Advertisement

Nanoscale Research Letters

, 14:128 | Cite as

On the Baliga’s Figure-Of-Merits (BFOM) Enhancement of a Novel GaN Nano-Pillar Vertical Field Effect Transistor (FET) with 2DEG Channel and Patterned Substrate

  • Zeheng WangEmail author
  • Zirui Wang
  • Zhenwei Zhang
  • Di Yang
  • Yuanzhe YaoEmail author
Open Access
Nano Express
  • 445 Downloads

Abstract

A novel enhancement-mode vertical GaN field effect transistor (FET) with 2DEG for reducing the on-state resistance (RON) and substrate pattern (SP) for enhancing the breakdown voltage (BV) is proposed in this work. By deliberately designing the width and height of the SP, the high concentrated electric field (E-field) under p-GaN cap could be separated without dramatically impacting the RON, turning out an enhanced Baliga’s Figure-Of-Merits (BFOM, BV2/RON). Verified by experimentally calibrated ATLAS simulation, the proposed device with a 700-nm-long and 4.6-μm-width SP features six times higher BFOM in comparison to the FET without patterned substrate. Furthermore, the proposed pillar device and the SP inside just occupy a nano-scale area, enabling a high-density integration of such devices, which renders its high potential in future power applications.

Keywords

GaN FET Nano-pillar Patterned substrate 

Abbreviations

nA

Doping concentration of p-type GaN

nD

Doping concentration of n-type GaN

2DEG

Two-dimensional electron gas

Al0.23GaN

Aluminum gallium nitride with a mole fraction of 0.23 for aluminum

Al2O3

Aluminum oxide

BFOM

Baliga’s Figure-Of-Merits

DSP

Interface trap density of the substrate pattern

E-field

Electric field

ET

The difference between the conduction band and interface-trap energy-level

FET

Field effect transistor

GaN

Gallium nitride

HEMT

High electron mobility transistor

HG

Height of the gate

HW

Height of substrate pattern

LD

Length of the device

LG

Length of the Gate

LP

Length of the p-GaN cap

LW

Length of the substrate pattern

SiN

Silicon nitride

SP

Substrate pattern

SP-VFET

Vertical field effect transistor with substrate pattern

WD

Depth of the device

σp

Polarization charge

Background

Nowadays, wide bandgap semiconductors such as ZnO, In2O3, SiC, and gallium nitride (GaN) have attracted attention [1, 2, 3, 4, 5]. Whereas, considering the electronic properties, the lateral AlGaN/GaN high electron mobility transistor (HEMT) is widely considered as a potential candidate for substituting the Si-based device in power or frequency applications due to the higher breakdown voltage (BV) as well as the stronger thermal stability. A lot of efforts, such as p-type cap [6, 7], fluorine ion implantation [8, 9], thin barrier [10, 11], double channel [5, 12], and field-coupled gate [13], have been made on the realization of the enhancement-type HEMT that is desired to simplify the driver circuit.

These technologies face, however, many formidable challenges such as low uniformity of the threshold voltage, the waste of vertical chip area, current collapse, limited Baliga’s Figure-Of-Merits (BFOM), and so on. Especially, the contradiction between the drift length and the BV negatively influences the scaling-down of the device [14, 15]. In other words, smaller device leads to lower BV, in which it is harder to adopt the junction terminals that promote the BFOM by optimizing the electric field distribution. To this end, back barrier [16], buried junction [17], quantum well field plate [18], and other structures that are inserted into the lateral HEMT exhibiting the feature of the electrical field plate have been proposed to enhance BV by utilizing the vertical region of the chip.

On the other hand, by the virtue of the superior natures of GaN, the bulk GaN vertical field effect transistor (VFET) attracts more and more attention due to the easier realization of enhancement-type functionality and the full utilization of the vertical region [19, 20, 21, 22]. Many novel structures are presented by experiments or simulations to incline the BV and simultaneously reduce the on-state resistance (RON) [23, 24, 25]. However, not to mention the difficulties in fabricating the super-junction (SJ) in GaN, the lack of the high-mobility two-dimensional electron gas (2DEG) leads to a higher RON [26], which hinders the optimization of BFOM in such devices.

