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SCIENCE CHINA Information Sciences, Volume 62, Issue 6: 062403(2019) https://doi.org/10.1007/s11432-018-9503-9

Simulation of a high-performance enhancement-mode HFET with back-to-back graded AlGaN layers

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  • ReceivedFeb 9, 2018
  • AcceptedJun 21, 2018
  • PublishedJan 16, 2019

Abstract

A novel three-dimensional hole gas (3DHG)enhancement-mode (E-mode) heterostructure field-effect transistor (HFET) isproposed and investigated. It features back-to-back graded AlGaN (BGA)barrier layers consisting of a positive-graded AlGaN layer and anegative-graded AlGaN layer, which form polarization gradient andsubsequently induce the three-dimensional electron gas (3DEG) and 3DHG inthe positive- and negative-graded AlGaN layers, respectively. The source anddrain are located at the same side of the metal-insulator-semiconductor(MIS) trench gate, and the source is in contact with the HfO$_{2}$ gateinsulator. First, the on-state current is significantly improved owing tothe high-density 3DEG in the positive-graded AlGaN. Next, the verticalconductive channel between the source and 3DEG is blocked by the 3DHG,thereby realizing the E-mode. The threshold voltage ($V_{\rm~th})$ can bemodulated by a partial doping conductive channel. Subsequently, a highbreakdown voltage (BV) is obtained, because the polarization junction formedby the polarization charges assists in depleting the drift region in theoff-state. Next, the BGA-HFET is smaller than the conventional HFET(Con-HFET) owing to the special location of the source. The BV of theproposed HFET sharply increases to 919 V from 39 V of the Con-HFET with thesame gate-drain spacing, and the saturation drain current is increased by103.5%


Acknowledgment

This work was supported in part by National Natural Science Foundation of China (Grant Nos. 51677021, 61234006), National Defense Science and Technology Project Foundation of China (Grant No. 1100395), and Fundamental Research Funds for the Central Universities (Grant No. ZYGX2014Z006).


References

[1] Chow T P, Tyagi R. Wide bandgap compound semiconductors for superior high-voltage unipolar power devices. IEEE Trans Electron Devices, 1994, 41: 1481-1483 CrossRef ADS Google Scholar

[2] Mishra U K, Parikh P, Yi-Feng Wu P. AlGaN/GaN HEMTs-an overview of device operation and applications. Proc IEEE, 2002, 90: 1022-1031 CrossRef Google Scholar

[3] Micovic M, Kurdoghlian A, Hashimoto P, et al. GaN HFET for W-band power applications. In: Proceedings of the International Electron Devices Meeting (IEDM), San Francisco, 2006. 425--427. Google Scholar

[4] Zhou Q, Chen W, Liu S. Schottky-Contact Technology in InAlN/GaN HEMTs for Breakdown Voltage Improvement. IEEE Trans Electron Devices, 2013, 60: 1075-1081 CrossRef ADS Google Scholar

[5] Ambacher O, Smart J, Shealy J R. Two-dimensional electron gases induced by spontaneous and piezoelectric polarization charges in N- and Ga-face AlGaN/GaN heterostructures. J Appl Phys, 1999, 85: 3222-3233 CrossRef ADS Google Scholar

[6] Ohmaki Y, Tanimoto M, Akamatsu S. Enhancement-Mode AlGaN/AlN/GaN High Electron Mobility Transistor with Low On-State Resistance and High Breakdown Voltage. Jpn J Appl Phys, 2006, 45: L1168-L1170 CrossRef ADS Google Scholar

[7] Saito W, Takada Y, Kuraguchi M. Recessed-Gate Structure Approach Toward Normally Off High-Voltage AlGaN/GaN HEMT for Power Electronics Applications. IEEE Trans Electron Devices, 2006, 53: 356-362 CrossRef ADS Google Scholar

[8] Uemoto Y, Hikita M, Ueno H, et al. A normally-off AlGaN/GaN transistor with R$_{on}$A=2.6 m$\Omega~\cdot~$cm$^{2}$ and BV$_{ds}$=640V using conductivity modulation. In: Proceedings of the International Electron Devices Meeting (IEDM), San Francisco, 2006. 1--4. Google Scholar

[9] Yong Cai , Yugang Zhou , Chen K J. High-Performance Enhancement-Mode AlGaN/GaN HEMTs Using Fluoride-Based Plasma Treatment. IEEE Electron Device Lett, 2005, 26: 435-437 CrossRef ADS Google Scholar

[10] Xiong J, Yang C, Wei J. Novel high voltage RESURF AlGaN/GaN HEMT with charged buffer layer. Sci China Inf Sci, 2016, 59: 042410 CrossRef Google Scholar

