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A near-ambient, variable-temperature noise standard whose physical temperature can be accurately measured was constructed and then measured with the NIST total-power radiometer to test the accuracy of radiometer measurements in the temperature range of 263
Ty R. McNutt, Allen R. Hefner Jr., Alan Mantooth, J L. Duliere, David W. Berning, Ranbir Singh
Dynamic electrothermal circuit simulator models are developed for silicon carbide power diodes. The models accurately describe the temperature dependence of on-state characteristics and reverse-recovery switching waveforms. The models are verified for the
Anna Clark, Anthony Williams, Steve Ruggiero, Marcel L. van den Berg, Joel N. Ullom
We demonstrate a thin-film, solid-state refrigerator based on the removal of hot electrons from a metal by quantum-mechanical tunneling. We have halved the electronic temperature in a macroscopic film from 260 mK to near 130 mK. Both the cooling power and
Steve Ruggiero, Anthony Williams, W. H. Rippard, A. Clarke, Steven Deiker, Leila R. Vale, Joel N. Ullom
We discuss results on the superconducting and electron-transport properties of Mn doped Al produced by sputter deposition. The critical temperature of Al has been systematically reduced to below 50 mK by doping with 1000-3000 ppm Mn. Values of the α
Matthew Shaw, Giovanni Di Giuseppe, A. Sergeinko, Bahaa E. A. Saleh, Malvin C. Teich, Aaron J. Miller, Sae Woo Nam
The seminal experiment carried out by Hong, Ou, and Mandel some fifteen years ago is one of the most important in the annals of quantum optics. This experiment demonstrated that two indistinguishable photons incident on a simple beam splitter interfere in
Xudong Huang, Pepa Elton, Jih-Sheng Lai, Allen R. Hefner Jr., David W. Berning, Shaotang Chen, Thomas Nehl
In this paper , a permanent magnet ac motor drive is tested extensively, and the prominent frequencies are identified for their relationship with the noise sources and their propagation paths. Switching characteristics of the power MOSFETs are evaluated
David W. Berning, John V. Reichl, Allen R. Hefner Jr., Mora Hernandez, Colleen E. Hood, Jih-Sheng Lai
A measurement system operates a multi-chip insulated gate bipolar transistor (IGBT) that is part of an integrated power electronic module (IPEM) in a high-pulsed-power linear mode for validation of dynamic thermal models. It is found that the gate-cathode
Allen R. Hefner Jr., Ty R. McNutt, David W. Berning, Ranbir Singh, Adwoa Akuffo
Abstract. The role of excess carrier lifetime reduction in the mechanism for on-state voltage (Vf) degradation of high voltage 4H-SiC PiN diodes is investigated. A method is developed to electrically monitor the emitter, base, and end region excess carrier
Nhan Van Nguyen, Jin-Ping Han, Yong Jai Cho, Wenjuan Zhu, Zhijiong Luo, T P. Ma
In this report, we use vacuum ultraviolet spectroscopic ellipsometry (VUV-SE) to determine the optical as well as structural properties of high-k metal oxides, in particular, of Hafnium Aluminates and Titanium Aluminates. Two sets of samples consisting of
Carl D. Reintsema, Joern Beyer, Sae Woo Nam, Steven Deiker, Gene C. Hilton, Kent D. Irwin, Joel N. Ullom, Leila R. Vale, Michael MacIntosh
We discuss the implementation of a time-division SQUID multiplexing system for the instrumentation of large-format transition-edge sensors (TES) arrays. We cover design and integration issues concerning cryogenic SQUID multiplexers and amplifiers, signal
Ty R. McNutt, Allen R. Hefner Jr., Alan Mantooth, David W. Berning, Sei-Hyung Ryu
A compact circuit simulator model is used to describe the performance of a 2000-V, 5-A 4-H Silicon Carbide (SiC) power DiMOSFET and to perform a detailed comparison with the performance of a widely used 400-V, 5-A Silicon (Si) power MOSFET. The model's
Uwe Arz, Dylan F. Williams, Dave K. Walker, Luoh A, Hartmut Grabinski, Andreas Weisshaary
