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PHYSICS OF SEMICONDUCTORS: 29th International Conference on the Physics of Semiconductors Date: 27 July–1 August 2009 Location: Rio de Janeiro (Brazil) ISBN: 978-0-7354-0736-7 Editor(s): Marília Caldas, Nelson Studart

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Surface compositional profiles of self‐assembled InAs∕GaAs quantum rings

Rita Magri, Stefan Heun, Giorgio Biasiol, Andrea Locatelli, Tevfik O. Mentes, and Lucia Sorba

AIP Conf. Proc. 1199, pp. 3-4; doi:http://dx.doi.org/10.1063/1.3295472 (2 pages)

Online Publication Date: 15 January 2010

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The surface composition profiles of self‐assembled InAs∕GaAs quantum rings (QR) are studied both experimentally and theoretically. By using X‐ray Photoemission Electron Microscopy (XPEEM) we obtain a 2D composition mapping of unburied rings, which can be directly related to the QR topography measured by Atomic Force Microscopy (AFM). Top‐surface composition mapping allows us to obtain information on structures which cannot be directly accessed with cross‐sectional studies since overgrowing the QRs with a thick GaAs film alters both their morphology and composition. The 2D surface maps reveal a non‐uniform distribution across the rings with an In richer InGaAs alloy in the central hole regions. Elastic energy calculations via a Valence Force Field (VFF) approach show that, for a given shape of the rings and a fixed total number of Ga and In atoms, an In enrichment of the alloy in the central hole region, together with an In enrichment of the surface layers, leads to a lowering of the total strain energy.
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81.07.Bc Nanocrystalline materials
82.80.Pv Electron spectroscopy (X-ray photoelectron (XPS), Auger electron spectroscopy (AES), etc.)
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.37.Lp Transmission electron microscopy (TEM)
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Atomically precise Si(331)‐(12×1) surfaces

Corsin Battaglia, Claude Monney, Clément Didiot, Eike Fabian Schwier, Nicolas Mariotti, Michael Gunnar Garnier, and Philipp Aebi

AIP Conf. Proc. 1199, pp. 5-6; doi:http://dx.doi.org/10.1063/1.3295553 (2 pages)

Online Publication Date: 15 January 2010

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Si(331)‐(12×1) is the only confirmed planar silicon surface with a stable reconstruction located between (111) and (110). We have optimized the annealing sequence and are able to obtain almost defect free, atomically precise surface areas approaching micrometer dimensions. The unprecedented perfection of the surface combined with its pronounced structural anisotropy makes it a promising candidate to serve as template for the growth of self‐assembled one‐dimensional nanostructure arrays.
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73.63.Bd Nanocrystalline materials
68.47.Fg Semiconductor surfaces
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
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STRUCTURAL CHARACTERIZATION OF CdTe∕Si(111) QUANTUM DOTS

J. Suela, S. O. Ferreira, E. Abramof, I. R. B. Ribeiro, and A. Malachias

AIP Conf. Proc. 1199, pp. 7-8; doi:http://dx.doi.org/10.1063/1.3295563 (2 pages)

Online Publication Date: 15 January 2010

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We report on the structural characterization of ultra thin CdTe layers and quantum dots grown by Hot Wall Epitaxy on [111] oriented silicon substrates. Atomic Force Microscopy shows that this system follows the Volmer‐Weber growth mode, while specular and Grazing Incidence X‐ray Diffraction data reveal [111] oriented islands undertaken epitaxial growth even in despite of large lattice mismatch, of almost 20%. Measurements of (220) CdTe reflections in a PHI scan indicate an in‐plane 30° rotation of a small percentage of de islands regarding the substrate lattice.
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68.65.Hb Quantum dots (patterned in quantum wells)
68.37.Ps Atomic force microscopy (AFM)
61.05.cp X-ray diffraction
85.60.-q Optoelectronic devices
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A reaction pathway for water adsorption on Si(100)(2×1)

R. Lelis‐Sousa and M. J. Caldas

AIP Conf. Proc. 1199, pp. 9-10; doi:http://dx.doi.org/10.1063/1.3295573 (2 pages)

