16×16 optical-fiber crossbar switch operating at 0.85 μm

An optical-fiber crossbar switch has been constructed using fully integrated GaAs optoelectronic receivers, custom monolithic GaAs laser drivers, and an electrical 32×32 silicon crossbar switch. 470 Mb/s operation has been achieved with a bit error rate of less than 10^-12. The approach uses a monolithic GaAs optoelectronic integrated receiver to convert optical signals into electrical signals that are fed into an Si 32×32 electronic crossbar switch. The switch outputs are used to drive laser transmitters consisting of a custom monolithic GaAs IC laser driver and a 0.85 μm GaAs/AlGaAs laser. The system could be reconfigured in 1 μm, limited by the control logic, with the switch chip capable of reconfiguration in 35 ns. No errors are induced by reconfiguration     

Self‐Organization of a Highly Integrated Silicon Nanowire Network on a Si(110)–16 × 2 Surface by Controlling Domain Growth

Here, bottom‐up nanofabrication for the two‐dimensional self‐organization of a highly integrated, well‐defined silicon nanowire (SiNW) mesh on a naturally‐patterned Si(110)–16 × 2 surface by controlling the lateral growths of two non‐orthogonal 16 × 2 domains is reported. This self‐ordered nanomesh consists of two crossed arrays of parallel‐aligned SiNWs with nearly identical widths of 1.8–2.5 nm and pitches of 5.0–5.9 nm, and is formed over a mesoscopic area of 300 × 270 nm² so as to show a high integration density in excess of 10⁴ µm^?2. These crossed SiNWs exhibit semiconducting character with an equal band gap of ～0.95 eV as well as unique quantum confinement effect. Such an ultrahigh‐density SiNW network can serve as a versatile nanotemplate for nanofabrication and nanointegration of the highly‐integrated metal‐silicide or molecular crossbar nanomesh on Si(110) surface for a broad range of device applications. Also, the multi‐layer, vertically‐stacked SiNW networks can be self‐assembled through hierarchical growth, which opens the possibility for creating three‐dimensionally interconnected crossbar circuits. The ability to self‐organize an ultrahigh‐density, functional SiNW network on a Si(110) surface represents a simple step toward the fabrication of highly‐integrated crossbar nanocircuits in a very straightforward, fast, cost‐effective, and high throughput process.     

Thermal calculation of SiC <Emphasis Type="Italic">p-i-n</Emphasis> diodes

Thermal calculations of various design models of SiC p-i-n diodes with a structure capacity of 0.2 pF are carried out for substrate thicknesses of 360, 50, and 2 mm. Comparison with a silicon p-i-n structure on an integrated heat sink is performed.     

A GaAs up converter integrated circuit for a double conversioncable TV “set-top” tuner

A GaAs up converter integrated circuit used for a double conversion cable TV “set-top” tuner is described. The up converter IC converts the 50 to 550 MHz band to an IF of 700 MHz. The IC meets the linearity and noise figure requirements for a cable TV tuner. It includes an AGC and image reject filter. The reduced component count achieved by using an integrated circuit and the resulting reduction in the size of the tuner, provides potential cost savings over a discrete implementation     

High‐Performance On‐Chip Thermionic Electron Micro‐Emitter Arrays Based on Super‐Aligned Carbon Nanotube Films

An important advancement towards the realization of miniaturized and fully integrated vacuum electronic devices will be the development of on‐chip integrated electron sources with stable and reproducible performances. Here, the fabrication of high‐performance on‐chip thermionic electron micro‐emitter arrays is demonstrated by exploiting suspended super‐aligned carbon nanotube films as thermionic filaments. For single micro‐emitter, an electron emission current up to ≈20 µA and density as high as ≈1.33 A cm^?2 are obtained at a low‐driven voltage of 3.9 V. The turn‐on/off time of a single micro‐emitter is measured to be less than 1 µs. Particularly, stable (±1.2% emission current fluctuation for 30 min) and reproducible (±0.2% driven voltage variation over 27 cycles) electron emission have been experimentally observed under a low vacuum of ≈5 × 10^?4 Pa. Even under a rough vacuum of ≈10^?1 Pa, an impressive reproducibility (±2% driven voltage variation over 20 cycles) is obtained. Moreover, emission performances of micro‐emitter arrays are found to exhibit good uniformity. The outstanding stability, reproducibility, and uniformity of the thermionic electron micro‐emitter arrays imply their promising applications as on‐chip integrated electron sources.     