In this work, a novel enhancement-mode vertical GaN FET with 2DEG for reducing the RON and substrate pattern (SP) for enhancing the BV is proposed, wherein the combination of the 2DEG channel and the SP effectively balances the contradiction between the low on-state resistance and the high BV. Furthermore, the proposed device pillar and the SP inside just occupy a nano-scale area, enabling a high-density integration of such devices. Verified by numerical simulation constructed in ATLAS, the proposed device features higher BFOM compared with the same field effect transistor (FET) without the patterned substrate, rendering its high potential in future power applications.

Method

The proposed device is generated in a normal Al0.23GaN/GaN wafer with a highly concentrated n-type substrate acting as the drain electrode as shown in Fig. 1a, where the thickness of the layer silicon nitride (SiN), AlGaN, and GaN are 105 nm, 20 nm, and 5 μm, respectively. A n-type GaN with 2 × 1016 cm−3 doping nD and a p-type GaN cap with 2 × 1017 cm−3 doping nA is set as the buffer and the composite channel respectively [27, 28]. Another component of the channel beside the gate is a thin AlGaN layer which is introduced for inducing 2DEG as shown in Fig. 1b. A SP, made by aluminum oxide (Al2O3) for example in this paper, is grown on the substrate.
Fig. 1

The schematic a 3D pillar structure and b cross-section with labeled geometric parameters of the proposed SP-VFET

The whole device therefore could be fabricated by a standard process successively: (1) the epitaxial deposition of the conduction substrate and the integrate SP layer, (2) the partial etching of the SP pattern, (3) the deposition and polishing of n-GaN buffer, (4) the deposition of AlGaN barrier and p-GaN cap, and (5) the fabrication of electrodes and passivation.

The implanted ATLAS simulator is calibrated by the experimental data from an enhancement-type HEMT with a p-GaN cap [29, 30]. The calibrated and other specifications of the device are shown in Table 1. Other configurations could be found in our previous work [31]. Type and density of the interface trap located at the SP/GaN interface are referred to capacitance-based experimental measurements [32, 33, 34]. The polarization charge on the AlGaN/GaN surface is confirmed according to the corresponding simple quadratic fitting equation [35].
Table 1

Device specifications

Parameter

Value and unit

Device length

LD = 1 μm

Device depth

WD = 1 μm

Polarization charge

σp= 6.5 × 1012 cm−2

SP interface trap (Al2O3)

DSP = 8 × 1012 cm−2; ET = EC-0.5 eV

p-GaN cap length

LP = 0.4 to 0.7 μm

SP length

LW = 0 to 800 nm

SP height

HW = 0 to 4.7 μm

Gate length

LG = 15 nm

Gate height

LW = 0.17 μm

Physics Mechanism

In on-state, compared with the device without the 2-DEG channel and the SP, the proposed vertical field effect transistor with substrate pattern (SP-VFET) features a highly conductive path owing to the 2-DEG and a narrower vertical current channel that shrinks the conductance as shown in Fig. 2. In detail, thanks to the high-density 2DEG concentrated at the AlGaN/GaN interface, the lateral path of the current flow could be sustained, which partially compensates the whole device conductance. In contrast, the current transportation capability of the SP-VFET device without 2DEG channel would be influenced dramatically.
Fig. 2

The schematic illustration of the forward current flow in a the device without the SP, b the proposed SP-VFET with a short SP, and c a long SP

The length of the p-GaN cap would not dramatically influence the concentration of electric field (E-field) until the length is longer than 700 nm by which the p-GaN almost covers the whole device surface. As shown in Fig. 3, the E-field distribution along the AlGaN/GaN interface owns a peak around the right corner of the p-GaN. The position of the peak shifts along with the varying p-GaN length, and however, keeps the same magnitude. Tiny difference of the peak value could be seen in Fig. 3 when the p-GaN cap is longer than 600 nm, because the long p-GaN cap flattens the whole E-field in the device and hereby expands the resistance of the device due to the depletion of the 2DEG.
Fig. 3

