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Full-Text Articles in Nanoscience and Nanotechnology

Influence Of Flow Rate, Nozzle Speed, Pitch And The Number Of Passes On The Thickness Of S1805 Photoresist In Suss Microtec As8 Spray Coater, Rohan Sanghvi, Gyuseok Kim Oct 2019

Influence Of Flow Rate, Nozzle Speed, Pitch And The Number Of Passes On The Thickness Of S1805 Photoresist In Suss Microtec As8 Spray Coater, Rohan Sanghvi, Gyuseok Kim

Tool Data

S1805 positive photoresist has been deposited on single crystalline Si wafers using a Suss MicroTec Alta Spray. The influence of flow rate, nozzle speed, pitch and number of passes on the thickness of the photoresist was studied. Results show that the thickness of S1805 is linearly proportional to the flow rate and number of passes, and inversely proportional to the nozzle speed and pitch.


Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto Mar 2019

Progress Report I: Fabrication Of Nanopores In Silicon Nitride Membranes Using Self-Assembly Of Ps-B-Pmma, Unnati Joshi, Vishal Venkatesh, Hiromichi Yamamoto

Protocols and Reports

This progress report describes fabrication of silicon nitride membranes from Si wafers using cleanroom techniques, and of nanopore preparation via a self-assembled PS-b-PMMA film. A 36.9 µm thick membrane is successfully prepared by KOH wet etching. The membrane is a layered structure of 36.8 µm thick Si and 116 nm thick silicon nitride. It is also exhibited that in the 47 nm thick PS-b-PMMA film, the nanopore structure is observed in the vicinity of a dust particle, but most of the area indicates lamellar domain structure. The thickness of PS-b-PMMA film will ...


Characterization And Optimization Of Parylene-C Deposition Process Using Scs Parylene Coater, Hannah Hastings, Eric D. Johnston, Gyuseok Kim Jan 2019

Characterization And Optimization Of Parylene-C Deposition Process Using Scs Parylene Coater, Hannah Hastings, Eric D. Johnston, Gyuseok Kim

Tool Data

Parylene-C has been deposited on bare Si wafers by physical vapor deposition using the SCS Coating Systems. Results show a 12 µm thick Parylene-C film with 10 g of dimer and negligible thickness variation across a wafer. We find a positive linear relationship between film thickness and mass of dimer at a range of 1 g to 18 g. However, the Al boat for dimer was burnt with 18 g of dimer, suggesting multiple depositions with 1 g to 10 g of dimer are recommended to achieve the Parylene-C film thicker than 12 µm.


Engineering Novel Nanomaterials From Ultrasmall Gold Clusters For Use In Cancer Therapy, Elizabeth Marie Higbee Dempsey Jan 2019

Engineering Novel Nanomaterials From Ultrasmall Gold Clusters For Use In Cancer Therapy, Elizabeth Marie Higbee Dempsey

Publicly Accessible Penn Dissertations

One of the biggest hurdles in clinical therapy is ensuring that drugs have appropriate pharmacokinetic profiles; they must traffic to sites of interest and accumulate there at relevant concentrations, but must also be eliminated from tissues at a desirable rate. This is especially important in oncology because precise tumor locations may be unknown and therapeutics are often toxic to off-target healthy tissues. Nanoscale drug formulations provide a useful way to modulate and improve the behavior of drugs within biological systems. For example, gold nanoparticles (AuNPs) can be designed with physiochemical properties that allow them to traffic from the bloodstream into ...


The Role Of Mentalizing In Information Propagation, Elisa C. Baek Jan 2019

The Role Of Mentalizing In Information Propagation, Elisa C. Baek

Publicly Accessible Penn Dissertations

What are the psychological drivers that lead to successful information propagation between communicators and receivers of shared messages? What factors lead communicators to share information with others, and receivers to be successfully influenced by the information? The current dissertation focuses on the role of mentalizing, or considering other people’s mental states, as one factor that leads to successful information propagation between communicators and receivers. Study 1 of this dissertation focused on the role of mentalizing in communicators of influence and provided behavioral evidence suggesting that mentalizing causally increases communicators’ likelihood to share information. Specifically, instructing information sharers to consider ...


