Capacitance voltage characteristics and electron holography on cubic AlGaN/GaN heterojunctions

Donat J. As, Alexander Zado, Qiyang Y. Wei, Ti Li, Jingyi Y. Huang, Fernando Ponce

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Cubic AlxGa1-xN/GaN heterostructures were grown by plasma-assisted molecular beam epitaxy on free-standing 3C-SiC(001). The samples consist of an unintentionally doped 600nm thick c-GaN buffer and a 30 nm c-Al0.3Ga0.7N layer. Capacitance-voltage measurements were performed on metal-oxide-semiconductor heterojunction structure using SiO 2 as an insulator. A depth profile of the net donor concentration NCV of the grown sample was measured, demonstrating a clear carrier accumulation at the heterojunction. By electron holography in a transmission electron microscope the potential profile was measured and a free electron concentration of 5.1 × 1011 cm-2 was estimated at the c-Al xGa1-xN/ GaN interface. Using a one-dimensional (1D) Poisson simulator the results of both techniques are compared and a conduction-to-valence band offset ratio of about 4 : 1 for the cubic Al xGa1-xN/GaN interface is estimated, which promotes the electron accumulation. Our results demonstrate that the two-dimensional electron gas (2DEG) in cubic AlxGa1-xN/GaN heterostructures can be achieved without the need of polarization effects and is due to the residual background doping in the AlxGa1-xN and GaN.

Original languageEnglish (US)
Article number08JN04
JournalJapanese Journal of Applied Physics
Volume52
Issue number8 PART 2
DOIs
StatePublished - Aug 2013

Fingerprint

Electron holography
capacitance-voltage characteristics
holography
Heterojunctions
heterojunctions
Capacitance
Two dimensional electron gas
Electric potential
profiles
metal oxide semiconductors
electrical measurement
free electrons
simulators
electron gas
electrons
molecular beam epitaxy
buffers
electron microscopes
capacitance
insulators

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Capacitance voltage characteristics and electron holography on cubic AlGaN/GaN heterojunctions. / As, Donat J.; Zado, Alexander; Wei, Qiyang Y.; Li, Ti; Huang, Jingyi Y.; Ponce, Fernando.

In: Japanese Journal of Applied Physics, Vol. 52, No. 8 PART 2, 08JN04, 08.2013.

Research output: Contribution to journalArticle

As, Donat J. ; Zado, Alexander ; Wei, Qiyang Y. ; Li, Ti ; Huang, Jingyi Y. ; Ponce, Fernando. / Capacitance voltage characteristics and electron holography on cubic AlGaN/GaN heterojunctions. In: Japanese Journal of Applied Physics. 2013 ; Vol. 52, No. 8 PART 2.
@article{0ca40d50d2ce4d1b86244a4de85d81db,
title = "Capacitance voltage characteristics and electron holography on cubic AlGaN/GaN heterojunctions",
abstract = "Cubic AlxGa1-xN/GaN heterostructures were grown by plasma-assisted molecular beam epitaxy on free-standing 3C-SiC(001). The samples consist of an unintentionally doped 600nm thick c-GaN buffer and a 30 nm c-Al0.3Ga0.7N layer. Capacitance-voltage measurements were performed on metal-oxide-semiconductor heterojunction structure using SiO 2 as an insulator. A depth profile of the net donor concentration NCV of the grown sample was measured, demonstrating a clear carrier accumulation at the heterojunction. By electron holography in a transmission electron microscope the potential profile was measured and a free electron concentration of 5.1 × 1011 cm-2 was estimated at the c-Al xGa1-xN/ GaN interface. Using a one-dimensional (1D) Poisson simulator the results of both techniques are compared and a conduction-to-valence band offset ratio of about 4 : 1 for the cubic Al xGa1-xN/GaN interface is estimated, which promotes the electron accumulation. Our results demonstrate that the two-dimensional electron gas (2DEG) in cubic AlxGa1-xN/GaN heterostructures can be achieved without the need of polarization effects and is due to the residual background doping in the AlxGa1-xN and GaN.",
author = "As, {Donat J.} and Alexander Zado and Wei, {Qiyang Y.} and Ti Li and Huang, {Jingyi Y.} and Fernando Ponce",
year = "2013",
month = "8",
doi = "10.7567/JJAP.52.08JN04",
language = "English (US)",
volume = "52",
journal = "Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes",
issn = "0021-4922",
publisher = "Japan Society of Applied Physics",
number = "8 PART 2",

}

TY - JOUR

T1 - Capacitance voltage characteristics and electron holography on cubic AlGaN/GaN heterojunctions

AU - As, Donat J.

AU - Zado, Alexander

AU - Wei, Qiyang Y.

AU - Li, Ti

AU - Huang, Jingyi Y.

AU - Ponce, Fernando

PY - 2013/8

Y1 - 2013/8

N2 - Cubic AlxGa1-xN/GaN heterostructures were grown by plasma-assisted molecular beam epitaxy on free-standing 3C-SiC(001). The samples consist of an unintentionally doped 600nm thick c-GaN buffer and a 30 nm c-Al0.3Ga0.7N layer. Capacitance-voltage measurements were performed on metal-oxide-semiconductor heterojunction structure using SiO 2 as an insulator. A depth profile of the net donor concentration NCV of the grown sample was measured, demonstrating a clear carrier accumulation at the heterojunction. By electron holography in a transmission electron microscope the potential profile was measured and a free electron concentration of 5.1 × 1011 cm-2 was estimated at the c-Al xGa1-xN/ GaN interface. Using a one-dimensional (1D) Poisson simulator the results of both techniques are compared and a conduction-to-valence band offset ratio of about 4 : 1 for the cubic Al xGa1-xN/GaN interface is estimated, which promotes the electron accumulation. Our results demonstrate that the two-dimensional electron gas (2DEG) in cubic AlxGa1-xN/GaN heterostructures can be achieved without the need of polarization effects and is due to the residual background doping in the AlxGa1-xN and GaN.

AB - Cubic AlxGa1-xN/GaN heterostructures were grown by plasma-assisted molecular beam epitaxy on free-standing 3C-SiC(001). The samples consist of an unintentionally doped 600nm thick c-GaN buffer and a 30 nm c-Al0.3Ga0.7N layer. Capacitance-voltage measurements were performed on metal-oxide-semiconductor heterojunction structure using SiO 2 as an insulator. A depth profile of the net donor concentration NCV of the grown sample was measured, demonstrating a clear carrier accumulation at the heterojunction. By electron holography in a transmission electron microscope the potential profile was measured and a free electron concentration of 5.1 × 1011 cm-2 was estimated at the c-Al xGa1-xN/ GaN interface. Using a one-dimensional (1D) Poisson simulator the results of both techniques are compared and a conduction-to-valence band offset ratio of about 4 : 1 for the cubic Al xGa1-xN/GaN interface is estimated, which promotes the electron accumulation. Our results demonstrate that the two-dimensional electron gas (2DEG) in cubic AlxGa1-xN/GaN heterostructures can be achieved without the need of polarization effects and is due to the residual background doping in the AlxGa1-xN and GaN.

UR - http://www.scopus.com/inward/record.url?scp=84883145898&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84883145898&partnerID=8YFLogxK

U2 - 10.7567/JJAP.52.08JN04

DO - 10.7567/JJAP.52.08JN04

M3 - Article

VL - 52

JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

SN - 0021-4922

IS - 8 PART 2

M1 - 08JN04

ER -