The electric field distribution of the device without the SP along the AlGaN/GaN heterojunction in different p-GaN length

To illustrate the influence of the simultaneously introduced p-GaN, 2-DEG, and the SP, an on-state conduction model can be built, as schematically shown in Fig. 4a. M1 and M2 are the MIS-like transistors with the conduct-channel formed in p-GaN and AlGaN respectively. R1 represents the infinitesimal part of vertical resistance in bulk GaN. R2 and R3 represent the infinitesimal resistance parts of 2-DEG channel with and without being partly depleted respectively. According to the law of resistance, R1, R2, and R3 can be obtained as
$$ {R}_1=\frac{1}{n_1 q\mu}\bullet \frac{l}{dx\bullet {W}_D} $$
$$ {R}_2=\frac{1}{n_2 q\mu}\bullet \frac{dx}{t\bullet {W}_D} $$
$$ {R}_3=\frac{1}{n_3 q\mu}\bullet \frac{dx}{t\bullet {W}_D} $$
where n1, n2, and n3 represent the electric concentration in GaN, undepleted 2-DEG, and depleted 2-DEG respectively; q is the electron charge and μ is the mobility of electron in GaN; l is the length of vertical conductive path and dx is the infinitesimal length in horizon; WD is the width of the device; and t is the thickness of the 2-DEG. For convenience, t is set to be 10 nm [7]. The concentration of the depleted 2-DEG under p-GaN n3 equals the undepleted concentration n1 minus the total negative charge in the depleted p-GaN [31], which reads
$$ {n}_3={n}_2-{n}_A{x}_D $$
Fig. 4

The schematic of a proposed on-state model without SP b on-state resistance network model with SP

The p-GaN cap can be regarded as fully depleted, thus xD equals 105 nm, the thickness of p-GaN. Compared with R1, R2 and R3 are much lower than R1, because of their higher electron concentration and shorter conductive path. Therefore, the resistance in the 2-DEG channel can be ignored. In addition, when the drain voltage is small and the MIS-like transistors M1 and M2 work in the unsaturated model, the on-state resistance of M1 and M2 can be regarded as an ignorable constant resistance Rn. To simplify the calculation, the analytical form of vertical current path conductance Gv of vertical current path can be obtained as
$$ {G}_v={\int}_0^{L_D}\frac{1}{R_1}={\int}_0^{L_D}{n}_1 q\mu \bullet \frac{dx\bullet {W}_D}{l} $$
where LD is the length of the device.
Therefore, the on-state resistance Ron can be obtained, which reads
$$ {R}_{on}=\frac{1}{G_v}+{R}_n=\frac{1}{n_1 q\mu}\bullet \frac{l}{L_D\bullet {W}_D}+{R}_n $$
When SP exists, as shown in Fig. 4b, the vertical conductive path has been blocked partially. Thus, the conductance of vertical current path can be expressed as
$$ {G}_v={\int}_{L_W}^{L_{\mathrm{D}}}\frac{1}{R_1}={\int}_{L_W}^{L_D}{n}_1 q\mu \bullet \frac{dx\bullet {W}_D}{l} $$
where LW is the length of the SP.
Therefore, the corresponding Ron can be expressed as
$$ {R}_{on}=\frac{1}{G_v}+{R}_n=\frac{1}{n_1 q\mu}\bullet \frac{l}{\left({L}_D-{L}_W\right)\bullet {W}_D}+{R}_n $$
In off-state, due to the capacitor-like functionality and the negatively charged interface trap, the SP would redistribute the electric field under the p-GaN cap effectively, turning out a field concentration around the SP that owns wider band gap as shown in Fig. 5. Such E-field redistribution shrinks the depletion region that appears around p-GaN and the gate, and thereby relieves the high field concentration around the p-GaN cap and the gate, which would enhance the BV of the SP-VFET remarkably. On the other hand, as mentioned above, the SP would influence the device conductance such that the negative charge introduced by the SP leads to the increase of potential energy near the gate, which accounts for the decrease of 2-DEG near the gate. As a result, a fluctuant BFOM would be achieved with varying the length and the height of the SP.
Fig. 5

