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Displaying 201 - 225 of 718

Atom Probe Tomography Analysis of Ag Doping in 2D Layered Material (PbSe)5(Bi2Se3)3

September 7, 2016
Author(s)
Arunima Singh, Albert Davydov, Francesca M. Tavazza, Lincoln J. Lauhon, Xiaochen Ren, Mercouri G. Kanatzidis, Lei Fang
Impurity doping in two-dimensional (2D) materials can provide a route to tuning electronic properties, so it is important to be able to determine the distribution of dopant atoms within and between layers. Here we report the tomographic mapping of dopants

Roles of Nanofiber Scaffold Structure and Chemistry in Directing Human Bone Marrow Stromal Cell Response

August 22, 2016
Author(s)
Sumona Sarkar, Bryan A. Baker, Desu Chen, Patrick S. Pine, Jennifer H. McDaniel, Marc L. Salit, Wolfgang Losert, Carl G. Simon Jr., Joy P. Dunkers
Nanofiber technology has emerged as a promising tool to recapitulate the native extracellular matrix structure; however the properties of nanofibers governing cell-material interactions are still largely undetermined. In this study we have systematically

Charge Carrier Dynamics and Mobility Determined by Time-Resolved Terahertz Spectroscopy on Films of Nano-to-Micrometer-Sized Colloidal Tin(II) Monosulfide

August 1, 2016
Author(s)
Brian Alberding, Adam Biacchi, Angela R. Hight Walker, Edwin J. Heilweil
Tin(II) monosulfide (SnS) is a semiconductor material with an intermediate band gap, high absorption coefficient is the visible range, and consists of earth abundant, non-toxic elements. For these reasons, SnS has generated much interest for incorporation

Coherent and incoherent coupling dynamics between neutral and charged excitons in Monolayer MoSe2

July 18, 2016
Author(s)
Kai Hao, Lixiang Xu, Philip Nagler, Akshay Singh, Kha Tran, Chandriker K. Dass, Rupert Huber, Tobias Korn, Xiaoqin Li, Galan Moody
The optical properties of semiconducting transition metal dichalcogenides are dominated by both neutral excitons (electron-hole pairs) and charged excitons (trions) that are stable even at room temperature. While trions directly influence charge transport

Modeling early breakdown failures of gate oxide in SiC power MOSFETs

July 14, 2016
Author(s)
Zakariae Chbili, Asahiko Matsuda, Jaafar Chbili, Jason T. Ryan, Jason P. Campbell, Mhamed Lahbabi, D. E. Ioannou, Kin P. Cheung
One of the most serious technology roadblocks for SiC DMOSFETs is the significant occurrence of early failures in time-dependent-dielectric-breakdown (TDDB) testing. Conventional screening methods have proved ineffective because the remaining population is

Advancing X-Ray Scattering Metrology Using Inverse Genetic Algorithms

July 7, 2016
Author(s)
Adam F. Hannon, Daniel F. Sunday, Donald A. Windover, Regis J. Kline
We compare the speed and effectiveness of two genetic optimization algorithms to the results of statistical sampling via a Markov Chain Monte Carlo algorithm to find which is the most robust method for determining real space structure in periodic gratings

Electron Enhanced Growth of Crystalline Gallium Nitride Thin Films at Room Temperature and 100 C Using Sequential Surface Reactions

July 1, 2016
Author(s)
Alexana Roshko, Jaclyn Sprenger, Andrew S. Cavanagh, Steven George, Huaxing Sun, Kathryn J. Wahl
Low energy electrons may provide mechanisms to enhance thin film growth at low temperatures. In this work, gallium nitride (GaN) films were deposited over areas of ~5 cm2 at room temperature and 100 C using electrons with a low energy of 50 eV from an

Transient thermometry and high-resolution analysis of filamentary resistive switches

June 28, 2016
Author(s)
Jonghan Kwon, Chao-Yang Chen, Abhishek Sharma, Andrea Fantini, Malgorzata Jurczak, James A. Bain, Yoosuf Picard, Marek Skowronski, Andrew Herzing
We present data on the filament size and temperature distribution in Hf0.82Al0.18Ox-based Resistive Random Access Memory (RRAM) devices obtained by transient thermometry and high- resolution transmission electron microscopy (HRTEM). The thermometry shows

Characterization of Buried Interfaces with Scanning Probe Microscopes

May 19, 2016
Author(s)
Joseph J. Kopanski, Lin You, Jungjoon Ahn, Yaw S. Obeng
Scanning probe microscopes (SPMs) have some capability to image sub-surface structure, including the details of buried interfaces. This paper describes the theoretical and practical basis for obtaining information about shallow buried interfaces

