Positive temperature coefficient of breakdown voltage in 4H-SiC pn junction rectifiers

In this work, avalanche photodiodes (APDs) were fabricated using a-plane 6H- and 4H-SiC materials to investigate their electrical and optical properties. Temperature dependence of avalanche breakdown was measured. The diode structures were fabricated with positive angle beveling and oxide passivation to ensure a uniform breakdown across the device area. Despite the apparent presence of micro-plasmas, we observed that the breakdown voltage of a-plane 6H-SiC APDs increased with temperature suggesting a positive temperature coefficient.

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Temperature Dependence of Impact Ionization Coefficients in 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.461 ◽

2014 ◽

Vol 778-780 ◽

pp. 461-466 ◽

Cited By ~ 14

Author(s):

Hiroki Niwa ◽

Jun Suda ◽

Tsunenobu Kimoto

Keyword(s):

Temperature Dependence ◽

Temperature Coefficient ◽

Breakdown Voltage ◽

Elevated Temperatures ◽

Phonon Scattering ◽

Impact Ionization ◽

Negative Temperature ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Ionization Coefficients

Impact ionization coefficients of 4H-SiC were measured at room temperature and at elevated temperatures up to 200°C. Photomultiplication measurement was done in two complementary photodiodes to measure the multiplication factors of holes (Mp) and electrons (Mn), and ionization coefficients were extracted. Calculated breakdown voltage using the obtained ionization coefficients showed good agreement with the measured values in this study, and also in other reported PiN diodes and MOSFETs. In high-temperature measurement, breakdown voltage exhibited a positive temperature coefficient and multiplication factors showed a negative temperature coefficient. Therefore, extracted ionization coefficient has decreased which can be explained by the increase of phonon scattering. The calculated temperature dependence of breakdown voltage agreed well with the measured values not only for the diodes in this study, but also in PiN diode in other literature.

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ANALYSIS OF ELECTRICAL BEHAVIOR OF SOI LDMOSFET WITH RESPECT TO TEMPERATURE AND DOPING USING T-CAD SIMULATOR

International Journal of Electronics and Electical Engineering ◽

10.47893/ijeee.2015.1156 ◽

2015 ◽

pp. 206-209

Author(s):

DEEKSHA BAJPAI ◽

AVNISH KUMAR UPADHYAY

Keyword(s):

Temperature Coefficient ◽

Leakage Current ◽

Breakdown Voltage ◽

Threshold Voltage ◽

Positive Temperature Coefficient ◽

Effect Of Temperature ◽

Positive Temperature ◽

Wireless System ◽

Current Threshold ◽

Frequency Power

In this paper, the effect of temperature variation and doping variation of p-body on various parameters like Breakdown voltage, on resistance, drain leakage current, threshold voltage etc of SOI laterally diffused MOSFET has been analyzed. Since power mosfet is designed for radio frequency power amplifiers which is used in wireless system-on-a-chip applications. The device is fabricated on a thin-film SOI wafer in order to reduce the leakage current and also prohibit the formation of parasitic diode with substrate. On the basis of analysis we are able to prove that this SOI LDMOSFET has +ve temperature coefficient for breakdown voltage, negative temp coefficient for threshold voltage, positive temperature coefficient for on resistance and +ve temperature coefficient for drain leakage current.

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The Temperature Dependent Breakdown Voltage For 4H- and 6H-SiC Diodes

MRS Proceedings ◽

10.1557/proc-622-t6.4.1 ◽

2000 ◽

Vol 622 ◽

Cited By ~ 3

Author(s):

Y. S. Lee ◽

M. K. Han ◽

Y. I. Choi

Keyword(s):

High Temperature ◽

Temperature Coefficient ◽

Breakdown Voltage ◽

Impact Ionization ◽

Positive Temperature Coefficient ◽

Positive Temperature ◽

Ionization Coefficient ◽

Temperature Dependent ◽

Increasing Temperature ◽

Temperature Applications

ABSTRACTThe breakdown voltages of 6H- and 4H-SiC rectifiers as function of temperature were modeled analytically in both non-reachthrough diode and reachthrough diode. The breakdown voltage was derived by the ionization integral employing accurate hole impact ionization coefficient. The breakdown voltage of SiC rectifiers was increased with increasing temperature and the positive temperature coefficient of breakdown voltage indicates that SiC rectifiers are suitable for high temperature applications. The breakdown voltages of both 6H- and 4H-SiC diodes were increased by M(T)-1/4 in NRDs and M(T)-1/8 in RDs.

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High Voltage, Low On-Resistance 4H-SiC BJTs with Improved Junction Termination Extension

Materials Science Forum ◽

10.4028/www.scientific.net/msf.679-680.706 ◽

2011 ◽

Vol 679-680 ◽

pp. 706-709 ◽

Cited By ~ 7

Author(s):

Reza Ghandi ◽

Benedetto Buono ◽

Martin Domeij ◽

Carl Mikael Zetterling ◽

Mikael Östling

Keyword(s):

Temperature Coefficient ◽

Breakdown Voltage ◽

Surface Passivation ◽

Negative Temperature ◽

Positive Temperature Coefficient ◽

Bipolar Transistors ◽

Current Gain ◽

Positive Temperature ◽

Large Area ◽

Dc Current

In this work, implantation-free 4H-SiC bipolar transistors with two-zone etched-JTE and improved surface passivation are fabricated. This design provides a stable open-base breakdown voltage of 2.8 kV which is about 75% of the parallel plane breakdown voltage. The small area devices shows a maximum dc current gain of 55 at Ic=0.33 A (JC=825 A/cm2) and VCESAT = 1.05 V at Ic = 0.107 A that corresponds to a low ON-resistance of 4 mΩ•cm2. The large area device shows a maximum dc current gain of 52 at Ic = 9.36 A (JC=312 A/cm2) and VCESAT = 1.14 V at Ic = 5 A that corresponds to an ON-resistance of 6.8 mΩ•cm2. Also these devices demonstrate a negative temperature coefficient of the current gain (β=26 at 200°C) and positive temperature coefficient of the ON-resistance (RON = 10.2 mΩ•cm2).

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