Open Access. Powered by Scholars. Published by Universities.®
- Keyword
Articles 1 - 12 of 12
Full-Text Articles in Engineering
Lead-Free Solder Joint Reliability – State Of The Art And Perspectives, Jianbiao Pan, Jyhwen Wang, David M. Shaddock
Lead-Free Solder Joint Reliability – State Of The Art And Perspectives, Jianbiao Pan, Jyhwen Wang, David M. Shaddock
Industrial and Manufacturing Engineering
There is an increasing demand in replacing tin-lead (Sn/Pb) solders with lead-free solders in the electronics industry due to health and environmental concern. The European Union recently passed a law to ban the use of lead in electronic products. The ban will go into effect in July of 2006. The Japanese electronics industry has worked to eliminate lead from consumer electronic products for several years. Although currently there are no specific regulations banning lead in electronics devices in the United States, many companies and consortiums are working on lead-free solder initiatives including Intel, Motorola, Agilent Technologies, General Electric, Boeing, NEMI …
Work In Progress: Combining Concept Inventories With Rapid Feedback To Enhance Learning, John Chen, Jennifer Kadlowec, Dexter Whittinghill
Work In Progress: Combining Concept Inventories With Rapid Feedback To Enhance Learning, John Chen, Jennifer Kadlowec, Dexter Whittinghill
Mechanical Engineering
In this project our goal is to adapt the Concept Inventory for frequent classroom use, and to implement it in a system to provide rapid feedback to students of their understanding of key concepts being presented. The feedback system acts as the focal point and catalyst to encourage students, working in pairs, to assist each other in correcting misconceptions or deepening each other’s understanding of the topic at hand. Furthermore, the system allows the professor to assess the students’ level of comprehension (or misconception) in a just-in-time fashion, and thus guides his or her pacing and coverage of the material. …
Work Flow Policy And Within-Worker And Between-Workers Variability In Performance, Kenneth Howard Doerr, Tali Freed, Terence R. Mitchell, Chester A. Schriesheim, Xiaohua Zhou
Work Flow Policy And Within-Worker And Between-Workers Variability In Performance, Kenneth Howard Doerr, Tali Freed, Terence R. Mitchell, Chester A. Schriesheim, Xiaohua Zhou
Industrial and Manufacturing Engineering
Work flow policies are shown to induce a change in average between-workers variability (worker heterogeneity) and within-worker variability in performance times. In a laboratory experiment, the authors measured the levels of worker heterogeneity and within-worker variability under an individual performance condition, a work sharing condition, and a fixed assignment condition. The work sharing policy increased the levels of worker heterogeneity and worker variability, whereas the fixed assignment policy decreased them. These effects, along with work flow policy main effects on mean performance times and variability are examined. This article represents an initial step in understanding effects that may be important …
Wire Bonding Challenges In Optoelectronics Packaging, Jianbiao Pan, Patrice Fraud
Wire Bonding Challenges In Optoelectronics Packaging, Jianbiao Pan, Patrice Fraud
Industrial and Manufacturing Engineering
Wire bonding has been used in integrated circuit (IC) packaging for many years. However, there are many challenges in wire bonding for optoelectronics packaging. These challenges include bonding on sensitive devices, bonding over cavity, bonding over cantilevel leads and bonding temperature limitations. The optoelectronics package design brings another challenge, which requires wire bonding to have deep access capability. In this paper, the wire bonding technologies are reviewed and ball bonding and wedge bonding are compared. The variables that affect the wire bonding process are then discussed. Finally, the challenges of wire bonding in optoelectronics packaging are presented in detail.
Effect Of Chromium-Gold And Titanium-Titanium Nitride-Platinum-Gold Metallization On Wire/Ribbon Bondability, Jianbiao Pan, Robert M. Pafchek, Frank F. Judd, Jason Baxter
Effect Of Chromium-Gold And Titanium-Titanium Nitride-Platinum-Gold Metallization On Wire/Ribbon Bondability, Jianbiao Pan, Robert M. Pafchek, Frank F. Judd, Jason Baxter
Industrial and Manufacturing Engineering
Gold metallization on wafer substrates for wire/ribbon bond applications require good bond strength to the substrate without weakening the wire/ribbon. This paper compares the ribbon bondability of Cr/Au and Ti/TiN/Pt/Au metallization systems. Both chromium and titanium are used to promote adhesion between substrates and sputtered gold films. Both can diffuse the gold surface after annealing and degrade the wire/ribbon bondability. Restoring bondability by ceric ammonium nitrate (CAN) etch was investigated. Experiments were conducted to investigate the effect of Cr/Au and Ti/TiN/Pt/Au, annealing, and CAN etch processes on 25.4 times; 254 μm (1 × 10 mil) ribbon bonding. All bonds were …
Laser Scanning Thermal Probe: A Novel Approach To Non-Destructive Evaluation, Jacob Kephart, John Chen, Hong Zhang
Laser Scanning Thermal Probe: A Novel Approach To Non-Destructive Evaluation, Jacob Kephart, John Chen, Hong Zhang
Mechanical Engineering
Structuraldefects such as cracks have recently been identifiable through anew nondestructive evaluation (NDE) technique know as sonic IR orthermosonics. However, these defects are depicted through thermal imagining systemas localized "hot spots" indicating a general location of adefect without an accurate portrayal of the dimensions or shapeof the defect. This paper demonstrates a new technique calledLaser Scanning Thermal Probe, LSTP, which utilizes thermography with theuse of heat application in strategic locations to observe spatialheat flow patterns. The LSTP records heat propagation across adefect area previously identified through the thermosonic technique. Thermal gradientswill occur as heat traverses the crack and provide informationto …
