Analysis of Gate Oxide Nitridation Effect on SiC MOSFETs by Using Hall Measurement and Split C–V Measurement

In this study, 4H–SiC inversion layers were experimentally evaluated by Hall and split C–V measurements, and scattering mechanisms related to gate oxide nitridation were analyzed. Three typical samples with different crystal plane directions and gate oxidation conditions were prepared, and their total trap density and Hall mobility were compared. Based on the temperature dependence of the Hall mobility, we found that scattering mechanisms differed for each sample. The sample C-face oxynitride which had a high nitrogen density at the metal–oxide–semiconductor (MOS) interface, showed a similar temperature dependency to that of ionized impurity scattering. This result suggests that high-density nitrogen acts as donors that supply free carriers and cause ionized impurity scattering, just like in a bulk crystal. In addition, the sample C-face wet has lowest influence of the Coulomb scattering because of the lowest temperature dependence of Hall mobility and the lowest total trap density.

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Simulation of the Impact of Ionized Impurity Scattering on the Total Mobility in Si Nanowire Transistors

Materials ◽

10.3390/ma12010124 ◽

2019 ◽

Vol 12 (1) ◽

pp. 124 ◽

Cited By ~ 13

Author(s):

Toufik Sadi ◽

Cristina Medina-Bailon ◽

Mihail Nedjalkov ◽

Jaehyun Lee ◽

Oves Badami ◽

...

Keyword(s):

Surface Roughness ◽

Small Diameter ◽

Golden Rule ◽

Impurity Scattering ◽

Boltzmann Transport ◽

Nanowire Transistors ◽

Scattering Mechanisms ◽

Relaxation Time Approximation ◽

Ionized Impurity Scattering ◽

The Impact

Nanowire transistors (NWTs) are being considered as possible candidates for replacing FinFETs, especially for CMOS scaling beyond the 5-nm node, due to their better electrostatic integrity. Hence, there is an urgent need to develop reliable simulation methods to provide deeper insight into NWTs’ physics and operation, and unlock the devices’ technological potential. One simulation approach that delivers reliable mobility values at low-field near-equilibrium conditions is the combination of the quantum confinement effects with the semi-classical Boltzmann transport equation, solved within the relaxation time approximation adopting the Kubo–Greenwood (KG) formalism, as implemented in this work. We consider the most relevant scattering mechanisms governing intraband and multi-subband transitions in NWTs, including phonon, surface roughness and ionized impurity scattering, whose rates have been calculated directly from the Fermi’s Golden rule. In this paper, we couple multi-slice Poisson–Schrödinger solutions to the KG method to analyze the impact of various scattering mechanisms on the mobility of small diameter nanowire transistors. As demonstrated here, phonon and surface roughness scattering are strong mobility-limiting mechanisms in NWTs. However, scattering from ionized impurities has proved to be another important mobility-limiting mechanism, being mandatory for inclusion when simulating realistic and doped nanostructures, due to the short range Coulomb interaction with the carriers. We also illustrate the impact of the nanowire geometry, highlighting the advantage of using circular over square cross section shapes.

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Electrical Characterization of GaN Metal Oxide Semiconductor Diode using Sc2O3 as the Gate Oxide

MRS Proceedings ◽

10.1557/proc-693-i11.47.1 ◽

2001 ◽

Vol 693 ◽

Cited By ~ 2

Author(s):

R. Mehandru ◽

B.P. Gila ◽

J. Kim ◽

J.W. Johnson ◽

K.P. Lee ◽

...

Keyword(s):

Metal Oxide ◽

Inductively Coupled Plasma ◽

Electron Cyclotron Resonance ◽

Gate Oxide ◽

Metal Oxide Semiconductor ◽

Trap Density ◽

Oxide Semiconductor ◽

Semiconductor Diode ◽

Interface Trap Density ◽

Interface Trap

AbstractGaN metal oxide semiconductor diodes were demonstrated utilizing Sc2O3 as the gate oxide. Sc2O3 was grown at 100°C on MOCVD grown n-GaN layers in a molecular beam epitaxy (MBE) system, using a scandium elemental source and an Electron Cyclotron Resonance (ECR) oxygen plasma. Ar/Cl2 based discharges was used to remove Sc2O3, in order to expose the underlying n-GaN for ohmic metal deposition in an Inductively Coupled Plasma system. Electron beam deposited Ti/Al/Pt/Au and Pt/Au were utilized as ohmic and gate metallizations, respectively. An interface trap density of 5 × 1011 eV-1cm-2was obtained with the Terman method. Conductance-voltage measurements were also used to estimate the interface trap density and a slightly higher number was obtained as compared to the Terman method. Results of capacitance measurements at elevated temperature (up to 300°C) indicated the presence of deep states near the interface.

