13,006 research outputs found
The Quantum Socket: Three-Dimensional Wiring for Extensible Quantum Computing
Quantum computing architectures are on the verge of scalability, a key
requirement for the implementation of a universal quantum computer. The next
stage in this quest is the realization of quantum error correction codes, which
will mitigate the impact of faulty quantum information on a quantum computer.
Architectures with ten or more quantum bits (qubits) have been realized using
trapped ions and superconducting circuits. While these implementations are
potentially scalable, true scalability will require systems engineering to
combine quantum and classical hardware. One technology demanding imminent
efforts is the realization of a suitable wiring method for the control and
measurement of a large number of qubits. In this work, we introduce an
interconnect solution for solid-state qubits: The quantum socket. The quantum
socket fully exploits the third dimension to connect classical electronics to
qubits with higher density and better performance than two-dimensional methods
based on wire bonding. The quantum socket is based on spring-mounted micro
wires the three-dimensional wires that push directly on a micro-fabricated
chip, making electrical contact. A small wire cross section (~1 mmm), nearly
non-magnetic components, and functionality at low temperatures make the quantum
socket ideal to operate solid-state qubits. The wires have a coaxial geometry
and operate over a frequency range from DC to 8 GHz, with a contact resistance
of ~150 mohm, an impedance mismatch of ~10 ohm, and minimal crosstalk. As a
proof of principle, we fabricated and used a quantum socket to measure
superconducting resonators at a temperature of ~10 mK.Comment: Main: 31 pages, 19 figs., 8 tables, 8 apps.; suppl.: 4 pages, 5 figs.
(HiRes figs. and movies on request). Submitte
Design, processing and testing of LSI arrays hybrid microelectronics task
Those factors affecting the cost of electronic subsystems utilizing LSI microcircuits were determined and the most efficient methods for low cost packaging of LSI devices as a function of density and reliability were developed
Thermal Aging Behavior of Fine Pitch Palladium Coated Silver (PCS) Ball Bonds on Al Metallization
The high price of Au has motivated many to look for alternative bonding wire materials in the field of microelectronics packaging. In the present study, the reliability performance of palladium coated silver (PCS) wire in high temperature storage test (HTST) is carried out using 18 μm diameter fine pitch PCS wire. Fine pitch ball bonds are made on Al metallization, with bonded ball diameter (BBD) of 32 ± 0.5 μm and ball height (BH) of 8 ± 0.5 μm. The aging temperature used in HTST is 170 °C and both shear and pull test are used to evaluate the aged ball bonds at regular time intervals. The shear force increases from 9.9 gf at 96 h to 12.5 gf at 192 h, and remains almost constant until 1344 h, and starts dropping gradually until 10.9 gf at 1848 h. The pad lift percentage recorded in pull test gradually drops from 90 % at 96 h to 20 % at 1008 h, and increases to 90 % at 1848 h. The chip side fractography after shear test indicates that the main failure modes are through pad at 96 h, through ball bond at 504 h, and half of both at 168 h, respectively. Cross-sectional images show that the thickness of the intermetallic compound (IMC) layer growth follows parabolic relationship and the rate constant is 0.10 ± 0.02 μm/h½. Gaps are observed along the periphery of the ball bond interface where no IMC is observed. The IMCs are located at the center of the ball bond interface, and the width is 16.0–19.3 μm at 96 h and 17.2–22.7 μm at 1344 h, respectively
Investigation, Testing, and Selection of Slip-ring Lead Wires for Use in High-precision Slip-ring Capsules Final Report
Evaluation of corrosion resistant silver alloys for use in lead wires for slip-ring assemblies of Saturn guidance and control system
Quantum transport through STM-lifted single PTCDA molecules
Using a scanning tunneling microscope we have measured the quantum
conductance through a PTCDA molecule for different configurations of the
tip-molecule-surface junction. A peculiar conductance resonance arises at the
Fermi level for certain tip to surface distances. We have relaxed the molecular
junction coordinates and calculated transport by means of the Landauer/Keldysh
approach. The zero bias transmission calculated for fixed tip positions in
lateral dimensions but different tip substrate distances show a clear shift and
sharpening of the molecular chemisorption level on increasing the STM-surface
distance, in agreement with experiment.Comment: accepted for publication in Applied Physics
Space station power semiconductor package
A package of high-power switching semiconductors for the space station have been designed and fabricated. The package includes a high-voltage (600 volts) high current (50 amps) NPN Fast Switching Power Transistor and a high-voltage (1200 volts), high-current (50 amps) Fast Recovery Diode. The package features an isolated collector for the transistors and an isolated anode for the diode. Beryllia is used as the isolation material resulting in a thermal resistance for both devices of .2 degrees per watt. Additional features include a hermetical seal for long life -- greater than 10 years in a space environment. Also, the package design resulted in a low electrical energy loss with the reduction of eddy currents, stray inductances, circuit inductance, and capacitance. The required package design and device parameters have been achieved. Test results for the transistor and diode utilizing the space station package is given
ISPET: Interface Sintering Process Enhanced Technology
The research presented in this thesis was carried out in VISHAY Semiconductor Italiana S.P.A. at Borgaro Torinese - Italy.
The framework of this thesis is the study of new materials for power electronics application, analysing their thermal, mechanical and electrical properties. Emerging application of high power systems requires new methods for power electronics integration and packaging. Stringent requirements in size and weight, reliability, durability, ambient and operation temperatures are pushing to go beyond the limits in industrial applications. As a consequence, our studies are focused on power modules, incorporating new materials and technology processes (sintering) for dies or chips (silicon), substrates and interconnection materials (wire bonding).
This thesis work starts introducing the power semiconductor devices used in power electronics and their integration on Power Integrated Circuits (low and medium power density) and Power Modules (medium, high and very high power density). This chapter
will explain technology evolution, power semiconductor device utilization mode and some applications.
Chapter 2 will be focused on power modules packages. They have an important role for providing cooling, electrical connection and correct insulation, between the internal semiconductor devices and the external circuit. Isolated and non isolated packages are
analysed and compared. Chapter 3 will make a point on the methods of thermal characterization and reliability tests, that were implemented to evaluate the impact of the introduction of new materials and processes into the device.
In chapter 4, first experimental results, related to the sintering process will be discussed. In this chapter the attention will be focused on the Chip to substrate Joint of the device, analysing methods to mechanically fix die to substrate. The sintering process will be treated, analysing the process and the results will be thermally and mechanically characterized.
The chapter 5 will present the experimental part oriented to the combinations of materials to produce a better heavy wire bonding, supported by a Design of Experiments (DOE). The behaviour of didifferent wires will be compared through thermal characterization methods and reliability test
Integral Glass Encapsulation for Solar Arrays
Work reported was performed during the period from August 1977 to December 1978. The program objective was to continue the development of electrostatic bonding (ESB) as an encapsulation technique for terrestrial cells. Economic analyses shows that this process can be a cost-effective method of producing reliable, long lifetime solar modules. When considered in sufficient volume, both material and equipment costs are competitive with conventional encapsulation systems. In addition, the possibility of integrating cell fabrication into the encapsulation process, as in the case of the preformed cell contacts discussed in this report, offers the potential of significant overall systems cost reduction
Beam lead technology
Beam lead technology for microcircuit interconnections with applications to metallization, passivation, and bondin
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