Online Publication Date: 15 January 2010

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We present ab initio investigations for the reaction pathway between gas phase water and the Si(100)(2×1) surface. The results indicate that there is no barrier for adsorption and that the mechanism of dissociation occurs by molecular physisorption. However, the chemisorption process is very favorable (by ΔE  =  −2.14 eV) and the barrier is very small (ΔE  =  +0.01 eV). We show that the oxygen attack is efficient from any position of water colliding with the surface dimer, and that the interaction between the molecule and the surface begins earlier than estimated previously.
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68.43.Bc Ab initio calculations of adsorbate structure and reactions
68.43.Mn Adsorption kinetics
31.15.B- Approximate calculations
71.15.Dx Computational methodology (Brillouin zone sampling, iterative diagonalization, pseudopotential construction)
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Vapor‐Liquid‐Solid Synthesis of Ge Nanowire on H‐terminated Si Substrate

C. B. Li, K. Usami, H. Mizuta, and S. Oda

AIP Conf. Proc. 1199, pp. 11-12; doi:http://dx.doi.org/10.1063/1.3295325 (2 pages)

Online Publication Date: 15 January 2010

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The synthesis of Ge nanowires on H‐terminated Si substrate is discussed in detail. The surface condition, growth temperature and substrate orientation have the important influences on the growth of Ge nanowires. Without HF treatment, it is difficult to grow high density Ge nanowires. After removal of SiO2 overlayer caused by silicon migration and nature oxidization, high‐density Ge nanowires can be grown.
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73.63.Bd Nanocrystalline materials
61.80.Fe Electron and positron radiation effects
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
82.60.Nh Thermodynamics of nucleation
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A tight‐binding investigation of temperature effects on the mono‐hydride diamond surface

R. Ramos and M. J. Caldas

AIP Conf. Proc. 1199, pp. 13-14; doi:http://dx.doi.org/10.1063/1.3295335 (2 pages)

Online Publication Date: 15 January 2010

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We present a study of surface evolution of hydrogenated diamond surfaces at finite temperature, focusing on the thermal behavior of monohydrogenated structures, comparing the ideal and stepped sufaces. Performing anneal cycles at different temperatures, from 0 K up to 1000 K, we found, for the stepped structure, hydrogen migration to the subsurface region, which is not observed for the ideal structure even at 1500 K. This indicates a correspondence between roughness of the surface and hydrogen subsurface insertion.
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81.05.uj Diamond/nanocarbon composites
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
83.10.Mj Molecular dynamics, Brownian dynamics
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Influence Of Sb Induced Surface Faceting On Structural Properties Of Relaxed Ge Films On Si(001)

T. F. Wietler, E. P. Rugeramigabo, E. Bugiel, and K. R. Hofmann

AIP Conf. Proc. 1199, pp. 15-16; doi:http://dx.doi.org/10.1063/1.3295345 (2 pages)

Online Publication Date: 15 January 2010

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In this paper, we investigated the influence of changes in the initial micro‐faceting induced by different Sb coverages on the structural properties of relaxed Ge films on Si(001). Two cases of surfactant‐induced micro‐faceted surfaces, exhibiting <110>‐ and <100>‐oriented troughs for high and low Sb‐coverage, respectively, were carefully prepared and 1 μm thick Ge layers were grown. Transmission electron microscopy and x‐ray diffraction were used to explore the effects that differently oriented surfactant‐induced micro‐facets exert on the structural film properties, in particular with regard to the Ge∕Si interface.
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68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
61.72.uf Ge and Si
68.37.Lp Transmission electron microscopy (TEM)
61.05.cp X-ray diffraction
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Photocurrent Enhancement Induced By Interface Modifications Due To Low Dose Electron Irradiation Of Amorphous∕Crystalline Silicon Heterojunctions

Heinz‐Christoph Neitzert, Manuela Ferrara, Wolfgang Fahrner, Maximilian Scherff, Arjen Klaver, and Rene van Swaaij

AIP Conf. Proc. 1199, pp. 17-18; doi:http://dx.doi.org/10.1063/1.3295356 (2 pages)

Online Publication Date: 15 January 2010

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A series of n‐type amorphous silicon∕p‐type crystalline silicon solar cells has been exposed to different fluences of 1 MeV electrons. For intermediate fluences up to 1.1013 electrons/cm2, an enhancement of the spectral response at shorter wavelengths and a increase of the short circuit current has been observed, while for higher fluences the usual device degradation due to the decrease of the charge carrier diffusion length in the crystalline silicon base after irradiation has been found.
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84.60.Jt Photoelectric conversion
61.72.uf Ge and Si
61.80.Fe Electron and positron radiation effects
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Influence of Cross‐Correlation of Rough Boundaries on Reflectance of Thin Films on GaAs and Si Substrates

