n- and p-type ohmic contacts at monolayer gallium nitride–metal interfaces

Recently, two-dimensional (2D) gallium nitride (GaN) was experimentally fabricated, and has promising applications in next-generation electronic and optoelectronic devices.

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The Microstructure and Electrical Properties of Directly Deposited TiN Ohmic Contacts to Gallium Nitride.

MRS Proceedings ◽

10.1557/proc-595-f99w11.75 ◽

1999 ◽

Vol 595 ◽

Author(s):

P. Ruterana ◽

G. Nouet ◽

Th. Kehagias ◽

Ph. Komninou ◽

Th. Karakostas ◽

...

Keyword(s):

Gallium Nitride ◽

Electrical Properties ◽

Film Thickness ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Epitaxial Relationship ◽

Si Doped ◽

P Type ◽

20 Nm

AbstractWhen the stoichiometric TiN was deposited directly on GaN, we obtained columnar TiN grains of 5-20 nm section which cross the whole film thickness and are rotated mostly around the [111] axis. The conventional epitaxial relationship is obtained and no amorphous patches are observed at the interface. The deposition of TiN on Si doped GaN layers lead to the formation of an ohmic contact, whereas we obtain a rectifying contact on p type layers.

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Diverse electronic properties of 2D layered Se-containing materials composed of quasi-1D atomic chains

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05914h ◽

2020 ◽

Vol 22 (4) ◽

pp. 2122-2129 ◽

Cited By ~ 2

Author(s):

Yawen Li ◽

Yuanhui Sun ◽

Guangren Na ◽

Wissam A. Saidi ◽

Lijun Zhang

Keyword(s):

Electronic Properties ◽

Optoelectronic Devices ◽

Layered Materials ◽

Two Dimensional ◽

Next Generation ◽

Atomic Chains ◽

Significant Attention

The two-dimensional (2D) atomically thin layered materials have attracted significant attention for constructing next-generation integrated electronic and optoelectronic devices.

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Contacts to High Aluminum Fraction p-type Aluminum Gallium Nitride

MRS Proceedings ◽

10.1557/proc-743-l12.2 ◽

2002 ◽

Vol 743 ◽

Cited By ~ 2

Author(s):

Brett A. Hull ◽

Suzanne E. Mohney ◽

Uttiya Chowdhury ◽

Russell D. Dupuis ◽

David Gotthold ◽

...

Keyword(s):

Gallium Nitride ◽

Aluminum Gallium Nitride ◽

Ohmic Contacts ◽

Contact Resistivity ◽

Rapid Degradation ◽

Current Voltage ◽

P Type ◽

High Aluminum ◽

Mg Doped ◽

Palladium Platinum

ABSTRACTGold, palladium, platinum or nickel ohmic contacts on Mg doped p-type AlxGa1-xN with x = 0.4 and x = 0.45 have been examined. The Au contact provided the lowest contact resistivity with pc = 1.8 (± 1.1) x 10−3 Ωcm2, but only following annealing at 850°C. For the Pd, Au, and Pt contacts annealed at greater than 700°C, a rapid degradation in the current-voltage curves was observed upon testing. The degradation was induced by exposure to sub-bandgap light and was reversed with a mild anneal at 500°C. Possible mechanisms for the degradation are discussed.

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Study the Catalyst Effect of NaCl on MoS2 Growth in Chemical Vapor Deposition Process

CrystEngComm ◽

10.1039/d1ce00525a ◽

2021 ◽

Author(s):

Long Chen ◽

Lingyu Zang ◽

Luhua Chen ◽

Jinchao Wu ◽

Chengming Jiang ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Structural Characteristics ◽

Optoelectronic Devices ◽

Chemical Vapor ◽

Deposition Process ◽

Two Dimensional ◽

Next Generation ◽

Cvd Growth ◽

Catalyst Effect

Due to the unique two-dimensional (2D) structural characteristics, the mono-layer MoS2 is considered to be an ideal material for next-generation optoelectronic devices. At present, the chemical vapor deposition (CVD) growth...

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The microstructure and electrical properties of directly deposited TiN ohmic contacts to Gallium Nitride.

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300005226 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 887-893

Author(s):

P. Ruterana ◽

G. Nouet ◽

Th. Kehagias ◽

Ph. Komninou ◽

Th. Karakostas ◽

...

Keyword(s):

Gallium Nitride ◽

Electrical Properties ◽

Film Thickness ◽

Ohmic Contact ◽

Ohmic Contacts ◽

Epitaxial Relationship ◽

Si Doped ◽

P Type ◽

20 Nm

When the stoichiometric TiN was deposited directly on GaN, we obtained columnar TiN grains of 5-20 nm section which cross the whole film thickness and are rotated mostly around the [111] axis. The conventional epitaxial relationship is obtained and no amorphous patches are observed at the interface. The deposition of TiN on Si doped GaN layers lead to the formation of an ohmic contact, whereas we obtain a rectifying contact on p type layers.