[11] Kim K W, Jung S D, Kim D S. Effects of TMAH Treatment on Device Performance of Normally Off $\hbox{Al}_{2}\hbox{O}_{3}/\hbox{GaN}$ MOSFET. IEEE Electron Device Lett, 2011, 32: 1376-1378 CrossRef ADS Google Scholar

[12] Saito W, Omura I, Ogura T. Theoretical limit estimation of lateral wide band-gap semiconductor power-switching device. Solid-State Electron, 2004, 48: 1555-1562 CrossRef ADS Google Scholar

[13] Lee J G, Lee H J, Cha H Y. Field Plated AlGaN/GaN-on-Si HEMTs for High Voltage Switching Applications. J Korean Phy Soc, 2011, 59: 2297-2300 CrossRef ADS Google Scholar

[14] Karmalkar S, Jianyu Deng S, Shur M S. RESURF AlGaN/GaN HEMT for high voltage power switching. IEEE Electron Device Lett, 2001, 22: 373-375 CrossRef ADS Google Scholar

[15] Nakajima A, Sumida Y, Dhyani M H. GaN-Based Super Heterojunction Field Effect Transistors Using the Polarization Junction Concept. IEEE Electron Device Lett, 2011, 32: 542-544 CrossRef ADS Google Scholar

[16] Yang C, Xiong J, Wei J. Analytical model and new structure of the enhancement-mode polarization-junction HEMT with vertical conduction channel. Superlattices MicroStruct, 2016, 92: 92-99 CrossRef ADS Google Scholar

[17] Jena D, Heikman S, Green D. Realization of wide electron slabs by polarization bulk doping in graded III-V nitride semiconductor alloys. Appl Phys Lett, 2002, 81: 4395-4397 CrossRef ADS Google Scholar

[18] Rajan S, Xing H, DenBaars S. AlGaN/GaN polarization-doped field-effect transistor for microwave power applications. Appl Phys Lett, 2004, 84: 1591-1593 CrossRef ADS Google Scholar

[19] Simon J, Wang A K, Xing H. Carrier transport and confinement in polarization-induced three-dimensional electron slabs: Importance of alloy scattering in AlGaN. Appl Phys Lett, 2006, 88: 042109 CrossRef ADS Google Scholar

[20] Simon J, Protasenko V, Lian C. Polarization-Induced Hole Doping in Wide-Band-Gap Uniaxial Semiconductor Heterostructures. Science, 2010, 327: 60-64 CrossRef PubMed ADS Google Scholar

[21] Li S, Ware M, Wu J. Polarization induced pn-junction without dopant in graded AlGaN coherently strained on GaN. Appl Phys Lett, 2012, 101: 122103 CrossRef ADS Google Scholar

[22] Fang Y L, Feng Z H, Yin J Y, et al. AlGaN/GaN polarization-doped field-effect transistors with graded heterostructure. IEEE Trans Electron Dev, 2014, 61: 4084--4089. Google Scholar

[23] Zhou X, Feng Z, Fang Y. Simulation study of GaN-based HFETs with graded AlGaN barrier. Solid-State Electron, 2015, 109: 90-94 CrossRef ADS Google Scholar

[24] Luo X R, Peng F, Yang C, et al. Polarization-doped enhancement mode HEMT. US Patent, US15/623371, 2017-6-14. Google Scholar

[25] Appels J A, Vaes H M J. High voltage thin layer device (RESURF devices). In: Proceedings of the International Electron Devices Meeting (IEDM), Washington, 1979. 238--241. Google Scholar

[26] Chen X B, Sin J K O. Optimization of the specific on-resistance of the COOLMOS. IEEE Trans Electron Dev, 2001, 48: 344--348. Google Scholar

[27] Zhang L, Ding K, Yan J C. Three-dimensional hole gas induced by polarization in (0001)-oriented metal-face III-nitride structure. Appl Phys Lett, 2010, 97: 062103 CrossRef ADS Google Scholar

[28] Li L, Yang L A, Cao R T, et al. Reduction of threading dislocations in N-polar GaN using a pseudomorphicaly grown graded-Al-fraction AlGaN interlayer. J Cryst Growth, 2013, 387: 1--5. Google Scholar

[29] Uren M J, Nash K J, Balmer R S. Punch-Through in Short-Channel AlGaN/GaN HFETs. IEEE Trans Electron Devices, 2006, 53: 395-398 CrossRef ADS Google Scholar

[30] Wei J, Jiang H, Jiang Q. Proposal of a GaN/SiC Hybrid Field-Effect Transistor for Power Switching Applications. IEEE Trans Electron Devices, 2016, 63: 2469-2473 CrossRef ADS Google Scholar

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