František Vižd’a, Ivan Ohlídal, and Vojtěch Hrubý

AIP Conf. Proc. 1199, pp. 19-20; doi:http://dx.doi.org/10.1063/1.3295367 (2 pages)

Online Publication Date: 15 January 2010

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In this contribution the reflectance of thin films on semiconductor substrates with correlated randomly rough boundaries is analyzed. The theoretical approach is based on the scalar theory of diffraction of light. The numerical analysis of the reflectance is performed for rough thin films on GaAs and Si substrates. This analysis demonstrates that the reflectance depends not only on the rms values of the heights of the irregularities of the boundary roughness but it also depends on values of cross‐correlation coefficients between the rough boundaries. The magnitudes of boundary roughness and cross‐correlation between the rough boundaries depend on the technological procedures of creating thin film systems. By interpreting the measured reflectance spectra, the values of optical and roughness parameters can be determined.
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78.67.Pt Multilayers; superlattices; photonic structures; metamaterials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
61.72.uf Ge and Si
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In adsorption and diffusion on In‐rich (2×4) reconstructed InGaAs surfaces on GaAs(001)

Marcello Rosini, Maria Clelia Righi, Peter Kratzer, and Rita Magri

AIP Conf. Proc. 1199, pp. 21-22; doi:http://dx.doi.org/10.1063/1.3295378 (2 pages)

Online Publication Date: 15 January 2010

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We investigate the potential energy surface (PES) and the adsorption properties of an In adatom on InAs (2×4) reconstructed wetting layers (WLs) deposited on a GaAs substrate. The results are then used to derive the diffusion properties of a single In adatom on the WLs. We find that: (i) the adsorbate diffusion is highly anisotropic; (ii) the adsorption sites within the As dimers have to be taken into account since they strongly affect diffusion; (iii) the most stable adsorption sites are the ones within the dimers and those located besides the in‐dimers.
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82.20.Kh Potential energy surfaces for chemical reactions
82.60.Nh Thermodynamics of nucleation
31.15.B- Approximate calculations
82.20.Db Transition state theory and statistical theories of rate constants
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Initial Growth Of Thin Hydrogenated Amorphous Silicon Layer On Low Conductivity Substrates Monitored By In‐situ Transient Microwave Photoconductivity Measurements

Heinz‐Christoph Neitzert and Marinus Kunst

AIP Conf. Proc. 1199, pp. 23-24; doi:http://dx.doi.org/10.1063/1.3295388 (2 pages)

Online Publication Date: 15 January 2010

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The monitoring of the microwave reflection changes after pulsed laser illumination enables the in‐situ characterization of important optical and electrical material parameters during the growth of intrinsic hydrogenated amorphous silicon on low conductivity substrates.
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73.50.Pz Photoconduction and photovoltaic effects
78.70.Gq Microwave and radio-frequency interactions
75.50.Kj Amorphous and quasicrystalline magnetic materials
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GaN Surface Quantum Well In AlGaN∕GaN Transistor Heterostructure Studied By Contactless Electroreflectance

R. Kudrawiec, M. Gladysiewicz, J. Misiewicz, R. Paszkiewicz, B. Pszkiewicz, and M. Tłaczała

AIP Conf. Proc. 1199, pp. 25-26; doi:http://dx.doi.org/10.1063/1.3295398 (2 pages) | Cited 1 time

Online Publication Date: 15 January 2010

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Contactless electroreflectance (CER) has been applied to study optical transitions in GaN capped AlGaN∕GaN transistor heterostructure. In addition to strong AlGaN‐related resonance, a clear CER resonance has been observed at the energy of 3.68 eV. This resonance has been attributed to the optical transition within the GaN cap layer which creates a surface quantum well (QW). The confinement energy and the electron‐hole overlap integral for the surface QW have been calculated within the electron effective mass approximation. A good agreement between experimental data and theoretical calculations have been found.
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78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.67.De Quantum wells
78.40.Fy Semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
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Alkali Metal Induced Two Dimensional Electron Systems at Cleaved Surfaces of InAs

