Optimum design for the ballistic diode based on graphene field-effect transistors

AbstractWe investigate the transport behavior of two-terminal graphene ballistic devices with bias voltages up to a few volts suitable for electronics applications. Four graphene devices based ballistic designs, specially fabricated from mechanically exfoliated graphene encapsulated by hexagonal boron nitride, exhibit strong nonlinear I-V characteristic curves at room temperature. A maximum asymmetry ratio of 1.58 is achieved at a current of 60 µA at room temperature through the ballistic behavior is limited by the thermal effect at higher bias. An analytical model using a specular reflection mechanism of particles is demonstrated to simulate the specular reflection of carriers from graphene edges in the ballistic regime. The overall trend of the asymmetry ratio depending on the geometry fits reasonably with the analytical model.

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Rectifying effect in high-performance ballistic diode bridge with a unique design for thermal energy harvesting

10.21203/rs.3.rs-514739/v1 ◽

2021 ◽

Author(s):

Dinh Cong Nguyen ◽

Minwook Kim ◽

Muhammad Hussain ◽

Van Huy Nguyen ◽

Yeon-jae Lee ◽

...

Keyword(s):

Thermal Energy ◽

High Performance ◽

Room Temperature ◽

Hexagonal Boron Nitride ◽

Electrical Energy ◽

Mean Free Path ◽

Thermal Excitation ◽

Ballistic Regime ◽

Johnson Noise ◽

Ballistic Diode

Abstract The long mean free path close to a micrometer in encapsulated graphene enabled us to rectify currents ballistically at room temperature. In this study, we introduce a ballistic rectifier that resembles a diode bridge and is based on graphene encapsulated using hexagonal boron nitride. Our device’s asymmetric geometry combined with the exploitation of the ratcheting effect means that it can operate successfully and provides excellent performance. The device’s estimated responsivities at 38,000 V/W for holes and 23,000 V/W for electrons at room temperature, are among the highest values for a ballistic device reported to date. Due to the device’s zero threshold voltage, it is able to rectify Johnson noise signals converting thermal excitation to electrical energy at room temperature. The bandwidth of the device at the ballistic regime is estimated at ~ 1.1 GHz for holes and 2 GHz for electrons. The device developed in this study is an important step along an innovative pathway that will lead to harvesting electrical energy directly from thermal energy.

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A novel analytical model for short channel heterostructure field effect transistors

Solid-State Electronics ◽

10.1016/s0038-1101(97)00291-8 ◽

1998 ◽

Vol 42 (4) ◽

pp. 605-612

Author(s):

Sang-Ho Song ◽

Dong Myong Kim

Keyword(s):

Analytical Model ◽

Field Effect ◽

Field Effect Transistors ◽

Short Channel ◽

Heterostructure Field Effect Transistors

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Evaluation of VTH and RON Drifts during Switch-Mode Operation in Packaged SiC MOSFETs

Electronics ◽

10.3390/electronics10040441 ◽

2021 ◽

Vol 10 (4) ◽

pp. 441

Author(s):

Marcello Cioni ◽

Alessandro Bertacchini ◽

Alessandro Mucci ◽

Nicolò Zagni ◽

Giovanni Verzellesi ◽

...

Keyword(s):

Field Effect Transistors ◽

Oxide Semiconductor ◽

Driving Voltage ◽

Drain Voltage ◽

Current Increase ◽

Mode Operation ◽

Switch Mode ◽

Gate Signal ◽

A Current ◽

Parameter Monitoring

In this paper, we investigate the evolution of threshold voltage (VTH) and on-resistance (RON) drifts in the silicon carbide (SiC) power metal-oxide-semiconductor field-effect transistors (MOSFETs) during the switch-mode operation. A novel measurement setup for performing the required on-the-fly characterization is presented and the experimental results, obtained on commercially available TO-247 packaged SiC devices, are reported. Measurements were performed for 1000 s, during which negative VTH shifts (i.e., VTH decrease) and negative RON drifts (i.e., RON decrease) were observed. To better understand the origin of these parameter drifts and their possible correlation, measurements were performed for different (i) gate-driving voltage (VGH) and (ii) off-state drain voltage (VPH). We found that VTH reduction leads to a current increase, thus yielding RON to decrease. This correlation was explained by the RON dependence on the overdrive voltage (VGS–VTH). We also found that gate-related effects dominate the parameter drifts at low VPH with no observable recovery, due to the repeated switching of the gate signal required for the parameter monitoring. Conversely, the drain-induced instabilities caused by high VPH are completely recoverable within 1000 s from the VPH removal. These results show that the measurement setup is able to discern the gate/drain contributions, clarifying the origin of the observed VTH and RON drifts.