The schematic distribution of the electric field and depletion region in a the device without the SP, b the proposed SP-VFET with a short SP, and c the proposed SP-VFET with a long SP

In other words, the SP could reduce the peak of the E-field around the p-GaN corner and simultaneously, attract the E-field concentrating across the SP, as shown in Fig. 6a, b. However, thanks to the higher critical E-field of the SP, such E-field concentration would not break the device, by which the SP-VFET would exhibit much higher BV.
Fig. 6

The electric field distribution of the proposed SP-VFET along the interface of a p-GaN/AlGaN and b GaN/SP

Result and Discussion

Figure 7a, b respectively shows the transfer and output curves of the proposed device without the SP. With different length of the p-GaN cap, these curves overlay each other in both subthreshold and turn-on regimes, suggesting the length of the p-GaN cap does not influence the conductance of the device without the SP. In other words, although the p-GaN cap would partially deplete the 2-DEG and hereby affect the resistance of the 2-DEG channel, the remained 2-DEG still owns a large concentration n3 that approximates the undepleted concentration n2, which is realized by optimizing the p-type concentration in p-GaN cap. Furthermore, as analyzed before, the resistance of the 2-DEG channel is rather small compared with the resistance of the n-GaN in vertical path. Therefore, the transfer curves overlay each other in Fig. 7a, b. However, in order to protect the gate from the highly concentrated E-field, such crowding should not be adjacent to the gate, which means the length of the p-GaN could not be too short. Thus, the minimum length of the p-GaN in our work is 400 nm unless otherwise stated.
Fig. 7

a The transfer curves and b output curves of the device without the SP in different length of the p-GaN cap

Figure 8 shows the output characteristics of the proposed SP-VFET and the VFET without the SP. It can be seen that the SP does impose the device resistance by narrowing the vertical conduction channel. In detail, the on-state resistance is independent to the height of the SP when the height is below 4.7 μm, while, significantly depends on the length of the SP which matches the mechanism that narrow vertical current path shrinks the conductance. The former independency is because the 2DEG is the main lateral conduction channel that would not be weakened by the SP within its moderate height. However, if the SP is adjacent to 2-DEG channel, the introduced negative charge around the SP will level up the energy band, resulting in the dramatical decrease of the 2-DEG concentration. Consequently, the resistance of the 2-DEG increases and the total on-state resistance Ron increases accordingly. Besides, the later dependency comes from the remarkably boosted resistance in the vertical channel as aforementioned. Furthermore, it should be noted that the lattice defects in 2-DEG induced by high SP limit the height of SP.
Fig. 8

The output curves of the proposed SP-VFET with varying a SP width and b SP length compared with the device without SP

Figure 9 shows the details of the current density distribution around the gate of the VFET devices with or without the SP, wherein the VFET without the SP has a higher current transportation capability which keeps in line with Fig. 8a. And oppositely, the SP-VFET shrinks the current conduction by narrowing the vertical channel. Meanwhile, the detailed figures clearly illustrate that the current in the lateral channel is transported by the 2DEG, and the total current density changes slightly with growing SP height, which is also demonstrated in the mechanism section. The results indicate the lateral channel resistance is not imposed notably by the SP within moderate height.
Fig. 9

The current density of a the device without the SP and bd the proposed SP-VFET with different SP geometric parameters

Figure 10a shows the extracted on-state resistance and the corresponding BV. The resistance of the SP-VFET increases with longer SP. And especially, the curve of the resistance versus SP length exhibits a hyperbolic trend, and the gradient of the curve increases with the longer SP length. As analyzed before, Ron varies with different SP length LW in a form of hyperbolic function, which matches the simulation result. Moreover, the curve of the resistance with different SP heights overlays each other as the height is lower than 4.7 μm, suggesting that 2-DEG channel is the main lateral conductive path and the 2-DEG channel is not affected, as mentioned above.
Fig. 10

a The extracted on-state resistance as well as BV, and b the according BFOM of the proposed SP-VFET in different SP length and width