R. Masutomi, M. Minowa, T. Mochizuki, and T. Okamoto

AIP Conf. Proc. 1199, pp. 27-28; doi:http://dx.doi.org/10.1063/1.3295409 (2 pages)

Online Publication Date: 15 January 2010

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The authors have performed low‐temperature in‐plane magnetotransport measurements on two‐dimensional electron systems induced by deposition of Cs or Na at in situ cleaved surfaces of p‐type InAs. The coverage dependence of the surface electron density Ns strongly supports a simple model based on a surface donor level lying above the conduction band minimum. The maximum Fermi level positions obtained from the saturation values of Ns are compared to those of previous photoelectron spectroscopy measurements.
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71.20.Dg Alkali and alkaline earth metals
71.20.-b Electron density of states and band structure of crystalline solids
82.80.Pv Electron spectroscopy (X-ray photoelectron (XPS), Auger electron spectroscopy (AES), etc.)
81.70.Jb Chemical composition analysis, chemical depth and dopant profiling
82.45.Mp Thin layers, films, monolayers, membranes
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Study of PbTe p‐Type Doping With BaF2

U. A. Mengui, P. H. O. Rappl, B. Díaz, H. Closs, A. Y. Ueta, and E. Abramof

AIP Conf. Proc. 1199, pp. 29-30; doi:http://dx.doi.org/10.1063/1.3295420 (2 pages)

Online Publication Date: 15 January 2010

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We investigate here the electrical and structural properties of PbTe layers doped with BaF2. The layers were grown on (111) BaF2 substrates by molecular beam epitaxy. The nominal doping level, defined as the beam flux ratio between BaF2 and PbTe, was varied from 0.02 to 1%. The hole concentration increases monotonously from 5×1017 to 1×1019 cm−3 as the doping level is raised from 0.02 to 0.4%, and saturates at p ∼ 1019 cm−3 for higher doping levels. This result demonstrates that PbTe can be effectively p‐type doped with BaF2. Even for the highest doping levels, the PbTe layers remained with a good structural quality, as evidenced by the (222) x‐ray rocking curves.
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81.70.Jb Chemical composition analysis, chemical depth and dopant profiling
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
61.66.Bi Elemental solids
61.66.Dk Alloys
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High Resolution Photoluminescence of Copper, Silver, Gold and Lithium‐related Isoelectronic Bound Excitons in Highly Enriched 28Si

M. Steger, A. Yang, M. L. W. Thewalt, H. Riemann, N. V. Abrosimov, P. Becker, and H.‐J. Pohl

AIP Conf. Proc. 1199, pp. 33-34; doi:http://dx.doi.org/10.1063/1.3295441 (2 pages) | Cited 1 time

Online Publication Date: 15 January 2010

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Isotopic fingerprints of Li, Cu, Ag and Au in IBE centers are observed. A family of 4‐centers is suggested.
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78.55.Ap Elemental semiconductors
71.35.Ee Electron-hole drops and electron-hole plasma
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
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Many‐body Effects in Conductivity of Disordered Semiconductors

Michael Pollak, Andres M. Somoza, and Miguel Ortuño

AIP Conf. Proc. 1199, pp. 35-36; doi:http://dx.doi.org/10.1063/1.3295451 (2 pages)

Online Publication Date: 15 January 2010

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The work deals with a long standing problem of the importance of many‐body effects in electron glasses. The paper has two parts, a computer simulation and an analytical many‐body theory. Both include many‐body effects.
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73.20.-r Electron states at surfaces and interfaces
72.10.Di Scattering by phonons, magnons, and other nonlocalized excitations
72.80.Ng Disordered solids
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Large Magnetoresistive Effect Enhanced by Space‐Charge Effect in Silicon

Michael P. Delmo, Shinpei Yamamoto, Shinya Kasai, Teruo Ono, and Kensuke Kobayashi

AIP Conf. Proc. 1199, pp. 37-38; doi:http://dx.doi.org/10.1063/1.3295461 (2 pages)

Online Publication Date: 15 January 2010

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We report observation of a very large magnetoresistance (MR) effect in the space‐charge regime in lightly doped silicon with the Schottky contacts. It is found that the device resistance increases more than 30,000% when the magnetic field is changed from 0 to 1 T at 25 K. We propose that charge correlation in magnetic field in the space‐charge regime in the Schottky barrier enhances the MR effect.
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72.15.Gd Galvanomagnetic and other magnetotransport effects
73.30.+y Surface double layers, Schottky barriers, and work functions
85.40.Hp Lithography, masks and pattern transfer
73.40.Cg Contact resistance, contact potential
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Direct absorption edge in GeSiSn alloys

