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Electronic Properties of Group-III Nitride Semiconductors and Device Structures Probed by THz Optical Hall Effect

Armakavicius, Nerijus ; Kühne, Philipp ; Papamichail, Alexis ; Zhang, Hengfang ; Knight, Sean LU ; Persson, Axel ; Stanishev, Vallery ; Chen, Jr Tai ; Paskov, Plamen and Schubert, Mathias LU orcid , et al. (2024) In Materials 17(13).
Abstract

Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This non-destructive technique employs spectroscopic ellipsometry at long... (More)

Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This non-destructive technique employs spectroscopic ellipsometry at long wavelengths in the presence of a magnetic field and provides quantitative information on the charge carrier density, sign, mobility, and effective mass of individual layers in multilayer structures and bulk materials. In this paper, we explore the use of terahertz (THz) OHE to study the charge carrier properties in group-III nitride heterostructures and bulk material. Examples include graded AlGaN channel high-electron-mobility transistor (HEMT) structures for high-linearity devices, highlighting the different grading profiles and their impact on the two-dimensional electron gas (2DEG) properties. Next, we demonstrate the sensitivity of the THz OHE to distinguish the 2DEG anisotropic mobility parameters in N-polar GaN/AlGaN HEMTs and show that this anisotropy is induced by the step-like surface morphology. Finally, we present the temperature-dependent results on the charge carrier properties of 2DEG and bulk electrons in GaN with a focus on the effective mass parameter and review the effective mass parameters reported in the literature. These studies showcase the capabilities of the THz OHE for advancing the understanding and development of group-III materials and devices.

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organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
aluminum gallium nitride, aluminum nitride, electrical properties, free charge carriers, gallium nitride, group-III nitrides, HEMT, high-electron-mobility transistor, optical Hall effect, terahertz
in
Materials
volume
17
issue
13
article number
3343
publisher
MDPI AG
external identifiers
  • scopus:85198382119
ISSN
1996-1944
DOI
10.3390/ma17133343
language
English
LU publication?
yes
id
eefcf85e-145a-4296-8b37-275802cc4a63
date added to LUP
2024-09-30 14:53:00
date last changed
2024-09-30 14:53:50
@article{eefcf85e-145a-4296-8b37-275802cc4a63,
  abstract     = {{<p>Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This non-destructive technique employs spectroscopic ellipsometry at long wavelengths in the presence of a magnetic field and provides quantitative information on the charge carrier density, sign, mobility, and effective mass of individual layers in multilayer structures and bulk materials. In this paper, we explore the use of terahertz (THz) OHE to study the charge carrier properties in group-III nitride heterostructures and bulk material. Examples include graded AlGaN channel high-electron-mobility transistor (HEMT) structures for high-linearity devices, highlighting the different grading profiles and their impact on the two-dimensional electron gas (2DEG) properties. Next, we demonstrate the sensitivity of the THz OHE to distinguish the 2DEG anisotropic mobility parameters in N-polar GaN/AlGaN HEMTs and show that this anisotropy is induced by the step-like surface morphology. Finally, we present the temperature-dependent results on the charge carrier properties of 2DEG and bulk electrons in GaN with a focus on the effective mass parameter and review the effective mass parameters reported in the literature. These studies showcase the capabilities of the THz OHE for advancing the understanding and development of group-III materials and devices.</p>}},
  author       = {{Armakavicius, Nerijus and Kühne, Philipp and Papamichail, Alexis and Zhang, Hengfang and Knight, Sean and Persson, Axel and Stanishev, Vallery and Chen, Jr Tai and Paskov, Plamen and Schubert, Mathias and Darakchieva, Vanya}},
  issn         = {{1996-1944}},
  keywords     = {{aluminum gallium nitride; aluminum nitride; electrical properties; free charge carriers; gallium nitride; group-III nitrides; HEMT; high-electron-mobility transistor; optical Hall effect; terahertz}},
  language     = {{eng}},
  number       = {{13}},
  publisher    = {{MDPI AG}},
  series       = {{Materials}},
  title        = {{Electronic Properties of Group-III Nitride Semiconductors and Device Structures Probed by THz Optical Hall Effect}},
  url          = {{http://dx.doi.org/10.3390/ma17133343}},
  doi          = {{10.3390/ma17133343}},
  volume       = {{17}},
  year         = {{2024}},
}