scispace - formally typeset
Search or ask a question
Journal ArticleDOI

High breakdown voltage AlGaN-GaN power-HEMT design and high current density switching behavior

01 Dec 2003-IEEE Transactions on Electron Devices (IEEE)-Vol. 50, Iss: 12, pp 2528-2531
TL;DR: AlGaN-GaN power high-electron mobility transistors (HEMTs) with 600-V breakdown voltage are fabricated and demonstrated as switching power devices for motor drive and power supply applications.
Abstract: AlGaN-GaN power high-electron mobility transistors (HEMTs) with 600-V breakdown voltage are fabricated and demonstrated as switching power devices for motor drive and power supply applications. The fabricated power HEMT realized the high breakdown voltage by optimized field plate technique and the low on-state resistance of 3.3 m/spl Omega/cm/sup 2/, which is 20 times lower than that or silicon MOSFETs, thanks to the high critical field of GaN material and the high mobility in 2DEG channel. The fabricated devices also demonstrated the high current density switching of 850 A/cm/sup 2/ turn-off. These results show that AlGaN-GaN power-HEMTs are one of the most promising candidates for future switching power device for power electronics applications.
Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, a gate injection transistor (GIT) was proposed to increase the electron density in the channel, resulting in a dramatic increase of the drain current owing to the conductivity modulation.
Abstract: We have developed a normally-off GaN-based transistor using conductivity modulation, which we call a gate injection transistor (GIT). This new device principle utilizes hole-injection from the p-AlGaN to the AlGaN/GaN heterojunction, which simultaneously increases the electron density in the channel, resulting in a dramatic increase of the drain current owing to the conductivity modulation. The fabricated GIT exhibits a threshold voltage of 1.0 V with a maximum drain current of 200 mA/mm, in which a forward gate voltage of up to 6 V can be applied. The obtained specific ON-state resistance (RON . A) and the OFF-state breakdown voltage (BV ds) are 2.6 mOmega . cm2 and 800 V, respectively. The developed GIT is advantageous for power switching applications.

855 citations


Cites background from "High breakdown voltage AlGaN-GaN po..."

  • ...Most of the reported AlGaN/GaN HFETs are the normally-on type taking advantage of the inherent high sheet carrier density caused by the built-in polarization electric field [1], [ 2 ]....

    [...]

Journal ArticleDOI
TL;DR: In this paper, a novel approach was proposed to fabricate high-performance enhancement mode (E-mode) AlGaN/GaN HEMTs based on fluoride-based plasma treatment of the gate region.
Abstract: We report a novel approach in fabricating high-performance enhancement mode (E-mode) AlGaN/GaN HEMTs. The fabrication technique is based on fluoride-based plasma treatment of the gate region in AlGaN/GaN HEMTs and post-gate rapid thermal annealing with an annealing temperature lower than 500/spl deg/C. Starting with a conventional depletion-mode HEMT sample, we found that fluoride-based plasma treatment can effectively shift the threshold voltage from -4.0 to 0.9 V. Most importantly, a zero transconductance (g/sub m/) was obtained at V/sub gs/=0 V, demonstrating for the first time true E-mode operation in an AlGaN/GaN HEMT. At V/sub gs/=0 V, the off-state drain leakage current is 28 /spl mu/A/mm at a drain-source bias of 6 V. The fabricated E-mode AlGaN/GaN HEMTs with 1 /spl mu/m-long gate exhibit a maximum drain current density of 310 mA/mm, a peak g/sub m/ of 148 mS/mm, a current gain cutoff frequency f/sub T/ of 10.1 GHz and a maximum oscillation frequency f/sub max/ of 34.3 GHz.