40 GHz Vertical Transition with a Dual‐Mode Cavity for a Low‐Temperature Co‐fired Ceramic Transceiver Module

A new vertical transition between a substrate integrated waveguide in a low‐temperature co‐fired ceramic substrate and an air‐filled standard waveguide is proposed in this paper. A rectangular cavity resonator with closely spaced metallic vias is designed to connect the substrate integrated waveguide to the standard air‐filled waveguide. Physical characteristics of an air‐filled WR‐22 to WR‐22 transition are compared with those of the proposed transition. Simulation and experiment demonstrate that the proposed transition shows a ?1.3 dB insertion loss and 6.2 GHz bandwidth with a 10 dB return loss for the back‐to‐back module. A 40 GHz low‐temperature co‐fired ceramic module with the proposed vertical transition is also implemented. The implemented module is very compact, measuring 57 mm × 28 mm × 3.3 mm.     

A new damascene architecture for high-performance metal–insulator–metal capacitors integration

As high-performance metal–insulator–metal capacitors are required for new technologies, an innovative architecture was developed with standard damascene processes used for copper interconnect realization. Low-cost damascene capacitors were integrated with thin Si₃N₄ films, leading to 2.9 fF/μm² capacitance values and low leakage currents, demonstrating this architecture ability to reduce the insulators thickness, thus achieving high-performance passive implementation for mixed integrated circuits.     

Foldable All‐Solid‐State Supercapacitors Integrated with Photodetectors

Recent development in flexible electronics has promoted the increasing demand for their energy storage systems that will be lightweight, thin, flexible, and even foldable. Although various flexible supercapacitors recently have been successfully developed, the design and assembly of highly foldable supercapacitors have received less attention. Furthermore, foldable supercapacitors are in general operated independently with other electronics, resulting in some space and energy consumption from the external connection system. Therefore, the authors fabricate the foldable all‐solid‐state integrated devices with supercapacitor and photodetector functions in a simplified and compact configuration based on single‐walled carbon nanotube films and TiO₂ nanoparticles. The integrated devices not only retain the intrinsic capacitance behavior but also show excellent sensitivity of detecting white light. More importantly, the capacitance behavior of integrated devices remains almost unchanged and the photodetector behavior is quite stable even folded by 180° due to their unique integrated configuration. Such rational design of all‐solid‐state integrated devices will pave the way for assembling energy storage devices and other electronics into highly flexible and foldable integrated devices.     

Rear‐Illuminated Perovskite Photorechargeable Lithium Battery

Photovoltaic power‐conversion systems can harvest energy from sunlight almost perpetually whenever sunrays are accessible. Meanwhile, as indispensable energy storage units used in advanced technologies such as portable electronics, electric vehicles, and renewable/smart grids, batteries are energy‐limited closed systems and require constant recharging. Fusing these two essential technologies into a single device would create a sustainable power source. Here, it is demonstrated that such an integrated device can be realized by fusing a rear‐illuminated single‐junction perovskite solar cell with Li₄Ti₅O₁₂‐LiCoO₂ Li‐ion batteries, whose photocharging is enabled by an electronic converter via voltage matching. This design facilitates a straightforward monolithic stacking of the battery on the solar cell using a common metal substrate, which provides a robust mechanical isolation between the two systems while simultaneously providing an efficient electrical interconnection. This system delivers a high overall photoelectric conversion‐storage efficiency of 7.3%, outperforming previous efforts on stackable integrated architectures with organic–inorganic photovoltaics. Furthermore, converter electronics facilitates system control with battery management and maximum power point tracking, which are inevitable for efficient, safe, and reliable operation of practical loads. This work presents a significant advancement toward integrated photorechargeable energy storage systems as next‐generation power sources.     

A Compact Integrated Polarization Splitter/Converter in InGaAsP–InP

A novel design for an integrated passive polarization splitter/converter combination is presented. The device consists of a Mach-Zehnder interferometer with polarization converters in both arms. The device is analyzed using the transfer matrix method and fabricated in InGaAsP-InP. Measurement results show a splitting ratio of approximately 10 dB and a conversion of >90%. This device can be monolithically integrated with passive and active components.     

