# New Cree Technology - What does it mean?



## Phredd (Mar 6, 2008)

Apparently Cree developed yet another new technology with government funding. Does this enable more efficient LEDs by eliminating reverse current flow? Can an EE please explain this in layman's terms? Cree may have an advantage since they already have the technology, but because it was developed with government funding, other companies can license the technology from the government. I don't know if that would include foreign companies.

Phredd

-----

Title: Power Switching Semiconductor Devices Including Rectifying Junction-Shunts.
Abstract: Typical applications for switching power devices (e.g., IGBT or Power MOSFET) require reverse conduction for rectification or clamping by either an internal or external diode. Because Power MOSFETs have an inherent PiN diode within the structure, this internal diode must either be made to work effetely for the rectification and clamping, or must be bypassed by an external diode. Because the inherent internal PiN diode results in majority carrier injection from the drain-body junction (PN junction at Body-to-Drift-Layer interface) it has slow reverse recovery time and may result in SiC crystal degradation. The concept of inclusion of reverse conducting SIR junction shunts provides substantial benefits by: (1) Bypassing current flow from the inherent internal drain-body junction preventing it from injecting majority carriers and thus preventing slow reverse recovery and crystal degradation, and (2) enabling current to flow for voltages lower than the drain-body junction built in potential (e.g., approximately 3 V for SiC) and thus provides lower on-state losses than a PiN diode for the lower current range condition.


----------



## evan9162 (Mar 6, 2008)

No. This has nothing to do with LEDs. This is for improving IGBTs and MOSFETs


----------