V. R. D’Costa, Y.‐Y. Fang, J. Tolle, J. Kouvetakis, and J. Menéndez

AIP Conf. Proc. 1199, pp. 39-40; doi:http://dx.doi.org/10.1063/1.3295471 (2 pages)

Online Publication Date: 15 January 2010

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The lowest direct absorption edge E0 in ternary Ge1‐x‐ySixSny alloys was measured in films grown lattice‐matched to Ge using spectroscopic ellipsometry and photoreflectance. The sample choice is dictated by possible applications of Ge1‐x‐ySixSny in photovoltaics as the long‐sought ∼1 eV gap material to complement Ge∕InGaAs∕InGaP multijunctions. The compositional dependence of the E0 transition is analyzed in detail.
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73.61.Cw Elemental semiconductors
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
84.60.Jt Photoelectric conversion
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
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Lattice and Hydrogen Dynamics in Hydrogenated Amorphous Silicon: First‐Principles Molecular Dynamics versus Experiment

A. I. Shkrebtii, I. M. Kupchak, and F. Gaspari

AIP Conf. Proc. 1199, pp. 41-42; doi:http://dx.doi.org/10.1063/1.3295483 (2 pages)

Online Publication Date: 15 January 2010

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We present the results of extensive ab‐initio Molecular Dynamics (AIMD) simulation of the structural, electronic and vibrational properties of hydrogenated amorphous silicon (a‐Si:H) in a wide range of hydrogen concentration and preparation conditions. We focus mainly on vibrational spectra as important and unique signatures of a variety of a‐Si:H properties. A comparison with experiment allowed us to correlate processes at microscopic atomic level, such as vibrations, chemical bonding and diffusion with macroscopic properties of the amorphous material.
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83.10.Mj Molecular dynamics, Brownian dynamics
61.72.uf Ge and Si
61.72.Cc Kinetics of defect formation and annealing
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
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Optical Phonons In InAlAs Thin Layers: Raman And IR Study

A. Milekhin, A. Kalagin, A. Vasilenko, A. Toropov, N. Surovtsev, and D. R. T. Zahn

AIP Conf. Proc. 1199, pp. 43-44; doi:http://dx.doi.org/10.1063/1.3295494 (2 pages)

Online Publication Date: 15 January 2010

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We present a study of the optical phonon spectrum of relaxed InxAl1−xAs epitaxial layers grown by molecular‐beam epitaxy on GaAs substrates in the whole range of In content (x  =  0÷1) using macro‐ and micro‐Raman and IR spectroscopies.
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73.61.Ey III-V semiconductors
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
71.38.-k Polarons and electron-phonon interactions
61.72.Dd Experimental determination of defects by diffraction and scattering
82.80.Gk Analytical methods involving vibrational spectroscopy
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Microwave Magnetotransport Investigations of Photogenerated Carriers in Dilute Nitride Semiconductors

Horia‐Eugen Porteanu, Oleg Loginenko, and Frederick Koch

AIP Conf. Proc. 1199, pp. 45-46; doi:http://dx.doi.org/10.1063/1.3295505 (2 pages)

Online Publication Date: 15 January 2010

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It is shown that photogenerated electronic transport in heterostructures containing dilute nitride semiconductors takes place mainly in the interfacing material, having higher mobility and higher energy gap, in spite of the expected quick relaxation of electrons and holes. It is the consequence of the very bad mobility of the dilute nitride material. We estimate the mobility to be less than 2 cm2/Vs for 3% nitrogen content. This value of the mobility is an indication of extremely strong localization of carriers, in contrast to the extended states suggested by a band description.
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73.40.Sx Metal-semiconductor-metal structures
73.63.Bd Nanocrystalline materials
76.40.+b Diamagnetic and cyclotron resonances
78.55.Et II-VI semiconductors
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Dilute Nitride Alloys—the Optical Evidence for Carrier Localization

Horia‐Eugen Porteanu, Oleg Loginenko, and Frederick Koch

AIP Conf. Proc. 1199, pp. 47-48; doi:http://dx.doi.org/10.1063/1.3295515 (2 pages)

