Properties Of InSb Thin Films Research Articles

Growth and Characterization of InSb Thin Films on GaAs (001) without Any Buffer Layers by MBE**Supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No 2015094, the National Natural Science Foundation of China under Grant Nos 61204012, 61274049 and 61376058, the Beijing Natural Science Foundation under Grant Nos 4142053 and 4132070, and the Beijing Nova

We report the growth of InSb layers directly on GaAs (001) substrates without any buffer layers by molecular beam epitaxy (MBE). Influences of growth temperature and V/III flux ratios on the crystal quality, the surface morphology and the electrical properties of InSb thin films are investigated. The InSb samples with room-temperature mobility of 44600 cm/Vs are grown under optimized growth conditions. The effect of defects in InSb epitaxial on the electrical properties is researched, and we infer that the formation of In vacancy (V) and Sb anti-site (Sb defects is the main reason for concentrations changing with growth temperature and Sb/In flux ratios. The mobility of the InSb sample as a function of temperature ranging from 90 K to 360 K is demonstrated and the dislocation scattering mechanism and phonon scattering mechanism are discussed.

The Effect of a Buffer Layer on the Electric Properties of InSb Thin Films Grown by Metalorganic Vapor Phase Epitaxy

We have studied the thermoelectric properties of InSb thin films. They were prepared by metalorganic vapor phase epitaxy on sapphire substrate using sputtered InAs buffer layer. Substrate temperature during the deposition of InAs buffer layer was changed between 65°C and 250°C. Electrical properties, thermoelectric properties, and crystalline properties of InSb thin films with a InAs buffer were assessed using Hall measurement, Power factor and X-ray diffraction. The power factor of InSb was as high as 2.1×10−4 W/mK2 at a deposition temperature of 150°C of InAs.

Electrical properties of InSb thin films with an InAsSb buffer layer grown by MOVPE

AbstractWe have studied the electrical and thermoelectric properties of InSb thin films. The films were prepared by metalorganic vapor phase epitaxy on a sapphire substrate using an InAsSb buffer layer with a thickness of 0.9 nm, 2.6 nm, 5.1 nm, 10 nm, or 15 nm. The electrical and thermoelectric properties and the crystallinity of InSb thin films with an InAsSb buffer layer were evaluated. Maximum values of electron mobility and power factor were 10,240 cm2/Vs and 3.73 × 10‐4W/mK2, respectively, at room temperature for InSb with an InAsSb buffer layer of 5.1 nm thickness. On the basis of temperature dependence of electrical properties and a simulation, we proposed and showed that two‐conduction layers exist between InSb and substrate probably caused by their lattice‐mismatch. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Stress reduction and electric properties of InSb thin films grown by metalorganic vapor phase epitaxy on sapphire substrates with an InAs buffer layer

InSb thin films were grown by metalorganic vapor phase epitaxy using an InAs buffer layer on sapphire (0001) substrates. The stresses and strains in InSb were controlled by the thickness of the InAs buffer layer, and it was found that with decreasing compressive stress in InSb, the crystalline quality and the electrical properties improved. The thermoelectric properties of InSb were assessed and it was found that the power factor of InSb with a thickness of 5 μm reached as high as 5.8 × 10 −3 W/mK 2 at 600 K.

The Effect of InAsSb Buffer Layer on the Thermoelectric Properties of MOCVD-Grown InSb Thin Films

We have studied the thermoelectric properties of InSb thin films. They were prepared by metalorganic chemical vapor deposition on sapphire substrate using InAsSb buffer layer. the thickness of InAsSb buffer layer was changed as 0.9nm, 2.6nm, 5.1nm, 10nm, and 15nm. Electrical properties, thermoelectric properties, and crystalline properties of InSb thin films with a InAsSb buffer were assessed using Hall measurement, Power factor and X-ray diffraction. Using InAsSb buffer of 5.1nm, the mobility of InSb was as high as 10240cm2/Vs and the Power factor of InSb was as high as 3.73×10-4W/mK2.

Exploration of the inherent magnetoresistance in InSb thin films

The depth-dependent electrical properties of InSb thin films grown on GaAs substrates result in an inherent magnetoresistance in the layers. For certain applications it is important to be able to manipulate this effect controllably. This paper demonstrates both experimentally and theoretically that the magnitude of the magnetoresistance can be dramatically changed by epilayer design. We show that the inclusion of a doped region in part of the layer structure allows the inherent magnetoresistance to be changed by a factor of 40.

Thermoelectric and Electrical Properties of InSb Thin Films Prepared by Metalorganic Chemical Vapor Deposition

AbstractWe studied the thermoelectric and electrical properties of InSb thin films prepared by metalorganic chemical vapor deposition. The thermoelectric properties were evaluated using power factor (Pf =α2/Ï), which is an important criterion, and a value of 10-3 W/mK2 is a standard for practical use. Maximum value of Pf was 2.4×10-3W/mK2 at 600K for 1-μm-thick InSb, 3.4×10-3W/mK2 at 600K for 3-μm-thick InSb, and 5.8×10-3W/mK2 at 600K for 5-μm-thick InSb. On the other hand, the maximum Pf of bulk-InSb was 5.4×10-3W/mK2 at 600K.

