Search

In this paper, different PV cell materials, such as silicon, germanium, cadmium telluride, indium phosphide, and gallium arsenide, are considered to analysis. Here, estimation of built-in voltage, output current, and cost estimation for the PV system with generation capacity of 1 kW for each material is considered. The levelized cost of electricity (LCOE) was estimated for all types of PV cell materials. The performance curve for PV cells was constructed with respect to the output current, temperature, PV cell area, built-in voltage, LCOE, solar-PV cell operational life span and energy generation of entire period.

Heavy-metal-free indium phosphide (InP)-based quantum dots (QDs) have attracted much attention as materials for display applications. Methods such as introducing Zn in the core of InP QDs and passivating wide band-gap materials have been used to improve the luminescent properties of InP QDs. Herein, we investigated the photophysical properties of the In(Zn)P core QDs with the influence of the Zn additive on the InP QDs. The near band edge photoluminescence (PL) of the In(Zn)P QDs was spectrally asymmetric in shape, with a redshifted side peak originating from a Zn impurity that induced shallow defect sites, resulting in PL linewidth broadening. The shallow trap emission of the In(Zn)P QDs disappeared after the overcoating of the ZnSeS passivated the shell layers, and the PL linewidth of In(Zn)P/ZnSeS (core/shell) QDs was solely determined by the band-edge excitonic energy distribution caused by the size dispersion in ensemble QD systems. We expect that the understanding the photophysical properties of In(Zn)P-based QDs future strategies to narrow the ensemble emission line of the InP-based QD synthesis.

In this paper, the spin-transport properties of Gallium Nitride/Indium Phosphide/Gallium Nitride (GaN/InP/GaN) all semiconductor magnetic tunnel junction (MTJ) has been investigated. To induce ferromagnetic properties in the electrodes made of GaN, the electrodes are doped with Manganese (Mn). The central region is made of InP, which is a large bandgap material, thereby improving the zero-bias magnetoresistance. The electrodes used in the proposed device show ferromagnetic behavior beyond room temperature without the conductivity mismatch problem. Finally, a comparison based on the proposed device's performance parameters with the devices reported in the open literature is carried out in this work. The comparison clearly shows the pre-eminence of the proposed device over the previously reported devices as it has high TMR (1.97 × 104%) and works over a wide range of temperature.

In-situ angle-dispersive X-ray diffraction (ADXRD) and Raman scattering were carried out to delineate the phase transitions under pressure in p-type zinc-doped indium phosphide (InP:Zn) at ambient temperature. The ADXRD measurements with pressure up to 17.3(2) GPa reveal that InP:Zn transforms from zinc-blende (ZB) to rock-salt (RS) structure in a pressure range of 8.1(2) - 8.6(1) GPa. The Raman scattering measurements indicate that the phase transition proceeds continuously over a wide range of pressure and reaches completion at the highest pressure applied (14.5(2) GPa) with significant metallization, as suggested by the disappearance of the transverse optical (TO) and longitudinal optical (LO) modes. In contrast, originally absent at ambient pressure, additional Raman shift of Zn local vibrational modes (LVMs), appeared at 276 cm-1 and 420.7(1) cm-1 within the pressure range of 2.2(1) up to 10.1(2) GPa, which can be attributed to Zn3P2 and VPZnInVP LO modes, respectively. The zero-pressure isothermal bulk moduli and its first order pressure derivatives for the zinc-blende InP:Zn are 79.44(2) GPa and 3.92(1), respectively. A total enthalpy change of about 45.45 KJ•mole-1 was derived for the ZB to RS structure transformation occurring at the pressure of 8.6(1) GPa. The present results suggest that diffusion of Zn in InP:Zn may have been governed by the modified substitution and interstitial (S–I) mechanism. Moreover, comparisons on the pressure-dependent behaviors in InP:Zn, InP:S, and InP:Fe extrinsically doped systems revealed that the exact type of the defects introduced into the lattice upon doping may have played crucial roles in the pressure-induced phase transitions.

Indium phosphide (InP) surfaces develop a pronounced nanostructured texture upon irradiation by energetic ion beams. We have observed the mechanism of nanostructure evolution of InP under irradiation by an Ar gas cluster ion beam (GCIB) using helium ion microscopy (HIM). Initially, metallic indium nanoparticles form on the surface after removal of the top-most oxide layer. These nanoparticles form a mask which shadows the underlying InP. As the ion dose is increased, the masking effect results in substantial nanostructured topography in the form of pillars or nanocones, oriented along the axis of the incident GCIB. The surface sensitivity and high resolution of the HIM facilitates the direct observation of the metallic indium cap at the top of the pillars.

In this work, we have investigated the growth of highly n-doped gallium arsenide (GaAs) and gallium indium phosphide (GaInP) with tellurium (Te) by metal organic vapor phase epitaxy (MOVPE) using diisopropyl telluride (DIPTe), aiming at fabricating high performances tunnel junctions. A parametric study is performed in order to optimize the n++-type doping. Concentrations above 2.7 × 1019 cm−3 were achieved in both GaAs and GaInP layers. Using these Te-doped layers, we fabricated both n on p (n/p) and p on n (p/n) tunnel junctions. The p/n tunnel junction required additional annealing steps during growth, due to memory effect and surfactant properties of Te. We characterized GaAs/GaAs, GaAs/AlGaAs and AlGaAs/GaInP tunnel junctions with peak tunneling current densities as high as 250, 3000 and 1500 A/cm2 respectively. These tunnel junction performances are suitable for multijunction solar cells operating under high concentration.