Designing Colloidal Nanomaterials For Electronic And Optoelectronic Devices Through Surface Modification, Tianshuo Zhao Jan 2019

Designing Colloidal Nanomaterials For Electronic And Optoelectronic Devices Through Surface Modification, Tianshuo Zhao

Publicly Accessible Penn Dissertations

Colloidal quantum dots (QDs) are nanometer-sized semiconductors synthesized by wet chemical methods and stabilized by surface ligands in solvents. They are prized for the size-dependent electronic band structures, giving rise to tunable optical properties. Their solution form is also suitable for large-area and low-cost fabrication processes. These unique characteristics make this class of materials promising as building blocks for next-generation thin-film electronic and optoelectronic devices. However, the construction of QD based devices requires precise control of their material properties, including carrier mobility, lifetime, doping concentration and energy positions of the conduction and valence band edges. The large surface-to-volume ratio allows ...


Alignment And Morphological Effects Of Nanoplates In Lamellar Diblock Copolymer Thin Films, Nadia Krook Jan 2019

Alignment And Morphological Effects Of Nanoplates In Lamellar Diblock Copolymer Thin Films, Nadia Krook

Publicly Accessible Penn Dissertations

The ability to disperse inorganic nanoparticles (NPs) of various shapes, sizes, and compositions in polymeric matrices enables researchers to continuously engineer new material combinations with different resulting properties. Polymer nanocomposites (PNCs) can be further customized for specific applications by intentionally organizing and orienting NPs within these hybrid materials. Despite significant advances in the field of PNCs, full control over the orientation of embedded anisotropic NPs, specifically nanoplates, is not well-established without employing multistep processes. Capturing either in-plane (parallel) or out-of-plane (vertical) orientation of nanoplates in thin polymer films through a scalable method would create new opportunities for developing coating technologies ...


Alternating Multiblock Polyethylenes With Associating Groups: Self-Assembled Nanoscale Morphologies And Ion Transport, Lu Yan Jan 2019

Alternating Multiblock Polyethylenes With Associating Groups: Self-Assembled Nanoscale Morphologies And Ion Transport, Lu Yan

Publicly Accessible Penn Dissertations

Single-ion conductors based on block copolymers (BCPs) are promising solid-state electrolytes for energy storage systems. Their ability to self-assemble into distinct nanostructures can provide both high ion transference numbers and strong mechanical integrity. Connecting the microphase-separated morphologies to the ion transport properties in BCP electrolytes as well as designing polymers to produce specific ion-conducting domain remain a critically important challenge.

Combining non-conducting polyethylene (PE) blocks that alternate with short strongly-interacting ionic blocks leads to a wide range of intriguing nanoscale phase-separated morphologies. Depending on the PE block lengths, these alternating multiblock copolymers exhibit amorphous or semicrystalline morphologies and their ionic ...


Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda Jan 2018

Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda

Publicly Accessible Penn Dissertations

Nanopore-based devices provide the ability to detect, analyze and manipulate molecules by monitoring changes in ionic current and sieving molecules dissolved in an electrolyte. While devices with single nanopores can be used as molecular sensors and analyzers, including as a possible high-throughput DNA sequencer, devices with multiple nanopores (nanoporous devices) can be used to filter out ions from solutions, with possible use in water desalination. Sensitivity and molecular flux can be enhanced by using two-dimensional (2D) materials, like graphene and transition metal dichalcogenides (TMDs), as the nanopore membrane. However, these devices face challenges yet to be solved, including (a) fast ...


Characterizing The Energetic Landscape In Solution Processable Solar Cells Via Frequency-Dependent Impedance Measurements, Eric S. Wong Jan 2018

Characterizing The Energetic Landscape In Solution Processable Solar Cells Via Frequency-Dependent Impedance Measurements, Eric S. Wong

Publicly Accessible Penn Dissertations

This thesis presents measurements and analyses aimed at describing charge transport dynamics in quantum dot (QD) photovoltaics (PVs). Due to their solution processability and unique size-dependent optoelectronic properties, ensembles of electronically coupled QDs (QD solids) provide an exciting platform for next generation PV devices. However, the structural disorder associated with the formation of conductive QD solids gives rise to a complicated density of states (DOS) emerging from the distribution of mesoscale charge dynamics occurring in these materials.

I present phenomological models to describe the DOS in the disordered energetic and spatial landscape of QD solids that relies on a suite ...


