During my summer internship at CNSE, I have been working mainly with the Filmetrics F20 thin film analyzer. Filmetrics is useful in quickly determining the thickness of contamination on samples of silicon or ruthenium. I have been taking measurements on contaminated silicon mirrors to determine the thickness of carbon contamination. In trying to understand how Filmetrics works better I have also been doing calculations for thin film problems (calculating the reflection at different wavelengths and predicting variations in reflection for different wavelengths). The second part of my internship has been to determine if the stage with which samples are placed on is effecting measurements.
Casey Strader, CNSE Intern
July 30, 2009
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My mentor and I have derived a diffusion equation to predict concentrations of diffusing Epidermal Growth Factor as a function of time and radius from the source. I am currently conducting various experiments to determine the number of EGF particles that are released from micro-scale devices as a function of time so that I can incorporate a term to the diffusion equation to cater it to our situation. This enhanced diffusion equation will allow us to predict precise concentrations of EGF outside of our device based on curve fits from experimental results. As a supplement to the mathematics-based diffusion model I am also developing a computer program that simulates the diffusion of the EGF molecules in a bounded space. This simulation is based on simple Brownian Motion of a large number of individual particles and takes into account the diffusivity of the suspended particles, temperature and particle-boundary collisions. Our hope is to be able to determine the initial concentrations of EGF that optimize the chemoattractant character of the device.
Douglas Eggers, CNSE Intern
July 29, 2009
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During my internship, I am working to model the shrinkage phenomenon. To do this, it is very important to know how much energy is deposited in the photoresist. So, my team has simulated it with a program which is a good approximation of the real phenomenon. We have also used the finite element method, meaning that we have considered our material (the photoresist) like a cell array. This way, we are seeing how they are changing in each electron beam scan.
Right now, we are simulating in two dimensions, the photoresist and working with matrixes in the plane. Then, we have to compare our result from the simulation with the real data. This part is very important because we can tell if our model is correct or not. The model can also be improved by adding or changing some more variables.
Daniel Aguilar, CNSE Intern
July 28, 2009
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This is my second blog post of the summer and the eighth week of my internship. I have started working with new software called lab-view which is used for data acquisition, instrument control, and industrial automation on a variety of operating systems. I am still reading a plethora of research papers but I think I've honed my skills to extract critical data from papers. I have also learned how to correlate information between papers. Throughout the papers I've learned about different ways to evaluate the tribiological properties of thin films, such as different techniques for analyzing viscoelastic materials whether it is by Nanoidentation, Atomic Force Acoustic Microscopy (AFAM), Ultra Sonic Microscopy (UFM) , or Contact-Resonance AFM (CRAVE). Modeling, not the type you see on the catwalk, but rather the Kelvin-Voight model, Hertzian- contact model , Derjaguin- Muller Toporov (DMT) are all fully evident in the papers and they all hope to be the best at modeling the viscoelastic properties of materials. Also you can't forget about AFM Tip-Sample contact mechanics which also have various ways of being represented.
Besides modeling I've also learned another important skill that comes with research, being able to network with other research scientists. For example, today I learned how to use the AFM and how the mechanical components work with the software components. This Thursday we are having a teleconference with a great research scientist from National Institute of Standards and Technology (NIST), a CNSE partner, who has done something very similar to what we are trying to do. This is the amazing thing about research - if the scientists are able to share their methods for success they will help one another to improve the technology for the future.
Carl Irani, CNSE Intern
July 23, 2009
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The focus of my internship has been mainly on the impact of topographical cues on the number of glial cells vs. the number of neurons (using quantitative data to compare).
Once the CNSC have differentiated to either glial cells or neurons on the topographically modified surfaces that I made, images were taken and the different types of cells were counted, while taking into account the gap and width size of the columns on which the cells were located.
Statistical calculations were taken on the data obtained, yet the influence of columns on cell type (differentiation) remains to be found.
This is quite curious considering that past research has concluded that topographies influence neural growth and orientation, while similarly persuading astroglial cells to have different geometries.
In weeks to come more arrays will have stem cells cultured on them, the cells will differentiate, they will be stained, mounted, and counted. Once the second batch of topographies (with cells on them) have been stained and mounted I will begin to focus on if the surfaces influence whether the stem cells differentiate into either oligodendrocytes or astrocytes (glial cells).
Alicia McCarthy, CNSE Intern
July 22, 2009
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Direct cell printing with microfabricated polymeric "quill-pen" cantilevers is useful for controlling and manipulating the position of cells on solid surfaces. When compared to other cell deposition methods, such as laser ablation, the quill-pen approach minimizes thermal stress and shear force on cells, therefore preserving cell viability and biological functionality. The size of the printed spots depends on the geometry of the quill-pen stylus, contact time between the cantilever and the surface, humidity of the Nano eNabler chamber, print tool angle, and surface hydrophobicity. The goal of my project is to evaluate the quill-pen cell deposition technique for its compatibility with multiple cell types and cell viability.