629 citations

Journal ArticleDOI
Wataru Saito1, Yoshiharu Takada1, Masahiko Kuraguchi1, Kunio Tsuda1, Ichiro Omura1 
TL;DR: In this article, a recessed-gate structure was proposed to realize normally off operation of high-voltage AlGaN/GaN high-electron mobility transistors (HEMTs) for power electronics applications.
Abstract: A recessed-gate structure has been studied with a view to realizing normally off operation of high-voltage AlGaN/GaN high-electron mobility transistors (HEMTs) for power electronics applications. The recessed-gate structure is very attractive for realizing normally off high-voltage AlGaN/GaN HEMTs because the gate threshold voltage can be controlled by the etching depth of the recess without significant increase in on-resistance characteristics. With this structure the threshold voltage can be increased with the reduction of two-dimensional electron gas (2DEG) density only under the gate electrode without reduction of 2DEG density in the other channel regions such as the channel between drain and gate. The threshold-voltage increase was experimentally demonstrated. The threshold voltage of fabricated recessed-gate device increased to -0.14 V while the threshold voltage without the recessed-gate structure was about -4 V. The specific on-resistance of the device was maintained as low as 4 m/spl Omega//spl middot/cm/sup 2/ and the breakdown voltage was 435 V. The on-resistance and the breakdown voltage tradeoff characteristics were the same as those of normally on devices. From the viewpoint of device design, the on-resistance for the normally off device was modeled using the relationship between the AlGaN layer thickness under the gate electrode and the 2DEG density. It is found that the MIS gate structure and the recess etching without the offset region between recess edge and gate electrode will further improve the on-resistance. The simulation results show the possibility of the on-resistance below 1 m/spl Omega//spl middot/cm/sup 2/ for normally off AlGaN/GaN HEMTs operating at several hundred volts with threshold voltage up to +1 V.

516 citations


Cites background from "High breakdown voltage AlGaN-GaN po..."

  • ...Whereas most of the AlGaN/GaN HEMTs demonstrated so far had normally on (depletion mode) characteristics with gate threshold voltage under V [6], [7], normally off (enhancement mode) characteristics are strongly required for...

    [...]

Journal ArticleDOI
TL;DR: In this article, a self-aligned "slant-field-plate" technology is presented as an improvement over the discrete multiple field plates for high breakdown voltage AlGaN/GaN HEMTs.
Abstract: A self-aligned "slant-field-plate" technology is presented as an improvement over the discrete multiple field plates for high breakdown voltage AlGaN/GaN HEMTs. Devices were tested in Fluorinert to eliminate the breakdown of air, which was identified to limit the breakdown voltage in AlGaN/GaN HEMTs. A single integrated field plate, which is self-aligned with the gate, is shown to support more than a kilovolt breakdown voltage (Vbr up to 1900 V was measured with Fluorinert). Devices made with this technology show a good large signal-frequency behavior. Various issues regarding breakdown measurements and interpretation of measurement results are presented

446 citations


Cites background from "High breakdown voltage AlGaN-GaN po..."

  • ...Breakdown voltages as high as 900 V with low ON-resistance Ron have been demonstrated by using multiple field plates [2] and backside field plate [3]....

    [...]

