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Novel back-illuminated modified uni-traveling- carrier photodiodes (MUTC-PDs) are reported to demonstrate wide bandwidth and high output power performance at D-band (110–170 GHz) regime. A comprehensive design model is employed to predict and tune the frequency response by incorporating coplanar waveguides (CPWs) with different inductive peaking effects. As a demonstration, 4.5-μm-diameter photodiodes with two types of CPWs are fabricated to exhibit different frequency response profiles. Both PDs exhibit a 3-dB bandwidth over 150 GHz and the measured frequency responses are in excellent agreement with simulations. Thanks to the proper design of the CPW electrodes, the two PDs exhibit an output power roll-off of only 4.3 dB and 4.8 dB from dc to 170 GHz, respectively, and high saturation performance is maintained over the broadband frequency range of 130–170 GHz.

An indium phosphide photonic integrated circuit (PIC) was demonstrated for integrated path differential absorption lidar of atmospheric carbon dioxide (CO2). The PIC consists of two widely tunable sampled grating distributed Bragg reflector (SGDBR) lasers, directional couplers, a phase modulator, a photodiode, and semiconductor optical amplifiers (SOAs). One SGDBR laser, the leader, is locked to the center of an absorption line at 1572.335 nm using the on-chip phase modulator and a bench-top CO2 Herriott reference cell. The other SGDBR laser, the follower, is stepped in frequency over ±15 GHz around 1572.335 nm to scan the target CO2 absorption line. The follower laser is offset locked to the leader laser with an optical phase lock loop. An SOA after the follower laser generates a pulse at each frequency step to create a train of pulses that samples the target CO2 absorption line. The PIC components and subsystem are characterized and evaluated based on target performance requirements. The leader laser demonstrated a 236-fold improvement in frequency stability standard deviation when locked compared to free running and the follower laser frequency stability standard deviation compared to the leader laser was 37.6 KHz at a 2 GHz programmed offset.

A terahertz (THz) fundamental oscillator IC with high efficiency and compact chip size based on an indium phosphide (InP)-based resonant tunneling diode (RTD) is proposed. The oscillator is designed by utilizing a low-frequency bias stabilizer, along with utilizing a negative differential resistance oscillator topology. The oscillator is fabricated by using an InP monolithic THz integrated circuit multilayer process. The fabricated oscillator shows a high dc-to-RF power efficiency ( η ) of 0.274 % with a low dc power consumption of 3.4 mW and an RF output power of 9.3 μ W at an oscillation frequency of 692 GHz. The IC exhibits a chip size of 300 × 380 μ m2 excluding the measurement pads. The achieved η and chip size are good values among THz oscillators above 500 GHz reported to date.

High-speed and robust optical beam-steering device will be the key component for various applications, such as LiDAR (light detection and ranging) and free-space optical communication. Optical phased arrays (OPAs) integrated on semiconductor chips have recently received increasing attention due to the high-speed operation, compactness, and low cost. In particular, indium phosphide (InP)-based OPAs are advantageous for high-output-power applications at 1.55- $\mu \text{m}$ eye-safe wavelength, owing to their capability of monolithically integrating active components, such as high-power lasers and optical amplifiers. In this letter, we design and fabricate, to the best of our knowledge, the largest-scale InP-based OPA and experimentally demonstrate its beam-steering operations. The fabricated OPA consists of 100 waveguides with carrier-injection-based phase shifters, densely integrated on 7 mm $\times5$ mm footprint. A focused beam width of 0.11° is steered across the free spectral range of 8.88°, corresponding to more than 80 resolvable points. This is the largest number of resolvable points obtained by a monolithic InP OPA. The response time of the OPA is confirmed to be less than 16 ns, which is limited by the driver circuit. This work paves the way for realizing compact beam-steering modules for high-speed and high-output-power imaging applications.

Avalanche photodiodes (APDs) are used in optical receivers of high-speed optical communication systems to improve signal-to-noise ratio over conventional photodiodes. Low excess noise characteristics are crucial for APDs to preserve the benefits associated with high internal gains. In this work, we presented room temperature data of avalanche gain and excess noise factors of Al0.85Ga0.15As0.56Sb0.44 APDs using pure and mixed carrier injection profiles. Using pure electron injection, the best possible excess noise performance for a given avalanche width was measured with an excess noise factor https://doi.org/10.15131/shef.data.15082455 )

A photoreceiver consisting of indium phosphide (InP) balanced photodiodes (PD) on Si $_3$ N $_4$ waveguides and a transimpedance amplifier (TIA) fabricated in a silicon germanium (SiGe) BiCMOS process is demonstrated. The InP PDs, heterogeneously integrated on a silicon substrate, achieve external (internal) responsivities of 0.75 (0.9) A/W, bandwidths of 4 GHz, and common mode rejection ratios (CMRR) of greater than 40 dB when illuminated differentially. The TIA achieves 74 dB $\bf \Omega$ of transimpedance gain with a 1 dB peak, a bandwidth of 3 GHz, and a low equivalent input noise current density of 7.2 pA/ $\sqrt{Hz}$ when loaded with a C $_{PD}$ of 380 fF. The full photoreceiver achieves high conversion gain of more than 2 kV/W up through 2 GHz, and a low NEP of 8 pW/ $\sqrt{Hz}$ up through 1.6 GHz. The photoreceiver optical CMRR is measured to be 36 dB.

