Microfabrication of Field Emission Devices for Vacuum Integrated Circuits using Orientation Dependent Etching

1986 ◽  
Vol 76 ◽  
Author(s):  
G. J. Campisi ◽  
H. F. Gray

ABSTRACTVacuum integrated circuits and field emission (FE) devices with geometries on the micron and submicron scale have been discussed as alternatives to solid state devices for high speed and hostile environment application as well as for miniature electron sources for CRTs. These miniaturized vacuum devices have been developed on the basis of the advances in micromachining technology, i.e. orientation-dependent etching (ODE) of lithographically patterned silicon. This paper describes the ODE methods used to fabricate pyramidal electron emitter points 1.5 μm high, with radius of curvature of 20 to 100 nm from <100> silicon. In order to reduce operating voltages, an integral extraction electrode (grid) was fabricated by a self-aligned technique. With a single gate mask level the extraction and planar collector structures were fabricated on chip, to form a planar vacuum triode. The final mask step provided the flexibility for fabricating a variety of planar vacuum integrated circuit elements.

Electronics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 964
Author(s):  
Namra Akram ◽  
Mehboob Alam ◽  
Rashida Hussain ◽  
Asghar Ali ◽  
Shah Muhammad ◽  
...  

Modeling and design of on-chip interconnect, the interconnection between the components is becoming the fundamental roadblock in achieving high-speed integrated circuits. The scaling of interconnect in nanometer regime had shifted the paradime from device-dominated to interconnect-dominated design methodology. Driven by the expanding complexity of on-chip interconnects, a passivity preserving model order reduction (MOR) is essential for designing and estimating the performance for reliable operation of the integrated circuit. In this work, we developed a new frequency selective reduce norm spectral zero (RNSZ) projection method, which dynamically selects interpolation points using spectral zeros of the system. The proposed reduce-norm scheme can guarantee stability and passivity, while creating the reduced models, which are fairly accurate across selected narrow range of frequencies. The reduced order results indicate preservation of passivity and greater accuracy than the other model order reduction methods.


Author(s):  
N. David Theodore ◽  
Donald Y.C Lie ◽  
J. H. Song ◽  
Peter Crozier

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.


Author(s):  
Mark Kimball

Abstract This article presents a novel tool designed to allow circuit node measurements in a radio frequency (RF) integrated circuit. The discussion covers RF circuit problems; provides details on the Radio Probe design, which achieves an input impedance of 50Kohms and an overall attenuation factor of 0 dB; and describes signal to noise issues in the output signal, along with their improvement techniques. This cost-effective solution incorporates features that make it well suited to the task of differential measurement of circuit nodes within an RF IC. The Radio Probe concept offers a number of advantages compared to active probes. It is a single frequency measurement tool, so it complements, rather than replaces, active probes.


Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 599
Author(s):  
Jerry R. Meyer ◽  
Chul Soo Kim ◽  
Mijin Kim ◽  
Chadwick L. Canedy ◽  
Charles D. Merritt ◽  
...  

We describe how a midwave infrared photonic integrated circuit (PIC) that combines lasers, detectors, passive waveguides, and other optical elements may be constructed on the native GaSb substrate of an interband cascade laser (ICL) structure. The active and passive building blocks may be used, for example, to fabricate an on-chip chemical detection system with a passive sensing waveguide that evanescently couples to an ambient sample gas. A variety of highly compact architectures are described, some of which incorporate both the sensing waveguide and detector into a laser cavity defined by two high-reflectivity cleaved facets. We also describe an edge-emitting laser configuration that optimizes stability by minimizing parasitic feedback from external optical elements, and which can potentially operate with lower drive power than any mid-IR laser now available. While ICL-based PICs processed on GaSb serve to illustrate the various configurations, many of the proposed concepts apply equally to quantum-cascade-laser (QCL)-based PICs processed on InP, and PICs that integrate III-V lasers and detectors on silicon. With mature processing, it should become possible to mass-produce hundreds of individual PICs on the same chip which, when singulated, will realize chemical sensing by an extremely compact and inexpensive package.


Photonics ◽  
2019 ◽  
Vol 6 (4) ◽  
pp. 103 ◽  
Author(s):  
Alison Perrott ◽  
Ludovic Caro ◽  
Mohamad Dernaika ◽  
Frank Peters

The mutual and injection locking characteristics of two integrated lasers are compared, both on and off-chip. In this study, two integrated single facet slotted Fabry–Pérot lasers are utilised to develop the measurement technique used to examine the different operational regimes arising from optically locking a semiconductor diode laser. The technique employed used an optical spectrum analyser (OSA), an electrical spectrum analyser (ESA) and a high speed oscilloscope (HSO). The wavelengths of the lasers are measured on the OSA and the selected optical mode for locking is identified. The region of injection locking and various other regions of dynamical behaviour between the lasers are observed on the ESA. The time trace information of the system is obtained from the HSO and performing the FFT (Fast Fourier Transform) of the time traces returns the power spectra. Using these tools, the similarities and differences between off-chip injection locking with an isolator, and on-chip mutual locking are examined.