The narrow, color-tunable luminescence of quantum dots (QDs) brought them to the forefront of commercial lighting and solar cells. Indium phosphide (InP) QDs emerged as the most promising replacement for cadmium selenide-based QDs for luminescence in the visible range (450–700 nm). Here, we consider areas of QD synthesis most relevant for future advances in InP. Advances in precursor chemistry, namely single-source precursors, facilitate synthesis of materials with more homogeneous properties. These isolable intermediates have atomically precise structure that introduces a scheme for the atom economy in InP QD synthesis. Methods for obtaining luminescent InP QDs are presented with emphasis on shorter reaction times, fewer steps, and less hazardous reagents. With these advances in luminescence quantum yield (QY), minimization of sample heterogeneity, and enhanced stability, emphasis on reproducibility, safety, and other green chemistry principles can be prioritized. The methods reviewed here highlight areas conducive to goals related to material properties and greener synthetic methods.

In indium phosphide quantum dots (InP QDs), the presence of surface states due to unbonded indium or phosphorus atoms quenches its photoluminescence (PL) efficiencies. Hence, it is imperative to passivate these surface states to achieve high photoluminescence efficiencies of InP nanocrystals. In this work, a novel post-synthesis nascent H chemical treatment to enhance the quantum yield of single-pot, wet chemical route synthesized InP QD's is reported for the first time. The main advantages of this post-synthesis treatment are: (i) it is easy, inexpensive and reproducible and (ii) it does not involve harsh chemical treatment viz. dipping of InP QDs in HF-based solutions, nor it requires annealing at high temperatures which may be detrimental to the fragile structure of InP. The significant increment in PL intensity upon aforementioned hydrogen treatment is due to the passivation of surface states and structural recrystallization mechanism that promotes radiative recombination of electrons and holes and hence higher lifetime values. An enhancement in PL intensity of as-synthesized InP QDs upon nascent hydrogen treatment is quite remarkable and is even better than that accomplished by InP-ZnS core-shell QDs with similar size-distribution. The hydrophobicity of H-treated InP QD's is found to be more than untreated InP thus implying higher compactness and structural rigidity similar to as achieved by InP-ZnS core-shell QDs. Mechanisms related to nascent hydrogen treatment, photo-oxidation and PL enhancement and its effect on the surface stoichiometry of InP QDs are discussed via structural, morphological, compositional and optical studies corroborated by various complementary techniques viz. SEM, HRTEM, EDAX,NMR, DLS, Zeta Potential, Contact Angle, PL and Transient Absorption respectively. The application of InP films as a humidity sensor has been demonstrated and untreated InP film in particular shows higher sensitivity values upon exposure to humid treatment as compared with H-treated InP and InP-ZnS core-shell QD's respectively.

The electron and positron chemical potentials, positron affinity and bulk lifetime as well as the positronium work function in InP are investigated. The emphasis of this work is on the hydrostatic pressure effect on these features. The calculations are performed with a pseudopotential approach and the independent particle model. All parameters of interest are found to vary monotonically with pressure. Our findings showed that under compression the positron annihilates differently in InP semiconductor compound. At zero pressure, the positron bulk lifetime is calculated to be 243.47 ps. However, upon compression it decreases almost linearly suggesting the decrease of the crystal ionicity under applied pressure. The positronium work function is found to increase with raising pressure which indicates that under compression less positronium atoms will be formed in InP sample surface and ejected into the vacuum. The parameters investigated in the present work are important in slow-positron-beam experiments.

Here, we report the scalable preparation of Pt nanoparticles decorated indium phosphide nanopore arrays (Pt@InP NPAs) using a facile two-step etching method followed by a dipping and electrodeposition process. The morphology and element composition of the Pt@InP heterostructures were characterized. Photoelectrochemical properties of the Pt@InP electrodes were investigated under simulated sunlight irradiation. Compared to pristine InP NPAs, the resulting Pt@InP NPAs show a greatly increased photocurrent density and a largely improved onset potential for photoelectrochemical (PEC) hydrogen evolution. Electrochemical impedance spectroscopy reveals that the improved PEC performance is attributed to the enhanced charge transfer and the improved charge separation at Pt@InP NPAs/electrolyte interfaces.

In this work, we report the thermoelectric properties of indium phosphide (InP) in ground state Zinc-Blende (zb) structure and the pressure-driven Beryllium Oxide (β-BeO)-, wurtzite (wz)-, and Silicon Carbide (SiC)-phases using the first-principles approach. Their electrical and thermal conductivities, Seebeck coefficient (S), thermoelectric power factor (PF), and the figure-of-merit (zT) have been evaluated in detail. The S values of InP polytypes have been found typically larger than 230 μV/K when the Fermi-level is fixed inside the band gap edges, however, shifting the Fermi-level to the middle of the band gap has evolved S larger than 2000 μV/K. These polytypes of InP exhibited high electrical conductivities and significant S values that have induced substantial PFs. The maximal PFs have been recorded as 18.73 × 1010 W/mK2s for zb-InP, 14.04 × 1010 W/mK2s for wz-InP, 10.30 × 1010 W/mK2s for β-BeO-InP, and 11.14 × 1010 for SiC-InP. Our analysis shows that the recorded substantial PFs go through further improvement with an increase in temperature. The optimized electrons and holes dopings that resulted in the maximal PFs have been recognized as − 0.72, 1.75, 1.56, and 1.72 eV for zb-, wz-, β-BeO-, and SiC-type of InP. The zT values exhibited by these polytypes of InP approach to unity at moderate p-type doping level specifies their potential for applications in thermoelectric devices.

