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Electrical compensation system for plated-through-hole tester. Milestone report

Description: A microprocessor system has been developed to control the acquisition and interpretation of resistance-measurement data from plated-through holes in printed wiring boards. The system provides a direct digital display of the thickness of the copper plating on the hole walls. The complex calibration for holes having different geometries is stored in the memory of the system, and the geometry factors are input through thumbwheel switches. A special probe system makes possible the determination of … more
Date: October 1, 1978
Creator: Abel, W.B.
Partner: UNT Libraries Government Documents Department
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Microhm resistance measurements to determine plating thickness on PWB

Description: The Bendix Corporation, Kansas City Division has been involved in an effort to improve and extend the usee of micro-resistance testing for the evaluation of copper plating quality and thickness on printed circuit boards. This activity has concentrated on three applications: measurement of the copper plating thickness on the surface of panel plated boards; conductor thickness of pattern plated boards; and the evaluation of plated through holes. The nature of this activity, the equipment used in … more
Date: unknown
Creator: Abel, W.B.
Partner: UNT Libraries Government Documents Department
open access

Plated-through hole testing. Final repot

Description: An improved microresistance testing method to measure the thickness of copper plating in plated-through holes of double-sided printed wiring boards is presented. A new probe design, combined with a microprocessor controller, makes it possible for a direct reading tester to provide variables data. Tester design and software programs for the system are included. Results of correlation studies, comparing the improved resistance method to cross-sectional measurements are presented. Limitations on t… more
Date: May 1, 1980
Creator: Abel, W.B.
Partner: UNT Libraries Government Documents Department
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Evaluation of the SC-1/megasonic clean for sub-0.15 micron particle removal

Description: A statistical design of experiments approach has been employed to evaluate the particle removal efficacy of the SC-1/megasonic clean for sub-0.15 {mu}m inorganic particles. The effects of megasonic input power, solution chemistry, bath temperature, and immersion time have been investigated. Immersion time was not observed to be a statistically significant factor. The NH{sub 4}OH/H{sub 2}O{sub 2} ratio was significant, but varying the molar H{sub 2}O{sub 2} concentration had no effect on inorgan… more
Date: July 1, 1994
Creator: Adkins, C. L. J.; Resnick, P. J.; Clews, P. J.; Thomas, E. V.; Korbe, N. C. & Cannaday, S. T.
Partner: UNT Libraries Government Documents Department
open access

Modeling micro-electronics drill bit behavior with ABAQUS Standard

Description: Modeling of drill bit behavior under applied forces as well as modeling of the drilling process itself can aid in the understanding of the relative importance of the various drill bit process parameters and can eventually lead to improved drill bit designs. In this paper the authors illustrate the application of ABAQUS Standard to the stress and deformation analysis of micro-electronics drill bits that are used in manufacturing printed circuit boards. Effects of varying point geometry, web tape… more
Date: June 1, 1997
Creator: Anderson, C. A. & Ricketson, E.
Partner: UNT Libraries Government Documents Department
open access

Document Template for Printed Circuit Board Layout

Description: The purpose of this document is to list the information that may be required to properly specify a printed circuit board (PCB) design. You must provide sufficient information to the PCB layout vendor such that they can quote accurately and design the PCB that you need. Use the following information as a guide to write your specification. Include as much of it as is necessary to get the PCB design that you want.
Date: January 1, 1998
Creator: Anderson, J. T.
Partner: UNT Libraries Government Documents Department
open access

Architecture of a Silicon Strip Beam Position Monitor

Description: A collaboration between Fermilab and the Institute for High Energy Physics (IHEP), Beijing, has developed a beam position monitor for the IHEP test beam facility. This telescope is based on 5 stations of silicon strip detectors having a pitch of 60 microns. The total active area of each layer of the detector is about 12 x 10 cm{sup 2}. Readout of the strips is provided through the use of VA1 ASICs mounted on custom hybrid printed circuit boards and interfaced to Adapter Cards via copper-over-ka… more
Date: October 1, 2010
Creator: Angstadt, R.; Cooper, W.; Demarteau, M.; Green, J.; Jakubowski, S.; Prosser, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Solderability perservative coatings: Electroless tin vs. organic azoles