High resolution and wide color gamut are two key requirements for novel display technologies. Owing to the distinguishing advantages over conventional displays, such as intrinsic wide color gamut and the possibility to achieve high resolution, quantum dot light-emitting diodes (QLED) have drawn considerable attention in recent years. On the other hand, indium phosphide quantum dots (InP QDs) have shown a great potential as a replacement for cadmium selenide (CdSe) QDs in display applications due to the inherent toxicity of cadmium-based QDs. In this study, we investigate a top-emission InP-based green QLED with optimized angular distribution. By adjusting the electrical and optical architecture, the device exhibits improved properties with a maximum current efficiency of 30.1 cd/A and a narrowed full width at half maxima (FWHM)of 31 nm, which are the best results ever reported to our knowledge.

The effect of atomic-layer-deposition (ALD)-derived Al2O3 passivation layer on the interface quality of Er2O3/Al2O3/InP laminated stacks and the improvement of electrical performance has been investigated systematically. The chemical bonding states measured by high-resolution X-ray photoelectron spectroscopy (XPS) reveal that the ALD-derived Al2O3 passivation layer can effectively inhibit the diffusion of substrate elements to optimize the interface quality. Electrical characterizations show that the optimized sample has demonstrated improved electrical properties, including the large dielectric constant of 20 and the suppressed leakage current density of $4.10\times 10^{-7}$ cm2. In addition, the leakage current conduction mechanisms are also investigated as a function of thickness of Al2O3 passivation layer. The optimized interface state density extracted from the conductance method has reduced from $1.30 \times 10^{12}$ eV−1cm2 of Er2O3/InP to $7.27 \times 10^{11}$ eV−1cm2 of Er2O3/Al2O3/InP by adjusting the passivation layer thickness. As a result, it can be also confirmed that the passivation treatment is beneficial to inhibit the element’s diffusion and optimize the interface quality, significantly controlling the capacitor degradation caused by the leakage current through the stacked oxide layer.

We report uniform Type-II GaInAsSb/InP UTC-PDs, and compare their performance to devices fabricated with GaAsSb uniform and graded (composition and doping) absorbers of the same thickness. The quaternary UTC-PDs show a transit limited bandwidth of 274 GHz in contrast to 107 and 185 GHz for uniform and graded GaAsSb absorber UTC-PDs. Because the uniform quaternary and ternary UTC-PDs only differ in their absorber material, the findings conclusively demonstrate enhanced transport in GaInAsSb. Performance comparison to GaInAs-based devices from the literature suggest that GaInAsSb is a superior absorber material for λ = 1.55 μm high-speed photodetectors. Additionally, the external responsivity of the GaInAsSb UTC-PDs (0.094 A/W) is ~34% higher than the GaAsSb PDs (0.070 A/W). This is the first demonstration of a quaternary GaInAsSb absorber in UTC-PDs., Journal of Lightwave Technology, 39 (7), ISSN:0733-8724, ISSN:1558-2213

Single photon avalanche diodes (SPADs) are key enabling technologies for a wide range of applications in the near-infrared wavelength range. Recently, AlAs0.56 Sb0.44 (hereafter AlAsSb) lattice-matched to InP has been demonstrated for extremely low excess noise avalanche photodiodes (APDs) due to its large disparity between electron and hole ionization coefficients ( $\alpha $ and $\beta $ respectively). The $\alpha /\beta $ ratio also plays a role in Geiger mode operation as it affects the avalanche breakdown probability and hence detection efficiency. In this work, we theoretically investigate the performance of AlAsSb based SPADs. The probability of breakdown for electron-initiated Geiger mode operation increases more sharply with multiplication region width due to progressively more dissimilar ionization coefficients. In comparison with other common avalanche materials, such as InAlAs, InP and Si, our result also suggests that SPADs based on AlAsSb have a sharper breakdown probability than the other three materials under similar low overbias ratio. The calculated breakdown probability of 0.81 in AlAsSb is 0.18 and 0.28 higher than that of InAlAs/Si and InP respectively at 5% overbias ratio and with avalanche region width of 1500 nm.

A mono-bit digital receiver circuit for instantaneous frequency measurement is presented. The circuit is co-designed with Indium Phosphide Double Heterojunction Bipolar Transistor and complementary metal oxide semiconductor (CMOS) devices. The chip is fabricated by InP/CMOS three-dimensional (3D) heterogeneous integration using the wafer-level bonding technique. The measurable signal frequency within + 15 to − 25 dBm power is up to 7.5 GHz with a 14-GHz clock. Compared to an integrated circuit (IC) with a traditional InP or CMOS technologies, the proposed chip could benefit from both InP and CMOS technology. In the heterogeneous integration, InP devices provide high operating frequency, broad signal bandwidth, and large input signal dynamic range, while CMOS devices achieve complex function with low power consumption. In this way, the system FoM is improved for a mono-bit digital receiver while the system power consumption is kept the same. This work also shows the great potential of the 3D heterogeneous integration for the high-performance mixed-signal and multifunction radio-frequency ICs.