In this paper, three-dimensional (3D) graphene/P-type indium phosphide (P-InP) nanopillar Schottky junction near-infrared photodetectors based on TCAD were built. The simulation results show that the Schottky barrier height of near infrared photodetector increases with the decrease of nanopillar size when the height of nanopillar is 10 μm. At 0 V bias voltage, when the wavelength of incident light is 808 nm, the responsivity increases gradually with the decrease of the size of the nanopillar, and the electric field intensity in the depletion region increases obviously. When the size of the nanopillar is fixed and the height of the nanopillar approaches the width of the depletion region, the responsivity of the detector reaches the maximum value. It shows the nanopillar structure can significantly improve the performance of the photodetectors.

The optical properties of an epitaxial indium phosphide (InP) film deposited on an Fe compensated InP (InP:Fe) wafer have been measured at room temperature by ex-situ spectroscopic ellipsometry over a spectral range of 0.038–8.5 eV. The complex dielectric function spectra, e (E) = e1 (E) + ie2 (E), have been determined by fitting a parametric model to the experimental ellipsometric data. Kramers-Kronig consistent parameterizations have been applied to describe interband transitions and defect-based sub-bandgap absorption in the 0.73–8.5 eV spectral range, and both phonon modes and free carrier properties in the 0.038–0.73 eV range. Spectra in e from 0.73–8.5 eV shows ten higher energy interband critical point transitions at 1.36, 1.42, 3.14, 3.34, 4.71, 4.97, 5.88, 6.45, 7.88, and 8.22 eV. The direct band gap energy of 1.37 eV and Urbach energy 46 meV are also determined from spectra in e. A strong optical phonon mode is identified near 305 cm−1. Electronic transport properties, carrier concentration (N) and mobility (μ), calculated from Drude model with N = 1.9 × 1018 cm−3 and μ = 1559 cm2/Vs agree well with direct electrical Hall effect measurement values of N = 2.2 × 1018 cm−3 and μ = 1590 cm2/Vs. A parameterization of e from 0.038 to 8.5 eV for the epitaxial InP film is reported.

Large scale indium phosphide (InP) nanoneedles and nanotubes were synthesized through a facile solvothermal reaction. The morphology and microstructure of the samples were analyzed by employing scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and Ultraviolet-visible (UV–vis) spectroscopy. The room temperature photoluminescence (PL) measurements showed that the InP nanoneedles and nanotubes possessed a pronounced blue shift in contrast to the bulk counterpart, which was ascribed to the crystalline defects effect. Moreover, the InP nanotubes exhibited an enhanced photocatalytic performance as compared to the InP nanoneedles and nanoparticles.

This paper explores high efficiency of semiconductor grating structure at wavelength, 1550 nm for silicon on insulator (SOI) optical circuits. Here semiconductor grating structure is realized by the combination of silicon and compound semiconductor materials, where compound semiconductor gratings are envisaged by indium phosphide, Al80Ga20As and Al42Ga58As. Different types of losses in terms of absorption, reflection and diffraction including polarization are cogitated to investigate the efficiency of grating SOI structure at wavelength, 1550 nm. Interestingly, the absorption loss of above semiconductor grating is found to be zero at the above wavelength. Also the simulation was accomplished using plane wave expansion method, which leads to zero reflectance for the aforementioned structures at same wavelength. Simulation is also made for diffraction and polarization losses of above three semiconductor grating SOI structures. Simulation results reveal that diffraction efficiency is 1, (diffraction loss is zero) with respect to detune from Bragg’s angle which ranges from −12° to +12°. Additionally, the proposed structures encountered polarization losses. Present simulation results showed that polarization efficiency is more than 90% (polarization loss is less than 10%)in silicon −indium phosphide (Si-InP),silicon-Al80Ga20As (Si-Al80Ga20As) and silicon – Al42Ga58As (Si-Al42Ga58As) grating SOI structures with respect to same deviation. Since absorption, reflection and diffraction losses are zero, the overall transmitted efficiency depends on polarization efficiency and finally, with the combination of both absorption, reflection,diffraction and polarization loss,it is inferred that overall transmitted efficiency of semiconductor grating SOI structure is more than 90% with respect to same angle.

This work describes morphological and crystalline properties of the InAs islands grown on templates created by focused ion beam (FIB) on indium phosphide (InP) substrates. Regular arrangements of shallow holes are created on the InP (001) surfaces, acting as preferential nucleation sites for InAs islands grown by Metal-Organic Vapor Phase Epitaxy. Ion doses ranging from 1015 to 1016 Ga+/cm2 were used and islands were grown for two sub-monolayer coverages. We observe the formation of clusters in the inner surfaces of the FIB produced cavities and show that for low doses templates the nanostructures are mainly coherent while templates created with large ion doses lead to the growth of incoherent islands with larger island density. The modified island growth is described by a simple model based on the surface potential and the net adatom flow to the cavities. We observe that obtained morphologies result from a competition between coarsening and coalescence mechanisms.