Figure 10b shows the calculated BFOM of the SP-VFET. Owing to the different increasing rate of BV and on-state resistance, the BFOM of all the devices firstly grow and then drop after the length of the SP longer than 400 nm. A peak BFOM of 125 MW/cm2 is achieved when the length reaches 700 nm and the height reaches 4.6 μm. Compared with the device without the SP, the proposed SP-VFET performs more than six times better in terms of the BFOM.

This improvement is achieved owning to the suppression of the high E-field under the p-GaN, thanks to the negatively charged interface trap around the SP. The interaction, which occurs between the trapped negative charge on the interface of the SP and the depletion region around the p-GaN, forms a new distribution of E-field mainly towards the trapped charge. According to the Gauss’ law, the electric flux is limited by the charge encircled. Thus, the introduced E-field will affect the electric flux toward elsewhere. As the negative charge of depletion region is the main source for the crowed E-field around p-GaN, the E-field introduced by the trapped charge will play a role in suppressing the E-field crowed around p-GaN, and consequently, BV is enhanced. Specifically, when the SP length is lower than 400 nm, the negative charge introduced by SP is far away from the depletion region. Thus, the E-field formed between the depletion region and trapped negative charge is too small to play a role in affecting the crowed E-field under p-GaN. And as a result, the BV of the device grows slightly. However, as the SP length is higher than 400 nm, owing to the more trapped negative charge on the interface of the SP and shorter distance between the depletion region and trapped negative charge, the E-field between the depletion region and trapped negative charge is enhanced, leading to the growth of the BV.

Additionally, the region around the SP is tremendously depleted due to the negative charge introduced by SP. And as shown in Fig. 11, with the longer SP, the vertical leakage current path constricts in width owing to the depleted region squeezing to the device edge, which also block the leakage current, and consequently enhance the BV. Therefore, the BV rises remarkably with the increasing SP length.
Fig. 11

The leakage current density of a the device without the SP and bd the proposed SP-VFET with different SP geometric parameters

Figure 12 shows the simulated E-field distribution in the SP-VFET when the drain voltage is 300 V, where apparently the SP induces other new E-field concentration points, meaning that the peak E-field region under the p-GaN is suppressed. Compared with the E-field distribution in the devices with different SP height, the increase of SP length suppresses the congregation of E-field and consequently enhances the BV more efficiently.
Fig. 12

The E-field distribution around the gate of the VFET a with or bd without the SP when the drain voltage is 300 V

Such flattened E-field could also be observed explicitly in Fig. 13, in which the E-field distributions along the horizontal and perpendicular edge of the SP (see the cutline) are plotted. As demonstrated in polychrome Fig. 12, it can be seen in Fig. 13 that higher and longer SP plays a more and more effective role in reconstructing the E-field under p-GaN, and, attracting E-field to concentrate across the SP edge. This redistribution counteracts the E-field around vulnerable p-GaN. Thus, the BV of the device is enhanced, boosting the B-FOM of proposed SP-VFET.
Fig. 13

The E-field distribution a horizontally and b perpendicularly extracted along the cutline of the SP edge in the SP-VFET

Conclusion

In this work, a novel enhancement-type GaN vertical FET (SP-VFET) with 2DEG channel and substrate pattern for improving the BFOM thereof is proposed and investigated. Verified by experimentally calibrated simulation implemented with ATLAS, it is the SP that relieves the E-field peak under the p-GaN, and simultaneously, attracts new E-field concentration across the SP that owns higher critical E-field. Consequently, the BV of the proposed SP-VFET is boosted with a moderately increasing on-state resistance due to the 2DEG compensation. The BFOM of the SP-VFET therefore is enhanced six times better than that of the device without the SP when the SP length and height are 700 nm and 4.6 μm respectively, rendering the promising potential of the proposed SP-VFET in high-density power integration.