Optical and transport properties of InSb thin films grown on GaAs by metalorganic chemical vapor deposition

Optical and transport properties of InSb thin films grown on GaAs by metalorganic chemical vapor deposition (MOCVD) have been investigated by far-infrared (FIR) reflectance spectroscopy. The lattice vibration behaviors of a series of MOCVD InSb/GaAs(100) materials grown under different growth conditions were studied. Effects of III–V source ratios on the films crystalline quality were examined. Two additional weak modes in the wavenumber regions of 210–240 cm − 1 were observed and they appeared more prominent at low temperatures. Interference fringe effects modify the FIR reflectance band of the GaAs substrate, which are related to the uniformity of film thickness and crystalline perfection. The dielectric constant, phonon modes and other optical parameters, as well as transport properties including carrier concentration, mobility, effective mass were calculated theoretically and compared with experimental results. The obtained distribution values of the InSb LO phonon mode frequency, line width, relative integrated intensity ratio between the forbidden and defect-related TO phonon and the allowed LO mode are adopted as figures of merit for the quality of the InSb films. The electrical transport properties of carrier concentration, mobility, and effective mass as well as the dielectric constant of these films have been determined by optical method non-destructively.

Textural properties of InSb thin films

The growth of flash-evaporated InSb films on non-oriented substrates between 160°C and 450°C is investigated. For the substrate temperatures T s<400°C the films are textured in the (1 1 0) plane, and their average grain size is of the order of 0.2 μm. At T s⩾400°C the preferred grains orientation becomes a mixture of the (1 1 0) and the (1 1 1), with a predominance of the (1 1 1) orientation at the highest temperatures. The average grain size increases to about 1 μm. The low-temperature texture in the (1 1 0) plane can be explained by the kinetic theory of the nucleation process and grain development, whereas the high-temperature orientation distribution can be explained by the thermodynamic requirements of minimization of the surface energy of the system. The latter consideration assumes that the lowest surface energy planes in InSb are (1 1 0), (1 1 1) A and (1 1 1) B and that the energies have comparable magnitudes.

Effect of Heat Treatment on the Microstructures and Electrical Properties of Insb Thin Films

ABSTRACTPolycrystalline InSb thin films have been prepared by two-source thermal evaporation method. The as-deposited randomly oriented thin films develop (111) preferred orientation upon heat treatment of different maximum setting temperatures, T(max)s. Under different T(max)s, the elongate (111) grains rotate gradually the direction of the elongation respect to the thermally oxidized Si(100) substrate.The (111) preferred orientation has been seen from both cross-sectional TEM and X-ray diffraction patterns. The electrical mobility value of the thin film has been measured by the Van der Pauw′s method. A dramatic increase in the electrical mobility from few thousands, for the as-deposited film, to intermediate values of 15,000-30,000 cm2/v-s and the highest value of 36,000 cm2/v-s for thin films subjected to different T(max)s, can be correlated well to the corresponding microstruetures.

Dendritic crystal regrowth and electrical properties of InSb thin films prepared by vacuum evaporation

InSb thin films were evaporated and deposited on mica substrates by a simple vacuum evaporation method. A recrystallization of the deposit was observed at the last stage of the thin-film deposition. The recrystallization showed a dendritic crystal regrowth and the recrystallized area obtained one order of magnitude higher electron mobility than that of the as-deposited area. The maximum electron mobility obtained at room temperature was 6.0×104 cm2 /V s with impurity concentration of 5.8×1015 cm−3 . The crystal regrowth was found to be due to the melting-solidification process through the vapor-liquid-solid mechanism.

Preparation and electrical properties of InSb thin films heavily doped with tellurium, selenium and sulphur

A method of controlled donor doping of flash-evaporated InSb thin films in the concentration range 10 17−10 19 cm −3 is described. When such films are regrown from the melt the electron concentration increases several times and the room temperature electron mobility increases by about an order of magnitude. The room temperature mobility of the regrown films is close to that observed in bulk InSb. The temperature dependence of the mobility between 80 and 700 K shows that barrier scattering plays an important role in all flash-evaporated and melt-regrown films with effective donor concentrations N d of 10 18 cm −3 or less. In the flash- evaporated films the barrier height increases from a value of 65 meV for N d = 10 17 cm -3 to 150 meV for N d = 9×10 18 cm −3. No such increase is observed in regrown films. This suggests that the barriers in the two types of films are different. The increase in electron concentration in regrown films is discussed and the most consistent explanation of the effect is that a large number of conduction electrons are trapped at grain boundaries in the flash-evaporated films. The application of the heavily doped melt-regrown InSb films as Hall generators is also discussed.

The hall mobility of charge carriers at room temperature in InSb thin films regrown from the melt

The experimental and theoretical dependence of the magnetoresistivity on magnetic field strength at room temperature in intrinsic and electrically homogeneous melt-grown InSb thin films was investigated. The electron mobility and the heavy and light hole mobilities were determined by fitting the calculated curves to the experimental points. On taking into account the similarities in the electrical and galvanomagnetic properties of InSb thin films and of uniaxially compressed InSb crystals it was concluded that the main scattering centres in the InSb films are ionized vacancies and interstitials in approximately equal numbers. The density of these point defects increases in films thinner than 3 μm.

Electrical properties of InSb thin films in low noise hall generators on a ferrite substrate

Electrical properties of InSb thin films in low noise hall generators on a ferrite substrate

Structure and electrical properties of InSb thin films prepared by plasmatic sputtering

This paper describes the apparatus for the plasmatic sputtering and preparation of InSb thin films. The structure and the dependence of the resistance of InSb films on the sputtering time at different temperatures are introduced. The dependences of the Hall constant, Hall mobility and electric conductivity of polycrystalline thin films on the film thickness is explained.