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A TEM Study of Cr Based Contacts to (0001) 6H-SiC

Microscopy and Microanalysis ◽

10.1017/s1431927600037818 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 1064-1065

Author(s):

R.-J. Liu ◽

M. J. Kim ◽

R. W. Carpenter ◽

L. M. Porter ◽

L. P. Scheunemann ◽

...

Keyword(s):

Ohmic Contacts ◽

Optoelectronic Devices ◽

Wide Band ◽

Electron Beam Evaporation ◽

Rapid Thermal Anneal ◽

Wide Band Gap ◽

Ohmic Behavior ◽

Transmission Electron ◽

P Type ◽

Sic Films

6H-SiC is a wide band-gap semiconductor. In recent years, a variety of high-power, -temperature, -speed and optoelectronic devices have been produced in SiC films. The search for metals which can form thermally stable, uniform ohmic contacts with SiC with low resistivity is still ongoing. In this study, Cr and CrBx (1<x<2) films were deposited by electron beam evaporation onto p-type, vicinal Si-terminated (0001) 6H-SiC surface. Both contacts exhibited rectifying behavior in the as-deposited condition. Ohmic-like behavior was observed for Cr/SiC system after annealing at 1000 °C for 240 seconds in a rapid thermal anneal furnace in an Ar atmosphere. It was also reported that ohmic behavior was observed for CrB2 /SiC system after annealing at 1100 °C for 2 minutes at a pressure of 5x10“7 Torr.2 The microstructure and chemistry of these two contact systems in both as-deposited and annealed conditions were investigated by transmission electron microscopy (TEM).

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Tunable Schottky Barrier and Interfacial Electronic Properties in Graphene/ZnSe Heterostructures

Frontiers in Chemistry ◽

10.3389/fchem.2021.744977 ◽

2021 ◽

Vol 9 ◽

Author(s):

Wenjun Xiao ◽

Tianyun Liu ◽

Yuefei Zhang ◽

Zhen Zhong ◽

Xinwei Zhang ◽

...

Keyword(s):

Electronic Properties ◽

Schottky Barrier ◽

First Principles ◽

Schottky Barrier Height ◽

Optoelectronic Devices ◽

Strain Condition ◽

Two Dimensional ◽

Photoelectric Device ◽

Horizontal Strain ◽

P Type

With a direct bandgap, two-dimensional (2D) ZnSe is a promising semiconductor material in photoelectric device fields. In this work, based on first-principles methods, we theoretically studied the modulation of the Schottky barrier height (SBH) by applying horizontal and vertical strains on graphene/ZnSe heterojunction. The results show that the inherent electronic properties of graphene and ZnSe monolayers are both well-conserved because of the weak van der Waals (vdW) forces between two sublayers. Under horizontal strain condition, the n(p)-type SBH decreases from 0.56 (1.62) eV to 0.21 (0.78) eV. By changing the interlayer distance in the range of 2.8 Å to 4.4 Å, the n(p)-type SBH decreases (increases) from 0.88 (0.98) eV to 0.21 (1.76) eV. These findings prove the SBH of the heterojunction to be tuned effectively, which is of great significance to optoelectronic devices, especially in graphene/ZnSe-based nano-electronic and optoelectronic devices.

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A polarization-induced 2D hole gas in undoped gallium nitride quantum wells

Science ◽

10.1126/science.aau8623 ◽

2019 ◽

Vol 365 (6460) ◽

pp. 1454-1457 ◽

Cited By ~ 13

Author(s):

Reet Chaudhuri ◽

Samuel James Bader ◽

Zhen Chen ◽

David A. Muller ◽

Huili Grace Xing ◽

...

Keyword(s):

Gallium Nitride ◽

Quantum Wells ◽

Electron Gas ◽

Wide Bandgap ◽

Two Dimensional ◽

Cryogenic Temperatures ◽

Nitride Semiconductors ◽

Valence Band Structure ◽

Bandgap Semiconductors ◽

P Type

A high-conductivity two-dimensional (2D) hole gas, analogous to the ubiquitous 2D electron gas, is desirable in nitride semiconductors for wide-bandgap p-channel transistors. We report the observation of a polarization-induced high-density 2D hole gas in epitaxially grown gallium nitride on aluminium nitride and show that such hole gases can form without acceptor dopants. The measured high 2D hole gas densities of about 5 × 1013 per square centimeters remain unchanged down to cryogenic temperatures and allow some of the lowest p-type sheet resistances among all wide-bandgap semiconductors. The observed results provide a probe for studying the valence band structure and transport properties of wide-bandgap nitride interfaces.

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