner ma marks tj 2010 in situ catalytic encapsulation of core-shell nanoparticles having variable shell thickness dielectric and energy storage properties of highpermittivity metal oxide nanocomposites chemistry of materials 22 5154-5164 ip status patent applications have been filed 7

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nanoscale self-assembled organic dielectrics for ultra-low voltage high-speed electronic devices nu 2004-062 inventors antonio facchetti tobin marks myung-han yoon abstract northwestern researchers have developed extremely thin nanostructurally ordered pinhole-free ultra-highcapacitance/low leakage organic dielectrics that are fabricated with self-assembling siloxane current organic thin-film transistors otfts are based on -electron materials and have been extensively investigated for applications where current inorganic semiconductors cannot be employed a variety of otfts employing p-type and n-type organic semiconductors have been produced however typical biases that are required to achieve acceptable performance with conventional dielectric materials silicon oxide polymers etc are too high for practical use northwestern investigators have developed a solution phase self-assembly process that produces nanoscopic high-ci organic dielectrics which is critical to producing low-bias and low-leakage otfts in their process they utilize self-assembled a difunctional hydrocarbon chains cl 3sich28sicl3 in conjunction with octachlorotrisiloxane capping layers which produces an oriented robust multilayer conformal polysiloxane dielectric coating with minimal defects using this technology they generate devices with 2.3-5.5nm dielectric layer thickness on silicon and ito substrates the maximum capacitances are 385-710 nf/cm² at 10² hz which is significantly greater than 5-10 nf/cm² for conventional 300 nm sio2 the otfts constructed with the nanoinsulators also exhibit threshold voltages 1-9 of similar devices prepared with sio2 dielectric these nanostructured organic dielectrics can be incorporated into large tft structures having a variety of substrates and organic semiconductors tft response achieved at low operational biases offers potential for a range of lowpower and high-frequency electronic applications applications low-cost electronic devices flexible displays advantages self-assembly process thin-ordered nanostructures ultra-high capacitance/low leakage minimal defects publications dibenedetto s facchett a ratner ma marks tj 2009 molecular self-assembled monolayers and multilayers as gate dielectrics for organic thin film transistor applications advanced materials 21 1407-1433 facchetti a marks tj 2009 self-assembled nanodielectrics sand for unconventional electronics sigma-aldrich material matters 4 64-67 marks tj 2010 materials for organic and hybrid inorganic/organic electronics mrs bulletin 35 1018-1027 ip status issued us patent no 7,679,079 8

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enhanced performance of blue light emitting polymer diodes via anode modification nu 2002-103 inventors qinglan huang tobin marks he yan abstract researchers at northwestern university invented a process that significantly improves blue polymer light emitting diode pled performance efficiency and stability despite the increasing interest in polymer light emitting diodes for a wide range of display applications few efficient blue pleds have been reported blue pled devices generally require anode coating with a conductive polymer hole transport layer htl which can adversely impact device fabrication useful spectral range performance and stability this invention replaces the conductive polymer with an ultra-thin siloxane-derivative that enhances the ito anode htl interface thus simplifying the construction of the device as well as significantly improving pled performance efficiency and stability applications pfo-based blue pled device displays advantages simple device design and fabrication ultra-thin self-assembling anode interlayer elimination of spin coated doped conductive polymer hole transport layers enhancement of pled performance and stability negligible visible region absorption eliminates need for pedot-pss layer publications yan h huang q scott bj marks tj 2004 a polymer blend approach to fabricating the hole transport layer for polymer light-emitting diodes applied physics letters 84 3873-3875 yan h scott bj kern mm huang q marks tj 2004 enhanced polymer light-emitting diode performance using a crosslinked network electron-blocking interlayer advanced materials 16 1948-1953 yan h huang q cui j veinot jgc kern m marks tj 2003 enhancing the performance of blue polymer lightemitting diodes pled via anode modification with a self-assembled monolayer polymeric materials science and engineering 89 208-209 huang q evmenenko ga li j dutta p marks tj 2007 triarylamine siloxane anode functionalization/hole injection layers in high efficiency/high luminance small-molecule green-and blue-emitting organic lightemitting diodes journal of applied physics 101 093101-093113 veinot jgc marks tj 2005 toward the ideal organic light-emitting diode the versatility and utility of interfacial tailoring by siloxane self-assembly accounts of chemical research 38 632-643 ip status issued u.s patent no 6,939,625 9

