Transition energies and direct-indirect band gap crossing in zinc-blende AlxGa1−xN

2013 ◽  
Vol 87 (19) ◽  
Author(s):  
M. Landmann ◽  
E. Rauls ◽  
W. G. Schmidt ◽  
Marcus Röppischer ◽  
Christoph Cobet ◽  
...  
Keyword(s):  
Band Gap ◽  
Transition Energies ◽  
Zinc Blende ◽  
Gap Crossing ◽  
Indirect Band Gap

Organometallic Vapor Phase Epitaxial Growth of ZnGeAs2 and (ZnGeAs2)xGe1−x on GaAs

1988 ◽  
Vol 144 ◽  
Author(s):  
G. S. Solomon ◽  
J. B. Posthill ◽  
M. L. Timmons
Keyword(s):  
Single Crystal ◽  
Band Gap ◽  
Lattice Constant ◽  
Vapor Phase ◽  
Gaas Substrate ◽  
Lattice Mismatch ◽  
Chalcopyrite Structure ◽  
Zinc Blende ◽  
Indirect Band Gap ◽  
Zinc Blende Structure

ABSTRACTEpitaxial single crystal (001) chalcopyrite-structure ZnGeAs2 and single crystal (100) zinc blende-structure (ZnGeAs2)xGe1−x alloys have been grown by organometallic vapor phase epitaxy on (100) GaAs. Selected area electron diffraction was used to determine the crystal structure for several Zn:Ge molar flow ratios. Bulk chemical composition was determined by electron microprobe and correlated to crystal lattice constants obtained from x-ray diffraction. Due to the lattice mismatch between chalcopyrite-structure ZnGeAs2 and the GaAs substrate, the epitaxy is elastically strained, compressing the a-lattice constant and elongating the c-lattice constant. Optical absorption and transmission spectroscopy indicate the zinc-blende-structure material has an indirect band gap of approximately 0.6 eV, whereas the chalcopyrite ZnGeAs2 has a direct band gap of 1.15 eV. Secondary ion mass spectroscopy reveals significant Zn diffusion into the GaAs substrate if the Zn:Ge molar flow ratio exceeds the ratio required for stoichiometric chalcopyrite-structure crystal growth.

scholarly journals Transparent All-Oxide Hybrid NiO:N/TiO2 Heterostructure for Optoelectronic Applications

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 988
Author(s):  
Chrysa Aivalioti ◽  
Alexandros Papadakis ◽  
Emmanouil Manidakis ◽  
Maria Kayambaki ◽  
Maria Androulidaki ◽  
...  
Keyword(s):  
Band Gap ◽  
Single Phase ◽  
Structural Disorder ◽  
Energy Band Gap ◽  
Nitrogen Doped ◽  
Nio Thin Film ◽  
Direct Band ◽  
Output Characteristics ◽  
Indirect Band Gap ◽  
P Type

Nickel oxide (NiO) is a p-type oxide and nitrogen is one of the dopants used for modifying its properties. Until now, nitrogen-doped NiO has shown inferior optical and electrical properties than those of pure NiO. In this work, we present nitrogen-doped NiO (NiO:N) thin films with enhanced properties compared to those of the undoped NiO thin film. The NiO:N films were grown at room temperature by sputtering using a plasma containing 50% Ar and 50% (O2 + N2) gases. The undoped NiO film was oxygen-rich, single-phase cubic NiO, having a transmittance of less than 20%. Upon doping with nitrogen, the films became more transparent (around 65%), had a wide direct band gap (up to 3.67 eV) and showed clear evidence of indirect band gap, 2.50–2.72 eV, depending on %(O2-N2) in plasma. The changes in the properties of the films such as structural disorder, energy band gap, Urbach states and resistivity were correlated with the incorporation of nitrogen in their structure. The optimum NiO:N film was used to form a diode with spin-coated, mesoporous on top of a compact, TiO2 film. The hybrid NiO:N/TiO2 heterojunction was transparent showing good output characteristics, as deduced using both I-V and Cheung’s methods, which were further improved upon thermal treatment. Transparent NiO:N films can be realized for all-oxide flexible optoelectronic devices.