Microlamination Based Lumped And Distributed Magnetic Mems Systems Enabled By Through-Mold Sequential Multilayer Electrodeposition Technology, Yuan Li Jan 2018

Microlamination Based Lumped And Distributed Magnetic Mems Systems Enabled By Through-Mold Sequential Multilayer Electrodeposition Technology, Yuan Li

Publicly Accessible Penn Dissertations

Microfabricated magnetic MEMS components such as permanent micromagnets and soft magnetic structures are key enablers in various lumped and distributed systems such as energy harvesters, magnetometers, biomagnetic filters, and electromagnetic micromotors. The unique functionalities of such systems often require designers to controllably scale the relevant dimensions of a device relative to the characteristic length of a targeted application. We demonstrate in this dissertation that the developed Microlamination Technology could create two-dimensional uniform- or dual- height monolithic metallic structures with additional deterministic structural and compositional complexities along thickness direction, suitable to facilely and flexibly fabricate both lumped and distributed magnetic MEMS ...


Characterization Of Sputtering Copper Using The Denton Explorer-14 System, Roman Mays, Meredith Metzler Mar 2017

Characterization Of Sputtering Copper Using The Denton Explorer-14 System, Roman Mays, Meredith Metzler

Tool Data

No abstract provided.


Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Silicon Nitride (Sinx) Using Oxford Instruments System 100 Pecvd, Meredith Metzler, Raj Patel Feb 2017

Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Silicon Nitride (Sinx) Using Oxford Instruments System 100 Pecvd, Meredith Metzler, Raj Patel

Tool Data

This report discusses the deposition process of SiNx using the Oxford System 100 PECVD.


Optimization Of Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Amorphous Silicon (A-Si) Using Oxford Instruments System 100 With Taguchi L9 Based Design Of Experiments (Doe), Raj Patel, Meredith Metzler Feb 2017

Optimization Of Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Amorphous Silicon (A-Si) Using Oxford Instruments System 100 With Taguchi L9 Based Design Of Experiments (Doe), Raj Patel, Meredith Metzler

Tool Data

No abstract provided.


Examination Of The Stoney Equation And A Practical Determination Of The Error In Residual Film Stress Measurements, Roman Mays Feb 2017

Examination Of The Stoney Equation And A Practical Determination Of The Error In Residual Film Stress Measurements, Roman Mays

Protocols and Reports

No abstract provided.


Characterization Of Sputtering Platinum Using The Denton Explorer-14 System, Roman Mays Feb 2017

Characterization Of Sputtering Platinum Using The Denton Explorer-14 System, Roman Mays

Tool Data

No abstract provided.


Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Silicon Dioxide (Sio2) Using Oxford Instruments System 100 Pecvd, Meredith Metzler, Raj Patel Feb 2017

Plasma Enhanced Chemical Vapor Deposition (Pecvd) Of Silicon Dioxide (Sio2) Using Oxford Instruments System 100 Pecvd, Meredith Metzler, Raj Patel

Tool Data

This report discusses the deposition process of SiO2 using the Oxford System 100 PECVD.


The Measurement Of Residual Film Stress In Deposited Thin Films Using The Kla-Tencor 2d/3d P7 Surface Profilometer, Roman Mays Feb 2017

The Measurement Of Residual Film Stress In Deposited Thin Films Using The Kla-Tencor 2d/3d P7 Surface Profilometer, Roman Mays

Protocols and Reports

No abstract provided.


Inkjet Printing Of Ag Nanoparticles Using Dimatix Inkjet Printer, No 1, Amal Abbas, Inayat Bajwa Jan 2017

Inkjet Printing Of Ag Nanoparticles Using Dimatix Inkjet Printer, No 1, Amal Abbas, Inayat Bajwa

Protocols and Reports

Ag nanoparticle inkjet printing on polyimide and polyethylene terephthalate films has been performed using Dimatix inkjet printer at Quattrone Nanofabrication Facility. This article describes selection of Ag nanoparticle inks and reports the progress of optimization of drop spacing, drop frequency, droplet size, and waveform for high resolution features, and furthermore reveals the pros and cons of Dimatix inkjet printing. In addition, the resistivity of Ag nanoparticle line sintered was determined to be ~2.2 x 10-5 Ωm. The adhesion and bending tests indicated that Ag nanoparticle pattern sintered on PI and PET films had exceptional mechanical stability.


