APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

5 Nov 2001

Volume 79, Issue 19, pp. 3017-3198

Return to All Sections
back to top
RSS Feeds

Fingerprints of two distinct defects causing light-induced photoconductivity degradation in hydrogenated amorphous silicon

Stephan Heck and Howard M. Branz

Appl. Phys. Lett. 79, 3080 (2001); http://dx.doi.org/10.1063/1.1413719 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We find distinct experimental fingerprints of two metastable defects created during illumination of hydrogenated amorphous silicon. The well-studied threefold-coordinated silicon dangling bond defect has an anneal activation energy near 1.1 eV and dominates annealing experiments above about 110 °C. The second defect created by illumination is the “primary recombination” (pr) center, which causes most of the light-induced photoconductivity decrease and dominates annealing experiments below about 110 °C. Because the pr centers are created in linear proportion to the dangling bond defects, they are difficult to distinguish during degradation. However, we observe clear fingerprints of the pr center during their low T annealing: (1) an anneal activation energy of 0.85 eV; (2) a sharp increase in photoconductivity; and (3) a surprising increase in hν ⩽ 1.1 eV optical absorption. © 2001 American Institute of Physics.
Show PACS
73.50.Pz Photoconduction and photovoltaic effects
71.55.Jv Disordered structures; amorphous and glassy solids
73.61.Jc Amorphous semiconductors; glasses
61.43.Dq Amorphous semiconductors, metals, and alloys
73.61.Cw Elemental semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Growth of well-aligned carbon nanotube arrays on silicon substrates using porous alumina film as a nanotemplate

Wenchong Hu, Dawei Gong, Zhi Chen, Liming Yuan, Kozo Saito, Craig A. Grimes, and Padmakar Kichambare

Appl. Phys. Lett. 79, 3083 (2001); http://dx.doi.org/10.1063/1.1415406 (3 pages) | Cited 52 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Aligned, open-tipped carbon nanotube arrays of high density and uniformity were synthesized via a flame method on silicon substrates using a nanoporous template of anodized aluminum oxide from which the nanotubes were grown. The diameter and length of the nanotubes are controlled by the geometry of the aluminum oxide template. These results show the feasibility of integration between carbon nanotube arrays and silicon microelectronics. © 2001 American Institute of Physics.
Show PACS
61.46.-w Structure of nanoscale materials
81.07.De Nanotubes
85.35.Kt Nanotube devices
81.16.Be Chemical synthesis methods
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology

Carrier density imaging of lateral epitaxially overgrown GaN using scanning confocal Raman microscopy

Manyalibo J. Matthews, J. W. P. Hsu, Shulin Gu, and T. F. Kuech

Appl. Phys. Lett. 79, 3086 (2001); http://dx.doi.org/10.1063/1.1415421 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
GaN thin films, grown by the lateral epitaxial overgrowth (LEO) method, are studied by scanning confocal Raman microscopy. By measuring changes in coupled longitudinal-optical phonon–plasmon frequencies and using a standard harmonic oscillator dielectric function, detailed images of carrier density could be formed. Carrier concentrations are extremely high ( ∼ 1020 cm−3) immediately above SiOx mask layers and decrease abruptly when the SiOx mask are not directly exposed to the growth surface, implying that SiOx masks are the source of dopants. Images of intergrated E1 longitudinal-optical phonon intensities could be compared with free-carrier images and showed a clear anticorrelation throughout the LEO structure.© 2001 American Institute of Physics.
Show PACS
78.66.Fd III-V semiconductors
78.30.Fs III-V and II-VI semiconductors
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
73.61.Ey III-V semiconductors
81.05.Ea III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
63.20.kk Phonon interactions with other quasiparticles

Formation of nonradiative defects in molecular beam epitaxial GaNxAs1−x studied by optically detected magnetic resonance

