ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
SiC MOSFETs have very large interface trap densities which degrade deviceperformance. The effect of traps on inversion layer mobility and inversion charge concentration hasbeen studied, and mobility models suitable for inclusion in Drift-Diffusion simulators have beendeveloped for steady state operation of SiC MOSFET devices. Here, we attempt to model thetransient behavior of SiC MOSFETs, and at the same time, extract the time constants for the fillingand emptying of interface traps. As compared to the inversion layer, interface traps in SiCMOSFETs are slow in reacting to change in gate bias. So, at the positive edge of a gate pulse, wesee a large current in the MOSFET, which then decays slowly to the steady state value as theinterface traps fill up. We have developed a generation/recombination model for minority carriers ina SiC MOSFET based on the Shockley-Read-Hall recombination model for electrons and holes. Inour model, the generation/recombination takes place between minority carriers in the inversionlayer, and the traps at the SiC-SiO2 interface. Comparing our simulated current vs. time curves toexperiment, we have been able to extract time constants for the filling and emptying of traps at theSiC-SiO2 interface
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/17/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.556-557.847.pdf
Permalink