Understanding Dewetting Transitions On Nanotextured Surfaces: Implications For Designing Surfaces With Improved Wettability, Suruchi Fialoke Jan 2017

Understanding Dewetting Transitions On Nanotextured Surfaces: Implications For Designing Surfaces With Improved Wettability, Suruchi Fialoke

Publicly Accessible Penn Dissertations

Despite the early promise of superhydrophobic surfaces, their widespread technological adoption has been dawdled by the ease with which water can penetrate the surface texture, resulting in a breakdown of superhydrophobicity. Furthermore, this breakdown is believed to be irreversible, because large adhesion barriers impede the dewetting of the surface texture and the concomitant recovery of superhydrophobicity. Using molecular dynamics simulations in conjunction with advanced sampling techniques, in this thesis, we challenge this conventional argument. We show that while large barriers do typically impede the recovery of superhydrophobicity, it can nevertheless be recovered spontaneously on nanotextured surfaces, wherein collective water density ...


Filomicelles Deliver A Chemo-Differentiative Therapy To Durably Control Carcinoma Cell Fate, Praful Raveendran Nair Jan 2017

Filomicelles Deliver A Chemo-Differentiative Therapy To Durably Control Carcinoma Cell Fate, Praful Raveendran Nair

Publicly Accessible Penn Dissertations

Current chemotherapy causes a host of side effects and better delivery of drugs to tumors is required to reduce this. Nanocarriers have been proven to not only deliver better to tumors but also solubilize more drugs in the core, with flexible ‘filomicelles’ being particularly effective. They are still open to improvements and one obvious way is to increase drug loading and hence drug dosage delivered to tumors. In the first part, the core of filomicelles was modified by the integration of aromatic groups into the hydrophobic block of a degradable di-block copolymer with the aim of improving delivery of aromatic ...


Nano/Biosensors Based On Large-Area Graphene, Pedro Jose Ducos Jan 2017

Nano/Biosensors Based On Large-Area Graphene, Pedro Jose Ducos

Publicly Accessible Penn Dissertations

Two dimensional materials have properties that make them ideal for applications in chemical and biomolecular sensing. Their high surface/volume ratio implies that all atoms are exposed to the environment, in contrast to three dimensional materials with most atoms shielded from interactions inside the bulk. Graphene additionally has an extremely high carrier mobility, even at ambient temperature and pressure, which makes it ideal as a transduction device. The work presented in this thesis describes large-scale fabrication of Graphene Field Effect Transistors (GFETs), their physical and chemical characterization, and their application as biomolecular sensors. Initially, work was focused on developing an ...


Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner Jan 2017

Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner

Publicly Accessible Penn Dissertations

As semiconductor manufacturing pushes towards smaller and faster transistors, a parallel goal exists to create transistors which are not nearly as small. These transistors are not intended to match the performance of traditional crystalline semiconductors; they are designed to be significantly lower in cost and manufactured using methods that can make them physically flexible for applications where form is more important than speed. One of the developing technologies for this application is semiconductor nanocrystals.

We first explore methods to develop CdSe nanocrystal semiconducting “inks” into large-scale, high-speed integrated circuits. We demonstrate photopatterned transistors with mobilities of 10 cm2/Vs on ...


Engineering Plasmonic Nanocrystal Coupling Through Template-Assisted Self-Assembly, Nicholas J. Greybush Jan 2017

Engineering Plasmonic Nanocrystal Coupling Through Template-Assisted Self-Assembly, Nicholas J. Greybush

Publicly Accessible Penn Dissertations

The construction of materials from nanocrystal building blocks represents a powerful new paradigm for materials design. Just as nature’s materials orchestrate intricate combinations of atoms from the library of the periodic table, nanocrystal “metamaterials” integrate individual nanocrystals into larger architectures with emergent collective properties. The individual nanocrystal “meta-atoms” that make up these materials are themselves each a nanoscale atomic system with tailorable size, shape, and elemental composition, enabling the creation of hierarchical materials with predesigned structure at multiple length scales. However, an improved fundamental understanding of the interactions among individual nanocrystals is needed in order to translate this structural ...


Adhesion And Wear Of Nanoscale Polymer Contacts, Yijie Jiang Jan 2017

Adhesion And Wear Of Nanoscale Polymer Contacts, Yijie Jiang

Publicly Accessible Penn Dissertations

Atomic force microscopy (AFM) is a powerful tool for high resolution surface measurements, nanolithography, and tip-based nanomanufacturing. An understanding of the nanoscale tribological behavior of the tip-sample contact, including adhesion and wear, is critical in these applications. In this dissertation, the adhesion and wear of polymethyl methacrylate (PMMA) in contact with an ultrananocrystalline diamond (UNCD) AFM tip is investigated using a combination of AFM-based nanomechanics experiments and finite element analysis (FEA).