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Polar Optical Phonon Instability and Intervalley Transfer in Gallium Nitride

MRS Proceedings ◽

10.1557/proc-512-549 ◽

1998 ◽

Vol 512 ◽

Cited By ~ 2

Author(s):

B. E. Foutz ◽

S. K. O'leary ◽

M. S. Shur ◽

L. F. Eastman ◽

B. L. Gelmont ◽

...

Keyword(s):

Gallium Nitride ◽

Analytical Model ◽

Optical Phonon ◽

Room Temperature ◽

Phonon Scattering ◽

Polar Optical Phonon ◽

Scattering Mechanism ◽

Loss Mechanism ◽

One Dimensional ◽

Optical Phonon Scattering

ABSTRACTWe develop a simple, one-dimensional, analytical model, which describes electron transport in gallium nitride. We focus on the polar optical phonon scattering mechanism, as this is the dominant energy loss mechanism at room temperature. Equating the power gained from the field with that lost through scattering, we demonstrate that beyond a critical electric field, 114 kV/cm at T = 300 K, the power gained from the field exceeds that lost due to polar optical phonon scattering. This polar optical phonon instability leads to a dramatic increase in the electron energy, this being responsible for the onset of intervalley transitions. The predictions of our analytical model are compared with those of Monte Carlo simulations, and are found to be in satisfactory agreement.

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Room temperature spin valve effect in the NiFe/Gr–hBN/Co magnetic tunnel junction

Journal of Materials Chemistry C ◽

10.1039/c6tc03425j ◽

2016 ◽

Vol 4 (37) ◽

pp. 8711-8715 ◽

Cited By ~ 22

Author(s):

Muhammad Zahir Iqbal ◽

Salma Siddique ◽

Ghulam Hussain ◽

Muhammad Waqas Iqbal

Keyword(s):

Boron Nitride ◽

Tunnel Junction ◽

Room Temperature ◽

Hexagonal Boron Nitride ◽

Spin Valve ◽

Magnetic Tunnel Junction ◽

Valve Effect ◽

First Time

Graphene and hexagonal boron nitride (hBN) have shown fascinating features in spintronics due to their metallic and tunneling behaviors, respectively. In this work, we report for the first time room temperature spin valve effect in NiFe/Gr–hBN/Co configuration.

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Room Temperature Band-Edge Luminescence from Silicon Grains Prepared by the Recrystallization of Mesoporous Silicon

MRS Proceedings ◽

10.1557/proc-452-517 ◽

1996 ◽

Vol 452 ◽

Author(s):

Karen L. Moore ◽

Leonid Tsybeskov ◽

Philippe M. Fauchet ◽

Dennis G. Hall

Keyword(s):

Room Temperature ◽

Silicon Oxide ◽

Crystalline Silicon ◽

Band Edge ◽

Applied Bias ◽

Mesoporous Silicon ◽

Room Temperature Photoluminescence ◽

Band Edge Luminescence ◽

A Current ◽

Better Than

AbstractRoom-temperature photoluminescence (PL) peaking at 1.1 eV has been found in electrochemically etched mesoporous silicon annealed at 950°C. Low-temperature PL spectra clearly show a fine structure related to phonon-assisted transitions in pure crystalline silicon (c-Si) and the absence of defect-related (e.g.P-line) and impurity-related (e.g.oxygen, boron) transitions. The maximum PL external quantum efficiency (EQE) is found to be better than 0.1% with a weak temperature dependence in the region from 12K to 400K. The PL intensity is a linear function of excitation intensity up to 100 W/cm2. The PL can be suppressed by an external electric field ≥ 105 V/cm. Room temperature electroluminescence (EL) related to the c-Si band-edge is also demonstrated under an applied bias ≤ 1.2 V and with a current density ≈ 20 mA/cm2. A model is proposed in which the radiative recombination originates from recrystallized Si grains within a non-stoichiometric Si-rich silicon oxide (SRSO) matrix.