Description: This paper compares the solderability performance and corrosions ion protection effectiveness of electroless tin coatings versus organic azole films after exposure to a series of humidity and thermal (lead-free solders) cycling conditions. The solderability of immersion tin is directly related to the tin oxide growth on the surface and is not affected by the formation of Sn-Cu intermetallic phases as long as the intermetallic phase is protected by a Sn layer. For a nominal tin thickness of 60{m… more
Date: July 1, 1993
Creator: Artaki, I.; Ray, U.; Jackson, A. M.; Gordon, H. M. & Vianco, P. T.
Partner: UNT Libraries Government Documents Department
open access

An Evaluation of Prototype Circuit Boards Assembled with a Sn-Ag Bi Solder

Description: An evaluation was performed which examined the aging of surface mount solder joints assembled with 91.84Sn-3.33Ag-4.83Bi solder. Defect analysis of the as-fabricated test vehicles revealed excellent solderability, good package alignment, and a minimum number of voids. Continuous DC electrical monitoring of the solder joints did not reveal opens during as many as 10,000 thermal cycles (0 C, 100 C). The solder joints exhibited no significant degradation through 2500 cycles, based upon an absence … more
Date: September 1, 1999
Creator: Artaki, I.; Ray, U.; Rejent, Jerome A. & Vianco, Paul T.
Partner: UNT Libraries Government Documents Department
open access

Laser drilling of printed wiring boards: Final report on work sponsored by Sandia LDRD program

Description: Traditionally, electrical connections- between layers of a printed wiring board are formed by mechanically drilling holes through all layers and then plating the resulting structure to provide electrical connections between the layers. The mechanical drilling process is very capital- and labor-intensive and is often a bottleneck in board production. The goal of this program was the development of laser drilling as an alternative to mechanical drilling. Cost advantages and the ability to produce… more
Date: May 1, 1994
Creator: Arzigian, J. S.
Partner: UNT Libraries Government Documents Department
open access

A TEM-horn antenna with dielectric lens for fast impulse response

Description: We designed and constructed a pair of TEM-horn antennas specifically for the very fast time-domain boresight response. Two physical topologies were made. A printed-board configuration has much slower transient response, which we think is due to pulse-smearing of the antenna currents in the dielectric substrate of the printed wiring boards. The solid state version has a 20 ps transition duration response in the main beam endfire (boresight) direction, which is the fastest we have seen to date. A… more
Date: December 31, 1995
Creator: Aurand, J. F.
Partner: UNT Libraries Government Documents Department
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Electro-Microfluidic Packaging

Description: Electro-microfluidics is experiencing explosive growth in new product developments. There are many commercial applications for electro-microfluidic devices such as chemical sensors, biological sensors, and drop ejectors for both printing and chemical analysis. The number of silicon surface micromachined electro-microfluidic products is likely to increase. Manufacturing efficiency and integration of microfluidics with electronics will become important. Surface micromachined microfluidic devices … more
Date: June 1, 2002
Creator: BENAVIDES, GILBERT L. & GALAMBOS, PAUL C.
Partner: UNT Libraries Government Documents Department
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Preliminary characterization of active MEMS valves.

Description: Partial characterization of a series of electrostatically actuated active microfluidic valves is to be performed. Tests are performed on a series of 24 valves from two different MEMS sets. Focus is on the physical deformation of the structures under variable pressure loadings, as well as voltage levels. Other issues that inhibit proper performance of the valves are observed, addressed and documented as well. Many microfluidic applications have need for the distribution of gases at finely specif… more
Date: August 1, 2010
Creator: Barnard, Casey Anderson
Partner: UNT Libraries Government Documents Department
open access

Environmental evaluation of Surface Mounted Devices (SMD)

Description: We evaluated the comparative reliability of solder interconnections used for Leadless Chip Carriers (LCCs), Meaded, and flat-pack hybrid microcircuits mounted on FR-4 glass epoxy printed wiring boards (PWBs). The board assemblies, with solder attached microcircuits, were repeatedly thermal cycled from - 65 to +125{degrees}C. We recognize that this temperature range far exceeds most testing of assemblies. The purposes of these tests were to evaluate worst-case conditions and to obtain comparativ… more
Date: June 1, 1997
Creator: Barr, V.C. & Andrade, A.D.
Partner: UNT Libraries Government Documents Department
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Assessing the operational life of flexible printed boards intended for continuous flexing applications : a case study.