Epitaxially integrating III-V lasers with Si-photonics is the key for compact, efficient, and scalable photonic integrated circuits (PICs). Here we present an investigation of a path forward in integrating III-V functionalities on industry-standard silicon-on-insulator (SOI) platforms using selective area hetero-epitaxy. Based on our recently developed methods of selectively growing device quality InP on (001)-oriented SOI wafers, we demonstrated InP stripes and segments, with dimensions varying from a few hundred nanometers to a few micrometers. The flexible epitaxy of InP on SOI together with the unique “bufferless” trait will enable efficient light interfacing with Si-based photonic devices using either evanescent or butt coupling schemes. We simulated the possibility of employing the micrometer-scale InP on insulator to realize electrically driven lasers and found that the metal induced optical loss is negligible when the InP dimension exceeds 4.0 μm. The potential of utilizing this selective area growth method to realize fully integrated Si-photonics is illustrated.

This article reports a detailed approach toward optimization of on-wafer thru-reflect-line (TRL) calibration structures for submillimeter-wave characterization of a state-of-the-art indium-phosphide (InP) technology, validated by thorough experimentation and electromagnetic (EM) simulation. The limitations of the existing RF test structures for high-frequency measurements beyond 110 GHz are analyzed through EM simulation. Using an optimization procedure based on calibration of raw EM simulated data, on-wafer TRL calibration structures were developed and fabricated in a subsequent run of this technology. Measurements could be achieved up to 500 GHz on the passive devices and up to 330 GHz on the InP double heterojunction bipolar transistors (DHBTs). The transistor measurements were validated by comparison with the HiCuM compact model simulation to 330 GHz for the InP DHBTs.

Here, we report efficient and stable indium phosphide (InP) based inverted red quantum dot light-emitting diodes (QLEDs) using a new high mobility and deep HOMO level hole transport layer (HTL) and...

In this study, multishelled InP-based quantum dots (QDs) were synthesized using a phosphorus source tris(dimethylamino)phosphine [(DMA)3P] and were applied to solution-processed QD light-emitting d...

Most recently, III–V based ultrathin solar cells have attracted considerable attention for their inherent advantages, such as increased tolerance to defect recombination, efficient charge carrier separation, photon recycling, flexibility, and reduced material consumption. However, so far, almost all reported devices make use of conventional doped p-i-n kind of structures with a wide-bandgap III–V lattice-matched epitaxial window layer, for passivation and reduced contact recombination. Here, we show that a high-efficiency device can be obtained utilizing an InP thin film of thickness as low as 280 nm, without the requirement of a conventional p-n homojunction or epitaxial window layer. This is achieved by utilizing a wide-bandgap electron and hole selective contacts for electrons and holes transport, respectively. Under ideal conditions [assuming interface recombination velocity (IRV) = 103 cm/s and bulk lifetime = 1 μs], the proposed solar cell structure can achieve efficiency as high as 28%. Although, in the presence of bulk and interface Shockley–Read–Hall recombination, the efficiency reduces, still for bulk minority carrier lifetime as low as 2 ns and an IRV as high as 105 cm/s, an efficiency of ∼22% can be achieved with InP thickness as low as 280 nm. The proposed device structure will be beneficial in cases where the growth of controlled p-n homojunction and window layer can be tedious as in case of low-cost deposition techniques, such as thin-film vapour–liquid–solid and close-spaced vapour transport.

This article describes the design and performance of a 140-GHz SiGe and a 100-GHz InP triple-stacked HBT distributed amplifier with active bias terminations. The active bias network is configured to extend the practical low-frequency operation while maintaining gain flatness and linearity. Triple-stacked HBTs are used to increase the gain–bandwidth and linear output capability. The SiGe design is based on HBTs with a peak $f_{\mathrm {T}}/f_{\mathrm {max}}$ of 300/350 GHz and achieves 11.7 dB of gain and a bandwidth from baseband to 140 GHz. The InP HBT design is based on DHBTs with a peak $f_{\mathrm {T}}/f_{\mathrm {max}}$ of 250/250 GHz and obtains a gain of 10.8 dB and a bandwidth of 100 GHz. Although the SiGe design achieves 1.5 times higher gain–bandwidth, the InP DHBT design achieves ~3–4.5 dB greater IP3, $P_{\mathrm {1~dB}}$ , and $P_{\mathrm {3 ~dB}}$ while consuming only ~23% higher dc power. These results represent the first broadband performance comparison of near-identical (apples–apples) DA designs implemented in SiGe and InP HBT device technologies. Although there are previous reports of larger bandwidth distributed amplifiers in both InP and SiGe technologies demonstrated up through 200 GHz, the InP and SiGe monolithic microwave integrated circuits (MMICs) described in this article are believed to represent the highest bandwidths reported for HBT DAs using practical on-chip active bias terminations.

The use of epitaxial regrowth of InP on lattice-matched In0.53Ga0.47 As for passivation of photodiodes lateral mesa surfaces is investigated. The effect of the regrown layer was examined by photoluminescence and dark current measurements and compared with results obtained with SiO2 and Al2O3 passivation layers. The integrated intensity of steady-state photoluminescence of InGaAs covered by InP increased by a factor between 15.5 and 58.9, depending on the excitation wavelength, denoting a strong reduction of nonradiative recombination. This reduction is expected to be the result of a strong reduction of intragap surface states. For the same photoluminescence measurements, both SiO2 and Al2O3 oxide passivation instead showed a reduction of the photoluminescence intensity. The dark currents of p-i-n photodiodes showed less striking results, a fact that we claim, probably is related to residual doping of the InP regrown layer.