The study investigated titanium dioxide (TiO2) on indium phosphide (InP) prepared by solution-gelation (sol-gel) process and application to InAlAs/InGaAs metal-oxide-semiconductor metamorphic high-electron-mobility transistor (MOS-MHEMT). The sol-gel TiO2 exhibits not only easy process and without plasma source, but also high dielectric constant to improve the interface state between metal and semiconductor. The InAlAs/InGaAs MHEMT with sol-gel processed TiO2 as gate oxide reveals superior electrical characteristics than the reference case. These electrical characteristics include better drain current density, larger turn-on voltage, improved reverse breakdown voltage, as well as smaller gate leakage current density. These results indicate the potentiality of the proposed sol-gel process TiO2 as gate oxide on InAlAs/InGaAs MHEMT for further power application.

Indium phosphide-based colloidal quantum dot (QD) light-emitting diodes represent a promising technology for various lighting applications. To promote this innovative technology closer to an industrialized production environment, the fabrication methods should be adapted. Hence it is necessary to replace the common spin-coating process under an inert atmosphere, by a more cost-efficient inkjet-printing process at ambient conditions. However, in our case, this transfer results in devices with limited performance and parasitic emission channels besides the desired QD emission. In this paper, we identify the physical origin of these parasitic emission channels for three different device layouts depending on the QD material as well as the number of inkjet-printed layers. For the first type of devices, a recombination process on the dopant of the electron transporting layer (ETL) as well as an exciplex formation at the interface between QDs and ETL was identified. For the next device layout, the introduction of a hole-conducting matrix embedding the QDs leads to a shift of the parasitic emission with contributions from the matrix material. Finally, the integration of a hole injection layer leads to a reduction of the undesired emission processes. For all three kinds of devices, the spacial separation of the dopant in the ETL from the QDs is a critical factor, since it directly influences the parasitic emission channels.

Indium phosphide nanowires (InPNWs) with an average diameter of 87 nm were successfully synthesised through thermal chemical vapour deposition (CVD) method. The smooth surface nanowires showed a relatively narrow size distribution of 70–105 nm. Temperature programmed desorption (TPD) was used to study the thermodynamic behaviour of gas desorption. The study revealed that gaseous CO and CH4 molecules bind to InPNW surface through chemical and physical adsorption, respectively. The Redhead method was used to estimate the enthalpy energy of desorption for CO and CH4 to be 142 kJ/mol and 38 kJ/mol. The sorption temperature ranges were found to be 220–260 C for CO and -50 to -20 C for CH4. InPNWs were used to fabricate a gas sensor electronic device and were tested for performance. The device showed a quick response time of 29.19 s for CO at 250 C, thus relatively faster than that of H2 and NO2.

The solar cell is a semiconductor device that converts sunlight into electricity. In this study, we used Analysis Microelectronic and Photonic Structures (AMPS-1D) simulator to show the performance analysis of Gallium Arsenide (GaAs) based solar cell model. A balance between semiconductor compositions, layer thickness and temperature dependence on the efficiency have been investigated as the layer thickness of the top Gallium Indium Phosphide (GaInP) in double junction solar cells decreases, the efficiency increases. Meanwhile, increasing the n-doped GaAs layer thickness will lead to slight increases in cell efficiency. However, the limitation would be the practical cost of utilising high layer thickness in exchange for a slight increase in high efficiency. The range of thickness from 500 nm to 3500 nm, which gives a variation in the efficiency of approximately 1.3%. However, the simulation results have shown, the temperature increase will lower the efficiency of the solar cell. In double-junction cells, the thickness variation of p-GaInP and n-GaInP significantly change the efficiency of the solar cell. The optimisation achieved here indicates some model structures for practical usage to achieve high-efficiency GaAs based on solar cells.

Two spectral emission lines originated from band splitting in Indium Phosphide nanotubes are observed experimentally. The nanotubes are grown by Metal-Organic Chemical Vapour Deposition on patterned template developed by electron beam lithography. The splitting effect arising from spatial confinement-induced momentum quantization on the band structure of nanotubes is investigated by developing a theoretical model. The incorporation of momentum quantization in sp3s*-model with spin-orbit coupling indicates the splitting of Γ-point into two different symmetric points, which emit two spectral lines as confirmed by cathodoluminescence spectra. The observation provides novel insight into the band structure based transport behaviour of semiconductor quantum devices.

We report the formation of an indium phosphide quantum dot/1-octadecene polymer composites by in situ polymerization and their improved properties in white LED (WLED) applications. The in situ polymerization process is very simple and efficient because the monomer is octadecene solvent, and hence, the composite was easily obtained. The quantum dots inside the composite are effectively passivated, and their stability is significantly improved. The WLED device with OE-6630 as an encapsulant shows an external quantum efficiency (EQE) of 160 lm W −1 and a color rendering index (CRI) of 90. Additionally, neutral (∼6000 K) and warm white light (∼3400 K) can be obtained by controlling the ratio of red-to-green quantum dots. Compared to a quantum dots-only system, the quantum dots/polymer composite shows significantly improved color rendering index (CRI) and external quantum efficiency (EQE) in the similar correlated color temperature (CCT) and color coordination. We expect that this new approach, based on our research, can be extended to many other applications.