Laser Ignition Of Pulverized Coals, John C. Chen, Masayuki Taniguchi, Kiyoshi Narato, Kazuyuki Ito
Laser Ignition Of Pulverized Coals, John C. Chen, Masayuki Taniguchi, Kiyoshi Narato, Kazuyuki Ito
Mechanical Engineering
We present a novel experiment to study the ignition of pulverized coal. A dilute stream of particles is dropped into a laminar, upward-flow wind tunnel with a quartz test section. The gas stream is not preheated. A single pulse from a Nd:YAG laser is focused through the tunnel and ignites the fuel. The transparent test section and cool walls allow for optical detection of the ignition process. In this article we describe the experiment and demonstrate its capabilities by observing the ignition behavior of spherical, amorphous-carbon particles and two coals: an anthracite are a high-volatile bituminous coal. The ignition behaviors …
Critical Variables Of Solder Paste Stencil Printing For Micro-Bga And Fine-Pitch Qfp, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri
Critical Variables Of Solder Paste Stencil Printing For Micro-Bga And Fine-Pitch Qfp, Jianbiao Pan, Gregory L. Tonkay, Robert H. Storer, Ronald M. Sallade, David J. Leandri
Industrial and Manufacturing Engineering
Stencil printing continues to be the dominant method of solder deposition in high-volume surface-mount assembly. Control of the amount of solder paste deposited is critical in the case of fine-pitch and ultrafine-pitch surface-mount assembly. The process is still not well understood as indicated by the fact that industry reports 52-71% surface-mount technology (SMT) defects are related to the solder paste stencil printing process. The purpose of this paper is to identify the critical variables that influence the volume, area, and height of solder paste deposited. An experiment was conducted to investigate the effects of relevant process parameters on the amount …
A Virtual Reality Environment For Multi-Sensor Data Integration, Scott Papson, Joseph Oagaro, Robi Polikar, John Chen, John L. Schmalzel, Shreekanth Mandayam
A Virtual Reality Environment For Multi-Sensor Data Integration, Scott Papson, Joseph Oagaro, Robi Polikar, John Chen, John L. Schmalzel, Shreekanth Mandayam
Mechanical Engineering
Virtual reality (VR) has typically found applications in industrial design, rapid prototyping and advanced scientific visualization. In this paper, we investigate the use of VR for multi-sensor data integration. We attempt to demonstrate that multiple data types-graphical, functional and measurement can be effectively combined inside of a VR environment. This platform allows the user to rapidly sift through large and complex data sets and isolate features of interest. Furthermore, VR environments can be made to evolve based on system data and user input-this provides the ability to develop scenarios that can be used to make informed decisions. Results demonstrating the …
Experimental Investigation Of Statistical Moments Of Travel Time In Grid-Generated Turbulence, Tatiana A. Andreeva, S. B. Meleshi, William W. Durgin
Experimental Investigation Of Statistical Moments Of Travel Time In Grid-Generated Turbulence, Tatiana A. Andreeva, S. B. Meleshi, William W. Durgin
Office of the Provost Scholarship
An experimental technique for investigation of the behavior of acoustic wave propagation through a turbulent medium is discussed. The present study utilizes the ultrasonic travel-time technique to diagnose a grid-generated turbulence. The statistics of the travel-time variations of ultrasonic wave propagation along a path are used to determine some metrics of the turbulence. Experimental data obtained using ultrasonic technique confirms numerical and theoretical predictions of nonlinear increase of the first-order travel time variance with propagation distance.
Digital Imaging Experiences For Undergraduate Engineering Students, Kauser Jahan, John Chen, Shreekanth Mandayam, Robert Krchnavek, Beena Sukumaran, Yusuf Mehta, Jennifer Kadlowec, Paris Von Lockette, Robi Polikar
Digital Imaging Experiences For Undergraduate Engineering Students, Kauser Jahan, John Chen, Shreekanth Mandayam, Robert Krchnavek, Beena Sukumaran, Yusuf Mehta, Jennifer Kadlowec, Paris Von Lockette, Robi Polikar
Mechanical Engineering
Our project is an effort by a multidisciplinary team of engineering faculty members at Rowan University to integrate digital imaging technology (DIT) into the undergraduate engineering curriculum. It builds upon the experience and interest of faculty to promote new topics and innovative methods of teaching. The work is an effort to provide students with the skills directly relevant to the evolving needs of the industry and the marketplace. Projects involve the development of digital imaging curriculum and focus on the creation of a leading edge digital imaging laboratory/studio to facilitate the use of nontraditional learning approaches that encourage interactive learning, …
A Supply Chain Management Tool For Linking Courses In Manufacturing Engineering , Daniel Waldorf, Sema E. Alptekin
A Supply Chain Management Tool For Linking Courses In Manufacturing Engineering , Daniel Waldorf, Sema E. Alptekin
Industrial and Manufacturing Engineering
A Recent Society of Manufacturing Engineers (SME) grant received by Manufacturing Engineering Program at Cal Poly has provided funds to strengthen its curricular focus on supply chain management, flexibility, business skills, quality, and process controls. New courses and laboratories are developed in electronics manufacturing, information technology, and supply chain management. A functioning supply chain environment has been developed to provide vertical integration among several courses. A software tool being developed in-house integrates the activities of the students who play the roles of customers and suppliers. Details of the various components of this comprehensive project are presented in this paper.