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new hole transport layer materials for polymer light emitting diodes nu 2003-071 inventors qinglan huang tobin j marks he yan abstract northwestern researchers invented a new hole transport system for polymer light emitting diodes pleds with negligible visible light absorption stability to ito solvent resistance and tunable electronic properties pleds are of increasing interest in a wide range of display applications however conventional hole transport layer poly3,4ethylenedioxythiophene polystryenesulfonate pedot-pss devices exhibit significant visible light absorption and ito interface instability by cross-linking siloxane-derivatized hole-transport material tpd-si2 with hole transporting or insulating polymers the investigators address the above limitations further spin coating a tpdsi2/tfb blend on ito with thermal curing not only creates a strongly adherent cross-linked network but further provides an efficient hold transport layer that is stable to subsequent solvent coating operations applications displays pled fabrication advantages superior pled performance and efficiency enhanced device life solvent resistance ito interface stability minimal visible light absorption ability to customize specific electronic properties of emissive layer polymer publications yan h huang q scott bj marks tj 2004 a polymer blend approach to fabricating the hole transport layer for polymer light-emitting diodes applied physics letters 84 3873-3875 yan h scott bj kern mm huang q marks tj 2004 enhanced polymer light-emitting diode performance using a crosslinked network electron-blocking interlayer advanced materials 16 1948-1953 yan h huang q cui j veinot jgc kern m marks tj 2003 enhancing the performance of blue polymer lightemitting diodes pled via anode modification with a self-assembled monolayer polymeric materials science and engineering 89 208-209 huang q evmenenko ga li j dutta p marks tj 2007 triarylamine siloxane anode functionalization/hole injection layers in high efficiency/high luminance small-molecule green-and blue-emitting organic lightemitting diodes journal of applied physics 101 093101-093113 veinot jgc marks tj 2005 toward the ideal organic light-emitting diode the versatility and utility of interfacial tailoring by siloxane self-assembly accounts of chemical research 38 632-643 li j marks tj 2008 air-stable cross-linkable hole-injecting/transporting interlayers for improved charge injection in organic light-emitting diodes chemical materials 20 4873-4882 ip status issued u.s patent no 7,449,509 10

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novel tfb:tpdsi2 interfacial layer with improved power conversion efficiency for organic photovoltaic cells nu 2007-121 inventors alexander hains tobin marks abstract northwestern researchers have developed a new interfacial hole transport/electron-blocking layer for organic photovoltaics this technology obviates the need for the commonly employed pedot:pss layer and significantly improves the performance of mdmo-ppv:pcbm bulk heterojunction bhj solar cells while organic photovoltaics opv offer advantages over traditional inorganic photovoltaic cells including fabrication on lightweight flexible substrates and use of lower cost spin-coating and printing processes it lacks sufficient power conversion efficiency for commercial use this invention enhances bhj solar cell efficiency by addressing several areas critical to device performance a unique tfb:tpdsi2 blend spin-coated from an organic solvent and air cured to form a covalently bonded film on ito provides this function the cured material is transparent above 400 nm resists solvent attack in subsequent processing and retains adhesion above 60°c importantly the interlayer components possess aligned energy levels which permits holes to travel efficiently to the anode while preventing electron leakage this feature results in a vast improvement in power conversion efficiency this unique combination of interlayer properties provides a basis for significantly improved bhj solar cell devices applications organic photovoltaics solar cells advantages increased power conversion efficiency enhanced device stability retains robust ito adhesion eliminates use of pedot:pss publications hains aw martinson abf irwin md yan h marks tj 2007 bulk-heterojunction organic solar cells interfacial engineering routes to increased open-circuit voltage and power conversion efficiency polymeric materials science and engineering 96 814 hains aw marks tj 2008 high-efficiency hole extraction/electron-blocking layer to replace poly 3,4ethylenedioxythiophene poly styrene sulfonate pedot:pss in bulk-heterojunction polymer solar cells applied physics letters 92 023504 hains aw liu j martinson abf irwin md marks tj 2010 anode interfacial tuning via electron-blocking/holetransport layers and indium tin oxide surface treatment in bulk-heterojunction organic photovoltaic cells advanced functional materials 20 595-606 hains aw ramanan c irwin md liu j wasielewski mr marks tj 2010 designed bithiophene-based interfacial layer for high-efficiency bulk-heterojunction organic photovoltaic cells importance of interfacial energy level matching acs applied materials and interfaces 2 175-185 ip status a patent application has been filed 11