Description: Through the vehicle of a case study, this paper describes in detail how the guidance found in the suite of IPC (Association Connecting Electronics Industries) publications can be applied to develop a high level of design assurance that flexible printed boards intended for continuous flexing applications will satisfy specified lifetime requirements.
Date: January 1, 2011
Creator: Beck, David Franklin
Partner: UNT Libraries Government Documents Department
open access

Interconnection technology

Description: A project was conducted to develop interconnection techniques for application to present and future electronic assemblies--especially those using hybrid microcircuits (HMCs). Project work included: (1) determination of the relative costs of welding opposed to the soldering of HMC packages; (2) evaluation of the solderability of thin films including definition of solderability tests; (3) establishment of a thermocompression (TC) bonding schedule to attach gold plated copper leads to thin film go… more
Date: August 1, 1976
Creator: Beck, W. P. & Sim, J. R.
Partner: UNT Libraries Government Documents Department
open access

Organic solderability preservation evaluation. Topical report

Description: An evaluation was conducted to determine the possible replacement of the hot air solder leveling (HASL) process used in the Allied Signal Federal Manufacturing & Technologies (FM&T) Printed Wiring Board Facility with an organic solderability preservative (OSP). The drivers for replacing HASL include (1) Eliminating lead from PWB fabrication processes; (2) Potential legislation restricting use of lead, (3) Less expensive processing utilizing OSP rather than HASL processing; (4) Avoiding solder d… more
Date: March 1, 1997
Creator: Becka, G.A.; McHenry, M.R. & Slanina, J.T.
Partner: UNT Libraries Government Documents Department
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SmartShelf{trademark}: Report of activities for fiscal year 1997

Description: This report covers activities relating to the SmartShelf{trademark} project during the period October 1, 1996, through September 30, 1997. During this year, project team members have advanced the state of both the hardware and software through a six-month-long test that exercised all hardware and nearly all software components. Second-generation node hardware was constructed and tested with the system and it was found that components supplied by Dallas Semiconductor did not meet the manufacture… more
Date: September 26, 1997
Creator: Bell, Z.W. & Lawson, R.L.
Partner: UNT Libraries Government Documents Department
open access

Ionic contamination detection. Final report

Description: The effectiveness of Meter A and B for detecting ionic contamination was evaluated and compared on the following types of samples: (1) copper panels, (2) printed wiring boards with through-hold components (lCs), (3) printed wiring boards with surface-mounted components, and (4) mixed-technology printed wiring boards (both through-hole and surface-mount components). The extraction efficiency of the two meters was calculated
Date: April 1, 1994
Creator: Benkovich, M. G.
Partner: UNT Libraries Government Documents Department
open access

Development of a semi-automated workcell for repair of printed circuit boards

Description: Printed circuit boards that comprise US Army electronic systems are repaired at Army depots. An existing automated diagnostic system determines the area of failure; either by identifying failed components or failed board traces. Currently, repairs are performed manually by trained technicians. A system is being developed for repair of through-hole printed circuit boards. It is comprised of many automated and operator-assisted functions to perform the multiple operations related to replacement o… more
Date: August 1, 1990
Creator: Bennett, David W. & Evans, Mark S.
Partner: UNT Libraries Government Documents Department
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Materials preparation and fabrication of pyroelectric polymer/silicon MOSFET detector arrays. Final report

Description: The authors have delivered several 64-element linear arrays of pyroelectric elements fully integrated on silicon wafers with MOS readout devices. They have delivered detailed drawings of the linear arrays to LANL. They have processed a series of two inch wafers per submitted design. Each two inch wafer contains two 64 element arrays. After spin-coating copolymer onto the arrays, vacuum depositing the top electrodes, and polarizing the copolymer films so as to make them pyroelectrically active, … more
Date: March 27, 1992
Creator: Bloomfield, P.
Partner: UNT Libraries Government Documents Department
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Fabrication of a 275/sup 0/C geothermal temperature tool

Description: The fabrication of a Prototype 275/sup 0/C Geothermal Temperature Tool is reviewed. This tool fabrication uses hybrid circuits that were developed at Sandia National Laboratories and are now being built at Teledyne Philbrick. To achieve high-temperature operation, the standard military specification hybrid technology was modified in fabrication processes and materials.
Date: January 1, 1981
Creator: Bonn, P.A.
Partner: UNT Libraries Government Documents Department
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