1985 ◽  
Vol 63 (6) ◽  
pp. 683-692 ◽  
Author(s):  
H. D. Barber

Silicon bipolar device technologies provided 65% of the world's integrated circuits in 1983. Where low noise, high current, low or high voltage, high speed or low cost are required, bipolar technologies are used. This paper will review the present status of bipolar device technologies, which make possible 100-ps gate-propagation delays, 150-μm2 gate areas, 1-GHz bandwidth amplifiers, on-chip control of over 1-A, 350-V operation, 14-GHz fT's and 10-ns. analogue-to-8-bit digital conversion. These devices are realized because of advances in isolation techniques, chemical-vapor deposition, photolithography, diffusion, ion implantation, conductor–contact interconnection technology, etching processes, and materials preparation. This paper will discuss some of the fundamental problems, modelling difficulties, and technological barriers that will impact the future development of bipolar integrated circuits.


2015 ◽  
Vol 1 (8) ◽  
pp. e1500257 ◽  
Author(s):  
Chuang Zhang ◽  
Chang-Ling Zou ◽  
Yan Zhao ◽  
Chun-Hua Dong ◽  
Cong Wei ◽  
...  

A photonic integrated circuit (PIC) is the optical analogy of an electronic loop in which photons are signal carriers with high transport speed and parallel processing capability. Besides the most frequently demonstrated silicon-based circuits, PICs require a variety of materials for light generation, processing, modulation, and detection. With their diversity and flexibility, organic molecular materials provide an alternative platform for photonics; however, the versatile fabrication of organic integrated circuits with the desired photonic performance remains a big challenge. The rapid development of flexible electronics has shown that a solution printing technique has considerable potential for the large-scale fabrication and integration of microsized/nanosized devices. We propose the idea of soft photonics and demonstrate the function-directed fabrication of high-quality organic photonic devices and circuits. We prepared size-tunable and reproducible polymer microring resonators on a wafer-scale transparent and flexible chip using a solution printing technique. The printed optical resonator showed a quality (Q) factor higher than 4 × 105, which is comparable to that of silicon-based resonators. The high material compatibility of this printed photonic chip enabled us to realize low-threshold microlasers by doping organic functional molecules into a typical photonic device. On an identical chip, this construction strategy allowed us to design a complex assembly of one-dimensional waveguide and resonator components for light signal filtering and optical storage toward the large-scale on-chip integration of microscopic photonic units. Thus, we have developed a scheme for soft photonic integration that may motivate further studies on organic photonic materials and devices.


2004 ◽  
Vol 13 (04) ◽  
pp. 789-811
Author(s):  
EDUARD ALARCÓN ◽  
GERARD VILLAR ◽  
ALBERTO POVEDA

Two case examples of high-speed CMOS microelectronic implementations of high-performance controllers for switching power converters are presented. The design and implementation of a current-programmed controller and a general-purpose feedforward one-cycle controller are described. The integrated circuit controllers attain high-performance by means of using current-mode analog signal processing, hence allowing high switching frequencies that extend the operation margin compared to previous designs. Global layout-extracted transistor-level simulation results for 0.8 μm and 0.35 μm standard CMOS technologies confirm both the correct operation of the circuits in terms of bandwidth as well as their functionality for the control of switching power converters. The circuits may be used either as standalone IC controllers or as controller circuits that are technology-compatible with on-chip switching power converters and on-chip loads for future powered systems-on-chip.


2019 ◽  
Vol 2019 (1) ◽  
pp. 000243-000247
Author(s):  
Robert B. Paul ◽  
A. Ege Engin ◽  
Jerry Aguirre

Abstract To develop reliable high-speed packages, characterization of the underfill material used in the flip-chip process has become of greater importance. The underfill, typically an epoxy resin-based material, offers thermal and structural benefits for the integrated circuit (IC) on package. With so many inputs and outputs (IOs) in close proximity to one another, the integrated circuits on package can have unexpected signal and power integrity issues. Furthermore, chip packages can support signals only up to the frequency where noise coupling (e.g., crosstalk, switching noise, etc.) leads to the malfunctioning of the system. Vertical interconnects, such as vias and solder bumps, are major sources of noise coupling. Inserting ground references between every signal net is not practical. For the solder bumps, the noise coupling depends on the permittivity of the underfill material. Therefore, characterizing the permittivity of the underfill material helps in predicting signal and power integrity issues. Such liquid or semi-viscous materials are commonly characterized from a simple fringe capacitance model of an open-ended coaxial probe immersed in the material. The open-ended coaxial method, however, is not as accurate as resonator-based methods. There is a need for a methodology to accurately extract the permittivity of liquid or semi-viscous materials at high frequencies. The proposed method uses solid walled cavity resonators, where the resonator is filled with the underfill material and cured. Dielectric characterization is a complex process, where the physical characteristics of the cavities must be known or accurately measured. This includes the conductivity of the conductors, roughness of the conductors, the dimensions of the cavity, and the port pin locations. This paper discusses some of the challenges that are encountered when characterizing dielectrics with cavity resonators. This characterization methodology can also be used to characterize other materials of interest.


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