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Displaying 1 - 25 of 27

Rapid, quantitative therapeutic screening for Alzheimer's enzymes enabled by optimal signal transduction with transistors

April 14, 2020
Author(s)
Son T. Le, Michelle A. Morris, Antonio Cardone, Nicholas B. Guros, Jeffery B. Klauda, Brent A. Sperling, Curt A. Richter, Harish C. Pant, Arvind Balijepalli
We show that commercially sourced n-channel silicon field-effect transistors (nFETs) operating under closed-loop control achieve a resolution of (7.2+/-0.3)x10-3 pH units with a bandwidth of 10 Hz. The results represent an 3-fold improvement in performance

Nonvolatile memory based on redox-active Ruthenium molecular monolayers

October 14, 2019
Author(s)
Kai Jiang, Sujitra Pookpanratana, Tong Ren, Sean Natoli, Brent A. Sperling, Joseph W. Robertson, Curt A. Richter, Sheng Yu, Qiliang Li
A monolayer of diruthenium molecules was self-assembled onto the silicon oxide surface in a semiconductor capacitor structure with a ‘click' reaction for nonvolatile memory applications. The attachment of the active molecular monolayer was verified by x

Characterization of bubbler performance for low-volatility liquid precursor delivery

June 27, 2019
Author(s)
James E. Maslar, William A. Kimes, Brent A. Sperling, Ravindra K. Kanjolia
The performance of a bubbler to deliver the low-volatility, liquid cobalt precursor μ2- η2-(tBu- acetylene) dicobalthexacarbonyl (CCTBA) for reduced-pressure chemical vapor deposition and atomic layer deposition processes was characterized. A relatively

Reproducible Performance Improvements to Monolayer MoS2 Transistors through Exposed Material Forming Gas Annealing

April 16, 2019
Author(s)
Nicholas B. Guros, Son T. Le, Siyuan Zhang, Brent A. Sperling, Jeffery B. Klauda, Curt A. Richter, Arvind Balijepalli
We have developed an optimized process to realize high-performance field-effect transistor (FET) arrays from large-area 2D MoS2 films with an average yield of 85 %. A central element of the technique is a new exposed film forming gas anneal (EF- FGA) that

In situ infrared spectroscopy during La2O3 ALD using La(iPrCp)3 and H2O

April 26, 2018
Author(s)
Brent A. Sperling, James E. Maslar, Sergei Ivanov
Infrared spectra have been obtained during atomic layer deposition using tris(isopropylcyclopentadienyl)lanthanum, La(iPrCp)3, and water as precursors at 160 °C and 350 °C. Gas-phase spectra of La(iPrCp)3 are additionally obtained for comparison. At low

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

Tearing and scrolling of transferred graphene

April 29, 2014
Author(s)
Guangjun Cheng, Brent A. Sperling, James E. Maslar, Curt A. Richter, Angela R. Hight Walker
We present an investigation on tearing and scrolling of the transferred graphene on a Si/SiO2 substrate. Graphene grown by chemical vapor deposition (CVD) is transferred onto a Si/SiO2 substrate using a wet polymer-mediated process. Upon the removal of

Time-resolved surface infrared spectroscopy during atomic layer deposition of TiO2 using tetrakis(dimethylamido)titanium and water

April 23, 2014
Author(s)
Brent A. Sperling, John Hoang, William A. Kimes, James E. Maslar, Kristen L. Steffens, Nhan V. Nguyen
Atomic layer deposition of titanium dioxide using tetrakis(dimethylamido)titanium (TDMAT) and water vapor is studied by reflection-absorption infrared spectroscopy (RAIRS) with a time resolution of 120 ms. Decomposition of the adsorbed TDMAT is observed

Time-resolved surface infrared spectroscopy during atomic layer deposition

September 10, 2013
Author(s)
Brent A. Sperling, John J. Hoang, William A. Kimes, James E. Maslar
This work presents a novel method for obtaining surface infrared spectra with sub-second time resolution during atomic layer deposition (ALD). Using a rapid-scan Fourier transform infrared (FT-IR) spectrometer, we obtain a series of interferograms (120 ms)

Towards clean and crackless transfer of graphene

January 2, 2012
Author(s)
Xuelei X. Liang, Brent A. Sperling, Irene G. Calizo, Guangjun Cheng, Christina Hacker, Qin Zhang, Yaw S. Obeng, Kai Yan, Hailin Peng, Qiliang Li, Xiaoxiao Zhu, Hui Yuan, Angela R. Hight Walker, Zhongfan Liu, Lianmao Peng, Curt A. Richter
We present the results of a thorough study of wet chemical methods for transferring chemical vapor deposition grown graphene from the metal growth substrate to a device compatible substrate. Based on these results, we have developed a "modified RCA clean"

In Situ Gas Phase Diagnostics for Titanium Nitride Atomic Layer Deposition

October 14, 2011
Author(s)
James E. Maslar, William A. Kimes, Brent A. Sperling
This report describes the performance of a technique for the simultaneous, rapid measurement of major gas phase species present during titanium nitride thermal atomic layer deposition involving tetrakis(dimethylamido) titanium (TDMAT) and ammonia. In this

In Situ Gas Phase Measurements During Metal Alkylamide Atomic Layer Deposition

July 12, 2011
Author(s)
James E. Maslar, William A. Kimes, Brent A. Sperling
Metal alkylamide compounds, such as tetrakis(ethylmethylamido) hafnium (TEMAH), represent a technologically important class of metalorganic precursors for the deposition of metal oxides and metal nitrides via atomic layer deposition (ALD) or chemical vapor