Among the III-V semiconductor materials, indium arsenide (InAs) nanowire (NWs) with high carrier mobility are expected to be alternative channels for high-performance and low-power field-effect transistors (FETs). However, there is a challenge in enhancing the on-state current for the InAs NW-channel vertical gate-all-around (VGAA) structures on Si. We investigated vertical InAs/InP core-shell (CS) NW-channels to enhance the current and demonstrated InAs/InP CS NW VGAA FETs. The InAs/InP CS NW-channel enhanced the on-state current while maintaining a small off-leakage current. The devices showed an on-state current of 40 $\mu \text{A}/\mu \text{m}$ , off-leakage current of 1 pA/ $\mu \text{m}$ , and subthreshold slope of 111 mV/dec at $\text{V}_{\text {DS}} =0.50$ V. The origin of the current enhancement suggests that there is a formation of two-dimensional electron gas (2DEG) in the InAs/InP CS NW-channel, and the characteristics of the InAs/InP CS NW VGAA FET revealed that the InP interlayer at draian edge and low source resistivity are important parameters to take advantage of 2DEG for CS NW VGAA FET.

We present a novel photonic integrated circuit (PIC) that monolithically integrates a racetrack colliding-pulse mode-locked laser with a pulse-picking electro-absorption modulator and a semiconductor optical amplifier on Indium Phosphide. We present detailed characterization of this PIC that includes optical pulse characterization, phase noise and long term stability under passive and hybrid mode-locking conditions. Allan deviation measurements made on the optical pulse train from the PIC show a fractional frequency instability of $8\times 10 ^{-11}$ at 1 second and follow a 1/ $\tau $ trend. We also demonstrate repetition rate reduction from ~10 GHz to ~500 MHz with an extinction ratio of ~14.65 dB using an on-chip pulse-picking electro-absorption modulator.

In this article, for the first time, a hybrid plasmonic (HP) ring resonator uni-traveling carrier pin-photodetector was numerically presented that offers a high responsivity of 0.68 A/W, a high bandwidth of over 125 GHz, and low footprint. This device has the capability of monolithic integration with HP-passive devices on the InP platform at an optical communication wavelength of 1550 nm.

This paper reports on a 100-nm gate length InP high-electron-mobility transistor (HEMT) technology for cryogenic low-noise amplifiers (LNAs) with ultra-low power dissipation of $112~\mu \text{W}$ . This result was obtained by using 100-nm gate length InP HEMTs with improved transconductance at low drain current through a scaled-down gate-channel distance while maintaining a low gate leakage current with the use of an InP etch stop layer and Pt gate metal. The noise performance of InP HEMTs was demonstrated in a 4–8 GHz (C–band) three-stage hybrid LNA at the ambient temperature of 5 K. At a dc power dissipation of $300~\mu \text{W}$ , the average noise temperature was 2.8 K with 27 dB gain. At a dc power dissipation of $112~\mu \text{W}$ , the LNA exhibited an average noise temperature of 4.1 K with a gain of 20 dB. The presented results demonstrate the large potential of InP HEMT technology for sub-mW cryogenic LNA design.

Photonic integrated circuits (PICs) suffer from birefringence due to high-index contrast. Polarisation handling devices improve the performance of the PICs by reducing the polarisation-dependent dispersion and loss. Furthermore, there is a growing interest in building polarisation division multiplexed transceivers using PICs, which require polarisation management. The authors provide an overview of the recent work on developing polarisation handling devices such as polarisation beam splitters and polarisers in indium phosphide and silicon-on-insulator platforms for optical communications and sensing applications. These devices expand the PICs library of polarisation handling devices and can be used to design more complex circuits with advanced or new functionalities.

The temperature characteristics of arched-cavity quantum-cascade lasers with different geometrical dimensions emitting in the spectral range of 7–8 μm are studied. The laser heterostructure was grown by molecular-beam epitaxy. The active region consisted of 50 cascades based on a heteropair of In0.53Ga0.47As/Al0.48In0.52As solid alloys. Single-mode lasing is demonstrated for lasers with the semicircular cavity segment 100 μm in diameter and the linear segment 1 mm long. The maximum side-mode suppression ratio at a temperature of 290 K was 26 dB, and the emission wavelength was 7.73 μm.

A wideband monolithic microwave/millimeter-wave integrated circuit (MMIC) distributed amplifier (DA) using a 3-D interdigital capacitor at the input of the gain cell is demonstrated in an indium phosphide (InP) heterojunction bipolar transistor (HBT) process. The proposed DA using interdigital capacitors improves the input return loss at high frequencies compared with the one implemented with conventional metal–insulator–metal (MIM) capacitors. The fabricated amplifier achieves a measured average gain of 10.5 dB over a 3-dB bandwidth from 1 to 160 GHz. The maximum measured saturated power ( $P_{\mathrm {sat}}$ ) is 17.8 dBm with the corresponding 1-dB compression power ( $P_{\mathrm {1\,dB}}$ ) of 15 dBm at 55 GHz. The amplifier achieves a minimum $P_{\mathrm {sat}}$ of 14.6 dBm up to 110 GHz.