Notes

Acknowledgements

All the authors are associated under the Undergraduate Training Program for Innovation and Entrepreneurship (No. 201810614067) with University of Electronic Science and Technology of China (UESTC).

Funding

This work was supported by Sichuan Science and Technology Program under Grant 2019YFH0006.

Availability of Data and Materials

The date generated during and/or analyzed during the current study are available from the corresponding authors on reasonable request.

Authors’ Contributions

ZW brought out the idea of the structure and supervised the simulation. ZW and ZZ carried out the simulations and analysis. DY created the figures and wrote the manuscript. YY supervised the whole work. All authors discussed the results and contributed to the final manuscript. All the authors have read and approved the final manuscript.

Competing Interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

References

  1. 1.
    Wang F, Song L, Zhang H et al (2018) ZnO nanofiber thin-film transistors with low-operating voltages. Adv Electron Mater 4:1700336  https://doi.org/10.1002/aelm.201700336 CrossRefGoogle Scholar
  2. 2.
    Zhang H, Meng Y, Song L et al (2018) High-performance enhancement-mode thin-film transistors based on Mg-doped In2O3nanofiber networks. Nano Res 11:1227–1237  https://doi.org/10.1007/s12274-017-1735-8 CrossRefGoogle Scholar
  3. 3.
    Song L, Luo L, Li X et al (2019) Modulating electrical performances of In2O3 nanofiber channel thin film transistors via Sr doping. Adv Electron Mater 5:1800707  https://doi.org/10.1002/aelm.201800707 CrossRefGoogle Scholar
  4. 4.
    Wei J, Zhang M, Jiang H et al (2016) Low ON-resistance SiC trench/planar MOSFET with reduced OFF-state oxide field and low gate charges. IEEE Electron Device Lett 37:1458–1461  https://doi.org/10.1109/LED.2016.2609599 CrossRefGoogle Scholar
  5. 5.
    Wei J, Zhang M, Li B et al (2018) An analytical investigation on the charge distribution and gate control in the normally-off GaN double-channel MOS-HEMT. IEEE Trans Electron Devices 65:2757–2764  https://doi.org/10.1109/TED.2018.2831246 CrossRefGoogle Scholar
  6. 6.
    Hao R, Li W, Fu K et al (2017) Breakdown enhancement and current collapse suppression by high-resistivity GaN cap layer in normally-off AlGaN/GaN HEMTs. IEEE Electron Device Lett 38:1567–1570  https://doi.org/10.1109/LED.2017.2749678 CrossRefGoogle Scholar
  7. 7.
    Su LY, Lee F, Huang JJ (2014) Enhancement-mode GaN-based high-electron mobility transistors on the Si substrate with a p-type GaN cap layer. IEEE Trans Electron Devices 61:460–465  https://doi.org/10.1109/TED.2013.2294337 CrossRefGoogle Scholar
  8. 8.
    Cai Y, Zhou Y, Chen KJ, Lau KM (2005) Self-aligned enhancement-mode AlGaN/GaN HEMTs using fluoride-based plasma treatment. Device Res Conf - Conf Dig DRC 2005:179–180  https://doi.org/10.1109/DRC.2005.1553110 Google Scholar
  9. 9.
    Cai Y, Zhou Y, Lau KM, Chen KJ (2006) Control of threshold voltage of AlGaN/GaN HEMTs by fluoride-based plasma treatment: from depletion mode to enhancement mode. IEEE Trans Electron Devices 53:2207–2214  https://doi.org/10.1109/TED.2006.881054 CrossRefGoogle Scholar
  10. 10.