Low Frequency Radio Wave Detection of Electrically Active Defects in Dielectrics

May 19, 2016
Author(s)
Yaw S. Obeng, Chukwudi A. Okoro, Pavel Kabos, Rhonda R. Franklin, Papa K. Amoah
In this paper, we discuss the use of low frequency (up to 300 MHz) radio waves (RF) to detect and characterize electrical defects present in the dielectrics of emerging integrated circuit devices. As an illustration, the technique is used to monitor the

In-Situ Metrology to Characterize Water Vapor Delivery during Atomic Layer Deposition

May 2, 2016
Author(s)
Tariq Ahmido, William A. Kimes, Brent A. Sperling, Joseph T. Hodges, James E. Maslar
Water is often employed as the oxygen source in metal oxide atomic layer deposition (ALD) processes. It has been reported that variations in the amount of water delivered during metal oxide ALD can impact the oxide film properties. Hence, one contribution

A ROUND ROBIN EXPERIMENT TO SUPPORT BOND VOID MEASUREMENT STANDARDS

May 1, 2016
Author(s)
Richard A. Allen, David T. Read, Victor H. Vartanian, Winthrop A. Baylies, William Kerr, Mark Plemmons, Kevin T. Turner
A round robin experiment to compare the sensitivities of various metrology tools to small voids between bonded wafers such as are used in three-dimensional stacked integrated circuits (3DS-ICs) and MEMS packaging. Participants received a set of four bonded

Hardware Security Thorough Supply Chain Assurance

April 28, 2016
Author(s)
Yaw S. Obeng, David A. Brown, Colm Nolan
This paper examines the current issues pertaining to the hardware security and how they could affect the overall security of applications such as the internet of things. Specifically, we review the ongoing industry-led activities aimed at mitigating the

Rapid Fabrication of Poly(DL-lactide) Nanofiber Scaffolds with Tunable Degradation for Tissue Engineering Applications by Air-brushing

April 28, 2016
Author(s)
Adam M. Behrens, Jeffrey J. Kim, Nathan A. Hotaling, Jonathan Seppala, Peter Kofinas, Wojtek J. Tutak
Polymer nanofiber based materials have been widely investigated for use as tissue engineering scaffolds. While promising, these materials are typically fabricated through techniques that require significant time or cost. Here we report a cost effective

Optical Spintronics in Organic-Inorganic Perovskites Photovoltaics

April 25, 2016
Author(s)
Junwen Li, Paul M. Haney
Organic-inorganic halide CH 3NH 3PbI 3 solar cells have attracted enormous attention in recent years due to their remarkable power conversion efficiency. These materials should exhibit interesting spin-dependent properties as well, owing to the strong spin

Exciton Dynamics in Monolayer Transition Metal Michalcogenides

April 19, 2016
Author(s)
Galan A. Moody, John Schaibley, Xiaodong Xu
Since the discovery of semiconducting monolayer transition metal dichalcogenides, a variety of experimental and theoretical studies have been carried out seeking to understand the intrinsic exciton population decay and valley relaxation dynamics. Reports

Enabling Quantitative Optical Imaging for In-die-capable Critical Dimension Targets

April 4, 2016
Author(s)
Bryan M. Barnes, Mark Alexander Henn, Martin Y. Sohn, Hui Zhou, Richard M. Silver
Dimensional scaling trends will eventually bring the semiconductor critical dimensions (CDs) down to only a few atoms in width. New optical techniques are required to address intra-die variability for these CDs using sufficiently small in-die metrology

Dual-beam laser thermal processing of silicon photovoltaic materials

March 14, 2016
Author(s)
Brian J. Simonds, Anthony Teal, Tian Zhang, Joshua A. Hadler, Zibo Zhou, Sergey Varlamov, Ivan Perez-Wurfl
Laser processing for photovoltaics (PV) has traditionally been used for very small dimension features where focused beams are rastered to create lines for edge isolation, scribing, and selective emitter formation and for drilling holes for drilling in wrap

Field Effects of Current Crowding at Metal-MoS2 Contacts

March 10, 2016
Author(s)
Hui H. Yuan, Guangjun Cheng, Sheng Yu, Angela R. Hight Walker, Curt A. Richter, Qiliang Li
Gate assisted contact-end Kelvin test structures and gate assisted 4-probe structures have been designed and fabricated to measure the field effects of current crowding at the source/drain contacts of top-gate MoS2 field effect transistors. The transistors
Displaying 201 - 225 of 718