N. Q. Thinh, I. A. Buyanova, W. M. Chen, H. P. Xin, and C. W. Tu

Appl. Phys. Lett. 79, 3089 (2001); http://dx.doi.org/10.1063/1.1416155 (3 pages) | Cited 36 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The formation of two nonradiative defects (i.e., an AsGa-related complex and an unknown deep-level defect with g = 2.03) in GaNxAs1−x epilayers and GaAs/GaNxAs1−x multiple-quantum-well structures, grown by molecular beam epitaxy, is studied by the optically detected magnetic resonance technique. It is shown that contributions by these defects in competing carrier recombination strongly vary with the nitrogen composition. An increase in the growth temperature or postgrowth rapid thermal annealing significantly reduces the influence of the nonradiative defects studied, and is accompanied by a remarkable improvement in the optical properties of the structures. © 2001 American Institute of Physics.
Show PACS
76.70.Hb Optically detected magnetic resonance (ODMR)
73.20.Hb Impurity and defect levels; energy states of adsorbed species
71.55.Eq III-V semiconductors
73.21.Fg Quantum wells
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.72.Cc Kinetics of defect formation and annealing
61.82.Fk Semiconductors

On the interface states generated under different stress conditions

W. D. Zhang, J. F. Zhang, M. J. Uren, G. Groeseneken, R. Degraeve, M. Lalor, and D. Burton

Appl. Phys. Lett. 79, 3092 (2001); http://dx.doi.org/10.1063/1.1416168 (3 pages) | Cited 8 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
After dry oxidation and when annealing in a hydrogen environment is carefully avoided, the energy distribution of interface states has two peaks, one in the lower and one in the upper half of the silicon band gap. Following hydrogen passivation, however, the interface states created by irradiation or electron injection typically have only one peak in the upper half of the gap. This letter investigates how to generate a double peak distribution by electrical stress and we attempt to link the distribution with the generation mechanism. © 2001 American Institute of Physics.
Show PACS
85.30.Tv Field effect devices
73.20.At Surface states, band structure, electron density of states
81.65.Mq Oxidation

Carbon acceptor doping efficiency in GaAs grown by metalorganic chemical vapor deposition

J. Mimila-Arroyo, A. Lusson, J. Chevallier, M. Barbé, B. Theys, F. Jomard, and S. W. Bland

Appl. Phys. Lett. 79, 3095 (2001); http://dx.doi.org/10.1063/1.1413718 (3 pages) | Cited 5 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Carbon doping efficiency in GaAs grown by metalorganic chemical vapor deposition using intrinsic and extrinsic doping sources is studied. Independent of the carbon source, carbon hydrogen complexes are systematically present and depending on the growth conditions, carbon dimers can be present and form complexes with hydrogen as well. Carbon–hydrogen related complexes and dimers reduce the hole concentration decreasing the doping efficiency. Additionally, the carbon dimer introduces a deep level, decreases the hole mobility and hydrogen bonds stronger to it than to isolated carbon. Depending on the growth conditions it is possible to reach 100% doping efficiency with high hole mobility. © 2001 American Institute of Physics.
Show PACS
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.uj III-V and II-VI semiconductors
71.55.Eq III-V semiconductors
81.05.Ea III-V semiconductors
73.61.Ey III-V semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
73.50.Dn Low-field transport and mobility; piezoresistance

Quantifying electrical spin injection: Component-resolved electroluminescence from spin-polarized light-emitting diodes

B. T. Jonker, A. T. Hanbicki, Y. D. Park, G. Itskos, M. Furis, G. Kioseoglou, A. Petrou, and X. Wei

Appl. Phys. Lett. 79, 3098 (2001); http://dx.doi.org/10.1063/1.1416164 (3 pages) | Cited 40 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The spin-polarized light-emitting diode (spin-LED) is a very effective tool for accurately quantifying electrical spin injection in a model independent manner. We resolve and identify various components which occur in the electroluminescence (EL) spectra of GaAs quantum-well-based spin-LEDs, and examine the circular polarization of each. While a number of components exhibit significant circular polarization, the values do not necessarily reflect the electrical spin injection efficiency. We show that a reliable measure of spin injection efficiency can be obtained only if one takes care to spectroscopically resolve and accurately identify the free exciton or free carrier components of the EL spectrum, and exclude other components. © 2001 American Institute of Physics.
Show PACS
75.50.Pp Magnetic semiconductors
85.60.Jb Light-emitting devices
78.60.Fi Electroluminescence
85.75.-d Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close