Active solid-state devices (e.g. – transistors – solid-state diode – Field effect device – Having insulated electrode
Reexamination Certificate
2000-05-05
2003-09-30
Wojciechowicz, Edward (Department: 2815)
Active solid-state devices (e.g., transistors, solid-state diode
Field effect device
Having insulated electrode
C257S379000, C257S391000, C257S544000
Reexamination Certificate
active
06627961
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to MOSgated transistors and more specifically relates to a hybrid transistor consisting of the parallel connection of an IGBT and a power MOSFET.
BACKGROUND OF THE INVENTION
MOSgated transistors such as power MOSFETs and Insulated Gate Bipolar Transistors (IGBTs) are well known and have numerous advantages over conventional junction type bipolar transistors, including a simpler drive circuit. However, in certain applications, for example, for the drive of a CRT or TV deflection coil, a high voltage MOSFET has too high an on-resistance, while an IGBT forward conduction characteristic does not provide the necessary linearity near zero voltage and zero current.
It would be desirable to provide a MoSgated device for use in high voltage (for example, 1,500 volts) circuits and which exhibit good linear behavior at low voltage and low current.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the invention, a parallel connected power MOSFET and IGBT are used to define a high voltage MOSgated transistor which will have the low forward voltage drop of the IGBT and the linearity of the MOSFET at low voltage whereby the device can be used in place of a bipolar transistor in a TV deflection coil drive circuit or the like.
The novel device can be implemented by a copacked IGBT and power MOSFET die in a common package, as in the manner of the Schottky diode and MOSFET die in U.S. Pat. No. 5,814,884; or the MOSFET and IGBT can be integrated into a common die. In either case, the total MOSFET area is preferably about 50% that of the IGBT area and can range from 10% to 100%.
In a preferred integrated embodiment of the invention, a conventional D-MOS structure is formed on the top surface of an N
−
silicon die. The D-MOS structure spaced bases are then aligned vertically with alternate N
+
MOSFET contact regions and P
+
IGBT collector regions. The N
+
contact regions and P
+
collector regions are preferably spaced by about a 1 minority carrier diffusion length. These regions may be activated as by a laser anneal. A single bottom contact, preferably aluminum, then contacts the bottom regions to complete the integrated device.
REFERENCES:
patent: 4901127 (1990-02-01), Chow et al.
patent: 5178370 (1993-01-01), Clark et al.
patent: 5569982 (1996-10-01), Nadd
patent: 5689208 (1997-11-01), Nadd
patent: 5814884 (1998-09-01), Davis et al.
patent: 5851857 (1998-12-01), Kelberlau et al.
patent: 5900662 (1999-05-01), Frisina et al.
Dutta Ranadeep
Francis Richard
Ng Chiu
Wood Peter
International Rectifier Corporation
Ostrolenk Faber Gerb & Soffen, LLP
Wojciechowicz Edward
LandOfFree
Hybrid IGBT and MOSFET for zero current at zero voltage does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hybrid IGBT and MOSFET for zero current at zero voltage, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hybrid IGBT and MOSFET for zero current at zero voltage will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3062576