    Huang S, Liu X, Wang X et al (2018) Ultrathin-barrier AlGaN/GaN heterostructure: a recess-free technology for manufacturing high-performance GaN-on-Si power devices. IEEE Trans Electron Devices 65:207–214  https://doi.org/10.1109/TED.2017.2773201 CrossRefGoogle Scholar
  11. 11.
    Huang S, Liu X, Wang X et al (2016) High uniformity normally-OFF GaN MIS-HEMTs fabricated on ultra-thin-barrier AlGaN/GaN heterostructure. IEEE Electron Device Lett 37:1617–1620  https://doi.org/10.1109/LED.2016.2617381 CrossRefGoogle Scholar
  12. 12.
    Wei J, Liu S, Li B et al (2015) Low on-resistance normally-off GaN double-channel metal-oxide-semiconductor high-electron-mobility transistor. IEEE Electron Device Lett 36:1287–1290  https://doi.org/10.1109/LED.2015.2489228 CrossRefGoogle Scholar
  13. 13.
    Wang Z, Cao J, Wang F et al (2018) Proposal of a novel enhancement type AlGaN/GaN HEMT using recess-free field coupled gate. Superlattice Microst 122:343–348  https://doi.org/10.1016/j.spmi.2018.07.016 CrossRefGoogle Scholar
  14. 14.
    Zhou C, Chen W, Piner EL, Chen KJ (2010) AlGaN/GaN dual-channel lateral field-effect rectifier with punch through breakdown immunity and low on-resistance. IEEE Electron Device Lett 31:5–7  https://doi.org/10.1109/LED.2009.2034761 CrossRefGoogle Scholar
  15. 15.
    Si J, Wei J, Chen W, Zhang B (2013) Electric field distribution around drain-side gate edge in algan/gan hemts: analytical approach. IEEE Trans Electron Devices 60:3223–3229  https://doi.org/10.1109/TED.2013.2272055 CrossRefGoogle Scholar
  16. 16.
    Lee HS, Piedra D, Sun M et al (2012) 3000-V 4.3-mΩ ċ cm2InAlN/GaN MOSHEMTs with AlGaN back barrier. IEEE Electron Device Lett 33:982–984  https://doi.org/10.1109/LED.2012.2196673 CrossRefGoogle Scholar
  17. 17.
    Wang Z, Wang F, Guo S, Wang Z (2017) Simulation study of high-reverse blocking AlGaN/GaN power rectifier with an integrated lateral composite buffer diode. Micro Nano Lett 12:660–663  https://doi.org/10.1049/mnl.2017.0057 CrossRefGoogle Scholar
  18. 18.
    Wang Z, Cao J, Sun R et al (2018) Numerical investigation on AlGaN/GaN short channel HEMT with AlGaN/InGaN/AlGaN quantum well plate. Superlattice Microst 120:753–758  https://doi.org/10.1016/j.spmi.2018.06.045 CrossRefGoogle Scholar
  19. 19.
    Otake H, Chikamatsu K, Yamaguchi A et al (2008) Vertical GaN-based trench gate metal oxide semiconductor field-effect transistors on GaN bulk substrates. Appl Phys Express 1:2–4  https://doi.org/10.1143/APEX.1.011105 CrossRefGoogle Scholar
  20. 20.
    Nie H, Diduck Q, Alvarez B et al (2014) 1.5-kV and 2.2-mω-cm2vertical gan transistors on Bulk-GaN substrates. IEEE Electron Device Lett 35:939–941  https://doi.org/10.1109/LED.2014.2339197 CrossRefGoogle Scholar
  21. 21.
    Sun M, Zhang Y, Gao X, Palacios T (2017) High-performance GaN vertical fin power transistors on bulk GaN substrates. IEEE Electron Device Lett 38:509–512  https://doi.org/10.1109/LED.2017.2670925 CrossRefGoogle Scholar
  22. 22.
    Ji D, Gupta C, Agarwal A et al (2018) Large-area in-situ oxide, GaN interlayer-based vertical trench MOSFET (OG-FET). IEEE Electron Device Lett 39:711–714  https://doi.org/10.1109/LED.2018.2813312 CrossRefGoogle Scholar
  23. 23.
    Ji D, Li W, Agarwal A et al (2018) Improved dynamic RON of GaN vertical trench MOSFETs (OG-FETs) using TMAH wet etch. IEEE Electron Device Lett 39:1030–1031  https://doi.org/10.1109/LED.2018.2843335 CrossRefGoogle Scholar