New broadband closed-form expressions for the frequencydependent impedance parameters of asymmetric coupled coplanar interconnects on a conductive silicon substrate are presented. The closed-form expressions are based on a complex image approach that
David B. Newell, Edwin R. Williams, John A. Kramar, Jon R. Pratt, Douglas T. Smith
The National Institute of Standards and Technology (NIST) has launched a five-year Micro-force Realization and Measurement project focusing on the development of an instrument and laboratory capable of realizing and measuring the SI unit of force below
This is a summary of recent efforts conducted under the auspices of the American National Standards Institute (ANSI) Accredited Standards Committee C63, Sub-committee 1, working group 1-13.2. The main purpose of this group is to assess the applicability of
Muhammad Afridi, John S. Suehle, Mona E. Zaghloul, David W. Berning, Allen R. Hefner Jr., Richard E. Cavicchi, Stephen Semancik, C B. Montgomery, C J. Taylor
A monolithic CMOS microhotplate-based conductance type gas sensor system is described. A bulk micromachining technique is used to create suspended microhotplate structures. The thermal properties of the microhotplates include a one-millisecond thermal time
Ranbir Singh, Kenneth G. Irvine, D C. Capell, James Richmond, David W. Berning, Allen R. Hefner Jr., John W. Palmour
This paper reports the design, fabrication, and high temperature characteristics of 1 mm 2, 4 mm 2, and 9 mm 2 4H-SiC rectifiers with 6 kV, 5 kV, and 10 kV blocking voltage respectively. These results were obtained from two lots in an effort to increase
We present results for uncertainties in noise-parameter measurements, obtained using a Monte Carlo simulation of the measurements. Sets of data were generated to simulate measurements on a low-noise amplifier, with given uncertainties in the underlying
J J. Rodriguez, John V. Reichl, Zharadeen R. Parrilla, Allen R. Hefner Jr., David W. Berning, M Velez-Reyes, Jih-Sheng Lai
Thermal component models are developed for multi-chip IGBT power electronic modules (PEM) and associated high-power converter heatsinks. The models are implemented in SABER and are combined with the electro-thermal IGBT and diode models to simulate the
This paper reports the formulation and results of a Monte Carlo study of uncertainties in noise-parameter measurements. The simulator permits the computation of the dependence of the uncertainty in the noise parameters on uncertainties in the underlying
Ty R. McNutt, Allen R. Hefner Jr., Alan Mantooth, J L. Duliere, David W. Berning, Ranbir Singh
A detailed parameter extraction sequence for Silicon Carbide (SiC) power diode models is presented. The sequence is applicable to any SiC diode technology. Also, the model is demonstrated for a 1.5-kV, 10-A SiC Merged PiN Schottky (MPS); 5-kV, 20-A PiN; a
Muhammad Afridi, John S. Suehle, Mona E. Zaghloul, David W. Berning, Allen R. Hefner Jr., Stephen Semancik, Richard E. Cavicchi
A monolithic CMOS micro-gas-sensor system, designed and fabricated in a standard CMOS process, is described. The gas-sensor system incorporates an array of four microhotplate-based gas-sensing structures. The system utilizes a thin film of tin-oxide (SnO 2
This paper reports results for uncertainties obtained using a Monte Carlo simulation of noise-parameter measurements. The simulator permits the computation of the dependence of the uncertainty in the noise parameters on uncertainties in the underlying
Mark H. Weatherspoon, Lawrence P. Dunleavy, Ali Boudiaf, James P. Randa
A new one-port noise temperature measurement technique is presented that uses receiver noise parameters for error correction. Improved accuracy in one-port noise temperature measurements made with commercial systems is demonstrated without using isolators
Carl Eklund, Roger Marks, K. L. Stanwood, S X. Wang
The broadband wireless access industry, which provides high-rate network connections to stationary sites, has matured to the point at which it now has a standard for second-generation wireless metropolitan area networks. IEEE Standard 802.16, with its