Monolithic integration of a metal—semiconductor—metal photodiode and a GaAs preamplifier

A metal-semiconductor-metal (MSM) photodiode and a preamplifier have been monolithically integrated on a GaAs substrate by a very simple fabrication process. Measurements have shown that the constituent MSM photodiode has a sensitivity of 2.2 A/W and a -3-dB cutoff frequency of as high as 1 GHz. The present photodiode has been found to realize an extremely high photosensitivity of the monolithically integrated circuit, 26 mV/µW.     

Resonant‐Enhanced Full‐Color Emission of Quantum‐Dot‐Based Display Technology Using a Pulsed Spray Method

Colloidal quantum‐dot light‐emitting diodes (QDLEDs) with the HfO₂/SiO₂‐distributed Bragg reflector (DBR) structure are fabricated using a pulsed spray coating method. Pixelated RGB arrays, 2‐in. wafer‐scale white light emission, and an integrated small footprint white light device are demonstrated. The experimental results show that the intensity of red, green, and blue (RGB) emission exhibited considerable enhancement because of the high reflectivity in the UV region by the DBR structure, which subsequently increases the use in the UV optical pumping of RGB QDs. A pulsed spray coating method is crucial in providing uniform RGB layers, and the polydimethylsiloxane (PDMS) film is used as the interface layer between each RGB color to avoid cross‐contamination and self‐assembly of QDs. Furthermore, the chromaticity coordinates of QDLEDs with the DBR structure remain constant under various pumping powers in the large area sample, whereas a larger shift toward high color temperatures is observed in the integrated device. The resulting color gamut of the proposed QDLEDs covers an area 1.2 times larger than that of the NTSC standard, which is favorable for the next generation of high‐quality display technology.     

Ultrahigh‐Working‐Frequency Embedded Supercapacitors with 1T Phase MoSe2 Nanosheets for System‐in‐Package Application

Commercial aluminium electrolyte capacitors (AECs) are too large for integration in future highly integrated electronic systems. Supercapacitors, in comparison, possess a much higher capacitance per unit volume and can be embedded as passive capacitors to address such challenges in electronics scaling. However, the slow frequency response (<10¹ Hz) typical of supercapacitors is a major hurdle to their practical application. Here, it is demonstrated that 1T‐phase MoSe₂ nanosheets obtained by laser‐induced phase transformation can be used as an electrode material in embedded micro‐supercapacitors. The metallic nature of MoSe₂ nanosheet‐based electrodes provides excellent electron‐ and ion‐transport properties, which leads to an unprecedented high‐frequency response (up to 10⁴ Hz) and cycle stability (up to 10⁶ cycles) when integrated in supercapacitors, and their power density can be ten times higher than that of commercial AECs. Furthermore, fabrication processes of the present device are fully compatible with system‐in‐package device manufacturing to meet stringent specifications for the size of embedded components. The present research represents a critical step forward in in‐package and on‐chip applications of electrolytic capacitors.     

Ultra‐small Form‐Factor Helix on Pad‐Type Stage‐Bypass WCDMA Tx Power Amplifier Using a Chip‐Stacking Technique and a Multilayer Substrate

A fully integrated small form‐factor HBT power amplifier (PA) was developed for UMTS Tx applications. For practical use, the PA was implemented with a well configured bottom dimension, and a CMOS control IC was added to enable/disable the HBT PA. By using helix‐on‐pad integrated passive device output matching, a chip‐stacking technique in the assembly of the CMOS IC, and embedding of the bulky inductive lines in a multilayer substrate, the module size was greatly reduced to 2 mm × 2.2 mm. A stage‐bypass technique was used to enhance the efficiency of the PA. The PA showed a low idle current of about 20 mA and a PAE of about15% at an output power of 16 dBm, while showing good linearity over the entire operating power range.     

High-symmetry DC SQUID based on the Nb/AlO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>/Nb Josephson junctions for nondestructive evaluation

Topology of high-symmetry thin-film SQUIDs based on the Nb/AlO _x /Nb tunneling junctions is developed and optimized. The devices exhibit relatively low sensitivity to static external field and electric interference. An experimentally implemented SQUID sensor with an integrated input coil with a sensitivity of 0.26 μA/Ф₀ exhibits an intrinsic noise with respect to magnetic flux of less than \(5\mu {\Phi _0}/\sqrt {Hz} \). A system for encapsulation of sensors is developed for applications in multichannel systems for nondestructive evaluation of materials and alternative diagnostic systems.     