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Electron scattering mechanisms in indium-tin-oxide thin films: grain boundary and ionized impurity scattering

Vacuum ◽

10.1016/j.vacuum.2004.03.008 ◽

2004 ◽

Vol 75 (3) ◽

pp. 275-282 ◽

Cited By ~ 76

Author(s):

Ho-Chul Lee ◽

O Ok Park

Keyword(s):

Thin Films ◽

Grain Boundary ◽

Electron Scattering ◽

Tin Oxide ◽

Indium Tin Oxide ◽

Impurity Scattering ◽

Oxide Thin Films ◽

Scattering Mechanisms ◽

Ionized Impurity Scattering

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Scattering Probabilities for Holes I. Deformation Potential and Ionized Impurity Scattering Mechanisms

physica status solidi (b) ◽

10.1002/pssb.2220580206 ◽

1973 ◽

Vol 58 (2) ◽

pp. 471-482 ◽

Cited By ~ 89

Author(s):

M. Costato ◽

L. Reggiani

Keyword(s):

Impurity Scattering ◽

Deformation Potential ◽

Scattering Mechanisms ◽

Ionized Impurity Scattering

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LOW-FIELD ELECTRON TRANSPORT PROPERTIES IN ZINCBLENDE AND WURTZITE GaN STRUCTURES USING AN ITERATION MODEL FOR SOLVING BOLTZMANN EQUATION

Modern Physics Letters B ◽

10.1142/s021798490901948x ◽

2009 ◽

Vol 23 (10) ◽

pp. 1359-1366 ◽

Cited By ~ 1

Author(s):

H. ARABSHAHI ◽

A. A. MOWLAVI

Keyword(s):

Electron Transport ◽

Transport Properties ◽

Impurity Scattering ◽

Free Carriers ◽

Low Field ◽

Ionized Impurity Scattering ◽

Iteration Model ◽

Electron Transport Properties ◽

Gan Crystal ◽

Electron Drift Mobility

An iteration calculation has been carried out to study electron transport properties in zincblende and wurtzite GaN materials. The two-mode nature of the polar optic phonons is considered jointly with deformation potential acoustic, piezoelectric, ionized impurity scattering. Band non-parabolicity, admixture of p functions, arbitrary degeneracy of the electron distribution, and the screening effects of free carriers on the scattering probabilities are incorporated. Electron drift mobility in both zincblende and wurtzite GaN crystal structures are calculated for different temperature and doping dependencies. It is found that the electron mobility decreases monotonically as the temperature increases from 100 K to 600 K. The low temperature value of electron mobilty increases significantly with increasing doping concentration. The agreement of iterative results with the available experimental data is found to be satisfactory.

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Electrical Characterization of GaN Metal Oxide Semiconductor Diodes Using MgO as the Gate Oxide

MRS Proceedings ◽

10.1557/proc-693-i11.30.1 ◽

2001 ◽

Vol 693 ◽

Author(s):

J. Kim ◽

B. P. Gila ◽

R. Mehandru ◽

J.W. Johnson ◽

J. H. Shin ◽

...

Keyword(s):

Metal Oxide ◽

Electron Cyclotron Resonance ◽

Gate Oxide ◽

State Density ◽

Metal Oxide Semiconductor ◽

Trap Density ◽

Oxide Semiconductor ◽

Interface Trap Density ◽

Interface Trap ◽

Conductance Method

AbstractGaN metal oxide semiconductor diodes were demonstrated utilizing MgO as the gate oxide. MgO was grown at 100°C on MOCVD grown n-GaN in a molecular beam epitaxy system using a Mg elemental source and an electron cyclotron resonance oxygen plasma. H3PO4 based wet-chemical etchant was used to remove MgO to expose the underlying n-GaN for ohmic metal deposition. Electron deposited Ti/Al/Pt/Au and Pt/Au were utilized as ohmic and gate metallization, respectively. An interface trap density of low-to-mid 1011 eV-1cm-2was obtained from temperature conductance-voltage measurements. Terman method was also used to estimate the interface trap density and a slight lower number was obtained as compared to the conductance method. Results from elevated temperature (up to 300°C) conductance measurements showed an interface state density roughly three times higher(6x1011 eV–1 cm-2 ) than at 25°C.

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SOME TRANSPORT COEFFICIENTS IN n-TYPE DEGENERATE SEMICONDUCTORS

Canadian Journal of Physics ◽

10.1139/p67-191 ◽

1967 ◽

Vol 45 (7) ◽

pp. 2385-2393 ◽

Cited By ~ 7

Author(s):

Satish Sharma

Keyword(s):

Hall Coefficient ◽

Hall Mobility ◽

Transport Coefficients ◽

Impurity Scattering ◽

Degenerate Semiconductors ◽

Ionized Impurity Scattering ◽

Lorentz Number

In this paper the author has studied the variation of Lorentz number, Hall coefficient, magnetoresistance, and Hall mobility with impurity parameter. The effect of ionized impurity scattering has also been considered.

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CALCULATION OF THE ELECTRON DRIFT MOBILITY IN Cr2+:ZnS AND Cr2+:ZnSe MATERIALS BY RODE ITERATION MODEL

International Journal of Modeling Simulation and Scientific Computing ◽

10.1142/s1793962310000262 ◽

2010 ◽

Vol 01 (04) ◽

pp. 469-475 ◽

Cited By ~ 1

Author(s):

HADI ARABSHAHI

Keyword(s):

Impurity Scattering ◽

Electron Drift ◽

Deformation Potential ◽

Material Parameters ◽

Free Carriers ◽

Relaxation Time Approximation ◽

Ionized Impurity Scattering ◽

Different Temperatures ◽

Iteration Model ◽

Electron Drift Mobility

The results of electron drift velocity in Cr2+:ZnS , and Cr2+:ZnSe are calculated for different temperatures, free-electron concentrations and compositions. The two-mode nature of the polar optic phonons is considered jointly with deformation potential acoustic, piezoelectric, alloy and ionized-impurity scattering. Band non-parabolocity, admixture of p functions, arbitrary degeneracy of the electron distribution, and the screening effects of free carriers on the scattering probabilities are incorporated. The Boltzmann equation is solved by an iterative technique using the currently established values of the material parameters. The iterative results are in fair agreement with other recent calculations obtained using the relaxation-time approximation and experimental methods.

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