Evidence for oxygen being a dominant shallow acceptor in p-type CuI

AbstractYellow luminescence (YL) has been studied in GaN:Mg doped with Mg concentrations ranging from 1019 to 1021 cm−3 by spectral CL (T=5K) and TEM and explained by suggesting that a different mechanism could be responsible for the YL in p-type GaN with respect to that acting in n-type GaN.Transitions at 2.2, 2.8, 3.27, 3.21, and 3.44 eV were found. In addition to the wurtzite phase, TEM showed a different amount of the cubic phase in the samples. Nano tubes with a density of 3×109 cm−2 were also observed by approaching the layer/substrate interface. Besides this, coherent inclusions were found with a diameter in the nm range and a volume fraction of about 1%.The 2.8 eV transition was correlated to a deep level at 600 meV below the conduction band (CB) due to MgGa-VN complexes. The 3.27 eV emission was ascribed to a shallow acceptor at about 170-190 meV above the valence band (VB) due to MgGa.The 2.2 eV yellow band, not present in low doped samples, increased by increasing the Mg concentration. It was ascribed to a transition between a deep donor level at 0.8-1.1 eV below the CB edge due to NGa and the shallow acceptor due to MgGa. This assumption was checked by studying the role of C in Mg compensation. CL spectra from a sample with high C content showed transitions between a C-related 200 meV shallow donor and a deep donor level at about 0.9- 1.1 eV below the CB due to a NGa-VN complex. In our hypothesis this should induce a decrease of the integrated intensity in both the 2.2 and 2.8 eV bands, as actually shown by CL investigations.

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Theory of Defects, Doping, Surfaces and Interfaces in Wide Gap Nitrides

MRS Proceedings ◽

10.1557/proc-423-465 ◽

1996 ◽

Vol 423 ◽

Cited By ~ 1

Author(s):

J. Bernholc ◽

P. Boguslawski ◽

E. L. Briggs ◽

M. Buongiorno Nardelli ◽

B. Chen ◽

...

Keyword(s):

Nearest Neighbor ◽

Group Iv ◽

Type I ◽

Shallow Acceptor ◽

Surface And Interface ◽

Al Content ◽

Surfaces And Interfaces ◽

High Concentrations ◽

P Type ◽

High Al Content

AbstractThe results of extensive theoretical studies of group IV impurities and surface and interface properties of nitrides are presented and compared with available experimental data. Among the impurities, we have considered substitutional C, Si, and Ge. CN is a very shallow acceptor, and thus a promising p-type dopant. Both Si and Ge are excellent donors in GaN. However, in AlGaN alloys the DX configurations are stable for a sufficiently high Al content, which quenches the doping efficiency. At high concentrations, it is energetically favorable for group IV impurities to form nearest-neighbor Xcation-XN pairs. Turning to surfaces, AIN is known to exhibit NEA. We find that the NEA property depends sensitively on surface reconstruction and termination. At interfaces, the strain effects on the band offsets range from 20% to 40%, depending on the substrate. The AIN/GaN/InN interfaces are all of type I, while the A10.5Ga0.5 N/A1N zinc-blende (001) interface may be of type II. Further, the calculated bulk polarizations in wurtzite AIN and GaN are -1.2 and -0.45 μC/cm2, respectively, and the interface contribution to the polarization in the GaN/AlN wurtzite multi-quantum-well is small.

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Deep level related yellow luminescence in p-type GaN grown by MBE on (0001) sapphire

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300005032 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 754-760

Author(s):

Giancarlo Salviati ◽

Nicola Armani ◽

Carlo Zanotti-Fregonara ◽

Enos Gombia ◽

Martin Albrecht ◽

...

Keyword(s):

Volume Fraction ◽

Deep Level ◽

Cubic Phase ◽

Donor Level ◽

Yellow Luminescence ◽

Wurtzite Phase ◽

Shallow Acceptor ◽

Deep Donor ◽

P Type ◽

Deep Donor Level

Yellow luminescence (YL) has been studied in GaN:Mg doped with Mg concentrations ranging from 1019 to 1021 cm-3 by spectral CL (T=K) and TEM and explained by suggesting that a different mechanism could be responsible for the YL in p-type GaN with respect to that acting in n-type GaN.Transitions at 2.2, 2.8, 3.27, 3.21, and 3.44 eV were found. In addition to the wurtzite phase, TEM showed a different amount of the cubic phase in the samples. Nano tubes with a density of 3×109 cm−2 were also observed by approaching the layer/substrate interface. Besides this, coherent inclusions were found with a diameter in the nm range and a volume fraction of about 1%.The 2.8 eV transition was correlated to a deep level at 600 meV below the conduction band (CB) due to MgGa-VN complexes. The 3.27 eV emission was ascribed to a shallow acceptor at about 170-190 meV above the valence band (VB) due to MgGa.The 2.2 eV yellow band, not present in low doped samples, increased by increasing the Mg concentration. It was ascribed to a transition between a deep donor level at 0.8-1.1 eV below the CB edge due to NGa and the shallow acceptor due to MgGa. This assumption was checked by studying the role of C in Mg compensation. CL spectra from a sample with high C content showed transitions between a C-related 200 meV shallow donor and a deep donor level at about 0.9-1.1 eV below the CB due to a NGa-VN complex. In our hypothesis this should induce a decrease of the integrated intensity in both the 2.2 and 2.8 eV bands, as actually shown by CL investigations.

