Optical and EPR Study of Defects in Cadmium Germanium Arsenide

2002 ◽  
Vol 744 ◽  
Author(s):  
Lihua Bai ◽  
N. Y. Garces ◽  
Nanying Yang ◽  
P. G. Schunemann ◽  
S. D. Setzler ◽  
...  
Keyword(s):  
Absorption Band ◽  
Optical Absorption ◽  
Room Temperature ◽  
Hole Concentration ◽  
Paramagnetic Defect ◽  
Paramagnetic Resonance ◽  
Anion Site ◽  
Shallow Acceptors ◽  
P Type ◽  
Cadmium Germanium Arsenide

ABSTRACTBulk crystals of CdGeAs2 have been characterized using photoluminescence (PL), optical absorption, Hall effect, and electron paramagnetic resonance (EPR) techniques. An absorption band near 5.5 microns at room temperature is observed in all of the p-type samples we have studied. A correlation between the magnitude of this optical absorption and the excess hole concentration at room temperature is established. Also, an EPR signal is found to correlate with the strength of this absorption band. PL data are consistent with an increased concentration of shallow acceptors being present in high-absorption samples. From the EPR data, we suggest that a model for the paramagnetic defect associated with the absorption at 5.5 microns may be an acceptor on an anion site.

GalnAsSb Materials for Thermophotovoltaics

1996 ◽  
Vol 450 ◽  
Author(s):  
C. A. Wang ◽  
G. W. Turner ◽  
M. J. Manfra ◽  
H. K. Choi ◽  
D. L. Spears
Keyword(s):  
Room Temperature ◽  
Molecular Beam ◽  
Hole Concentration ◽  
Organometallic Vapor Phase Epitaxy ◽  
Room Temperature Photoluminescence ◽  
P Type ◽  
First Time ◽  
Lattice Matched ◽  
Comparable Quality ◽  
Peak Emission

ABSTRACTGai1−xInxASySb1-y (0.06 < x < 0.18, 0.05 < y < 0.14) epilayers were grown lattice-matched to GaSb substrates by low-pressure organometallic vapor phase epitaxy (OMVPE) using triethylgallium, trimethylindium, tertiarybutylarsine, and trimethylantimony. These epilayers have a mirror-like surface morphology, and exhibit room temperature photoluminescence (PL) with peak emission wavelengths (λP,300K) out to 2.4 μm. 4K PL spectra have a full width at half-maximum of 11 meV or less for λP,4K < 2.1 μm (λP,300K = 2.3 μm). Nominally undoped layers are p-type with typical 300K hole concentration of 9 × 1015 cm−3 and mobility ∼ 450 to 580 cm2/V-s for layers grown at 575°C. Doping studies are reported for the first time for GalnAsSb layers doped n type with diethyltellurium and p type with dimethylzinc. Test diodes of p-GalnAsSb/n-GaSb have an ideality factor that ranges from 1.1 to 1.3. A comparison of electrical, optical, and structural properties of epilayers grown by molecular beam epitaxy indicates OMVPE-grown layers are of comparable quality.

The Properties of GaInAsSb/GaSb Heterostructure Grown by Mocvd and P-GaInAsSb/N-GaSb Photodiodes

1995 ◽  
Vol 415 ◽  
Author(s):  
Baolin Zhang ◽  
Yixin Jin ◽  
Tianming Zhou ◽  
Hong Jiang ◽  
Yongqiang Ning ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Room Temperature ◽  
Metalorganic Chemical Vapor Deposition ◽  
Hole Concentration ◽  
Chemical Vapor ◽  
Infrared Transmission ◽  
Long Wavelength ◽  
Measurement Results ◽  
P Type ◽  
Metalorganic Chemical

ABSTRACTGaInAsSb/GaSb heterostructures have been grown by metalorganic chemical vapor deposition (MOCVD). The optical properties were characterized using low temperature(71K) photoluminescence(PL) and infrared transmission spectroscopy. The FWHM of the typical PL spectrum peaked at 2.3μm is 30meV. Hall measurement results for undoped GaInAsSb layers are presented showing a p-type background and low hole concentration of 6.5 × 1015cm−3. The room temperature performances of the p-GaInAsSb/n-GaSb photodiodes are reported. Its responsivity spectrum is peaked at 2.2 5μm and cuts off at 1.7μm in the short wavelength and at 2.4μm in the long wavelength, respectively. The room temperature detectivity D* is of 1 × 109cm.Hz1/2.W−2

Manipulation of Room Temperature Ferromagnetic behavior of GaMnN Epilayers

2009 ◽  
Vol 1198 ◽  
Author(s):  
Neeraj Nepal ◽  
M. Oliver Luen ◽  
Pavel Frajtag ◽  
John Zavada ◽  
Salah M. Bedair ◽  
...  
Keyword(s):  
Room Temperature ◽  
Hole Concentration ◽  
Chemical Vapor ◽  
Multilayer Structures ◽  
Organic Chemical ◽  
Ferromagnetic Behavior ◽  
Chemical Vapor Deposition Growth ◽  
Metal Organic ◽  
P Type ◽  
Organic Chemical Vapor Deposition