scholarly journals Enhanced luminescence/photodetecting bifunctional devices based on ZnO:Ga microwire/p-Si heterojunction by incorporating Ag nanowires

2021 ◽  
Author(s):  
Mingming Jiang ◽  
Yang Liu ◽  
Ruiming Dai ◽  
Kai Tang ◽  
Peng Wan ◽  
...  
Keyword(s):  
Band Gap ◽  
Carrier Mobility ◽  
Lattice Mismatch ◽  
Semiconductor Materials ◽  
Large Lattice ◽  
Ag Nanowires ◽  
Large Lattice Mismatch ◽  
Enhanced Luminescence ◽  
Indirect Band Gap

Suffering from the indirect band gap, low carrier mobility, and large lattice mismatch with other semiconductor materials, one of the current challenges in Si-based materials and structures is to prepare...

Optical Studies of Poly (N-Carbazole) (PVK) Blending with Polyvinylpyrrolidone (PVP) Using Tauc/Davis-Mott Model

2013 ◽  
Vol 652-654 ◽  
pp. 527-531 ◽  
Author(s):  
A.N. Alias ◽  
T.I. Tunku Kudin ◽  
Z.M. Zabidi ◽  
M.K. Harun ◽  
Ab Malik Marwan Ali ◽  
...  
Keyword(s):  
Band Gap ◽  
Urbach Energy ◽  
Quartz Substrate ◽  
Optical Studies ◽  
Direct Band Gap ◽  
Mott Model ◽  
Blended Polymer ◽  
Electronic Parameters ◽  
Direct Band ◽  
Indirect Band Gap

The optical absorption spectra of blended poly (N-carbazole) (PVK) with polyvinylpyrrolidone (PVP) in various compositions are investigated. A doctor blade technique was used to coat the blended polymer on a quartz substrate. The electronic parameters such as absorption edge (Ee), allowed direct band gap (Ed), allowed indirect band gap (Ei), Urbach edge (Eu) and steepness parameter (γ) were calculated using Tauc/Davis-Mott Model. The results reveal that the Ee, Ed and Ei increase with increasing of PVP ratio. There also have variation changing in Urbach energy and steepness parameter.

Precise Determination of the Direct–Indirect Band Gap Energy Crossover Composition in AlxGa1-xAs

2013 ◽  
Vol 6 (7) ◽  
pp. 071201 ◽  
Author(s):  
Daniel A. Beaton ◽  
Kirstin Alberi ◽  
Brian Fluegel ◽  
Angelo Mascarenhas ◽  
John L. Reno
Keyword(s):  
Band Gap ◽  
Band Gap Energy ◽  
Precise Determination ◽  
Gap Energy ◽  
Indirect Band Gap

Sensitive detection of surface- and size-dependent direct and indirect band gap transitions in ferritin

2014 ◽  
Vol 25 (13) ◽  
pp. 135703 ◽  
Author(s):  
J S Colton ◽  
S D Erickson ◽  
T J Smith ◽  
R K Watt
Keyword(s):  
Band Gap ◽  
Sensitive Detection ◽  
Size Dependent ◽  
Indirect Band Gap

Low temperature photoluminescence study in AlxGa1−xAs alloys in the indirect band gap region (x≳0.4)

1995 ◽  
Vol 78 (8) ◽  
pp. 5090-5097 ◽  
Author(s):  
G. Torres‐Delgado ◽  
R. Castanedo‐Perez ◽  
P. Diaz‐Arencibia ◽  
J. G. Mendoza‐Alvarez ◽  
J. L. Orozco‐Vilchis ◽  
...  
Keyword(s):  
Low Temperature ◽  
Band Gap ◽  
Photoluminescence Study ◽  
Indirect Band Gap ◽  
Low Temperature Photoluminescence
Sign in / Sign up

Export Citation Format

Share Document