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Displaying 126 - 150 of 296

Reliability and Performance Limitations in SiC Power Devices

December 27, 2005
Author(s)
Ranbir Singh, Allen R. Hefner Jr.
Despite Silicon Carbide's (SiC's) high breakdown electric field, high thermal conductivity and wide bandgap, it faces certain reliability challenges when used to make conventional power device structures like power MOS-based devices, bipolar-mode diodes

Characterization System for Embedded Gas Sensor Systems-on-a-Chip

December 1, 2005
Author(s)
Muhammad Y. Afridi, Allen R. Hefner Jr., Colleen E. Hood, Richard E. Cavicchi, Stephen Semancik
A characterization system is presented for evaluating critical functions of a microhotplate-based embedded gas-sensor for system-on-a-chip applications. The system uses a virtual instrument interface to control parts-per-billion (ppb) gas concentration

Characterization of Normally-off SiC Vertical JFET Devices and Inverter Circuits

October 1, 2005
Author(s)
Jih-Sheng Lai, H. Yu, J. Zhang, Y. Li, Kuang Sheng, J.H. Zhao, Allen R. Hefner Jr.
A normally-off SiC JFETs has been characterized under static and dynamic operating conditions. Two application oriented inverter circuits were constructed for additional tests under soft- and hard-switching conditions. The single-phase soft-switching

Metrology for High-Voltage, High-Speed Silicon-Carbide Power Devices

April 4, 2005
Author(s)
Allen R. Hefner Jr., David W. Berning, Colleen E. Hood
Performance metrics and test instrumentation needs for emerging high-voltage, high-speed SiC power devices are described. Unique power device and package thermal measurement test systems and parameter extraction methods are introduced, and applied to

Electrostatic Discharge Protection For Embedded-Sensor Systems-On-a-Chip

October 8, 2004
Author(s)
Javier A. Salcedo, Juin J. Liou, Muhammad Afridi, Allen R. Hefner Jr., Ankush Varma
The robustness of Embedded-Sensor (ES) System-on-a-Chip (SoC) applications involves several design constrains that require a unique assessment. For example, space-efficient electrostatic discharge protection (ESD) must be provided to protect the CMOS

Compact Models for Silicon Carbide Power Devices

October 1, 2004
Author(s)
Ty R. McNutt, Allen R. Hefner Jr., Alan Mantooth, David W. Berning, Ranbir Singh
The development of compact silicon carbide (SiC) power semiconductor device models for circuit simulation is described. The work detailed herein has been used to model power Schottky, Merged-PiN-Schottky, PiN diode, and MOSFET models. In these models, the

Lumped-Parameter Thermal Modeling of an IPEM using Thermal Component Models

August 15, 2004
Author(s)
J J. Rodriguez, Allen R. Hefner Jr., David W. Berning, M Velez-Reyes, Madelaine H. Hernandez, Jorge Gonz?lez
A thermal model for the CPES IPEM Gen. II is presented. The selected approach is the simulation of the thermal behavior of an experimental IPEM testbed using the 1D finite difference method. An equivalent electrical network representation of the thermal

10 kV, 123 m O}-cm 2 4H-SiC Power DMOSFETs

August 1, 2004
Author(s)
Sei-Hyung Ryu, Sumi Krishnaswami, Michael O'Loughlin, James Richmond, Anant Agarwal, John W. Palmour, Allen R. Hefner Jr.
10 kV, 123 mΩ}-cm 2 Power DMOSFETs in 4H-SiC are demonstrated. A 42% reduction in R on,sp, compared to previously reported value, was achieved by using an 8 x 1014 cm-3 doped, 85 υm thick drift epilayer. An effective channel mobility of 22 cm2/Vs was

Mems-Based Embedded Sensor Virtual Components for SOC

June 24, 2004
Author(s)
Muhammad Afridi, Allen R. Hefner Jr., David W. Berning, Colleen E. Hood, Ankush Varma, Bruce Jacob, Stephen Semancik
The design and implementation of a monolithic MEMS-based (Micro Electro Mechanical Systems) gas sensor virtual component is described. A bulk micromachining technique is used to create suspended microhotplate structures. The thermal properties of the