The method of molecular-beam epitaxy was used to fabricate an elastically balanced heterostructure of a quantum-cascade laser for the spectral range of 4.6 μm based on a heteropair of solid alloys, In0.67Ga0.33As/In0.36Al0.64As, and indium phosphide layers serving as waveguide cladding layers. An X-ray diffraction analysis demonstrated the high uniformity of the composition and thickness of layers in cascades of the heterostructure over the substrate area. Lasers with four cleaved facets show lasing at room temperature at a wavelength close to 4.6 μm with a comparatively low threshold current density of 1.1 kA/cm2.

We report on the free-running and frequency stabilized operation of a ring resonator-tuned full-band tuneable laser. The laser is a monolithically integrated semiconductor ring laser tuneable over 34 nm, from 1522-1556 nm, fabricated using a commercially-available, InP-based, active-passive foundry technology. The mode selection is implemented using the Vernier effect by reverse-biasing voltage-controlled electro-optically tuned ring resonators. The laser exhibits a typical intrinsic linewidth of 110 kHz over the C-band and a side-mode suppression ratio (SMSR) exceeding 50 dB. The linewidth over the tuning range does not significantly vary, showing that the tuning mechanism does not cause linewidth broadening. The power dissipated in the tuning elements is 1.4 mW per ring. Using the same reverse bias voltage-controlled electro-optic tuning, we also demonstrate the locking of the laser to a high-finesse etalon using Poun-Drever-Hall frequency locking. Our implementation requires a single control loop because of the reverse bias tuning. All deployed tuning effects in the phase modulators have the same sign therefore resulting in a flatter frequency dependent phase response compared to current injection feedback. The control loop has a bandwidth of 500 kHz and a control range of 2.9 GHz. We report 1 kHz level linewidth for millisecond observation times for the stabilized laser.

Avalanche photodiodes (APDs), and single photon avalanche diodes (SPADs), with InP avalanche regions and InGaAs absorption regions, are used for detecting weak infrared light at ∼1.55 μm wavelength. These devices are often cooled to below room temperature during operation yet both validated simulation models and impact ionization coefficients that accurately describe the avalanche characteristics of InP are lacking in the temperature range of interest (200 K to room temperature). In this article we present an accessible, validated temperature dependent simulation model for InP APDs/SPADs. The model is capable of simulating avalanche gain, excess noise, breakdown voltage, and impulse current at 150–300 K. Temperature dependent ionization coefficients in InP, which may be used with other APD/SPAD simulation models, are also presented. The data reported in this article is available from the ORDA digital repository (DOI: 10.15131/shef.data.c.4373006).

In this work we have demonstrated a waveguide integrated uni-traveling carrier photodiode on an InP-membrane-on-silicon platform with 3 dB bandwidth beyond 110 GHz. With design optimization and an improved process, devices as small as $ \text{3}\times \text{2}\;\mu \text{m}^2$ are successfully realized. An electrical equivalent circuit model based on measured S-parameters revealed ultra-small series resistance and junction capacitance as low as 6.5 $\Omega$ and 4.4 fF, respectively, in the diodes. The model also provided insight in the photocurrent dependent characteristics in the bandwidth and resonsivity of the devices. Finally, data transmission measurements are demonstrated, showcasing the high speed telecommunication abilities of the UTC-PD.

A vertical bi-stable resistor (biristor) composed of In0.53Ga0.47As was demonstrated for sub-1 V operation. An inherent small bandgap and a scaled base length of 150 nm led to the remarkable reduction in latch-up voltage compared to Si(Ge)-based conventional biristors. The epitaxially grown n-p-n structure allowed an abrupt p-n junction, which was also very important to reduce the latch-up voltage. Furthermore, the physical mechanism of carrier transport in the InGaAs biristor was explored with TCAD simulations.

This paper reports the gain-switched InP-based $\boldsymbol{1.55 \mu\mathrm{m}}$ Qdash lasers on silicon. We investigated the laser performance and related physical parameters by carrying out gain-switching test for lasers on Si and InP. The future direction of improving laser performance was pointed by analyzing the parameters.

The performance of the transistors is a measure for the system to perform desired output. The research in the development of transistors is continuously growing and defines an efficient system and device modeling. This work shows a comparative analysis of the various materials in the double-gate (DG) MOSFET. Here, the DG MOSFETs have been constructed using high-ƙ dielectrics to reduce the short channel effects and improve the performance of the transistors, which is the unit cell of the industrial and consumer electronics devices. This MOSFET can further be optimized by enhancing the analog characteristics in the nanometer regime. This work focuses on the performance of the DG MOSFETs by considering channels like Indium Arsenide (InAs) and Indium Phosphide (InP) in the Aluminium Gallium Arsenide (AlxGa1-xAs) and Gallium Arsenide Antimonide (GaAs1-xSbx) substrates. From the simulation and tabulations, it is evident that the properties of the DG MOSFETs with these novel materials change drastically, thereby inferring the optimum materials in MOSFETs for the high speed and long haul RF applications. In this work, three different models have been proposed, namely Al x Ga 1-x As/HfO 2 , Al x Ga 1-x As/La 2 O 3 , and GaAs 1 - x Sb x /La 2 O 3 ; which shows improvement in threshold voltage with 1.16%, 1.20%, and 1.64% respectively when compared to the conventional Silicon-based DG MOSFETs.

