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An insulated-gate bipolar transistor (IGBT) is a three-terminal power semiconductor device primarily used as an electronic switch which, as it was developed, came to combine high efficiency and fast switching. It switches electric power in many modern appliances: variable-frequency drives (VFDs), electric cars, trains, variable speed refrigerators, lamp ballasts, air-conditioners and even stereo systems with switching amplifiers. Since it is designed to turn on and off rapidly, amplifiers that use it often synthesize complex waveforms with pulse-width modulation and low-pass filters. In switching applications modern devices feature pulse repetition rates well into the ultrasonic range—frequencies which are at least ten times the highest audio frequency handled by the device when used as an analog audio amplifier. The IGBT combines the simple gate-drive characteristics of MOSFETs with the high-current and low-saturation-voltage capability of bipolar transistors. The IGBT combines an isolated-gate FET for the control input and a bipolar power transistor as a switch in a single device. The IGBT is used in medium- to high-power applications like switched-mode power supplies, traction motor control and induction heating. Large IGBT modules typically consist of many devices in parallel and can have very high current-handling capabilities in the order of hundreds of amperes with blocking voltages of , equating to powers of hundreds of kilowatts. The first-generation IGBTs of the 1980s and early 1990s were prone to failure through effects such as latchup (in which the device will not turn off as long as current is flowing) and secondary breakdown (in which a localized hotspot in the device goes into thermal runaway and burns the device out at high currents). Second-generation devices were much improved. The current third-generation IGBTs are even better, with speed rivaling MOSFETs, and excellent ruggedness and tolerance of overloads.〔A.Nakagawa et al., "Safe operating area for 1200-V non-latch-up bipolar-mode MOSFETs", IEEE Trans. on Electron Devices, ED-34, pp. 351–355(1987)〕 Extremely high pulse ratings of second- and third-generation devices also make them useful for generating large power pulses in areas including particle and plasma physics, where they are starting to supersede older devices such as thyratrons and triggered spark gaps. High pulse ratings and low prices on the surplus market also make them attractive to the high-voltage hobbyists for controlling large amounts of power to drive devices such as solid-state Tesla coils and coilguns. ==History== The IGBT is a semiconductor device with four alternating layers (P-N-P-N) that are controlled by a metal-oxide-semiconductor (MOS) gate structure without regenerative action. This mode of operation was first proposed by Yamagami in his Japanese patent S47-21739, which was filed in 1968. This mode of operation was first experimentally reported in the lateral four layer device (SCR) by B. W. Scharf and J. D. Plummer in 1978.〔 B.W. Scharf and J.D. Plummer, 1978 IEEE International Solid-State Circuits Conference, SESSION XVI FAM 16.6 "A MOS-Controlled Triac Devices" 〕 This mode of operation was also experimentally discovered in vertical device in 1979 by B. J. Baliga.〔 B.J. Baliga, "ENHANCEMENT- AND DEPLETION-MODE VERTICAL-CHANNEL M.O.S. GATED THYRISTORS" Electronics Letters p.645(1979)〕 The device structure was referred to as a ‘V-groove MOSFET device with the drain region replaced by a p-type Anode Region’ in this paper and subsequently as 'the insulated-gate rectifier' (IGR),〔B. J. Baliga, et al., ("The insulated gate rectifier (IGR): A new power switching device" ), IEEE International Electron Devices Meeting, Abstract 10.6, pp. 264-267, 1982.〕 the insulated-gate transistor (IGT),〔B. J. Baliga, ("Fast-switching insulated gate transistors" ), IEEE Electron Device Letters, Vol. EDL-4, pp. 452-454, 1983.〕 the conductivity-modulated field-effect transistor (COMFET)〔 and "bipolar-mode MOSFET".〔A.Nakagawa et al., "High voltage bipolar-mode MOSFETs with high current capability", Ext. Abst. of SSDM, pp. 309–312(1984)〕 Plummer filed a patent application for IGBT mode of operation in the four layer device (SCR) in 1978. USP No.4199774 was issued in 1980 and B1 Re33209〔(B1 Re33209 is attached in the pdf file of Re 33209 )〕 was reissued in 1995 for the IGBT mode operation in the four layer device (SCR). Hans W. Becke and Carl F. Wheatley invented a similar device for which they filed a patent application in 1980, and which they referred to as "power MOSFET with an anode region".