AbstractWe report on metal organic chemical vapor deposition growth of GaMnN/p-GaN/n-GaN multilayer structures and manipulation of room temperature (RT) ferromagnetism (FM) in a GaMnN layer. The GaMnN layer was grown on top of a n-GaN substrate and found to be almost always paramagnetic. However, when grown on a p-type GaN layer, a strong saturation magnetization (Ms) was observed. Ms was almost doubled after annealing demonstrating that the FM observed in GaMnN film is carrier-mediated. To control the hole concentration of the p-GaN layer by depletion, GaMnN/p-GaN/n-GaN multilayer structures of different p-GaN thickness (Xp) were grown on sapphire substrates. We have demonstrated that the FM depends on the Xp and the applied bias to the GaN p-n junction. The FM of these multilayer is independent on the top GaMnN layer thickness (tGaMnN) for tGaMnN >200 nm and decreases for tGaMnN < 200 nm. Thus the room temperature FM of GaMnN i-p-n structure can also be controlled by changing Xp and tGaMnN in the GaMnN i-p-n structures.

ESR and Optical Absorption Spectra of Copper (II) Ions in Glasses

2008 ◽  
Vol 55-57 ◽  
pp. 849-852 ◽  
Author(s):  
Jakrapong Kaewkhao ◽  
S. Rhianphumikarakit ◽  
N. Udomkan
Keyword(s):  
Absorption Band ◽  
Optical Absorption ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Light Blue ◽  
Jahn Teller ◽  
Doped Glasses ◽  
Jahn Teller Effect ◽  
G Value ◽  
Cu Ions

Glasses in the system 20Na2O-Al2O3-13B2O3-6.3CaO-0.2Sb2O3-1.5PbO2-(58-x)SiO2-xCuO were prepared with x = 0.0, 0.2, 0.4, 0.6 and 0.8 mol% respectively. ESR absorption spectra due to Cu2+ (3d9) ions show that the ESR signal at 0.2 and 0.4 mol%CuO were similarity, the perpendicular g-value,g^ can be observed at 2.06 whereas the parallel g-value,g// cannot be observed. The line width of board line centers were depends on the increasing of concentration of CuO-doped. CuO-doped glasses give rise light blue green color. Confirm from optical absorption techniques as UV-VIS measurment reported were recorded at room temperature. The absorption band near 800 nm (2B1g®2B2g) is due to Jahn-Teller effect of Cu2+. Also absorption band at around 400 nm (2B1g®2Eg) could be found due to d-d transition of Cu2+ ion in the CuO doped glasses. The results obtained suggest that Cu ions substitutes as an accepted center for [SiO2]4+ in oxygen octahedral rhombohedral distortion.

P-type InxGa1−xN semibulk templates (0.02 < x < 0.16) with room temperature hole concentration of mid-1019 cm−3 and device quality surface morphology

2021 ◽  
Vol 119 (12) ◽  
pp. 122101
Author(s):  
Evyn L. Routh ◽  
Mostafa Abdelhamid ◽  
Peter Colter ◽  
N. A. El-Masry ◽  
S. M. Bedair
Keyword(s):  
Surface Morphology ◽  
Room Temperature ◽  
Hole Concentration ◽  
P Type ◽  
Quality Surface

p-type in ZnO:N by codoping with Cr

2003 ◽  
Vol 786 ◽  
Author(s):  
E. Kaminska ◽  
A. Piotrowska ◽  
J. Kossut ◽  
R. Butkute ◽  
W. Dobrowolski ◽  
...  
Keyword(s):  
Time Scale ◽  
Room Temperature ◽  
Surface Passivation ◽  
Hole Concentration ◽  
Rf Sputtering ◽  
Zno Films ◽  
Type Conductivity ◽  
Chromium Doping ◽  
P Type ◽  
Over Time

ABSTRACTWe report on the fabrication of p-ZnO films by thermal oxidation of Zn3N2 deposited by reactive rf sputtering. With additional chromium doping we achieved p-type conductivity with the hole concentration ∼5×1017cm−3 and the mobility of 23.6 cm2/Vs at room temperature. We developed a method of surface passivation of p-ZnO that maintains its p-type conductivity over time-scale of months.

scholarly journals Reactively Sputtered Sb-GaN Films and its Hetero-Junction Diode: The Exploration of the n-to-p Transition