We report a high maximum frequency of oscillation ( ${f} _{\text {max}}$ ) and a current-gain cutoff frequency ( ${f} _{\text {T}}$ ) of 800 and 260 GHz, respectively, with pseudomorphic high-electron mobility transistor (PHEMT), using an InGaAs/InAs composite channel and an asymmetric gate recess. This result was achieved with long gate length ${L} _{\text {G}} = {75}$ nm. The RF small signal equivalent circuit (SSEC) was extracted up to 110 GHz. Moreover, noise parameters extraction gives a minimum noise figure (NFmin) of 0.8 dB (with associated gain ${G} _{\text {ass}} = {16}$ dB) and 1.8 dB (with associated gain ${G} _{\text {ass}} = {11.6}$ dB) at 40 and 94 GHz, respectively. In this study, the gate leakage current was considered in the SSEC of the transistor ( ${g} _{\text {gf}}$ and ${g} _{\text {df}}$ ) and for extraction of the noise parameters.

In this report, a new carbon allotrope named nanoleite is proposed. Its crystal structure is constructed by embedding carbon nanotubes into the matrix of lonsdaleite periodically, leading to a hexagonal primitive unit cell. The equilibrium structure of nanoleite is fully relaxed by density functional theory calculation, and we demonstrate that nanoleite is a semiconductor with an indirect energy bandgap of 2.06 eV. Furthermore, it has a high absorption coefficient in the visible spectrum range, which is comparable to that of the gallium arsenide and indium phosphide. X-ray diffraction patterns and phonon modes are also studied.

We present waveguide photonic crystal reflectors on the InP-membrane-on-silicon (IMOS) platform, and a method to accurately measure the reflectivity of those reflectors. The photonic crystal holes are patterned on a waveguide using electron-beam lithography and etched through the waveguiding layer to create a broadband distributed Bragg reflector. We show simulations of these reflectors and experimental results of fabricated devices, both showing a high, free-to-choose reflectivity, and high quality factor Fabry-Pérot cavities. We experimentally show reflectivities higher than 95% for the reflectors and a quality factor as high as 15,911±511 for a Fabry-Pérot cavity, using reflectors with a length of only 4 microns. For the first time, to our knowledge, two methods for measuring the reflectivity are used for characterization of on-chip reflectors to accurately determine the reflection. The first method is based on analysis of the transmission through a Fabry-Pérot cavity, the second is based on a direct four-port measurement of the reflector. A systematic error is made in both methods, resulting in an upper and lower boundary for the actual reflection coefficient.

Quantum dot (QD) light-emitting diodes (LEDs) are ideal for large-panel displays because of their excellent efficiency, colour purity, reliability and cost-effective fabrication1-4. Intensive efforts have produced red-, green- and blue-emitting QD-LEDs with efficiencies of 20.5 per cent4, 21.0 per cent5 and 19.8 per cent6, respectively, but it is still desirable to improve the operating stability of the devices and to replace their toxic cadmium composition with a more environmentally benign alternative. The performance of indium phosphide (InP)-based materials and devices has remained far behind those of their Cd-containing counterparts. Here we present a synthetic method of preparing a uniform InP core and a highly symmetrical core/shell QD with a quantum yield of approximately 100 per cent. In particular, we add hydrofluoric acid to etch out the oxidative InP core surface during the growth of the initial ZnSe shell and then we enable high-temperature ZnSe growth at 340 degrees Celsius. The engineered shell thickness suppresses energy transfer and Auger recombination in order to maintain high luminescence efficiency, and the initial surface ligand is replaced with a shorter one for better charge injection. The optimized InP/ZnSe/ZnS QD-LEDs showed a theoretical maximum external quantum efficiency of 21.4 per cent, a maximum brightness of 100,000 candelas per square metre and an extremely long lifetime of a million hours at 100 candelas per square metre, representing a performance comparable to that of state-of-the-art Cd-containing QD-LEDs. These as-prepared InP-based QD-LEDs could soon be usable in commercial displays.

GaInAs/InAs composite channels in InP-based pHEMTs enable wideband and/or low-noise performances because of their superior carrier transport properties. To date, the influence of the InAs inset design details on transistor performance has not been parametrized in the literature. We present a systematic study of the effects of the InAs channel inset thickness on transistor characteristics and cutoff frequencies versus temperature, and on the noise performance at 300 K. The epitaxial layer structures considered here incorporate 2 to 5-nm InAs insets in a fixed total composite channel thickness. All layers exhibit excellent electron mobilities (from 40 200 to 54 800 cm2/Vs at 77 K). Thicker InAs insets improve both the current gain cutoff frequency ( ${f}_{\text {T}}$ ) and the maximum oscillation frequency ( ${f}_{\text {MAX}}$ ). However, they also result in higher gate leakage currents and increased channel impact ionization. 50-nm gate length pHEMTs with a 5-nm InAs inset feature the highest simultaneous ${f}_{\text {T}} / {f}_{\text {MAX}} \ge {390}$ /675 (455/800) GHz at 300 (15) K for a low-noise bias but exhibit the poorest minimum noise figure ${NF}_{\text {MIN}}$ . Whereas higher ${f}_{\text {T}}$ (and/or ${f}_{\text {MAX}}$ ) values have traditionally been associated with improved noise performances, this is no longer the case.

