Infrared reflectance analysis of GaN epitaxial layers grown on sapphire and silicon substrates

Z. C. Feng, T. R. Yang, Y. T. Hou

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Infrared reflectance (IR) of GaN grown on sapphire and silicon substrates has been studied both theoretically and experimentally. The theoretical calculation of the IR spectra is based on the transfer matrix method. The IR spectral characteristics influenced by several factors, such as film thickness, incident angle, free carriers, are systematically examined. Combined with experimental results, surface scattering and interface layer effects are also studied. For GaN epilayers grown on sapphire, carrier concentrations and mobility are determined by fitting to the IR reststrahlen band and compared with the Hall measurement. The interface effect is demonstrated to cause a damping behaviour of the interference fringes away from the reststrahlen band. For GaN grown on Si, the IR spectra predicted the large surface roughness of the epilayers. A variation of IR reststrahlen band is correlated to the microstructures of the films, i.e. their polycrystalline nature of the GaN films grown on Si. A three-component effective medium model is proposed to calculate the IR spectra for polycrystalline GaN, and a qualitative correlation between the IR spectra and structure of the film is established. All results show that IR, as a non-destructive method, is efficient for characterising GaN epilayers in semiconductor processing.

Original languageEnglish
Pages (from-to)571-576
Number of pages6
JournalMaterials Science in Semiconductor Processing
Volume4
Issue number6
DOIs
Publication statusPublished - 2001 Dec 1

Fingerprint

Aluminum Oxide
Epitaxial layers
Silicon
Sapphire
sapphire
Infrared radiation
reflectance
silicon
Substrates
Epilayers
spectral reflectance
Surface scattering
Transfer matrix method
Carrier mobility
matrix methods
surface roughness
film thickness
Carrier concentration
Film thickness
damping

Keywords

  • GaN
  • Infrared reflectance
  • Non-destructive
  • Sapphire
  • Silicon

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials

Cite this

Infrared reflectance analysis of GaN epitaxial layers grown on sapphire and silicon substrates. / Feng, Z. C.; Yang, T. R.; Hou, Y. T.

In: Materials Science in Semiconductor Processing, Vol. 4, No. 6, 01.12.2001, p. 571-576.

Research output: Contribution to journalArticle

@article{138be095f66d4c97b3522751ee5a9fd1,
title = "Infrared reflectance analysis of GaN epitaxial layers grown on sapphire and silicon substrates",
abstract = "Infrared reflectance (IR) of GaN grown on sapphire and silicon substrates has been studied both theoretically and experimentally. The theoretical calculation of the IR spectra is based on the transfer matrix method. The IR spectral characteristics influenced by several factors, such as film thickness, incident angle, free carriers, are systematically examined. Combined with experimental results, surface scattering and interface layer effects are also studied. For GaN epilayers grown on sapphire, carrier concentrations and mobility are determined by fitting to the IR reststrahlen band and compared with the Hall measurement. The interface effect is demonstrated to cause a damping behaviour of the interference fringes away from the reststrahlen band. For GaN grown on Si, the IR spectra predicted the large surface roughness of the epilayers. A variation of IR reststrahlen band is correlated to the microstructures of the films, i.e. their polycrystalline nature of the GaN films grown on Si. A three-component effective medium model is proposed to calculate the IR spectra for polycrystalline GaN, and a qualitative correlation between the IR spectra and structure of the film is established. All results show that IR, as a non-destructive method, is efficient for characterising GaN epilayers in semiconductor processing.",
keywords = "GaN, Infrared reflectance, Non-destructive, Sapphire, Silicon",
author = "Feng, {Z. C.} and Yang, {T. R.} and Hou, {Y. T.}",
year = "2001",
month = "12",
day = "1",
doi = "10.1016/S1369-8001(02)00020-3",
language = "English",
volume = "4",
pages = "571--576",
journal = "Materials Science in Semiconductor Processing",
issn = "1369-8001",
publisher = "Elsevier Limited",
number = "6",

}

TY - JOUR

T1 - Infrared reflectance analysis of GaN epitaxial layers grown on sapphire and silicon substrates

AU - Feng, Z. C.

AU - Yang, T. R.

AU - Hou, Y. T.

PY - 2001/12/1

Y1 - 2001/12/1

N2 - Infrared reflectance (IR) of GaN grown on sapphire and silicon substrates has been studied both theoretically and experimentally. The theoretical calculation of the IR spectra is based on the transfer matrix method. The IR spectral characteristics influenced by several factors, such as film thickness, incident angle, free carriers, are systematically examined. Combined with experimental results, surface scattering and interface layer effects are also studied. For GaN epilayers grown on sapphire, carrier concentrations and mobility are determined by fitting to the IR reststrahlen band and compared with the Hall measurement. The interface effect is demonstrated to cause a damping behaviour of the interference fringes away from the reststrahlen band. For GaN grown on Si, the IR spectra predicted the large surface roughness of the epilayers. A variation of IR reststrahlen band is correlated to the microstructures of the films, i.e. their polycrystalline nature of the GaN films grown on Si. A three-component effective medium model is proposed to calculate the IR spectra for polycrystalline GaN, and a qualitative correlation between the IR spectra and structure of the film is established. All results show that IR, as a non-destructive method, is efficient for characterising GaN epilayers in semiconductor processing.

AB - Infrared reflectance (IR) of GaN grown on sapphire and silicon substrates has been studied both theoretically and experimentally. The theoretical calculation of the IR spectra is based on the transfer matrix method. The IR spectral characteristics influenced by several factors, such as film thickness, incident angle, free carriers, are systematically examined. Combined with experimental results, surface scattering and interface layer effects are also studied. For GaN epilayers grown on sapphire, carrier concentrations and mobility are determined by fitting to the IR reststrahlen band and compared with the Hall measurement. The interface effect is demonstrated to cause a damping behaviour of the interference fringes away from the reststrahlen band. For GaN grown on Si, the IR spectra predicted the large surface roughness of the epilayers. A variation of IR reststrahlen band is correlated to the microstructures of the films, i.e. their polycrystalline nature of the GaN films grown on Si. A three-component effective medium model is proposed to calculate the IR spectra for polycrystalline GaN, and a qualitative correlation between the IR spectra and structure of the film is established. All results show that IR, as a non-destructive method, is efficient for characterising GaN epilayers in semiconductor processing.

KW - GaN

KW - Infrared reflectance

KW - Non-destructive

KW - Sapphire

KW - Silicon

UR - http://www.scopus.com/inward/record.url?scp=0035574701&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035574701&partnerID=8YFLogxK

U2 - 10.1016/S1369-8001(02)00020-3

DO - 10.1016/S1369-8001(02)00020-3

M3 - Article

AN - SCOPUS:0035574701

VL - 4

SP - 571

EP - 576

JO - Materials Science in Semiconductor Processing

JF - Materials Science in Semiconductor Processing

SN - 1369-8001

IS - 6

ER -