Polymers hold the promise for ultra-fast modulation of optical signals due to their potential for ultra-fast electro-optic (EO) response and high EO coefficient. In this work, we present the basic structure and properties of an efficient EO material system, and we summarize the efforts made within the project ICT-POLYSYS for the development of high-speed transmitters based on this system. More specifically, we describe successful efforts for the monolithic integration of multi-mode interference (MMI) couplers and Bragg-gratings (BGs) along with Mach–Zehnder modulators (MZMs) on this platform, and for the hybrid integration of InP active elements in the form of laser diodes (LDs) and gain chips (GCs). Using these integration techniques and the combination of the hybrid optical chips with ultra-fast indium phosphide double heterojunction bipolar transistor (InP-DHBT) electronics, we develop and fully package a single 100 Gb/s transmitter and a 2×100 Gb/s transmitter that can support serial operation at this rate with conventional non-return-to-zero on-off-keying (NRZ-OOK) modulation format. We also present the experimental evaluation of the devices, validating the efficiency of the monolithic and hybrid integration concepts and confirming the potential of this technology for single-lane 100 Gb/s optical connectivity in data-center network environments. Results from transmission experiments to this end include the achievement of BER close to 6·10 −9 in B2B configuration, the achievement of BER lower than 10 −7 for propagation over standard single-mode fiber (SSMF) with total length up to 1000 m, and the achievement of BER at the level of 10 −5 after 1625 m of SSMF. Finally, plans for the use of the EO polymer system in a more complex hybrid integration platform for high-flexibility/high-capacity transmitters are also outlined.

Spin-polarized currents in double-barrier magnetic tunnel junctions (MTJs) as CoFeB/MgO/InP/MgO/CoFeB (MTJs-InP) are investigated by non-equilibrium Green’s function formalism. The asymmetric structures with a half-metal LSMO contact are studied and a spin-diode behavior is found compared to the MTJs-InP. Charge and spin currents as well as spin polarization as a function of bias voltage, angle between magnetizations and quantum-well thickness are also described. A nearly 100% spin polarization is observed at a certain range of bias voltage. Therefore, one can design excellent spin-filter devices based on new MTJs-InP.

In this paper, a novel double gate Spin-Field Effect Transistor (DG spin-FET) with indium phosphide (InP) as channel material is evaluated. The proposed spin-FET device is well suited for CMOS technology, as both n and p-type devices can be formed by using parallel and anti-parallel combinations of spin-FET respectively. The proposed device feature size is in sub 10 nm range and therefore is compatible with state of the art integrated circuit technology. The leakage currents have been reduced by employing high-k dielectric (HfO2). A comparative analysis of the proposed device with the devices reported in the literature confirm that the proposed device has improved on-off ratio and ON current. Besides the device has low transit time and less parasitic capacitances required for high frequency and low power applications respectively.

The temperature dependencies of the heat capacity and thermal expansion of gallium arsenide, indium arsenide, indium phosphide, and (GaAs) 0.2 (InAs) 0.8 solid solutions were analyzed by Einstein–Debye approximation. A simple model of the phonon spectrum of the substances is suggested. This model allowed us to establish the causes of the anomalous behavior of the thermal characteristics of the substances at low temperature.

The band structure and electronic transport property of InP nanotube molecular device are studied using density functional theory with GGA/PBE exchange correlation functional. The substitution of nitrogen in InP nanotube slightly widens the band gap. The substitution of nitrogen and aluminium in InP nanostructure modifies the density of states across InP nanotube. The electron density is found to be more on phosphorus sites than indium sites. The substitution of aluminium increases the electron density, whereas nitrogen substitution decreases the electron density across phosphorus site. The transmission spectrum provides the insight to transmission along InP nanotube molecular device. The transmission pathways get modified with the substitution impurity along InP nanotube molecular device. The results of the present work will give information on tuning the band structure and transport properties of InP nanotube molecular device.

Graphene based van der Waals heterostructure has attracted wide attention recently, especially for graphene/semiconductor Schottky junction. Herein, through delicately designing and engineering the van der Waals heterostructure between graphene and indium phosphide (InP), which has a suitable bandgap of 1.34 eV for solar energy conversion, we have achieved graphene/p-InP solar cells with power conversion efficiency (PCE) of 3.3% under AM 1.5G illumination. The chemical doping or electrical field modulation has been used to tune the Fermi level of graphene, which leads to a PCE of 5.6% for the device under gating effect. Furthermore, the interface recombination rate could be reduced while graphene is doped or gated, as evidenced by transient photoluminescence measurements. Considering the stability of cell performance under illumination and the high resistance to space irradiation damage of InP, graphene/InP heterojunction may be promising for special applications such as space solar cells.

Photon-enhanced thermionic emission (PETE) solar cells are photovoltaic devices designed for high temperature operation. The use of Si, GaAs, and InP as the cathode (i.e. the absorber and the electron-emitter electrode) materials in PETE solar cells is investigated with numerical device models. The models describe the cathode one dimensionally and are valid also at high injection levels. The temperature dependence of the photon absorption coefficients and temperature and doping dependencies of electron mobilities are modelled. Simulated device characteristics are presented and the factors determining the efficiency of the PETE devices are discussed. Our results show that Si, GaAs, and InP are all promising materials for PETE solar cells, if the surface recombination, effective electron affinities, and thermal stability of these materials can be optimized. Owing to their strong absorption, GaAs and InP show higher efficiencies (20–25%) than Si (10–15%) in spite of their intense radiative recombination. Especially, InP is a promising candidate for PETE cathodes as it shows higher efficiency than GaAs due to its stronger photon absorption properties.