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Non-axial NO-VZn shallow acceptor complexes in nitrogen implanted p-type ZnO thin films

Applied Surface Science ◽

10.1016/j.apsusc.2020.147168 ◽

2020 ◽

Vol 529 ◽

pp. 147168

Author(s):

Wanjun Li ◽

Hong Zhang ◽

Xiaoyu Zhang ◽

Guoping Qin ◽

Honglin Li ◽

...

Keyword(s):

Thin Films ◽

Zno Thin Films ◽

Shallow Acceptor ◽

P Type

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Shallow acceptor and hydrogen impurity in p-type arsenic-doped ZnMgO films grown by radio frequency magnetron sputtering

Semiconductor Science and Technology ◽

10.1088/0268-1242/25/8/085009 ◽

2010 ◽

Vol 25 (8) ◽

pp. 085009 ◽

Cited By ~ 10

Author(s):

J C Fan ◽

G W Ding ◽

S Fung ◽

Z Xie ◽

Y C Zhong ◽

...

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

Hydrogen Impurity ◽

Shallow Acceptor ◽

P Type

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Dissociation Kinetics of Shallow-Acceptor-Hydrogen Pairs in Silicon

MRS Proceedings ◽

10.1557/proc-163-443 ◽

1989 ◽

Vol 163 ◽

Cited By ~ 4

Author(s):

T. Zundel ◽

J. Weber

Keyword(s):

Schottky Diode ◽

Reverse Bias ◽

Temperature Dependent ◽

Dissociation Kinetics ◽

Shallow Acceptor ◽

Dissociation Energies ◽

Type Silicon ◽

P Type ◽

Kinetics Of

AbstractAnnealing of hydrogenated p-type silicon with a reverse bias applied to a Schottky diode allows us to precisely determine the dissociation frequency vA of shallow acceptor-hydrogen pairs (AH with A = B, Al, Ga, and In). The temperature dependent values of vA satisfy the relation vA = voAexp (-EA/kT), with voB = 2.8 . 1014 s-1, voAl = 3.1 . 1013 s-1, VoGa = 6.9 . 1013 s-1, and voIn = 8.4 · 1013 s-1. The dissociation energies EA depend only weakly on the acceptors: EB = (1.28±0.03)eV, EAl = (1.44±0.02) eV, EGa = (1.40±0.03) eV, and EIn = (1.42±0.05) eV. The dissociation frequency of BH pairs shifts to a lower value when H is replaced by the deuterium isotope.

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Impurity Doping in Mg(OH)2 for n-Type and p-Type Conductivity Control

Materials ◽

10.3390/ma13132972 ◽

2020 ◽

Vol 13 (13) ◽

pp. 2972

Author(s):

Masaya Ichimura

Keyword(s):

First Principles ◽

Energy Levels ◽

Wide Bandgap ◽

First Principles Calculations ◽

Substitutional Site ◽

Shallow Acceptor ◽

Impurity Doping ◽

Trivalent Cations ◽

Valence Control ◽

P Type

Magnesium hydroxide (Mg(OH)2) has a wide bandgap of about 5.7 eV and is usually considered an insulator. In this study, the energy levels of impurities introduced into Mg(OH)2 are predicted by first-principles calculations. A supercell of brucite Mg(OH)2 consisting of 135 atoms is used for the calculations, and an impurity atom is introduced either at the substitutional site replacing Mg or the interlayer site. The characteristics of impurity levels are predicted from density-of-states analysis for the charge-neutral cell. According to the results, possible shallow donors are trivalent cations at the substitutional site (e.g., Al and Fe) and cation atoms at the interlayer site (Cu, Ag, Na, and K). On the other hand, an interlayer F atom can be a shallow acceptor. Thus, valence control by impurity doping can turn Mg(OH)2 into a wide-gap semiconductor useful for electronics applications.

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Tuning the Carrier Type and Density of Monolayer Tin Selenide via Organic Molecular Doping

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac3691 ◽

2021 ◽

Author(s):

Yu Jie Zheng ◽

Qi Zhang ◽

Omololu Odunmbaku ◽

Zeping Ou ◽

Meng Li ◽

...

Keyword(s):

Charge Transfer ◽

Organic Molecules ◽

Single Layer ◽

Conduction Band Edge ◽

Shallow Acceptor ◽

Tin Selenide ◽

Lowest Unoccupied Molecular Orbital ◽

Molecular Doping ◽

P Type ◽

Highest Occupied Molecular Orbitals

Abstract Utilizing first-principles calculations, charge transfer doping process of single layer tin selenide (SL-SnSe) via the surface adsorption of various organic molecules was investigated. Effective p-type SnSe, with carrier concentration exceeding 3.59×1013 cm-2, was obtained upon adsorption of tetracyanoquinodimethane (TCNQ) or 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-quinodimethane (F4TCNQ) on SL-SnSe due to their lowest unoccupied molecular orbital (LUMO) acting as shallow acceptor states. While we could not obtain effective n-type SnSe through adsorption of tetrathiafulvalene (TTF) or 1,4,5,8-tetrathianaphthalene (TTN) on pristine SnSe due to their highest occupied molecular orbitals (HOMO) being far from the conduction band edge of SnSe, this disadvantageous situation can be amended by the introduction of an external electric field perpendicular to the monolayer surface. It is found that Snvac will facilitate charge transfer from TTF to SnSe through introducing an unoccupied gap state just above the HOMO of TTF, thereby partially compensating for the p-type doping effect of Snvac. Our results show that both effective p-type and n-type SnSe can be obtained and tuned by charge transfer doping, which is necessary to promote its applications in nanoelectronics, thermoelectrics and optoelectronics.

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