  24. 24.
    Oka T, Ina T, Ueno Y, Nishii J (2015) 1.8mΩ·cm2 vertical GaN-based trench metal-oxide-semiconductor field-effect transistors on a free-standing GaN substrate for 1.2-kV-class operation. Appl Phys Express 8:2–4  https://doi.org/10.7567/APEX.8.054101 CrossRefGoogle Scholar
  25. 25.
    Hemt EVS, Li Z, Member S, Chow TP (2013) Design and simulation of 5–20-kV GaN. IEEE Trans Electron Devices 60:3230–3237CrossRefGoogle Scholar
  26. 26.
    Chowdhury S, Mishra UK (2013) Lateral and vertical transistors using the Algan/GAN Heterostructure. IEEE Trans Electron Devices 60:3060–3066  https://doi.org/10.1109/TED.2013.2277893 CrossRefGoogle Scholar
  27. 27.
    Hao R, Wu D, Fu K et al (2018) 10 A/567 V normally off p-GaN gate HEMT with high-threshold voltage and low-gate leakage current. Electron Lett 54:848–849  https://doi.org/10.1049/el.2017.3981 CrossRefGoogle Scholar
  28. 28.
    Oka T, Ueno Y, Ina T, Hasegawa K (2014) Vertical GaN-based trench metal oxide semiconductor field-effect transistors on a free-standing GaN substrate with blocking voltage of 1.6 kV. Appl Phys Express 7:021002  https://doi.org/10.7567/APEX.7.021002 CrossRefGoogle Scholar
  29. 29.
    Hilt O, Brunner F, Cho E et al (2011) Normally-off high-voltage p-GaN gate GaN HFET with carbon-doped buffer. Proc Int Symp Power Semicond Devices ICs:239–242  https://doi.org/10.1109/ISPSD.2011.5890835
  30. 30.
    Hilt O, Würfl J, Kuzmík J (2016) Gate reliability investigation in normally-off. IEEE Electron Device Lett 37:385–388  https://doi.org/10.1109/LED.2016.2535133 CrossRefGoogle Scholar
  31. 31.
    Wang Z, Wang S, Zhang Z et al (2019) A high-performance tunable LED-compatible current regulator using an integrated voltage nanosensor. IEEE Trans Electron Devices PP:1–7  https://doi.org/10.1109/TED.2019.2899756 CrossRefGoogle Scholar
  32. 32.
    Ťapajna M, Kuzmík J, Čičo K et al (2009) Interface states and trapping effects in Al2O3- and ZrO2/InAlN/AlN/GaN metal-oxide-semiconductor heterostructures. Jpn J Appl Phys 48:0902011–0902013  https://doi.org/10.1143/JJAP.48.090201 CrossRefGoogle Scholar
  33. 33.
    Long RD, Jackson CM, Yang J et al (2013) Interface trap evaluation of Pd/Al2O3/GaN metal oxide semiconductor capacitors and the influence of near-interface hydrogen. Appl Phys Lett 103:2–7  https://doi.org/10.1063/1.4827102 Google Scholar
  34. 34.
    Ťapajna M, Jurkovič M, Válik L et al (2013) Bulk and interface trapping in the gate dielectric of GaN based metal-oxide-semiconductor high-electron-mobility transistors. Appl Phys Lett 102:1–5  https://doi.org/10.1063/1.4811754 CrossRefGoogle Scholar
  35. 35.
    Ambacher O, Majewski J, Miskys C et al (2002) Pyroelectric properties of Al(In)GaN/GaN hetero- and quantum well structures. J Phys Condens Matter 14:3399–3434  https://doi.org/10.1088/0953-8984/14/13/302 CrossRefGoogle Scholar

Copyright information

© The Author(s). 2019

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  1. 1.School of Information and Software EngineeringUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China
  2. 2.School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengduPeople’s Republic of China

Personalised recommendations