Silicon Technology Research Articles

A Fully Integrated 490-GHz CMOS Heterodyne Imager Adopting Second Subharmonic Resistive Mixer Structure

A fully integrated 490-GHz heterodyne imager is reported. The imager adopts a second subharmonic resistive mixer wherein the transmission lines and small capacitors are used to enhance port-to-port isolation and the suppression of undesired local oscillator (LO) leakage and harmonic mixing components. The imager achieves a minimum noise equivalent power of 1.2 pW/Hz0.5 while dissipating 26 mW from a 1.2-V supply. This work presents the highest frequency implementation among the reported fully integrated heterodyne imagers in silicon technology.

Contribution of Solar Photovoltaic on the Reduction of Greenhouse Gas Emission in the Indonesia Power Sector

Indonesia has released the target of reducing Greenhouse gas (GHG) emissions. The strategy includes enhancement renewable energy utilization. One of the most potential renewable energy resources in Indonesia is solar energy. State Electricity Company of Indonesia has planned to develop solar Photo voltaic (PV) power plan in the document planning 2019-2028. The objective of this study is to explore the contribution of solar PV to the reduction GHG of Indonesia. The potency of solar irradiance and solar PV output in several big cities in Indonesia are discussed. The results show that by using the PV technology of Crystalline silicon with mounting position building integrated and the slope and azimuth is 0°, the average solar PV output in Indonesia is 1361.2 kWh/kWp. The planned solar PV installed capacity by the end of 2028 is 985.5 MW. The electricity resulted by the system in a year will be 1341.47 GWh or it is only 0.31% of national electricity consumption. The contribution of solar PV to the GHG emission reduction is 1.341 million tons CO2eq in the year 2028.

Current progress in electrode/pentacene interfaces of pentacene-based organic thin films transistors: A review

Organic thin-film transistors (OTFTs) in device physics is currently considered as a standout amongst the most progressive concepts of device applications. Currently, due to humongous technological progress, OTFT with high mobilities can be produced that are comparable to silicon technology. This remarkable mobility is considered as a benchmark for more demanding applications which is accomplished by novel, tenable organic semiconductor materials such as pentacene and the tailoring of their geometries and characteristics. In addition, pentacene demonstrates charge carrier mobilities up to 5.5 cm2/Vs. However very low mobility was achieved in OTFTs due to fabrication defects, material processing etc. The most important defect that arise during the fabrication process is contact interfaces in OTFTs, which highly effect the device performance. Thus, in this article, we will review the current progress of contact engineering of OTFTs with special emphasis on electrode/pentacene interfaces of pentacene-based organic thin film transistors. Further, this review aims to provide an in-depth understanding of bottlenecks to improve the OTFTs performance. After a short introduction, the historical background of pentacene-based OTFTs is discussed that focuses on different methods and materials employed so far to improve the contact between pentacene layer. Also, the review presents the key challenges in the geometry of pentacene based OTFT that is the direct deposition of metal electrodes onto the pentacene channel layer in top contact interface due to which poor carrier injection, high barrier height, chemical diffusion between both layers, high contact resistance and surface roughness has been observed which highly affects the device performance especially the field effect mobility. Also, the state-of-the-art devices and related models that widely employ pentacene are presented. This detailed review will assist the future researchers in understanding and improving field-effect properties of OTFTs.

LOGIC THRESHOLD FOR MICRORING RESONATOR-BASED BDD CIRCUITS: PHYSICAL AND OPERATIONAL ANALYSES

Moore’s Law has been the fuel of expansive innovation in computing. The chip industry kept the Moore’s law extant for almost four decades. However, the halt of the rapid progress of the silicon technology is incipient by reason of the physical limitations. Emerging computing proposals suggest several alternatives to current computing paradigms and technologybases. The photonic circuitry is one of the most promising candidates with its high operation speed, energy efficient passive components, low crosstalk and appropriateness for parallel computation. Among various approaches to photonic logic, microring resonator-based Binary-Decision Diagram (BDD) architectures have a special place due to their small circuit footprint. However, the physical limitations imposed on their logic implementation has not been studied in depth to enable design of efficient circuits. In this paper, we study the physical structure and operational details of a microring resonatorbased Half-Adder (HA) circuit and outline the conditions under which the performance and accuracy of information processing is compromised due to its physical characteristics. Our analyses significantly contribute to determining key physical features and operations concerning logic implementation of microring resonator based BDD HA, which informs the future design and operational optimization of the microring resonator-based BDD logic circuits.