Non-linear optical properties of indium gallium aluminum arsenic/indium phosphide (InGaAlAs/InP) material system based unstrained and strained lasing nano-heterostructures of straddled type (type-I) under TE (transverse electric) polarization mode have been studied. To produce the different states of strain at the heterointerfaces in the structure, the different layers of the active region of InGaAlAs (width ~6 nm) with different lattice constants (due to different mole fractions) have been assumed to be deposited in between the barriers of In0.41Ga0.34Al0.25As followed by claddings of In0.52Al0.48As. The entire nano-structure is a type of step SCH (separate confinement heterostructure) and has been assumed to grow over InP substrate. To study the strain induced non-linear optical properties of the structure, single effective mass and Kohn–Luttinger Hamiltonian equations have been solved to obtain quantum states and envelope wave functions in the heterostructure. In addition, the optical gain, differential gain, and the anti-guiding factor in order to support the gain calculation have been computed and reported. On behalf of simulation and previously reported experimental results, it has been suggested that either unstrained or compressive strained InGaAlAs/InP nano-heterostructures are more suitable for novel applications in the emerging areas of nano-opto-electronics due to the maximum gain occurring at lasing wavelength of 1.55 µm which is the wavelength of minimum optical attenuation.

The admittance measurements which include the capacitance–voltage ( C – V ) and conductance–voltage ( G / ω – V ) characteristics of gold/p-type indium phosphide (Au/p-InP) Schottky barrier diodes (SBDs) were conducted by taking into account the interface states ( N ss ) and series resistance ( R s ) effects in the temperature range of 80–320 K with a steps of 20 K. Experimental results confirm that the N ss and R s are important parameters which strongly influence the main electrical parameters of SBD. The C–V plots for each temperature exhibit the increasing behaviour in depletion region and then give an anomalous peak such that peak position shifts toward positive bias region with increasing temperature due to the re-structuring and re-ordering of surface charge under the temperature effect and the existence of a series resistance ( R s ). In addition, C takes negative values in the inversion region at edge, which is known as negative capacitance (NC) behaviour. The effect of R s on the C – V plot is found considerably high at low temperatures in the accumulation region. Therefore, both the measured capacitance ( C m ) and conductance ( G m / ω ) were corrected to obtain the real diode capacitance ( C c ) and conductance ( G c / ω ). In addition, R s and N ss values decrease with increasing temperature. Such behaviour of R s and N ss can be attributed to the trap charges which have sufficient energy to escape from the traps located at gold/p-type indium phosphide (Au/p-InP) interface.

Two types of semiconductors, indium phosphide (InP) and silicon (Si), were separately grown on polycrystalline copper foils with the presence of gold colloidal particles. InP was grown with and without carbon deposition by metal organic chemical vapor deposition, and Si was grown with and without plasma enhanced chemical vapor deposition of carbon. While InP and Si grew as films on untreated copper foils, they were found to grow in the form of nanowires when copper foils were pre-treated with carbon. Structural analysis revealed that the grown InP nanowires were polycrystalline. In contrast, the grown Si nanowires were found to have core–shell structures with a monocrystalline core and a polycrystalline shell. Further analysis suggested that graphene was formed on the copper foils during the carbon deposition. Therefore, we concluded that the presence of graphene promoted the growth of InP and Si in the form of nanowires. The demonstration of growing semiconductor nanowires on copper foils could be a new path to integrate semiconductor and metal to provide a unique material platform for a wide range of devices.

Graphical abstractDisplay Omitted We experimentally investigated the sputtering yield of crystalline InP using focused Ga+ beam.An ultra-thin taper structure was fabricated with obtained sputtering yield and related dose range.The dimensions of the taper are 400µm by 35µm, with a horizontal slope of about 1:13,000.Optical characterization on the photonic device proved the efficiency of the taper patterning. Focused ion beam milling has been applied to fabricate an ultra-thin taper structure on crystalline indium phosphide to realize a multi-wavelength vertical cavity photonic device. The appropriate FIB scanning procedures and operating parameters were used to control the target material re-deposition and to minimize the surface roughness of the milled area. The sputtering yield of crystalline indium phosphide target was determined by investigating the relationship between milling depth and ion dose. By applying the optimal experimentally obtained yield and related dose range, we have fabricated an ultra-thin taper structure whose etch depths are precisely and progressively tapered from 25nm to 55nm, with a horizontal slope of about 1:13,000. The optical characterization of this tapered device confirms the expected multi-wavelength behavior of our device and shows that the optical losses induced by the FIB milling process are negligible.

Indium phosphide and silicon play important and complementary roles in communications wavelength photonic devices. Realizing high quality coalesced epitaxial lateral overgrown (ELO) InP films on Si could greatly reduce cost and encourage the proliferation of energy efficient photonic integrated circuits in consumer devices. By adjusting a parallel line ELO mask and metalorganic vapor phase epitaxial growth conditions, we have fully coalesced and partially coalesced epitaxial lateral overgrowth of InP on InP substrates and Si substrates having strain relaxed III/V buffer layers, respectively. Extended defects were investigated using transmission electron microscopy and were not found to originate at the coalescence of the nearest neighbor growth fronts for linear parallel growth windows oriented 60° off of [0−11] when using a high V/III ratio of 406. In addition, narrowly separated linear parallel growth windows having a large aspect ratio of 7.5 were seen to inhibit the upward propagation of stacking faults through several neighboring openings. Elimination of these two defect sources would leave primarily the challenge of optimizing the morphology of the overgrown InP as a substantial barrier to achieving coalesced ELO InP of sufficient quality for photonic device applications.

Indium phosphide (InP) nanoneedles and nanotubes have been successfully synthesized by a solvothermal route. The detail morphology and crystalline structures of the products have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The possible growth mechanisms of InP nanoneedles and nanotubes are briefly discussed. The present InP nanoneedles and nanotubes may have important applications in advanced nanodevices.