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chad mirkin phd professor of chemistry materials science and engineering dr chad mirkin is the director of the international institute for nanotechnology and the george b rathmann professor of chemistry chemical and biological engineering biomedical engineering materials science and engineering and medicine at northwestern university currently dr mirkin is listed as the most cited chemist in the world with the second highest impact factor and the top most cited nanomedicine researcher in the world in addition he is currently a member of president obama s council of advisors for science and technology his works spans a variety of disciplines on-wire lithography nu 2005-022 inventors ling huang chad mirkin sungho park lidong qin abstract northwestern researchers have developed a novel fabrication method called on-wire lithography owl which provides an unparalleled ability to make gapped nanowires and nanodisks for numerous applications it alters the composition length spacing and thickness of the nanowire with exquisite control the owl method first involves the formation of multilayered nanowires in a porous template the nanowires are then dispersed onto a substrate onto which a backing is deposited metals semiconductors or polymers may be deposited electrochemically within the linear pores the nanowires are sonicated with the backing off of the substrate and the sacrificial material is etched to provide the gapped nanowire etching chemistry can also be employed to selectively dissolve certain segments while the backing maintains spacing between domains while owl relies on template synthesis it utilizes new innovations enabling superior control of architecture and provides access to a myriad of architectures including segmented disk arrays of dimers trimers tetramers pentamers or nanogapped wires with a precisely controlled intersegment spacing as small as 2.5 nm applications coatings catalysis photovoltaics sensing diagnostics therapeutics advantages high-throughput synthetic method ability to create myriad of architectures precise control of intersegment spacing as small as 2.5nm publications braunschweig ab schmucker al wei wd mirkin ca 2010 nanostructures enabled by on-wire lithography owl chemical physics letters 486 89-98 ip status issued us patent no 7,422,696 12

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beam pen lithography nu 2008-173 inventors fengwei huo chad mirkin gengfeng zheng abstract northwestern researchers have developed a novel high-throughput form of optical nanolithography called beam pen lithography bpl which uses an array of near-field scanning optical microscopy nsom pens for nanoscale optical lithography with a programmable direct-write manner this technology addresses the many shortcomings of existing lithography techniques which include an inability to change designs frequently slow speed low throughput diffraction and resolution limits bpl merges the sub-100 nm resolution of nsom lithography and high throughput low cost properties of polymer pen lithography which is a direct-write method that delivers collections of ink molecules in a positive printing mode with high throughput high registration and low cost applications lithography for integrated circuits medical diagnostics and optoelectronics advantages high throughput high efficiency and fidelity high registration low cost publications huo f zheng g liao x giam lr cha ji chen x shim w and mirkin ca 2010 beam pen lithography nature nanotechnology 5 637­640 ip status a patent application has been filed this ip is available as a non-exclusive license 13