Experimental characterization of directional couplers in InP photonic membranes on silicon (IMOS)

We experimentally study the performance of directional couplers fabricated in indium-phosphide membrane on silicon (IMOS) technology. We both investigate the validity of the coupled mode theory (CMT) applied to directional coupler structures with high index contrast and study the effect of some different topological choices in device fabrication. In particular, besides the conventional curved structures, we consider ultra sharp corner bends that reduce the footprint. The effect of fabrication tolerances on the different guided mode polarizations is also discussed.

Graphene and two-dimensional materials for silicon technology.

The development of silicon semiconductor technology has produced breakthroughs in electronics-from the microprocessor in the late 1960s to early 1970s, to automation, computers and smartphones-by downscaling the physical size of devices and wires to the nanometre regime. Now, graphene and related two-dimensional (2D) materials offer prospects of unprecedented advances in device performance at the atomic limit, and a synergistic combination of 2D materials with silicon chips promises a heterogeneous platform to deliver massively enhanced potential based on silicon technology. Integration is achieved via three-dimensional monolithic construction of multifunctional high-rise 2Dsilicon chips, enabling enhanced performance by exploiting the vertical direction and the functional diversification of the silicon platform for applications in opto-electronics and sensing. Here we review the opportunities, progress and challenges of integrating atomically thin materials with silicon-based nanosystems, and also consider the prospects for computational and non-computational applications.

Event-driven implementation of deep spiking convolutional neural networks for supervised classification using the SpiNNaker neuromorphic platform

Neural networks have enabled great advances in recent times due mainly to improved parallel computing capabilities in accordance to Moore’s Law, which allowed reducing the time needed for the parameter learning of complex, multi-layered neural architectures. However, with silicon technology reaching its physical limits, new types of computing paradigms are needed to increase the power efficiency of learning algorithms, especially for dealing with deep spatio-temporal knowledge on embedded applications. With the goal of mimicking the brain’s power efficiency, new hardware architectures such as the SpiNNaker board have been built. Furthermore, recent works have shown that networks using spiking neurons as learning units can match classical neural networks in supervised tasks. In this paper, we show that the implementation of state-of-the-art models on both the MNIST and the event-based NMNIST digit recognition datasets is possible on neuromorphic hardware. We use two approaches, by directly converting a classical neural network to its spiking version and by training a spiking network from scratch. For both cases, software simulations and implementations into a SpiNNaker 103 machine were performed. Numerical results approaching the state of the art on digit recognition are presented, and a new method to decrease the spike rate needed for the task is proposed, which allows a significant reduction of the spikes (up to 34 times for a fully connected architecture) while preserving the accuracy of the system. With this method, we provide new insights on the capabilities offered by networks of spiking neurons to efficiently encode spatio-temporal information.

3D Nanoprinting of Perovskites.

As competing with the established silicon technology, organic-inorganic metal halide perovskites are continually gaining ground in optoelectronics due to their excellent material properties and low-cost production. The ability to have control over their shape, as well as composition and crystallinity, is indispensable for practical materialization. Many sophisticated nanofabrication methods have been devised to shape perovskites; however, they are still limited to in-plane, low-aspect-ratio, and simple forms. This is in stark contrast with the demands of modern optoelectronics with freeform circuitry and high integration density. Here, a nanoprecision 3D printing is developed for organic-inorganic metal halide perovskites. The method is based on guiding evaporation-induced perovskite crystallization in mid-air using a femtoliter ink meniscus formed on a nanopipette, resulting in freestanding 3D perovskite nanostructures with a preferred crystal orientation. Stretching the ink meniscus with a pulling process enables on-demand control of the nanostructure's diameter and hollowness, leading to an unprecedented tubular-solid transition. With varying the pulling direction, a layer-by-layer stacking of perovskite nanostructures is successfully demonstrated with programmed shapes and positions, a primary step for additive manufacturing. It is expected that the method has the potential to create freeform perovskite nanostructures for customized optoelectronics.