Online Publication Date: 15 January 2010

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The photoluminescence of dilute nitride semiconductors shows a number of features that are not common for other semiconductors, even for compound semiconductors. We studied several MBE grown InGaAsN samples with a nitrogen content between 0.9 and 1.8% and a MOCVD grown sample with 3% N and evidenced the strong localization of carriers. The results are presented in contrast to the photoluminescence behavior of InGaAs.
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78.55.Cr III-V semiconductors
78.40.Fy Semiconductors
71.20.-b Electron density of states and band structure of crystalline solids
73.21.Fg Quantum wells
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Low‐temperature microwave magnetoresistance in p‐Ge and the problem of averaging of the effective masses of light and heavy holes

A. I. Veinger, A. G. Zabrodskii, T. V. Tisnek, and S. I. Goloshchapov

AIP Conf. Proc. 1199, pp. 49-50; doi:http://dx.doi.org/10.1063/1.3295526 (2 pages)

Online Publication Date: 15 January 2010

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A problem of the final time of the effective mass averaging in the system of light and heavy holes is manifested in a study of magnetoresistance (MR) in p‐Ge at low temperatures and a frequency of 10 GHz. It is shown that the effective mass averaging takes place in the time which is more than 10−10 sec and is significantly more than the time of momentum relaxation. The experimentally estimated averaging time turned out to be connected with the time of the energy relaxation.
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73.43.Qt Magnetoresistance
71.20.Mq Elemental semiconductors
72.15.Lh Relaxation times and mean free paths
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Hole Transport in HgCdTe

O. V. S. N. Murthy, V. Venkataraman, and R. K. Sharma

AIP Conf. Proc. 1199, pp. 51-52; doi:http://dx.doi.org/10.1063/1.3295537 (2 pages)

Online Publication Date: 15 January 2010

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While Mercury Cadmium Telluride (MCT) epilayers are important from a technological point of view, bulk crystals are ideally suited for studies of fundamental material properties such as mobility. Even though electronic transport has been treated well in the literature hole transport has not been studied much in MCT despite the popular device structure being n+ on p. This may be due to the high electron mobility dominating low magnetic field transport even in p‐type samples. In comparison of theoretical models with experimental data analyzed using multicarrier methods, relaxation time approximation has been used in some places which is not rigorously justified for polar optical phonon scattering. We use high pulsed magnetic fields to probe the low mobility holes in bulk p‐type Hg0.79Cd0.21Te bulk crystals. Multicarrier analysis was used to extract hole mobilities from measured conductivity tensor at higher temperatures from 200 K–300 K in magnetic fields upto 15T. We have solved Boltzmann transport equation numerically without relaxation time approximation to include polar optical phonon scattering. Other scattering mechanisms taken into account are: ionized impurity, nonpolar optical, acoustic. Results are presented comparing our data with the calculated mobility.
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81.70.Jb Chemical composition analysis, chemical depth and dopant profiling
73.63.Bd Nanocrystalline materials
72.20.Ee Mobility edges; hopping transport
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Temperature Dependence Of Current‐Voltage Characteristics Of Pt∕InN Schottky Barrier Diodes

Victor‐Tapio Rangel‐Kuoppa, Sami Suihkonen, Markku Sopanen, and Harri Lipsanen

AIP Conf. Proc. 1199, pp. 53-54; doi:http://dx.doi.org/10.1063/1.3295546 (2 pages)

Online Publication Date: 15 January 2010

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The Current‐Voltage (IV) measurements on Pt∕InN Schottky barrier diodes in the temperature range 10–280 K were done. It was found that the contact was Schottky up to 280 K, becoming irreversible ohmic for higher temperatures. The ideality factor, the saturation current and the apparent barrier height were calculated by using the thermionic emission (TE) theory. The ideality factor is temperature dependent, while the saturation current and the barrier height are not. The non conventional Richardson plot exhibits good linearity, corresponding to an activation energy of 2.08 eV and a Richardson constant of 18.7 A m−2 K−2. The Cheung’s method to estimate the value of a possible series resistance RS yields a negligible resistance. From reverse‐bias IV analysis, it is found that the experimental carrier density (ND) value increases with temperature.
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73.30.+y Surface double layers, Schottky barriers, and work functions
79.60.-i Photoemission and photoelectron spectra
32.50.+d Fluorescence, phosphorescence (including quenching)
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