Journal ArticleDOI
TL;DR: In this article, the performance of high voltage rectifiers and enhancement-mode metal-oxide field effect transistors on Ga2O3 has been evaluated and shown to benefit from the larger critical electric field relative to either SiC or GaN.
Abstract: Gallium oxide (Ga2O3) is emerging as a viable candidate for certain classes of power electronics with capabilities beyond existing technologies due to its large bandgap, controllable doping, and the availability of large diameter, relatively inexpensive substrates. These applications include power conditioning systems, including pulsed power for avionics and electric ships, solid-state drivers for heavy electric motors, and advanced power management and control electronics. Wide bandgap (WBG) power devices offer potential savings in both energy and cost. However, converters powered by WBG devices require innovation at all levels, entailing changes to system design, circuit architecture, qualification metrics, and even market models. The performance of high voltage rectifiers and enhancement-mode metal-oxide field effect transistors benefits from the larger critical electric field of β-Ga2O3 relative to either SiC or GaN. Reverse breakdown voltages of over 2 kV for β-Ga2O3 have been reported, either with or without edge termination and over 3 kV for a lateral field-plated Ga2O3 Schottky diode on sapphire. The metal-oxide-semiconductor field-effect transistors fabricated on Ga2O3 to date have predominantly been depletion (d-mode) devices, with a few demonstrations of enhancement (e-mode) operation. While these results are promising, what are the limitations of this technology and what needs to occur for it to play a role alongside the more mature SiC and GaN power device technologies? The low thermal conductivity might be mitigated by transferring devices to another substrate or thinning down the substrate and using a heatsink as well as top-side heat extraction. We give a perspective on the materials’ properties and physics of transport, thermal conduction, doping capabilities, and device design that summarizes the current limitations and future areas of development. A key requirement is continued interest from military electronics development agencies. The history of the power electronics device field has shown that new technologies appear roughly every 10-12 years, with a cycle of performance evolution and optimization. The older technologies, however, survive long into the marketplace, for various reasons. Ga2O3 may supplement SiC and GaN, but is not expected to replace them.

348 citations

References
More filters
Journal ArticleDOI
TL;DR: In this paper, the authors review recent trends in power semiconductor device technology that are leading to improvements in power losses for power electronic systems and predict that silicon carbide based switches will begin to displace these silicon devices.
Abstract: This paper reviews recent trends in power semiconductor device technology that are leading to improvements in power losses for power electronic systems. In the case of low voltage ( 100 V) power rectifiers, the silicon P-i-N rectifier continues to dominate but significant improvements are expected by the introduction of the silicon MPS rectifier followed by the GaAs and SiC based Schottky rectifiers. Equally important developments are occurring in power switch technology. The silicon bipolar power transistor has been displaced by silicon power MOSFETs in low voltage ( 100 V) systems. The process technology for these MOS-gated devices has shifted from V-MOS in the early 1970s to DMOS in the 1980s, with more recent introduction of the UMOS technology in the 1990s. For the very high power systems, the thyristor and GTO continue to dominate, but significant effort is underway to develop MOS-gated thyristors (MCTs, ESTs, DG-BRTs) to replace them before the turn of the century. Beyond that time frame, it is projected that silicon carbide based switches will begin to displace these silicon devices.

507 citations


"High breakdown voltage AlGaN-GaN po..." refers background in this paper

  • ...OWER SEMICONDUCTOR switching devices with breakdown voltages of several hundred volts have been studied with a view to reducing the power loss for switching mode power supplies and inverter systems [ 1 ]....

    [...]

Journal ArticleDOI
TL;DR: In this article, a critical evaluation of the performance capabilities of various wide bandgap semiconductors for high power and high frequency unipolar electronic devices is presented, and seven different figures of merit have been analyzed.
Abstract: This paper presents a critical evaluation of the performance capabilities of various wide bandgap semiconductors for high power and high frequency unipolar electronic devices. Seven different figures of merit have been analyzed. Theoretical calculations show that besides diamond and SiC, compounds like AlN, GaN, InN, and ZnO, and the intermetallics (Ga/sub x/In/sub 1-x/N, Al/sub x/In/sub 1-x/N, Al/sub x/Ga/sub 1-x/N, and (AlN)/sub x/(SiC)/sub 1-x/) offer several orders of magnitude improvement in the on-resistance and in the potential for successful operation at higher temperatures. >

473 citations


"High breakdown voltage AlGaN-GaN po..." refers background in this paper

  • ...For more dramatic reduction of the on-resistance, AlGaN‐GaN heterostructure devices are attractive, due to high carrier mobility in two-dimensional electron gas (2DEG) channel and large critical electric field [ 4 ]‐[6]....

    [...]