Nanosystems, Edge Computing, and the Next Generation Computing Systems.

It is widely recognized that nanoscience and nanotechnology and their subfields, such as nanophotonics, nanoelectronics, and nanomechanics, have had a tremendous impact on recent advances in sensing, imaging, and communication, with notable developments, including novel transistors and processor architectures. For example, in addition to being supremely fast, optical and photonic components and devices are capable of operating across multiple orders of magnitude length, power, and spectral scales, encompassing the range from macroscopic device sizes and kW energies to atomic domains and single-photon energies. The extreme versatility of the associated electromagnetic phenomena and applications, both classical and quantum, are therefore highly appealing to the rapidly evolving computing and communication realms, where innovations in both hardware and software are necessary to meet the growing speed and memory requirements. Development of all-optical components, photonic chips, interconnects, and processors will bring the speed of light, photon coherence properties, field confinement and enhancement, information-carrying capacity, and the broad spectrum of light into the high-performance computing, the internet of things, and industries related to cloud, fog, and recently edge computing. Conversely, owing to their extraordinary properties, 0D, 1D, and 2D materials are being explored as a physical basis for the next generation of logic components and processors. Carbon nanotubes, for example, have been recently used to create a new processor beyond proof of principle. These developments, in conjunction with neuromorphic and quantum computing, are envisioned to maintain the growth of computing power beyond the projected plateau for silicon technology. We survey the qualitative figures of merit of technologies of current interest for the next generation computing with an emphasis on edge computing.

Deformed octagon-hexagon-square structure of group-IV and group-V elements and III-V compounds

We report the prediction of a two-dimensional (2D) allotrope common to group-IV and group-V elements and III-V compounds, which consist of two nonplanar atomic layers connected by vertical bonds and form deformed octagon, hexagon, and squares (dohs) with threefold and fourfold coordinated atoms. Specifically for silicon, it is a semiconductor with cohesion stronger than silicene and can be chemically doped to have localized donor and acceptor states in the band gap. This allotrope can be functionalized to construct quasi-2D clathrates with transition metal atoms and attain spin polarized metallic, half-metallic, or semiconducting states. It is demonstrated that these properties can be maintained, when it is grown on a specific substrate. Stringent tests show that the atomic structure is dynamically stable and can sustain thermal excitation at high temperatures. Additionally, stable bilayer, as well as 3D layeredlike structures, can be constructed by the vertical stacking of single-layer dohs. Surprisingly, C, Ge, AlP, and GaAs can form also similar 2D semiconducting structures. In contrast to semiconducting black and blue phosphorene, P-dohs is a semimetal with band inversion. While the premise of using well-developed silicon technology in 2D electronics has been hampered by the semimetallic silicene, the realization of this 2D, semiconducting allotrope of silicon and compounds can constitute a productive direction in 2D nanoelectronics/spintronics.

Laser-Processed Nanosilicon: A Multifunctional Nanomaterial for Energy and Healthcare.

This review describes promising laser-based approaches to produce silicon nanostructures, including laser ablation of solid Si targets in residual gases and liquids and laser pyrolysis of silane. These methods are different from, and complementary to, widely used porous silicon technology and alternative synthesis routes. One can use these methods to make stable colloidal dispersions of silicon nanoparticles in both organic and aqueous media, which are suitable for a multitude of applications across the important fields of energy and healthcare. Size tailoring allows production of Si quantum dots with efficient photoluminescence that can be tuned across a broad spectral range from the visible to near-IR by varying particle size and surface functionalization. These nanoparticles can also be integrated with other nanomaterials to make multifunctional composites incorporating magnetic and/or plasmonic components. In the energy domain, this review highlights applications to photovoltaics and photodetectors, nanostructured silicon anodes for lithium ion batteries, and hydrogen generation from water. Application to nanobiophotonics and nanomedicine profits from the excellent biocompatibility and biodegradability of nanosilicon. These applications encompass several types of bioimaging and various therapies, including photodynamic therapy, RF thermal therapy, and radiotherapy. The review concludes with a discussion of challenges and opportunities in the applications of laser-processed nanosilicon.

