Infrared dielectric functions, phonon modes, and free-charge carrier properties of high-Al-content AlxGa1−xN alloys determined by mid infrared spectroscopic ellipsometry and optical Hall effect

2017 ◽  
Vol 121 (20) ◽  
pp. 205701 ◽  
Author(s):  
S. Schöche ◽  
T. Hofmann ◽  
D. Nilsson ◽  
A. Kakanakova-Georgieva ◽  
E. Janzén ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Hall Effect ◽  
Spectroscopic Ellipsometry ◽  
Free Charge Carrier ◽  
Free Charge ◽  
Phonon Modes ◽  
Mid Infrared ◽  
Al Content ◽  
Optical Hall Effect ◽  
High Al Content

scholarly journals Cavity-enhanced optical Hall effect in two-dimensional free charge carrier gases detected at terahertz frequencies

2015 ◽  
Vol 40 (12) ◽  
pp. 2688 ◽  
Author(s):  
S. Knight ◽  
S. Schöche ◽  
V. Darakchieva ◽  
P. Kühne ◽  
J.-F. Carlin ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Hall Effect ◽  
Free Charge Carrier ◽  
Two Dimensional ◽  
Free Charge ◽  
Terahertz Frequencies ◽  
Carrier Gases ◽  
Optical Hall Effect

scholarly journals Infrared to vacuum-ultraviolet ellipsometry and optical Hall-effect study of free-charge carrier parameters in Mg-doped InN

2013 ◽  
Vol 113 (1) ◽  
pp. 013502 ◽  
Author(s):  
S. Schöche ◽  
T. Hofmann ◽  
V. Darakchieva ◽  
N. Ben Sedrine ◽  
X. Wang ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Hall Effect ◽  
Vacuum Ultraviolet ◽  
Free Charge Carrier ◽  
Effect Study ◽  
Free Charge ◽  
Optical Hall Effect ◽  
Mg Doped

scholarly journals In-situ terahertz optical Hall effect measurements of ambient effects on free charge carrier properties of epitaxial graphene

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Sean Knight ◽  
Tino Hofmann ◽  
Chamseddine Bouhafs ◽  
Nerijus Armakavicius ◽  
Philipp Kühne ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Hall Effect ◽  
Free Charge Carrier ◽  
Epitaxial Graphene ◽  
Free Charge ◽  
Hall Effect Measurements ◽  
Optical Hall Effect

scholarly journals Anisotropy, phonon modes, and free charge carrier parameters in monoclinicβ-gallium oxide single crystals

2016 ◽  
Vol 93 (12) ◽  
Author(s):  
M. Schubert ◽  
R. Korlacki ◽  
S. Knight ◽  
T. Hofmann ◽  
S. Schöche ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Single Crystals ◽  
Gallium Oxide ◽  
Free Charge Carrier ◽  
Free Charge ◽  
Phonon Modes

scholarly journals Free-charge carrier parameters of n-type, p-type and compensated InN:Mg determined by infrared spectroscopic ellipsometry

2014 ◽  
Vol 571 ◽  
pp. 384-388 ◽  
Author(s):  
S. Schöche ◽  
T. Hofmann ◽  
V. Darakchieva ◽  
X. Wang ◽  
A. Yoshikawa ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Spectroscopic Ellipsometry ◽  
Free Charge Carrier ◽  
Free Charge ◽  
Infrared Spectroscopic ◽  
P Type

scholarly journals Critical View on Buffer Layer Formation and Monolayer Graphene Properties in High-Temperature Sublimation

2021 ◽  
Vol 11 (4) ◽  
pp. 1891
Author(s):  
Vallery Stanishev ◽  
Nerijus Armakavicius ◽  
Chamseddine Bouhafs ◽  
Camilla Coletti ◽  
Philipp Kühne ◽  
...  
Keyword(s):  
High Temperature ◽  
Charge Carrier ◽  
Buffer Layer ◽  
Free Charge Carrier ◽  
Monolayer Graphene ◽  
Free Charge ◽  
Layer Formation ◽  
Free Hole ◽  
Sublimation Growth ◽  
Insulating Substrates

In this work we have critically reviewed the processes in high-temperature sublimation growth of graphene in Ar atmosphere using closed graphite crucible. Special focus is put on buffer layer formation and free charge carrier properties of monolayer graphene and quasi-freestanding monolayer graphene on 4H–SiC. We show that by introducing Ar at higher temperatures, TAr, one can shift the formation of the buffer layer to higher temperatures for both n-type and semi-insulating substrates. A scenario explaining the observed suppressed formation of buffer layer at higher TAr is proposed and discussed. Increased TAr is also shown to reduce the sp3 hybridization content and defect densities in the buffer layer on n-type conductive substrates. Growth on semi-insulating substrates results in ordered buffer layer with significantly improved structural properties, for which TAr plays only a minor role. The free charge density and mobility parameters of monolayer graphene and quasi-freestanding monolayer graphene with different TAr and different environmental treatment conditions are determined by contactless terahertz optical Hall effect. An efficient annealing of donors on and near the SiC surface is suggested to take place for intrinsic monolayer graphene grown at 2000 ∘C, and which is found to be independent of TAr. Higher TAr leads to higher free charge carrier mobility parameters in both intrinsically n-type and ambient p-type doped monolayer graphene. TAr is also found to have a profound effect on the free hole parameters of quasi-freestanding monolayer graphene. These findings are discussed in view of interface and buffer layer properties in order to construct a comprehensive picture of high-temperature sublimation growth and provide guidance for growth parameters optimization depending on the targeted graphene application.

Selective observation of transverse optical phonons of Au modes to evaluate free charge carrier parameters in β-Ga2O3 substrate and homoepitaxial film

2021 ◽  
Vol 118 (25) ◽  
pp. 252101
Author(s):  
Takeyoshi Onuma ◽  
Kohei Sasaki ◽  
Tomohiro Yamaguchi ◽  
Tohru Honda ◽  
Akito Kuramata ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Free Charge Carrier ◽  
Transverse Optical ◽  
Optical Phonons ◽  
Free Charge ◽  
Homoepitaxial Film

Free charge carrier repartition over the surface of photosensitive materials: Why and how to manage?

2008 ◽  
Vol 78 (5) ◽  
pp. 1070-1080 ◽  
Author(s):  
A. A. Evstratov ◽  
C. Chis ◽  
A. A. Malygin ◽  
J. -M. Taulemesse ◽  
P. Gaudon ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Free Charge Carrier ◽  
Free Charge
Sign in / Sign up

Export Citation Format

Share Document