Proceedings ArticleDOI
06 Dec 1998
TL;DR: In this article, the authors proposed a new device concept for high voltage power devices based on charge compensation in the drift region of the transistor, which achieved a shrink factor of 5 versus the actual state of the art in power MOSFETs.
Abstract: For the first time a new device concept for high voltage power devices has been realized in silicon. Our 600 V-COOLMOS/sup TM/ reaches an area specific on-resistance of typically 3.5 /spl Omega//spl middot/mm/sup 2/. Our technology thus offers a shrink factor of 5 versus the actual state of the art in power MOSFETs. The device concept is based on charge compensation in the drift region of the transistor. We increase the doping of the vertical drift region roughly by one order of magnitude and counterbalance this additional charge by the implementation of fine structured columns of the opposite doping type. The blocking voltage of the transistor remains thus unaltered. The charge compensating columns do not contribute to the current conduction during the turn-on state. Nevertheless the drastically increased doping of the drift region allows the above mentioned reduction of the on-resistance.

464 citations


"High breakdown voltage AlGaN-GaN po..." refers background in this paper

  • ...In addition, superjunction MOSFETs have broken through the Si-limit and achieved the on-resistance of 35 m cm for 600-V class devices [ 3 ]....

    [...]

Journal ArticleDOI
Yuji Ando1, Y. Okamoto1, H. Miyamoto1, T. Nakayama1, T. Inoue1, Masaaki Kuzuhara1 
TL;DR: In this paper, a 1mm-wide field modulating plate (FP) was used to achieve a power density of 10.3 W with a linear gain of 18.0 dB and a power added efficiency of 47.3% at 2 GHz.
Abstract: AlGaN-GaN heterojunction field-effect transistors (HFETs) with a field modulating plate (FP) were fabricated on an SiC substrate. The gate-drain breakdown voltage (BV/sub gd/) was significantly improved by employing an FP electrode, and the highest BV/sub gd/ of 160 V was obtained with an FP length (L/sub FP/) of 1 /spl mu/m. The maximum drain current achieved was 750 mA/mm, together with negligibly small current collapse. A 1-mm-wide FP-FET (L/sub FP/=1 /spl mu/m) biased at a drain voltage of 65 V demonstrated a continuous wave saturated output power of 10.3 W with a linear gain of 18.0 dB and a power-added efficiency of 47.3% at 2 GHz. To our knowledge, the power density of 10.3 W/mm is the highest ever achieved for any FET of the same gate size.

352 citations


"High breakdown voltage AlGaN-GaN po..." refers result in this paper

  • ...Fig. 3(a) shows the relation between the breakdown voltage and the field plate length . Although the crystal quality and surface state were not especially improved in the fabricated device, the simulation results show good agreement with the experimental results, and the relation between the breakdown voltage and shows same tendency with the previous experimental results [ 13 ]....

    [...]

Journal ArticleDOI
TL;DR: In this paper, a GaN high electron mobility transistors (HEMTs) were fabricated using an overlapping-gate technique in which the drain-side edge of the metal gate overlaps on a high breakdown and high dielectric constant dielectrics.
Abstract: GaN high electron mobility transistors (HEMTs) were fabricated using an overlapping-gate technique in which the drain-side edge of the metal gate overlaps on a high breakdown and high dielectric constant dielectric. The overlapping structure reduces the electric field at the drain-side gate edge, thus increasing the breakdown of the device. A record-high three-terminal breakdown figure of 570 V was achieved on a HEMT with a gate-drain spacing of 13 /spl mu/m. The source-drain saturation current was 500 mA/mm and the extrinsic transconductance 150 mS/mm.

344 citations


"High breakdown voltage AlGaN-GaN po..." refers background or result in this paper

  • ...Since the source/drain contact area dominates the fabricated device area, the on-resistance was larger than the previous reported data [7], [ 8 ]....

    [...]

  • ...The field plate is placed over the gate electrode and the edge of the field plate must be closer to the drain than the gate electrode edge so that the electric field concentration near the gate edge is efficiently eased and the electric field rather uniformly distributes between gate and drain electrodes [ 8 ]....

    [...]