Physical Properties of Silicon Doped Hetero-Epitaxial MOCVD Grown GaN: Influence of Doping Level and Stress

AbstractSilicon doped layers GaN were grown with MOCVD on sapphire substrates using silane as silicon precursor. The influence of the silicon doping concentration on the physical and optical properties is investigated. A linear relationship is found between the silane-input molfraction and the free carrier concentration in the GaN layers. The morphology of the samples is drastically changed at high silicon concentrations. Photoluminescence was used to probe bandgap variations as function of the silicon concentration. Increasing of the doping concentration led to a continuous shift of the exciton related PL to lower energies, while the intensity of the UV emission was found to increase up to a carrier concentration of n=2.5×1018 cm−3.

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Mapping of Donor Impurities in Gan By Raman Imaging

MRS Proceedings ◽

10.1557/proc-449-731 ◽

1996 ◽

Vol 449 ◽

Cited By ~ 1

Author(s):

F. A. Ponce ◽

J. W. Steeds ◽

C. D. Dyer ◽

G. D. Pitt

Keyword(s):

Raman Scattering ◽

Spatial Variation ◽

Carrier Concentration ◽

Raman Line ◽

Free Carrier ◽

Raman Imaging ◽

Free Carrier Concentration ◽

Lattice Vibrations ◽

Silicon Doped ◽

Preferential Incorporation

ABSTRACTRaman scattering experiments on silicon-doped GaN show that donor impurities quench the Al(LO) Raman line at 735 cm−1. This is due to interaction between lattice vibrations and the free carrier plasma. The spatial variation of the Al(LO) signal has been imaged directly using newly developed instrumentation. Features with dimension under on micron are observed in faceted GaN crystallites. The variation in free carrier concentration is attributed to preferential incorporation of donor impurities during growth.

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On Compensation and Impurities in State-of-the-Art GaN Epilayers Grown on Sapphire

MRS Proceedings ◽

10.1557/proc-395-679 ◽

1995 ◽

Vol 395 ◽

Cited By ~ 24

Author(s):

A.E. Wickenden ◽

D.K. Gaskill ◽

D.D. Koleske ◽

K. Doverspike ◽

D.S. Simons ◽

...

Keyword(s):

Activation Energy ◽

Electron Transport ◽

State Of The Art ◽

Theoretical Calculations ◽

Recent Analysis ◽

Silicon Doping ◽

Sapphire Substrates ◽

Silicon Doped ◽

Gan Film

ABSTRACTA comparison between 300 K electron transport data for state-of-the-art wurtzite GaN grown on sapphire substrates and corresponding theoretical calculations shows a large difference, with experimental mobility less than the predicted mobility for a given carrier concentration. The comparison seems to imply that GaN films are greatly compensated, but the discrepancy may also be due to the poorly known values of the materials parameters used in the calculations. In this work, recent analysis of transport and SIMS measurements on silicon-doped GaN films are shown to imply that the compensation, NA/ND, is less than 0.3. In addition, the determination of an activation energy of 34 meV in a GaN film doped to a level of 6×1016 cm−3 suggests either that a second, native donor exists in the doped films at a level of between 6×1017 cm−3 and 1×1017 cm−3, or that the activation energy of Si in GaN is dependent on the concentration, being influenced by impurity banding or some other physical effect. GaN films grown without silicon doping are highly resistive.

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Infrared Optical Properties of Ion Implanted and Laser Annealed Silicon

MRS Proceedings ◽

10.1557/proc-1-163 ◽

1980 ◽

Vol 1 ◽

Cited By ~ 2

Author(s):

Masanobu Miyao ◽

Teruaki Motooka ◽

Nobuyoshi Natsuaki ◽

Takashi Tokuyama

Keyword(s):

Optical Properties ◽

Carrier Concentration ◽

Laser Annealing ◽

Electronic States ◽

Free Carrier ◽

High Dose ◽

Carrier Relaxation ◽

Carrier Effective Mass ◽

Heavily Doped ◽

Infrared Optical Properties

ABSTRACTElectronic states of extremely heavily doped n-type Si obtained by high dose ion implantation and laser annealing are investigated by measuring the infrared optical properties. Free carrier effective mass (m*) and carrier relaxation time (τ) are obtained as a function of carrier concentration (1019−5×1021 cm−3). Values of m* and τ increase and decrease, respectively, with the increase of carrier concentration. These results are discussed in relation to the occupation of electrons in a new valley of the conduction band.

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The Growth and Optical Properties of Al-Doped ZnO Nanofibers Using PVP Nanofibers as Templates by Atom Layer Deposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.924.23 ◽

2014 ◽

Vol 924 ◽

pp. 23-28

Author(s):

Dan Fang ◽

Xuan Fang ◽

Hai Feng Zhao ◽

Shuang Li ◽

Zhi Peng Wei ◽

...

Keyword(s):

Optical Properties ◽

Doping Concentration ◽

Stress Generation ◽

X Ray Diffraction ◽

Al Doping ◽

Uv Emission ◽

Layer Deposition ◽

Zno Nanofibers ◽

Doped Zno ◽

Atom Layer

Different doping concentration Al-doped ZnO nanofibers were synthesized by Atom Layer Deposition (ALD) using PVP fibers as template. The influence of Al doping concentration on the structure and optical properties of nanofibers was investigated. The samples were characterized by means of X-ray diffraction spectra, field emission scanning electron microscopy (FESEM). After doping, the morphologies were not changed, only the diameters of Al-doped ZnO nanofibers became larger. Compared with undoped ZnO, the intensity of diffractive peaks of Al-doped ZnO nanofibers became weak with the increasing of the doping concentration due to stress generation in the crystallization process. In raman spectra, Al2O3peak related peaks were also observed. In addition, the intensity of UV emission decreased with increasing Al doping concentration and had a red shift.

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