A highly integrated wideband millimeter-wave MMIC converter using0.25-μm P-HEMT technology

A highly integrated wideband converter that was designed to upconvert the entire 6- to 18-GHz input RF frequency band to a 22-GHz intermediate frequency using a 28- to 40-GHz local oscillator (LO) is described. The circuit was designed using 0.25-μm pseudomorphic HEMT technology. The converter incorporates a three-stage RF amplifier, a three-stage LO amplifier, and an active balanced mixer, all integrated on a chip 96 mil×96 mil in size. The upconverter monolithic microwave integrated circuit (MMIC) has an average of 10-dB conversion gain across the full 6-18-GHz input band     

A Temperature‐Controllable Microelectrode and Its Application to Protein Immobilization

This letter presents a smart integrated microfluidic device which can be applied to actively immobilize proteins on demand. The active component in the device is a temperature‐controllable microelectrode array with a smart polymer film, poly(N‐isopropylacrylamide) (PNIPAAm) which can be thermally switched between hydrophilic and hydrophobic states. It is integrated into a micro hot diaphragm having an integrated micro heater and temperature sensors on a 2‐micrometer‐thick silicon oxide/silicon nitride/silicon oxide (O/N/O) template. Only 36 mW is required to heat the large template area of 2 mm×16 mm to 40°C within 1 second. To relay the stimulus‐response activity to the microelectrode surface, the interface is modified with a smart polymer. For a model biomolecular affinity test, an anti‐6‐(2, 4‐dinitrophenyl) aminohexanoic acid (DNP) antibody protein immobilization on the microelectrodes is demonstrated by fluorescence patterns.     

Genesis of “Solitary Cations” Induced by Atomic Hydrogen

Substitution of constituent atoms and/or changes of crystal structure are routinely used to tailor the fundamental properties of a semiconductor. Here, it is shown that such a tailoring can also be realized thanks to a novel hydrogen effect. Four hydrogen atoms can screen the effect the crystal potential has on a constituent cation, thus generating a solitary cation: an effectively isolated impurity, so chemically different from the unscreened constituent cations that it strongly perturbs the electronic properties of the material by increasing its fundamental band‐gap energy. Such a hydrogen‐induced screening effect is removed by thermal treatments, thus permitting reversible modifications of both the “crystal chemistry” and material's properties. This phenomenon, observed in InN and other topical nitrides, should permit the development of a new class of materials as well as the fabrication of photonic devices and optical integrated circuits with distinct, tailor‐made regions emitting or absorbing light, all integrated onto a monolithic semiconductor structure.     

Graphene‐Based Actuator with Integrated‐Sensing Function

Flexible actuators have important applications in artificial muscles, robotics, optical devices, and so on. However, most of the conventional actuators have only actuation function, lacking in real‐time sensing signal feedbacks. Here, to break the limitation and add functionality in conventional actuators, a graphene‐based actuator with integrated‐sensing function is reported, which avoids the dependence on image post‐processing for actuation detection and realizes real‐time measurement of the shape‐deformation amplitudes of the actuator. The actuator is able to show a large bending actuation (curvature of 1.1 cm^?1) based on a dual‐mode actuation mechanism when it is driven by near infrared light. Meanwhile, the relative resistance change of the actuator is ?17.5%. The sensing function is attributed to piezoresistivity and thermoresistivity of the reduced graphene oxide and paper composite. This actuator can be used as a strain sensor to monitor human motions. A smart gripper based on the actuators demonstrates perfect integration of the actuating and sensing functions, which can not only grasp and release an object, but also sense every actuation state of the actuator. The developed integrated‐sensing actuator is hopeful to open new application fields in soft robotics, artificial muscles, flexible wearable devices, and other integrated‐multifunctional devices.     

Fully Integrated HBT MMIC Series‐Type Extended Doherty Amplifier for W‐CDMA Handset Applications

A highly efficient linear and compactly integrated series‐type Doherty power amplifier (PA) has been developed for wideband code‐division multiple access handset applications. To overcome the size limit of a typical Doherty amplifier, all circuit elements, such as matching circuits and impedance transformers, are fully integrated into a single monolithic microwave integrated circuit (MMIC). The implemented PA shows a very low idle current of 25 mA and an excellent power‐added efficiency of 25.1% at an output power of 19 dBm by using an extended Doherty concept. Accordingly, its average current consumption was reduced by 51% and 41% in urban and suburban environments, respectively, when compared with a class‐AB PA. By adding a simple predistorter to the PA, the PA showed an adjacent channel leakage ratio better than —42 dBc over the whole output power range.