Inhomogeneous distribution of defect-related emission in Si-doped AlGaN epitaxial layers with different Al content and Si concentration

AbstractThe electrical and photoluminescent properties of vanadium incorporated into GaAs epitaxial layers from a VO(OC2 H5)3 source during organometallic vapor phase epitaxy were examined. The vanadium concentration in the GaAs was controllably varied from 1016 to 1018 atoms cm−3. Deep level transient spectroscopy showed the presence of an electron trap at Ec – 0.15 eV which increased in concentration with vanadium content of the epitaxial layers. A maximum value of 8 × 1015 cm−3 for this trap was obtained. There were no midgap electron traps associated with vanadium. In intentionally Si-doped epitaxial layers, co-doping with vanadium was observed to have no effect in reducing the carrier density when the Si concentration was > 4 × 1016 cm−3. The net carrier concentration profiles resulting from 29 si implantation into GaAs containing 1018 cm−3of total V had sharper tails than for similar implantation into undoped material, indicating the presence of less than 1016 cm−3V-related acceptors. Photoluminescent spectra exhibited the characteristic V+3intracenter emission at 0.65∼0.75 eV. No other deep level photoluminescence was detected. For a V concentration of 1016 cm−3only 2.5 × 1013 cm−3was electrically active. Over the entire V concentration investigated this impurity was predominantly (≥99%) inactive.

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Midgap electron traps in n-type GaAs epitaxial layers grown by the close-spaced vapor transport technique

Canadian Journal of Physics ◽

10.1139/p91-066 ◽

1991 ◽

Vol 69 (3-4) ◽

pp. 407-411 ◽

Cited By ~ 2

Author(s):

T. Bretagnon ◽

A. Jean ◽

P. Silvestre ◽

S. Bourassa ◽

R. Le Van Mao ◽

...

Keyword(s):

Deep Level Transient Spectroscopy ◽

Emission Rate ◽

Deep Level ◽

Vapor Transport ◽

Epitaxial Layers ◽

Spectroscopy Technique ◽

Electron Traps ◽

Si Doped ◽

Transient Spectroscopy ◽

Transport Technique

The deep-level transient spectroscopy technique was applied to the study of deep electron traps existing in n-type GaAs epitaxial layers that were prepared by the close-spaced vapor transport technique using three kinds of sources (semi-insulator-undoped, Zn-doped and Si-doped GaAs). Two midgap electron traps labelled ELCS1 and EL2 were observed in all layers regardless of the kind of source used. In addition, the effect of the electric field on the emission rate of ELCS1 is discussed and its identification to ETX2 and EL12 is suggested.

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Development of AlAsSb as a barrier material for ultra-thin-channel InGaAs nMOSFETs

MRS Proceedings ◽

10.1557/opl.2013.821 ◽

2013 ◽

Vol 1561 ◽

Cited By ~ 2

Author(s):

Cheng-Ying Huang ◽

Jeremy J. M. Law ◽

Hong Lu ◽

Mark J. W. Rodwell ◽

Arthur C. Gossard

Keyword(s):

Molecular Beam Epitaxy ◽

Carrier Concentration ◽

Electron Mobility ◽

Molecular Beam ◽

Epitaxial Layers ◽

Barrier Material ◽

Double Heterostructures ◽

Thin Channel ◽

Si Doped ◽

Lattice Matched

ABSTRACTWe investigated AlAs0.56Sb0.44 epitaxial layers lattice-matched to InP grown by molecular beam epitaxy (MBE). Silicon (Si) and tellurium (Te) were studied as n-type dopants in AlAs0.56Sb0.44 material. Similar to most Sb-based materials, AlAs0.56Sb0.44 demonstrates a maximum active carrier concentration around low-1018 cm-3 when using Te as a dopant. We propose the use of a heavily Si-doped InAlAs layer embedded in the AlAsSb barrier as a modulation-doped layer. The In0.53Ga0.47As/AlAs0.56Sb0.44 double heterostructures with a 10 nm InGaAs well show an electron mobility of about 9400 cm2/V・s at 295 K and 32000 cm2/V・s at 46 K. A thinner 5 nm InGaAs well has an electron mobility of about 4300 cm2/V・s at 295 K. This study demonstrates that AlAs0.56Sb0.44 is a promising barrier material for highly scaled InGaAs MOSFETs and HEMTs.