In the first few weeks of my internship at CNSE, I tested different quill-pen stylus geometries with 10 μm diameter polymer beads in solution for variation in spot size and the number of beads per droplet. Recently, I have tested the viability of printed bacterial and mammalian cells using live/dead staining. I will continue exploring various substrates and sterilization processes. Further research is needed to optimize the proliferation duration and minimize the differentiation of the printed cells.
Katherine Lee, CNSE Intern
July 21, 2009
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Lithography is a word with two distinct definitions. If you Google "lithography", 7 of the first 10 hits will refer you to the art world and a process invented by Aloys Senefelder in 1788(1). A short description of the process from the Merriam-Webster Online Dictionary defines it as "the process of printing from a plane surface (as a smooth stone or metal plate) on which the image to be printed is ink-receptive and the blank area ink-repellent". This definition belies the major role that the second definition plays in modern society. Again, from Merrian-Webster, we have the second definition: "the process of producing patterns on semiconductor crystals for use as integrated circuits". It is not an understatement to claim that progress in lithography is the engine that has driven much of the world's high-tech economy over the last 50 years. Read the whole article
John Hartley, CNSE Professor of Nanoengineering
July 20, 2009
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With thinner crowds at SEMICON West than in previous years, vendors are still optimistic at the opportunities ahead and the continuing growth within the industry.
As SEMICON officially comes to a close, it was another successful show for CNSE with speakers and announcements, proving that New York State is at the center of the nanotechnology industry.
CNSE staff
July 16, 2009
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There was a lot of talk this morning about the great networking at CNSE partner SEMATECH's jam-packed reception last night. The networking continued into the final day of the conference as was evident by the well-attended TEL booth.
CNSE staff
July 16, 2009
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CNSE's second presenter at SEMICON West, Rich Brilla, discussed Extending Moore's Law this afternoon at the TechXPOT. Brilla's presentation was a hit with lots of interest and questions.
CNSE staff
July 15, 2009
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This morning a major new nanotechnology venture was announced for Upstate New York. Assembly Speaker Sheldon Silver, joined by Gov. David A. Paterson and Assemblywoman RoAnn M. Destito, announced the creation of a high-tech venture between SUNY Institute of Technology SUNYIT and CNSE, establishing the Computer Chip Hybrid Integration Partnership (CHIP).
There was a lot of buzz surrounding this announcement at SEMICON West today.
CNSE staff
July 15, 2009
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After a great preview article featuring CNSE in the SEMICON Show Daily, there was a large turn-out for CNSE's first speaker, Dr. Bob Geer.
Geer described how the transition to multi-core on-chip architectures has rapidly changed the landscape for end-of-roadmap interconnect paradigms, highlighting the need to leverage 3D processing, novel signaling approaches, new material introduction and post-CMOS switch integration to maintain equivalent scaling well beyond 22nm.
The crowd displayed a lot of interest in the presentation and had several questions for Dr. Geer.
CNSE staff
July 14, 2009
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We have a busy day at SEMICON West today. There is a lot of buzz around the show's TechXPOT, featuring industry experts, CNSE's Bob Geer among them, presenting at 12:10. Dr. Geer's presentation will focus on Evolution of On-Chip Interconnects.
CNSE staff
July 14, 2009
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CNSE academic and technical experts are in San Francisco for SEMICON West 2009, the industry's major conference. As the show gets started, CNSE hits the ground running, announcing a $20M partnership with Novellus Systems.
The show begins tomorrow, where CNSE Vice President for Academic Affairs and CNSE Chief Academic Officer Dr. Robert Geer will present at SEMICON West's TechXPOT on nanoelectronics advances. Wednesday's TechXPOT will feature CNSE Vice President for Strategy, Alliances and Consortia Richard Brilla.
Follow us on Twitter for updates throughout the week.
CNSE staff
July 13, 2009
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Radiation therapy and auto-immune diseases can functionally disable an otherwise healthy salivary gland, compromising an affected person's ability to produce saliva and therefore to mediate the growth of oral microorganisms, to chew and swallow, and to maintain healthy teeth. Together with UAlbany's Life Sciences department, my team of researchers is electrospinning nanofibers into biodegradable scaffolds for in vitro salivary gland production. Our group hopes to prove that nanofibers provide an advantageous environment for cell proliferation as compared to flat polymer surfaces.
Electrospinning is the practice of electrically extracting tiny, dry fibers from a dissolved state. In our setup, a capacitor (an electrified needle-tip lifted ten or fifteen centimeters above a ground plate) charges hexafluoroisopropanol-polymer solution. A sub-micron jet of dissolved fiber then sprouts from the surface of the solution that protrudes from the needle tip and accelerates toward the ground plate. This hopefully stretches the interlinking chains of polymer into even thinner fibers. Mid-flight, however, the submicron jet is always subject to perturbation from outside forces (a stream of air or the vibrations in the floor, for example) and the fibers are strewn so that they cover the entire three- or four-square-inch collecting plate.