The effect of polyvinylidene fluoride (PVDF) polymer interlayer on the rectifying junction parameters of Au/n-InP Schottky diode has been investigated using current–voltage (I–V) and capacitance–voltage (C–V) measurements at room temperature. The calculated barrier heights (BHs) are 0.57 eV (I–V), 0.72 eV (C–V) and 0.73 eV (I–V), 0.88 eV (C–V) for the Au/n-InP and Au/PVDF/n-InP Schottky diodes, respectively. Results showed that the BH of the Au/PVDF/n-InP Schottky diode is higher than that of the Au/n-InP Schottky diode, and that the PVDF film increases the effective BH by influencing the space charge region of the n-type InP. The values of the barrier height, ideality factors and series resistance estimated by I–V, Cheung's and Norde methods are compared. Experimental results showed that the interface state density of the Au/PVDF/n-InP Schottky diode is lower than that of the Au/n-InP Schottky diode. Further, the reverse leakage current conduction mechanism is investigated. Schottky emission mechanism is found to dominate the reverse leakage current in the Au/n-InP Schottky diode. However, for the Au/PVDF/n-InP Schottky diode, the Schottky conduction mechanism is found to be dominant in the higher bias region, whereas the Poole–Frenkel conduction is found to be dominant in the lower bias region. Apart from that, the discrepancy between BHs determined from I–V and C–V techniques is explained. Besides, the capacitance–frequency (C–f) and conductance–frequency (G–f) characteristics of the Au/PVDF/n-InP Schottky diode are discussed.

The fabrication of an InGaAs n-channel in complementary metal oxide semiconductors (CMOS) requires an intervening layer of Indium Phosphide (InP) that should be planarized using chemical mechanical planarization (CMP) before deposition of the InGaAs layer. The InP CMP process has to provide good InP removal rates (RRs) (100-200nmmin^-^1), very low oxide loss, low dishing and minimal or no phosphine evolution. In this work, it is shown that aqueous slurries containing 3wt% silica, 1wt% hydrogen peroxide and 0.08M oxalic acid or citric acid satisfy these requirements. Cross-sectional scanning electron microscope (SEM) images showed that InP in the shallow trench isolation structures was planarized and scratches, slurry particles and smearing of InP on the wafers were absent. Additionally, wafers polished at pH 6 showed very low dishing values of about 12-15nm, determined by cross-sectional SEM.

We present a study of indium phosphide nanowires grown by the selective area vapor liquid solid technique using metalorganic molecular beam epitaxy. Transmission electron microscopy revealed that nanowires grown at a temperature of up to 450 °C had a pure wurtzite structure, but at 480 °C a mixed wurtzite–zincblend structure was obtained. We also accurately measured the migration length of growth precursors along the side facets of the nanowires by monitoring the length of the non-tapered section of the nanowire adjacent to the gold catalyst. The migration length was found to be of the order of 0.3–0.7 µm and to depend on the diameter of the nanowire. Up to the growth temperature of 450 °C the migration length was temperature independent, but it increased dramatically to more than 2 µm when the nanowires were grown at 480 °C. Possible explanations for the observed effects are suggested.

We report on surface pretreatment for ohmic contacts to p-doped In0.53Ga0.47 As with improved thermal stability. It is found that the cleaning of In0.53Ga0.47 As surface by ammonium sulfide or sulfuric acid offers the optimum surface treatment prior to metal deposition. Contacts using an iridium contact layer and palladium diffusion barrier were fabricated and compared to a conventional platinum-based contact Pt/Ti/Pt/Au. Pt-based metal stack suffered from void formation and high reactivity with the semiconductor when annealed at 240 °C for a few hours, as examined by transmission electron microscopy. As a result, the Pt-based stack exhibited strong deterioration of the resistivity. On the other hand, the Ir contact maintained its integrity during thermal stress. The improved contact exhibited a void and reaction-free microstructure and offered stable resistivity values with annealing.

This paper treats the impact of post growth tuned InAs/InP quantum dashes' (QDas) size/composition distribution on carriers' localization and thermal redistribution. The spread of this distribution depends on the experimental conditions used for the phosphorus ion implantation enhanced intermixing process. Atypical temperature-dependent luminescence properties have been observed and found to be strongly dependent on the amount of QDas size/composition dispersion. The experimental results have been reproduced by a model that takes into account the width of the QDas localized states distribution and consequent thermally induced carriers' redistribution. This model gives critical temperature values marking the beginning and the end of carriers delocalization and thermal transfer processes via an intermixing induced carrier's transfer channel located below the wetting layer states.

We report photoluminescence (PL) of indium phosphide (InP) surface passivated by sulfur (S). A three-fold enhancement of band edge emission from the bulk InP was observed after the InP was passivated by ammonium sulfide ((NH4)2S) solution for 10 min. X-ray photoelectron spectroscopy measurements indicate that the oxide at InP surface is removed after being sulfurized in (NH4)2S solution. However, the enhancement significantly decreases for a longer treatment time, which is maybe due to a thick S layer deposited at the InP surface resulting in low light transmission.

Selective area growth (SAG) of single crystalline indium phosphide (InP) nanopillars was demonstrated on an array of template segments composed of a stack of gold and amorphous silicon. The template segments were patterned by UV nanoimprint lithography on a silicon substrate covered with a natural oxide, and the SAG was achieved by metal organic chemical vapor deposition. Our SAG is different from conventional SAG in one critical aspect. In our SAG, growth of InP takes place selectively on a pre-defined array of template segments made of non-single crystal materials on a foreign substrate. The grown InP nanopillars were studied for their structural, chemical and optical properties. The new SAG process is not limited to the specific materials such as InP nanopillars and silicon substrate used in this demonstration; our approach enables flexible and scalable nanofabrication using industrially proven tools and a wide range of semiconductors on various non-semiconductor substrates.