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 210
Author(s):  
Cao Phuong Thao ◽  
Thi Tran Anh Tuan ◽  
Dong-Hau Kuo ◽  
Wen-Cheng Ke ◽  
Thach Thi Via Sa Na
Keyword(s):  
Radio Frequency ◽  
Hole Concentration ◽  
Reactive Sputtering ◽  
Bandgap Energy ◽  
Electrical Characteristics ◽  
Cation Site ◽  
N2 Atmosphere ◽  
Anion Site ◽  
Highly Mismatched Alloys ◽  
P Type

Sb anion-substituted gallium nitride films were fabricated by radio frequency reactive sputtering with single Sb-containing cermet targets with different Sb contents under Ar/N2 atmosphere. n-type GaN films with electron concentration of (1.40 ± 0.1) × 1017 cm−3 inverted to p-type Sb-GaN with hole concentration of (5.50 ± 0.3) × 1017 cm−3. The bandgap energy of Sb anion-added Sb-GaN films decreased from 3.20 to 2.72 eV with increasing Sb concentration. The formation of p-type Sb-GaN is attributed to the formation of Ga vacancy at higher Sb concentration. The coexistence of Sb at the Ga cation site and N anion site is an interesting and important result, as GaNSb had been well developed for highly mismatched alloys. The hetero-junction with p-type Sb-GaN/n-Si diodes was all formed by radio frequency (RF) reactive sputtering technology. The electrical characteristics of Sb-GaN diode devices were investigated from −20 to 20 V at room temperature (RT).

Hydrogenation of Gallium Nitride

1993 ◽  
Vol 325 ◽  
Author(s):  
M. S. Brandt ◽  
N. M. Johnson ◽  
R. J. Molnar ◽  
R. Singh ◽  
T. D. Moustakas
Keyword(s):  
Comparative Study ◽  
Conduction Band ◽  
Room Temperature ◽  
Hole Concentration ◽  
Conduction Band Edge ◽  
Order Of Magnitude ◽  
Si Doped ◽  
Donor State ◽  
P Type ◽  
Mg Doped

AbstractA comparative study of the effects of hydrogen in n-type (unintentionally and Si-doped) as well as p-type (Mg-doped) MBE-grown GaN is presented. Hydrogenation above 500°C reduces the hole concentration at room temperature in the p-type material by one order of magnitude. Three different microscopic effects of hydrogen are suggested: Passivation of deep defects and of Mg-acceptors due to formation of hydrogen-related complexes and the introduction of a hydrogenrelated donor state 100 meV below the conduction band edge.

Electron Paramagnetic Resonance and Optical Absorption Spectra of VO2+ in CsCl Single Crystals

1985 ◽  
Vol 40 (5) ◽  
pp. 511-515 ◽  
Author(s):  
G. Elbers ◽  
G. Lehmann
Keyword(s):  
Optical Absorption ◽  
Absorption Spectra ◽  
Room Temperature ◽  
Ligand Field ◽  
Optical Absorption Spectra ◽  
Paramagnetic Resonance ◽  
Rapid Rotation ◽  
Vanadyl Ion ◽  
Vibrational Progression ◽  
Electron Paramagnetic

In vanadium-doped CsCl crystals grown from aqueous solutions anisotropic EPR spectra due to VO2+ are observed and analyzed at room temperature. Evidence is presented that isotropic spectra of this ion observed in this and other compounds are due to inclusions of growth solution and not to rapid rotation of the vanadyl ion in the solid as normally assumed. At 77 K a well resolved vibrational progression of about 820 cm −1 is observed in the first ligand field band of this ion. The optical absorption spectra indicate the presence of a second valence state of vanadium, most likely V3+, in varying proportions depending on the crystal growth temperature.

Pl And Epr Spectroscopy Of Point Defects In Detector-Grade Cd1−xZnxTe

1997 ◽  
Vol 487 ◽  
Author(s):  
C. I. Rablau ◽  
S. D. Setzler ◽  
L. E. Halliburton ◽  
F. P. Doty ◽  
N. C. Giles
Keyword(s):  
Point Defects ◽  
Room Temperature ◽  
Gamma Ray ◽  
Paramagnetic Resonance ◽  
X Ray ◽  
Shallow Donors ◽  
Shallow Acceptors ◽  
Epr Signal ◽  
And Control ◽  
Electron Paramagnetic

AbstractCadmium zinc telluride (CdZnTe) is an emerging material for room-temperature x-ray and gamma ray detectors. The identification and control of point defects and charge compensators are currently important issues. Low-temperature photoluminescence (PL) and electron paramagnetic resonance (EPR) spectroscopies have been used to characterize point defects in CdZnTe crystals grown by the high-pressure Bridgman technique. Luminescence due to shallow donors, shallow acceptors, and deeper acceptors was monitored for a series of samples. An isotropic EPR signal attributed to shallow hydrogenic donors is observed in all samples, and the concentration of shallow donors has been determined. The nature of the defect centers (impurities, vacancies, vacancy-impurity complexes), and the correlation between defect concentration and device performance is discussed.

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