Because our collaborators require both sub-micron and micron-sized fibers for their experiments, we have been working to "tweak" parameters of our setup to favor the production (and eventually the reproduction) of fibers of many different diameters. Among our objectives for the summer are to reproduce control of fiber diameter; to continue to prevent "beading," or irregular lumping, in our samples; and to optimize anchor-ability of the fibers to cover slips. So far, the group has a lot of "interesting preliminary data" from earlier experiments, the validity of which my mentor and I are working hard to reinforce. We are doing so by designing experiments that both produce the must-needed fibers for testing, and that strengthen our understanding of the complex electrospinning system.
Mike Melfi, CNSE Intern
July 9, 2009
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Electron beam lithography is used to pattern devices down to a few nanometers. The electron beam lithography tool has a few advantages over conventional lithography in that the diffraction limit of light can be overcome due to the shorter wavelength of the 10-50keV energy electrons impinging on the resist film. Another advantage of the electron beam lithography tool is that it requires no physical mask (although conventional UV photolithography masks are written using the electron beam lithography tool). The mask used in the writing of the pattern is stored as a software mask.
My project involves the patterning of substrates to be used for investigations into biological phenomena. Currently I have designed various patterns using MEMS (Micro-Electro-Mechanical systems) CAD (Computer Aided Design) software to be implemented into the electron beam lithography tool as a software mask. Some devices I have designed include a microfluidic deformation chamber for studying cancer metastasis and the degradation of extracellular matrix proteins; an extracellular matrix protein topography imitation for studying cell motility and adhesion; a microfluidic cell-cell junction assay; and an array of various passive micro and nanofluidic valve channels. Over the course of the next few weeks these designs will be patterned into a substrate using the VB300 electron beam tool in CNSE's NanoFab North cleanroom and used for PDMS (Polydimethylsiloxane) replica molding.
During the course of my time here at CNSE I have been collaborating with individuals from an assortment of academic and industrial backgrounds, all of which have provided me with an excellent opportunity for continued and superior learning experiences.
William Stephenson, CNSE Intern
July 8, 2009
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It has been almost 5 weeks since I started as an intern at CNSE. After receiving my acceptance email, I got another one saying: Steve, the project you will be working on is Vacuum ultraviolet spectrometry and calibrations. At the time, it made no sense to me. Even Google could not give me any help about that specific topic. Before actually getting into what this project is, I want to first discuss this amazing experience.
CNSE is very unique. The facility is big (I still get lost when I am trying to go from one wing to another) and so many great scientists are working on-site. The best experience I had so far was my first time in the cleanroom. I was so excited when Leo told us to follow him to the cleanroom. We had to wear glasses, gloves, and a bunny suit - every single part of our body had to be covered. In other words, be really clean before entering a clean room. Once inside, we were to take apart our vacuum chamber and figure out why and where it was leaking. We have a high vacuum chamber whose pressure is about .
My project consists of two parts: designing and programming. I will be improving or designing new parts when needed. This will be done using AutoCAD. For example, my first assignment was to make a new stage and a holder for our grating. We needed to add a Z motion to the grating.
I will also improve our existing MATLAB program. It was designed to determine the species that are outgassed during a EUV exposure. However, it does not give us complete satisfaction. Our mass spectrometer outputs data, which after being converted, will tell us how many particles were outgassed. Resist outgassing is a major problem in lithography. This is because we use a mirror to direct the EUV light toward the mask. However, those outgassed particles will deposit on mirrors decreasing their reflectivity. Being able to precisely determine which species are present in our chamber will save us time and money.
Steve Kana Mbazo, CNSE Intern
July 7, 2009
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Since the beginning of my internship at CNSE, I have learned many things: from simpler ideas such as the safety requirements to work in the lab, to more complex skills like preparing different kind of compounds. Being here made me realize that you need to be very careful in every action you do; everything is important and a little change can alter your product.
The project I'm working on for my internship is synthesizing acid amplifiers. These compounds are part of a photoresist. The resist is a polymer that covers the silicon wafer. The resist film can be imaged using EUV light. The goal of the project is to improve the resist resolution, LER (Line Edge Roughness), and sensitivity so that smaller computer chips can be made. The photoresist prepared with acid amplifiers works with EUV lithography. The EUV light has a wavelength of approximately 13.5nm. When it comes over the wafer, it interacts with another part of the photoresist called PAG (Photo Acid Generator), to generate an acid which interacts with the acid amplifier to generate more acid in an autocatalytic way.
My participation during my internship consists of preparing some acid amplifiers. I am also working with software to simulate the strength of the bonds in the compounds and learning a little bit about how to get NMR spectrums.
Sara Cruz, CNSE Intern
July 6, 2009
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