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teri odom phd professor of chemistry and materials science and engineering the odom laboratory develops large-area nanoscale fabrication tools that can be used to create multi-scale patterns from the sub-100 nm to wafer scales these methods rely on elastomer masks and molds to define nanoscale patterns on a wide range of substrates on soft substrates such as thermoplastic materials these patterns can be manipulated with independent control over feature size shape and lattice symmetry on hard substrates such as silicon wafers these patterns can be transferred into a wide variety of metal nanostructures discrete three-dimensional nanoparticles and continuous films of metal gratings and nanohole arrays are useful for a diverse range of applications including chemical and biological sensing biomedical imaging drug delivery photovoltaics new forms of optical imaging and nanoscale lasing cancer therapeutics programmable soft lithography solvent-assisted nanoscale embossing nu 2010-046 inventors mark huntington min hyung lee teri odom wei zhou abstract molding at the nanoscale has driven the production of high-density optical and magnetic storage media organic light-emitting diodes polymer photovoltaic cells and field-effect transistors while rigid molds may be used to imprint soft and semi-hard materials for these applications they are quite expensive to fabricate and brittle at nanoscale dimensions additionally current molding methods require the use of a different master for each pattern that is desired leading to significantly higher costs and increased down-time to address this researchers at northwestern university have developed an all-moldable bench-top soft nanofabrication platform that can generate nanoscale masters with programmable densities and fill factors from a single master pattern feature size feature spacing and pattern symmetry can be controlled independently this new method solvent-assisted nanoscale embossing sane combines the strengths of serial fabrication techniques with those of parallel ones in turn enabling unprecedented opportunities to manipulate the properties of nanoscale materials applications nanoscale device fabrication and design efficient creation of new molds for nanoscale patterning advantages cost effective scalable to large­area applications exceptional density and feature size control nanometer scale control over feature density publication m.h lee m.d huntington w zhou j c yang t.w odom 2011 programmable soft lithography solventassisted nanoscale embossing nano letters 11 311 ip status a patent application has been filed 14

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novel techniques for the production of large-area subwavelength hole arrays nu 2005-039 inventors joel henzie eun-soo kwak min hyung lee teri odom abstract northwestern researchers have developed a novel high throughput method for fabricating free-standing nanohole array films with precise dimensions and spacing nanohole arrays are generally produced by focused ion beam fib milling a serial low throughput process while free-standing suspended films may be fabricated by fib and reactive ion etching the generation of multi-layered films has been limited to a few metals this new invention employs a combination of phase-shifting photolithography wet-chemical etching and electron-beam deposition to generate single or multiple material films of desired thickness the high optical quality of the films were revealed by enhanced optical transmission eot in the far-field regime and surface plasmon standing wave patterns in the near-field regime the process also enables construction of anisotropic 2d nanohole arrays of varying size shape configuration curvature and pitch this technology produces optical quality hole arrays in a parallel fashion from multiple materials and in areas up to tens of square centimeters the tailorable combination of film materials shapes and polarized light result in a wide range of spectroscopic outputs with nanophotonic and sensing applications the researchers have further developed a way to produce three-dimensional nanohole arrays by starting with the first two steps in the process photolithography and etching and then depositing the metal at an angle above is deposited normal to the surface the gold film with 3d holes is then removed from the etching silicon template using an optically cured polymer this technology provides a flexible strategy to create subwavelength films whose properties are tunable for applications in chemical and biological sensing magneto-optic data storage and solar cells applications microscopy sensors magneto-optic data storage solar cells advantages simple high throughput ability to generate large area films ability to multi-layer with exceptional dimensional and thickness control publication j c yang h gao j.y suh w zhou m.h lee t.w odom nano lett 10 3173 2010 enhanced optical transmission mediated by localized plasmons in anisotropic 3d nanohole arrays ip status us issued patent no 7,999,353 15

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