Spectral redistribution of the intensity of short- and long-wavelength emission components within gain bandwidth of a 7- to 8-μm quantum-cascade laser under the action of control voltage is demonstrated. As the voltage was increased from 10.5 to 18.2 V, the wavelength of maximum laser emission intensity shifted by approximately 200 nm. The maximum bandwidth of laser gain was about 300 nm (at a temperature of 80 K). The quantum-cascade laser heterostructure was grown by molecular beam epitaxy. The laser active region design was based on double-phonon depopulation of the lower level as implemented on In0.53Ga0.47As/In0.52Al0.48As heteropair of solid alloys lattice-matched with an InP substrate.

In this letter, we have conducted experiments on a traditional uni-traveling carrier photodiode (UTC-PD) and a previously modified UTC-PD under the zero-bias operational condition and make a comparison between them. The experimental results demonstrate that the modified UTC-PD is benefit to high speed, and the 3-dB bandwidth can achieve 40 GHz even when the active diameter of ${14}~{\mu }\text{m}$ under the zero-bias operation. Besides, based on the modified UTC-PD structure, we make some improvements in the collector to restrain the trend in which the bandwidth attenuated by the increase of photocurrent under the zero bias operation.

Here, we report an efficient inverted red indium phosphide (InP) comprising QD (InP/ZnSe/ZnS, core/shell structure) light-emitting diode (QLED) by modulating an interfacial contact between the electron transport layer and emissive InP-QDs and applying self-aging approach. The red InP-QLED with optimized interfacial contact exhibits a significant improvement in maximum external quantum efficiency and current efficiency from 4.42 to 10.2% and 4.70 to 10.8 cd/A, respectively, after 69 days of self-aging, which is an almost 2.3-fold improvement compared to the fresh device. The analysis indicates the consecutive reduction in electron injection and accumulation in the emissive QD due to changes in the conduction band minimum of ZnMgO (0.1 eV after 10 days of storage) through a downward vacuum-level shift according to the aging times. During the device aging periods, the oxygen vacancy of ZnMgO reduces, which leads to lower the conductivity of ZnMgO. As a result, charge balance of the device is improved with the suppression of exciton quenching at the interface of ZnMgO and InP-QD.

We have studied the growth of zinc selenide layers on flat and shaped indium phosphide surfaces. The growth rate of zinc selenide has been shown to depend on substrate orientation. It has been shown that the present results can be useful in designing mesa stripe structures for quantum electronic instruments. We have fabricated mesa stripe laser diodes operating on the absorption band of methane and suitable for producing fiber-optic signal transmission systems.

Due to the inherent toxicity of cadmium selenide (CdSe)-based quantum dots (QDs), Cd-free alternatives are being widely investigated. Indium phosphide (InP) QDs have shown great potential as a replacement for CdSe QDs in display applications. However, the performance of InP-based quantum dot light-emitting diodes (QLEDs) is still far behind that of the CdSe-based devices. In this study, we wanted to show the effects of different approaches to improving the performance of InP-based QLED devices. We investigated the effect of magnesium (Mg) doping in ZnO nanoparticles, which is used as an n-type electron transport layer, in balancing the charge transfer in InP-based QLED devices. We found that an increasing Mg doping level can broaden ZnO band gap, shift its energy levels, but most importantly, increase its resistivity; as a result, the electron current density is significantly reduced and the device efficiency is improved. We also investigated the effect of high-photoluminescence quantum yield emitters and different QLED architectures on the device performance. Through optimizing QD structures and devices, red InP QLEDs with the current efficiencies as high as 11.6 cd/A were fabricated.

We present the results of experiments on the fabrication and study of the properties of quantum-cascade lasers of the spectral range of 7–8 μm in the geometry of a waveguide with a thin top cladding based on indium phosphide. The heterostructure is synthesized by molecular beam epitaxy on an InP substrate with an active region based on a heteropair of In0.53Ga0.47As/Al0.48In0.52As solid alloys. Laser emission at a wavelength of 7.8 μm at a temperature of 300 K with a threshold current density of ~6 kA/cm2 was achieved. The values of characteristic temperatures T0 and T1 for the studied quantum-cascade lasers are of the order of 150 and 450 K, respectively. The results obtained confirm that the design of the waveguide with a thin top cladding for devices for detecting liquids, the fabrication of microfluidic devices, and photonic circuits on silicon holds promise.

We report gallium arsenide (GaAs) growth rates exceeding 300 µm h−1 using dynamic hydride vapor phase epitaxy. We achieved these rates by maximizing the gallium to gallium monochloride conversion efficiency, and by utilizing a mass-transport-limited growth regime with fast kinetics. We also demonstrate gallium indium phosphide growth at rates exceeding 200 µm h−1 using similar growth conditions. We grew GaAs solar cell devices by incorporating the high growth rate of GaAs and evaluated its material quality at these high rates. Solar cell growth rates ranged from 35 to 309 µm h−1 with open circuit voltages ranging from 1.04 to 1.07 V. The best devices exceeded 25% efficiency under the AM1.5 G solar spectrum. The high open-circuit voltages indicate that high material quality can be maintained at these extremely high growth rates. These results have strong implications toward lowering the deposition cost of III-V materials potentially enabling the deposition of high efficiency devices in mere seconds., Gallium arsenide holds record efficiency for single junction solar cells, but high production costs limit applications. Here Metaferia et al. show high quality GaAs and GaInP at rates exceeding 300 and 200 micrometers per hour by dynamic hydride vapor phase epitaxy and > 25% efficient solar cells.