(Invited) 3D Passive Devices and Through-Substrate Connections for Medical and Automotive Applications

Murata has developed a unique technology in silicon for capacitors and interposers with integrated passive devices .The research was focused on advanced concepts with 3D trenches with extremely high aspect ratio and exquisite high K dielectrics to get to the highest capacitor density with excessive reliability. The technology is compliant with strong capability in terms of packaging enabling outstanding performances of miniaturized products and heterogeneous solutions. This paper outlines two stacking technologies: one in medical where the performance and form factor parameter are becoming more and more important and the other one is in automotive where higher computing performance will be entailed. Both are subject to demanding requirements in terms of reliability. The 3D integration schemes, one that doesn’t rely on traditional methods of interconnect and the other with Through Silicon Via (TSV), will be depicted in addition to the manufacturing processes.

Application of Atomic Layer Deposition of Cellulosic Materials Prepared Using 3D Printing Concepts

Atomic layer deposition offers a 3-diemensional conformal deposition of materials along with the atomic scale control on thickness control at the low-temperature regimes. Metal oxide materials can be exploited to the nanoscale coating onto the underlying materials. The cellulose materials offer ecofriendly applications which can be designed to the versatile fabric products or equivalents. The integration of ALD onto the cellulose materials can be tailored towards stretchable electronics which allows the flexible deformation unlike the previous rigid applications based glass or silicon technologies. Zinc oxide (ZnO) is chosen to be a coating material characteristic of semiconducting conduction. The zinc oxide thin films are deposited through the atomic layer deposition of diethyl zinc (DEZ) water. The ALD-based zinc oxide thin films are characterized by a multitude of physical/chemical probing tools: X-ray photoelectron microscopy for bonding and composition information, X-ray diffraction for crystallinity, atomic force microscopy and scanning electron microscopy for morphological characterization, and dc/ac-based electrical characterizations. Cellulose and its derivatives are ecofriendly materials due to superior features tensile strength and toughness contrary to the pollution-inducing thermoplastic materials. The beneficial features are applied to building materials, pharmaceuticals, cosmetics, and foods. The cellulose-based materials are chemically versatile and artificially controlled. The current work exploits two specific features, i.e. i) the dissolution feature of cellulose acetate in acetone and the OH terminated features of cellulose materials. The flexible cellulose materials are prepared using a 3-dimensional printing concept: the cellulose acetate materials are dissolved intro acetone and the subsequent removal of acetone allows the flexible solid formation of cellulose materials after extrusion through high-resolution 3D-printing. The mesh-typed specimens are subjected to simultaneous measurements on mechanical deformation and electrical resistance. The electrical/dielectric monitoring is performed in the two-point electrode configuration involving ac and dc characterizations. In particular, the frequency-dependent impedance spectroscopy provides a wealth of information on bulk- and/or electrode-responses as a function of mechanical deformation. The applicability of ALD to cellulose materials is discussed in terms of mechanical robustness and electrical reliability required in high-performance stretchable electronics.

Millimeter-Wave Noise Source Development on SiGe BiCMOS 55-nm Technology for Applications up to 260 GHz

This paper describes the development and characterization of a millimeter-wave (mmW) integrated noise source development on silicon technology for applications up to 260 GHz. The developed integrated noise source is based on p-n and Schottky junction in series, realized on the SiGe BiCMOS 55-nm technology from STMicroelectronics. Biased in the avalanche regime, this integrated diode noise source achieves a tunable excess noise ratio (ENR) ranged between 0 dB and 15 dB, in the 130–260-GHz frequency range. In order to highlight the usefulness of the integrated noise source, the noise figure of two amplifiers was measured: the first one is an integrated low-noise amplifier (LNA) operating in the D-band (130–170 GHz) while the second one is packaged and operates from 220 to 260 GHz. Due to its ability to be naturally integrated on silicon, this noise source features a strong interest to carry out high-frequency in situ noise characterization of advanced Si CMOS or BiCMOS technologies in the mmW range.

An Improved Room-Temperature Silicon Terahertz Photodetector on Sapphire Substrates**Supported by the National Natural Science Foundation of China under Grant Nos 61775060 and 61275100.