Two-step high-pressure sputtering for Gd2O3 deposition on InP substrates.Working MIS devices for all sputtering and plasma oxidation conditions.High capacitance (CET of 2.4nm) with moderate leakage (under 10-3Acm-2 at a gate voltage of 1V). We show working metal-insulator-semiconductor devices fabricated on InP with high-k gadolinium oxide deposited by a two-step high-pressure sputtering procedure. Functional devices are obtained in all cases, with a full accumulation-depletion-inversion sweep. An intermixing of the Gd2O3 with the Pt/Al gate was found, which limited accumulation capacitance. After changing the process to pure Pt gates, the accumulation capacitance increased by a factor of ~2. The devices show an unpinned Fermi level and moderate leakages, although there is a high level of interfacial traps. These traps are not passivated after a soak anneal at 325?C.

Due to the low density states and high radiative efficiency, quasi-zero-dimensional quantum dot has already exposited major new advances in both fundamental physics and device applications. In this paper we concentrated on the recent developments of the InAs/InP system quantum dot lasers, operating nearby the important fiber communication system of 1.55 μm. In all cases, we stressed the significant progress in the understanding of basic optical and electronic properties to enable the importance steps forward. The developments have been almost covered the important advances for both large ensembles and for individual quantum dots devices, emphasizing the versatility of these systems in opening up a variety of new phenomena. The prospects for further progress directed towards new quantum dot laser for 2–3 μm, stability of single frequency operation with wide tunable range and single photon source are also described.

Water-soluble fluorescent probe based indium phosphide quantum wires decorated with 6-mercaptohexanoic acid has been particularly designed to monitor cyanide ions at very low concentrations up to 110 pM. 6-Mercaptohexanoic acid capped InP quantum wires were prepared by water based route technique at low temperature for the first time. At optimum condition, the emission intensity was found proportional to the concentration of cyanide ions in the range of 0–110 × 10 −12 mol L −1 with detection limit 2.1 × 10 −15 mol L −1 . The results showed the probe has a prominent dynamic sensing range making it promising candidates for human safeguard enforcements. The emission spectrum of the functionalized quantum wire probe working in the blood and tissues optical window ( λ = 750 ± 10 nm). This enables the prepared functionalized quantum wire to be used for transdermal blood monitoring or even for the enumeration of cyanide levels in fire victims.

International audience; A time resolved study of the behavior of a single beam in photorefractive iron doped indium phosphide is provided down to the microsecond range, showing that infrared beam bending does occur on the microsecond time scale for moderate beam intensities. Two distinct time scales are evidenced, the behavior of which are the sign of two different photorefractive mechanisms.

Indium phosphide semiconductor quantum dots are of significant heed as their applications encompass a spacious concatenation in LEDs and solar cells technologies. For improving their serviceable prominence, there is a real demand for a fashion that furnishes prompt and large mass production of mightily monodispersed nanoparticles. This study conveys an efficacious and fast recipe of generating substantially monodispersed InP quantum dots via water based route technique using a novel surfactant. Herein, InP QDs have been prepared using 6-mercaptohexanoic acid for achieving an effective surface passivation of monodispersed InP QDs with highly luminescence at temperature 50 °C. The as prepared quantum dots were investigated by transmission electron microscopy, luminescence spectroscopy, and X-ray diffraction. The XRD depicted that the InP quantum dots have a cubic zinc blend structure. TEM image revealed that the prepared quantum dots are monodispersed and their average particle size of about 4 nm. Energy dispersive X-ray spectroscopy confirmed the existence of organic ligand as a shell around InP nanoparticles. Time resolved spectra depicted that the capping agent passivated the InP QDs surface and enhanced the luminescence emission.

Urchin-like InP architectures were synthesized by hydrothermal route at 160 °C. The products were characterized with scanning electron microscopy, X-ray diffraction, spectrofluorometry. Results show that the hollow urchin-like InP microspheres with diameters of 40–70 μm were composed by numerous microrods with a diameter of about 0.5–2 μm. The obtained InP samples were of high purity zinc blende (cubic) structure. According to the analysis on the effects of reaction time on the morphologies, a possible formation mechanism of hollow urchin-like InP architectures was proposed. The optical properties of the urchin-like InP hollow microspheres were also investigated at room temperature, and results show that the urchin-shape InP microspheres displayed a strong emission at 599 nm, which is quite different from that observed in all previous reports related to the InP nano/micro structures.

Indium phosphide (InP) films were deposited onto glass substrates using RF magnetron sputtering by varying the substrate temperature (348–573 K), under constant argon pressure (0.4 Pa) and RF power (150 W). Substrate temperature found to have significant influence on the composition, structure, morphology, electrical and optical properties of InP films. Single phase, nearly stoichiometric and polycrystalline films exhibiting zinc blende structure with strong preferred orientation along (111), was observed for the films grown at a substrate temperature of 448 K. Conical shaped grain growth was observed in the grown films. Hall measurements revealed n-type conductivity in the InP films. The optical absorption studies indicated a direct band gap of 1.35 eV. Various lattice vibrational modes observed by Raman measurements were found to match well with those reported for single-crystal InP.