〔(U. S. Patent No. 4,364,073 ), Power MOSFET with an Anode Region, issued December 14, 1982 to Hans W. Becke and Carl F. Wheatley〕 This patent has been called "the seminal patent of the insulated gate bipolar transistor."〔(【引用サイトリンク】 C. Frank Wheatley, Jr., BSEE )〕 The patent claimed "no thyristor action occurs under any device operating conditions." This substantially means that the device exhibits non-latch-up IGBT operation over the entire device operation range. Practical devices capable of operating over an extended current range were first reported by Baliga et al. in 1982.〔 A similar paper was also submitted by J. P. Russel et al. to IEEE Electron Device Letter in 1982.〔J.P. Russel et al., ("The COMFET—A new high conductance MOS-gated device" ), IEEE Electron Device Lett., vol. EDL-4, pp. 63–65, 1983〕 The applications for the device were initially regarded by the power electronics community to be severely restricted by its slow switching speed and latch-up of the parasitic thyristor structure inherent within the device. However, it was demonstrated by Baliga and also by A. M. Goodman et al. in 1983 that the switching speed could be adjusted over a broad range by using electron irradiation.〔〔A. M. Goodman et al., ("Improved COMFETs with fast switching speed and high-current capability" ), IEEE International Electron Devices Meeting Technical Digest, pp. 79–82,1983〕 This was followed by demonstration of operation of the device at elevated temperatures by Baliga in 1985.〔B. J. Baliga, ("Temperature behavior of insulated gate transistor characteristics" ), Solid State Electronics, Vol. 28, pp. 289–297, 1985.〕 Successful efforts to suppress the latch-up of the parasitic thyristor and the scaling of the voltage rating of the devices at GE allowed the introduction of commercial devices in 1983,〔Product of the Year Award: "Insulated Gate Transistor", General Electric Company, Electronics Products, 1983.〕 which could be utilized for a wide variety of applications. Complete suppression of the parasitic thyristor action and the resultant non-latch-up IGBT operation for the entire device operation range was achieved by A. Nakagawa et al. in 1984.〔A. Nakagawa et al., "Non-latch-up 1200V 75A bipolar-mode MOSFET with large ASO", IEEE International Electron Devices Meeting Technical Digest, pp.860-861,1984.〕 The non-latch-up design concept was filed for US patents.〔A.Nakagawa, H. Ohashi, Y. Yamaguchi, K. Watanabe and T. Thukakoshi, "Conductivity modulated MOSFET" (US Patent No.6025622(Feb.15, 2000) ), No.5086323 (Feb.4, 1992) and (No.4672407(Jun.9, 1987) )〕 To test the lack of latch-up, the prototype 1200V IGBTs were directly connected without any loads across a 600V constant voltage source and were switched on for 25 microseconds. The entire 600V was dropped across the device and a large short circuit current flowed. The devices successfully withstood this severe condition. This was the first demonstration of so-called "short-circuit-withstanding-capability" in IGBTs. Non-latch-up IGBT operation was ensured, for the first time, for the entire device operation range.〔A. Nakagawa et al., ("Experimental and numerical study of non-latch-up bipolar-mode MOSFET characteristics" ), IEEE International Electron Devices Meeting Technical Digest, pp. 150–153, 1985〕 In this sense, the non-latch-up IGBT proposed by Hans W. Becke and Carl F. Wheatley was realized by A. Nakagawa et al. in 1984. Products of non-latch-up IGBTs were first commercialized by Toshiba in 1985. Once the non-latch-up capability was achieved in IGBTs, it was found that IGBTs exhibited very rugged and a very large safe operating area. It was demonstrated that the product of the operating current density and the collector voltage exceeded the theoretical limit of bipolar transistors, 2 W/cm2, and reached 5 W/cm2.〔〔 The insulating material is typically made of solid polymers which have issues with degradation. There are developments that use an ion gel to improve manufacturing and reduce the voltage required. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Insulated-gate bipolar transistor」の詳細全文を読む スポンサード リンク
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