We design and fabricate a good performance silicon photoconductive terahertz detector on sapphire substrates at room temperature. The best voltage responsivity of the detector is 6679V/W at frequency 300 GHz as well as low voltage noise of 3.8 nV/Hz1/2 for noise equivalent power 0.57 pW/Hz1/2. The measured response time of the device is about , demonstrating that the detector has a speed of . The achieved good performance, together with large detector size (acceptance area is 3 ), simple structure, easy manufacturing method, compatibility with mature silicon technology, and suitability for large-scale fabrication of imaging arrays provide a promising approach to the development of sensitive terahertz room-temperature detectors.

Quantum Nature of Light in Nonstoichiometric Bulk Perovskites.

Sources of single photons are a fundamental brick in the development of quantum information technologies. Great efforts have been made so far in the realization of reliable, highly efficient, and on demand quantum sources that could show an easy integration with quantum devices. This has recently culminated in the use of solid state quantum dots as promising candidates for future sources of quantum technologies. However, some challenges, like their complex fabrication, random distribution, and difficult integrability with silicon technology, could hinder their broad application, making necessary the study of alternative systems. In this work, we clearly demonstrate single photon emission from quantum dots formed in nonstoichiometric bulk perovskites. Their simple growing procedures, exceptional stability under constant illumination, easy control of their optical properties, as well as ease of integrability make these materials very interesting candidates for the development of quantum light sources in the near-infrared.

Mechanically Stacked, Two-Terminal Graphene-Based Perovskite/Silicon Tandem Solar Cell with a Stabilized Efficiency of 25.9%

Perovskite/silicon tandem solar cells represent an attractive strategy to push the market-leading crystalline silicon technology beyond its theoretical limit, maintaining low module costs. Record-high efficiency silicon heterojunction cells with a micrometre-sized pyramid textured front-surface hinder high-temperature and low-cost solution processing of the top-cell in a monolithic architecture. We present a mechanically stacked two-terminal perovskite/silicon tandem device, allowing independent fabrication and optimization of the sub-cells, subsequently coupled by contacting the back-electrode of the mesoscopic perovskite top-cell with the texturized and metalized front-contact of the silicon bottom-cell. Our champion device exhibits a stabilized efficiency of 25.9% over a 1.43 cm2 active area, achieved by optically engineering the hole-selective layer/rear-contact structure to minimize the optical losses, and improving the electrical performance with a graphene-doped mesoporous electron-selective layer. This represents a simple path toward fabricating tandem devices overcoming the limit of single junction solar cells and with a competitive levelized cost of energy.

A Practical Study of the Effect of Vacuum Hole Design of Rubbertip in the Manufacturability of Thin Silicon Technology

A Practical Study of the Effect of Vacuum Hole Design of Rubbertip in the Manufacturability of Thin Silicon Technology

Silicon Technology Inspired Test Structures and Methodology for SFQ Model-to-Hardware Correlation

A test structure suite to measure circuit delays, power, and operating margins of single flux quantum (SFQ) circuits and to derive key parameters directly from dc testable high-speed circuits is described. This suite comprises a set of ring oscillators and a time-differential experiment as well as isolated circuit components. Measured data are compared to the results obtained from circuit simulations conducted in a design environment used for more complex chip designs. This approach, which enables tracking of process technology and validation of device and circuit models in a self-consistent manner, is inspired by a similar methodology for silicon technology deployed successfully by IBM and its alliance partners.

Гранулирование пылевых отходов кремниевого производства для возврата в технологический процесс

The purpose of the work is to propose a granulation technology for dust waste of metallurgical silicon production for its recycling in the process of ore-thermal reduction of silica. The technology includes the stages of magnetic separation, granulation and drying. Experimental works on iron oxide separation from cyclone dust were performed using a magnetic analyzer of the AMR type (Ukraine). Granulation was carried out using a drum granulator R-020 (Russia). The chemical composition was analyzed with the help of an optical emission spectrometer Varian 730-ES (USA). It has been determined that up to 37% of iron oxide is separated by the method of magnetic separation of silicon production cyclone dust. In the laboratory pelletization in a drum granulator the granules of 10-70 mm in size with the porosity of 40-45% were obtained. The carried out experiments have showed that there is a possibility in principle to use production wastes in the production technology of silicon of metallurgical grades as a pelletized additive to the main (lump) charge. Based on the results obtained, a line for granulating dust waste was proposed.