In this letter, a reflection-type arrayed waveguide grating (AWG) (de)multiplexer using high-reflection photonic crystal reflector (PCR) in the Indium-phosphide Membrane on Silicon (IMOS) platform is proposed and experimentally demonstrated for the first time. This reflection-type AWG enables a 35% size-reduced footprint compared with the traditional transmission-type AWG having the same spectral parameters. Considering the realized performance of silicon-nanowire R-AWGs, an acceptable performance ( $680\,\times \,190\,\mu \text {m}^{2}$ size, 6.7-dB loss, and 10-dB crosstalk) is obtained. By using the ultra-small $5.4\,\times \,0.7\,\mu \text {m}^{2}$ PCR, merely 1.1-dB power loss higher than the corresponding transmission-type AWG is implemented. The PCR is a standard building block with a reflectivity of >90%. Besides, the length reduction of the arrayed waveguide will contribute to minimize the accumulated phase error in fabrication.

Molecular beam epitaxy techniques were used to grow a quantum-cascade laser (QCL) heterostructure based on an In0.53Ga0.47As/Al0.48In0.52As heteropair lattice-matched with an InP substrate. InP layers were used to form an optical waveguide. The obtained QCL heterostructure ensured room-temperature lasing in the 8-μm wavelength range at a maximum output optical power of 0.45 W from one facet in a standard ridge geometry of the Fabry–Perot cavities formed by cleaved facets.

Heterophase equilibria in the AlxGayIn1– x– yAszP1 –z/InP heterosystem have been analyzed in terms of a simple solution model in the temperature range 813–1023 K. We have assessed the stability limits of AlGaInAsP solid solutions synthesized on indium phosphide substrates and investigated kinetic features of the crystallization of constant lattice parameter AlGaInAsP solid solutions on InP substrates. The crystallization rate of AlGaInAsP solid solutions on InP substrates has been shown to depend on the synthesis temperature, the molten zone composition and length, and the temperature gradient. In addition, it has been shown to decrease with increasing aluminum concentration, independent of the molten zone length, owing to the decrease in the diffusion coefficient in the liquid phase. We have obtained composition dependences of component distribution coefficients in the AlxGayIn1– x– yAszP1 –z /InP heterosystem and shown that raising the synthesis temperature leads to a reduction in KAl and KP. The effect of synthesis conditions on the structural and luminescence properties of AlGaInAsP solid solutions on InP has been examined.

In this paper, we proposed and designed the high speed uni-traveling carrier photodiodes operating beyond $2~\mu \text{m}$ . InGaAs/GaAsSb type-II multiple quantum wells (MQWs) were used as the absorption region of uni-traveling carrier photodiode to have optical response beyond $2~\mu \text{m}$ . A rate equation model was developed to study the bandwidth characteristics of this photodiode. The carrier dynamics of the carrier sweeping out process was discussed, and the structure parameters of the quantum wells were optimized. Result shows a 3-dB bandwidth over 40 GHz can be achieved with the optimized design. We also studied the feasibility of dual depletion PIN (DD-PIN) photodiode with MQWs absorber. The optimized DD-PIN photodiode could achieve similar bandwidth under relatively high-bias condition.

It is a generally accepted perspective that type-II nanocrystal quantum dots (QDs) have low quantum yield due to the separation of the electron and hole wavefunctions. Recently, high quantum yield levels were reported for cadmium-based typeII QDs. Hence, the quest for finding non-toxic and efficient type-II QDs is continuing. Herein, we demonstrate environmentally benign type-II InP/ZnO/ZnS core/shell/shell QDs that reach a high quantum yield of similar to 91%. For this, ZnO layer was grown on core InP QDs by thermal decomposition, which was followed by a ZnS layer via successive ionic layer adsorption. The small-angle Xray scattering shows that spherical InP core and InP/ZnO core/ shell QDs turn into elliptical particles with the growth of the ZnS shell. To conserve the quantum efficiency of QDs in device architectures, InP/ZnO/ZnS QDs were integrated in the liquid state on blue light-emitting diodes (LEDs) as down-converters that led to an external quantum efficiency of 9.4% and a power conversion efficiency of 6.8%, respectively, which is the most efficient QD-LED using type-II QDs. This study pointed out that cadmium-free type-II QDs can reach high efficiency levels, which can stimulate novel forms of devices and nanomaterials for bioimaging, display, and lighting., European Union;Horizon 2020; European Research Council (ERC); Research and Innovation Programme; Turkish Academy of Sciences (TUBA-GEBIP), Young Scientist Award Program; Science Academy of Turkey (BAGEP), The Young Scientist Award Program; Bilim Kahramanlari Dernegi, Young Scientist Award Program

Promising UTC-PDs have been actively used recently in terms of being an alternative to expensive and bulk THz resources used in many areas such as millimeter and Terahertz (THz) signal (wave) production, communication, imaging and spectroscopy. A new product has been developed by modifying the geometric structure of UTC-PD, which has features such as room temperature usage, high operating speed and high operating frequency. The most important feature of the design is that it performs successfully in 0 (zero) Volt, in other words zerobias, applications and has approximately three times more bandwidth than its equivalent.