A novel AFM-based method, which combines pull-off force measurements and characterization of the 3D geometry of AFM tip, was developed to quantify the properties of the adhesive traction-separation relationship ...


Optical Modeling And Analysis Of Disordered Plasmonic Nanoparticle Ensembles, Chen Li Jan 2017

Optical Modeling And Analysis Of Disordered Plasmonic Nanoparticle Ensembles, Chen Li

Publicly Accessible Penn Dissertations

Plasmonic nanoparticle synthesis provids a facile and cost-effective bottom-up solution to fabrication of nanoscaled structures. With effective packaging methods like embedding into polymer composites and superlattice assemblies, the chemically synthesized nanoparticles are promising candidates for functional devices. However, compared with precisely patterned surfaces commonly used for device fabrication, the structural inhomogenity and disorder in nanoparticle ensembles give rise to challenge in their characterization using conventional methods and in turn, their application. This work aims to develop models as guideline to design facile characterization methods that can be used to effectively describe the properties of disordered plasmonic nanoparticle ensembles. Two types ...


Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour Jan 2017

Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour

Publicly Accessible Penn Dissertations

Cell tracking offers the opportunity to study migration and localization of cells in vivo, allowing investigations of disease mechanisms and drug efficacy. Monocytes play a key role in the progression of atherosclerotic plaques in the coronary arteries. While x-ray computed tomography (CT) is commonly used to clinically assess coronary plaque burden, cell tracking with CT is mostly unexplored. The establishment of monocyte cell tracking tools would allow for the direct investigation of gene and drug therapies aimed at monocyte recruitment in atherosclerosis. In this thesis, we present the design and optimization of gold nanoparticles as CT contrast agents for cell ...


Beyond Graphene: Monolayer Transition Metal Dichalcogenides, A New Platform For Science, Carl Hugo Naylor Jan 2017

Beyond Graphene: Monolayer Transition Metal Dichalcogenides, A New Platform For Science, Carl Hugo Naylor

Publicly Accessible Penn Dissertations

Following the isolation of graphene in 2004, scientists quickly showed that it possesses remarkable properties. However, as the scientific understanding of graphene matured, it became clear that it also has limitations: for example, graphene does not have a bandgap, making it poorly suited for use in digital logic. This motivated explorations of monolayer materials “beyond graphene”, which could embody functionalities that graphene lacks. Transition metal dichalcogenides (TMDs) are leading candidates in this field. TMDs possess a wide variety of properties accessible through the choice of chalcogen atom, metal atom and atomic configuration (1H, 1T, and 1T’). Similar to graphene, monolayer ...


Designing Plasmonic Materials And Optical Metasurfaces For Light Manipulation And Optical Sensing, Wenxiang Chen Jan 2017

Designing Plasmonic Materials And Optical Metasurfaces For Light Manipulation And Optical Sensing, Wenxiang Chen

Publicly Accessible Penn Dissertations

Metamaterials are artificial materials designed to create optical properties that do not exist in nature. They are assemblies of subwavelength structures that are tailored in size, shape, composition, and orientation to realize the desired property. Metamaterials are promising for applications in diverse areas: optical filters, lenses, holography, sensors, photodetectors, photovoltaics, photocatalysts, medical devices, and many more, because of their excellent abilities in bending, absorbing, enhancing and blocking light. However, the practical use of metamaterials is challenged by the lack of plasmonic materials with proper permittivity for different applications and the slow and expensive fabrication methods available to pattern sub-wavelength structures ...


Elionix Els-7500ex: Field Size Analysis, Gerald G. Lopez Ph.D., Mohsen Azadi Dec 2016

Elionix Els-7500ex: Field Size Analysis, Gerald G. Lopez Ph.D., Mohsen Azadi

Protocols and Reports

This report documents the field distortion of the Elionix ELS-7500EX electron beam lithography system at the University of Pennsylvania Singh Center for Nanotechnology at the Quattrone Nanofabrication Facility. The system is equipped with a 20MHz fixed clock and fixed focus. The aim of the work is to understand optimal field sizes to use for critical dimensions 80nm and above. Field uniformity was analyzed as a function of critical dimension and objective lens aperture (OLA) a.k.a. final paerture. As features scale down below 300nm, they are more susceptible to the systematic effects of field distortion. Suggested field sizes depend ...