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Influence of Al content on electrical and structural properties of Si-doped AlxGa1–xN/GaN HEMT structures

physica status solidi (c) ◽

10.1002/pssc.200564129 ◽

2006 ◽

Vol 3 (3) ◽

pp. 486-489 ◽

Cited By ~ 8

Author(s):

Cuimei Wang ◽

Xiaoliang Wang ◽

Guoxin Hu ◽

Junxi Wang ◽

Jianping Li

Keyword(s):

Structural Properties ◽

Al Content ◽

Gan Hemt ◽

Si Doped

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X-Ray DCD and EPMA Measurements of Al Concentration in Epitaxial AlxGa1-xAs/GaAs Layers

Advances in X-ray Analysis ◽

10.1154/s0376030800018826 ◽

1992 ◽

Vol 36 ◽

pp. 221-229

Author(s):

D.A. Macquistan ◽

I.C. Bassignana ◽

A.J. SpringThorpe ◽

R. Packwood ◽

V. Moore

Keyword(s):

Epitaxial Layers ◽

X Ray Diffraction ◽

Double Crystal ◽

X Ray ◽

Al Content ◽

The Relationship ◽

Composition Measurements

AbstractDouble Crystal X-Ray Diffraction (DCD) is often used to determine the Al content of AlxGa1-xAs/GaAs epitaxial layers. Assessing composition from a measurement of mismatch is problematic because it invokes a number of assumptions. This study bypasses these difficulties by comparing the measurement of mismatch directly with Al composition measurements made by electronprobe microanalysis. A study of coherent epitaxial AlxGa1-xAs layers showed that mismatch varies linearly with composition. The equation Al (x) = |ΔΘ| / 368 summarizes the relationship over the coherent range, where |ΔΘ| is measured in arc seconds.

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OMVPE growth of undoped and Si-doped GaAs epitaxial layers on Ge

Journal of Crystal Growth ◽

10.1016/s0022-0248(98)00600-9 ◽

1998 ◽

Vol 193 (4) ◽

pp. 501-509 ◽

Cited By ~ 13

Author(s):

Prasanta Modak ◽

Mantu Kumar Hudait ◽

Shyam Hardikar ◽

S.B Krupanidhi

Keyword(s):

Epitaxial Layers ◽

Si Doped

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The Effect of Substrate Orientation on the Properties of (Ga, Al)As Grown by Gas Source Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-144-215 ◽

1988 ◽

Vol 144 ◽

Author(s):

A. Sandhu ◽

T. FUJII ◽

H. Ando ◽

H. Ishikawa ◽

E. Miyauchi

Keyword(s):

Growth Rate ◽

Growth Conditions ◽

Group V ◽

Group Iii ◽

Al Content ◽

Gas Source ◽

Compensation Ratio ◽

Potential Applications ◽

Si Doped ◽

Gas Source Mbe

ABSTRACTWe have carried out the first systemmatic investigation on the effect of substrate temperature and arsenic partial pressure on the morphology, growth rate, and compensation ratio of Si-doped GaAs, and the Al content of AlxGa1−xAs grown on just-cut (100), (110), (111)A&B, (311)A&B orientated GaAs substrates by gas source MBE (GSMBE). Triethylgallium ( TEG, Ga(C2H5)3 ) and triethylaluminium ( TEA, Al(C2H5)3 ) were used as group III sources, and solid arsenic ( As4 ) and silicon as a group V and IV sources, respectively. The best GaAs mophology was obtained at relatively high temperatures and arsenic pressures. The A orientations were identified as ‘fast surfaces,’ with the GaAs growth rate being comparable to the (100) orientation. The B orientations were identified as ‘slow surfaces,’ with the GaAs growth rate being much less (approximately 50% for the (111)B orientation ) than on the (100) orientation. The least compensated Si-doped GaAs was grown on the (311)A orientated substrate. The Al content, x, (nominally x=0.27 for (100)) of AlxGas1−xAs grown on (110), (111)A&B, was less than 0.05 and not affected by the growth conditions. The Al content of epilayers grown on (311)A&B ranged between x=0.1 to 0.27, strongly depending on the growth temperature.These results show that using GSMBE we can selectively modifying a large range of (Ga,Al)As crystal properties. Potential applications include the selective growth and realisation of ultra-fine and planar structures and devices.

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