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Displaying 76 - 100 of 148

Reliability of SiC MOS Devices

June 24, 2004
Author(s)
Ranbir Singh, Allen R. Hefner Jr.
Fundamental limitations to oxide reliability are analyzed in silicon carbide based devices. A barrier height primarily determined by band offsets between metal/SiC and the dielectric, and the electric field in the dielectric results in tunneling current

Micro-Differential Scanning Calorimeter for Combustible Gas Sensing

January 1, 2004
Author(s)
Richard E. Cavicchi, G Poirier, N H. Tea, Muhammad Y. Afridi, David W. Berning, Allen R. Hefner Jr., John S. Suehle, Michael Gaitan, Stephen Semancik, Christopher B. Montgomery
A micron-scale differential scanning calorimeter (mDSC) has been produced on a silicon chip allowing for microscopic differential scanning calorimetry measurements on small samples. The device consists of a suspended rectangular microhotplate with sample

MEMS-based Embedded Sensor Virtual Components for SoC

November 25, 2003
Author(s)
Muhammad Afridi, Allen R. Hefner Jr., David W. Berning, Colleen E. Hood, Ankush Varma, Bruce Jacob, Stephen Semancik
Advancement in MEMS-based sensors brings a new challenge for system-on-a-chip (SoC) design integration where analog and digital circuits coexist on a common substrate with the actual sensing platform. Integration of these MEMS-based sensors into an SoC

EMI Characterization with Parasitic Modeling for a Permanent Magnet Motor Drive

October 12, 2003
Author(s)
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

High Speed IGBT Module Transient Thermal Response Measurements for Model Validation

October 12, 2003
Author(s)
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

The Role of Carrier Lifetime in Forward Bias Degradation of 4H-SiC PiN Diodes

October 5, 2003
Author(s)
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

Silicon Carbide Power MOSFET Model and Parameter Extraction Sequence

June 11, 2003
Author(s)
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

A Monolithic CMOS Microhotplate-based Gas Sensor System

December 1, 2002
Author(s)
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

Large Area, Ultra-high Voltage 4H-SiC PiN Rectifiers

December 1, 2002
Author(s)
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

Thermal Component Models for Electro-Thermal Analysis of Multichip Power Modules

October 24, 2002
Author(s)
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

A Monolithic Implementation of Interface Circuitry for CMOS Compatible Gas-Sensor System

July 1, 2002
Author(s)
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

Transient Heating Study of Microhotplates by Using a High-Speed Thermal Imaging System

March 1, 2002
Author(s)
Muhammad Afridi, David W. Berning, Allen R. Hefner Jr., John S. Suehle, Mona E. Zaghloul, Eric Kelley, Zharadeen R. Parrilla, Colleen E. Hood
A high-speed thermal imaging system is used to investigate the dynamic thermal behavior of MEMS-based (MicroElectroMechanical Systems) microhotplate devices. These devices are suspended microstructures fabricated in CMOS technology and are used in various

Characterization and Modeling of Silicon-Carbide Power Devices

December 1, 2001
Author(s)
Allen R. Hefner Jr., David W. Berning, Ty R. McNutt, Alan Mantooth, Jih-Sheng Lai, Ranbir Singh
New Power semiconductor devices have begun to emerge that utilize the advantages of silicon carbide (SiC). As SiC power device types are introduced, circuit performance and reliability characterization are required for system designers to adopt the new

High Temperature Characteristics of 5kV, 20 A 4H-SiC PiN Rectifiers

June 7, 2001
Author(s)
Ranbir Singh, Allen R. Hefner Jr., David W. Berning, M. Palmer
This paper reports in detail, the design, a manufactuable fabrication process, and high temperature characteristics of a 4H-SiC rectifier with a 5 kV, 20 A rating. A highly doped p-type epitaxial Anode layer and junction termination extension (JTE) were
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