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Critical Behavior in Au Nanoparticle Arrays: Implications for All-Metal Field Effect Transistors with Ultra-high Gain at Room Temperature

ACS Applied Nano Materials ◽

10.1021/acsanm.1c01641 ◽

2021 ◽

Author(s):

Abhijeet Prasad ◽

Michael Stoller ◽

Ravi F. Saraf

Keyword(s):

Critical Behavior ◽

Field Effect ◽

Room Temperature ◽

Field Effect Transistors ◽

High Gain ◽

Au Nanoparticle ◽

Nanoparticle Arrays

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The gamma-ray irradiation sensitivity and dosimetric information instability of RADFET dosimeter

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1304415p ◽

2013 ◽

Vol 28 (4) ◽

pp. 415-421 ◽

Cited By ~ 7

Author(s):

Milic Pejovic

Keyword(s):

Threshold Voltage ◽

Field Effect ◽

Room Temperature ◽

Gamma Ray ◽

Field Effect Transistors ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Threshold Voltage Shift ◽

Voltage Shift ◽

Gamma Ray Irradiation

The gamma-ray irradiation sensitivity to radiation dose range from 0.5 Gy to 5 Gy and post-irradiation annealing at room and elevated temperatures have been studied for p-channel metal-oxide-semiconductor field effect transistors (also known as radiation sensitive field effect transistors or pMOS dosimeters) with gate oxide thicknesses of 400 nm and 1 mm. The gate biases during the irradiation were 0 and 5 V and 5 V during the annealing. The radiation and the post-irradiation sensitivity were followed by measuring the threshold voltage shift, which was determined by using transfer characteristics in saturation and reader circuit characteristics. The dependence of threshold voltage shift DVT on absorbed radiation dose D and annealing time was assessed. The results show that there is a linear dependence between DVT and D during irradiation, so that the sensitivity can be defined as DVT/D for the investigated dose interval. The annealing of irradiated metal-oxide-semiconductor field effect transistors at different temperatures ranging from room temperature up to 150?C was performed to monitor the dosimetric information loss. The results indicated that the dosimeters information is saved up to 600 hours at room temperature, whereas the annealing at 150?C leads to the complete loss of dosimetric information in the same period of time. The mechanisms responsible for the threshold voltage shift during the irradiation and the later annealing have been discussed also.

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Effect of epitaxial alignment on electron transport from quasi-two-dimensional iron silicide alpha-FeSi-=SUB=-2-=/SUB=- nanocrystals into p-Si(001)

Физика и техника полупроводников ◽

10.21883/ftp.2018.05.45867.56 ◽

2018 ◽

Vol 52 (5) ◽

pp. 523

Author(s):

I.A. Tarasov ◽

M.V. Rautskii ◽

I.A. Yakovlev ◽

M.N. Volochaev

Keyword(s):

Electron Transport ◽

Room Temperature ◽

Molecular Beam ◽

Schottky Barrier Height ◽

Iron Silicide ◽

Current Voltage Characteristic ◽

Current Voltage ◽

Basic Orientation ◽

Different Temperatures ◽

A Current

AbstractSelf-assembled growth of α-FeSi_2 nanocrystal ensembles on gold-activated and gold-free Si(001) surface by molecular beam epitaxy is reported. The microstructure and basic orientation relationship (OR) between the silicide nanocrystals and silicon substrate were analysed. The study reveals that utilisation of the gold as catalyst regulates the preferable OR of the nanocrystals with silicon and their habitus. It is shown that electron transport from α-FeSi2 phase into p-Si(001) can be tuned by the formation of (001)—or (111)—textured α-FeSi2 nanocrystals ensembles. A current-voltage characteristic of the structures with different preferable epitaxial alignment (α-FeSi_2(001)/Si(100) and α-FeSi_2(111)/Si(100)) shows good linearity at room temperature. However, it becomes non-linear at different temperatures for different ORs due to different Schottky barrier height governed by a particular epitaxial alignment of the α-FeSi_2/ p -Si interfaces.

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