Issues concering the replacement of lead in Hi-Rel electronic applications
This paper examines some of these alternative solders for their suitability in replacing tin/lead solder in high-reliability applications.
technologies↗
Engineering topics
Mehta, A.
Publications and source records attributed to Mehta, A..
Laser-welded packaging of a Nd:YAG laser for space applications
This paper describes the fabrication of a rugged, laser-welded package for a 200mW, monolithic diode-pumped solid state Nd:YAG laser operating at 1319nm.
laser↗
Qualifying a cleaning system for space flight printed wiring assemblies
Explore the source record for details and available documents.
cleaning systems printed wiring assemblies (PWA)↗
Qualifying a cleaning system for space flight printed wiring assemblies
This paper addresses a centrifugal cleaning system used in conjunction with a water-based cleaning medium to achieve optimally low levels of contaminants on PWAs.
cleaning systems printed wiring assembly cleanline↗
Dimpled ball grid array process development for space flight applications
A 472 dimpled ball grid array (D-BGA) package has not been used in past space flight environments, therefore it was necessary to develop a process that would yield robust and reliable solder joints. The process developing assembly, inspection and rework techniques, were verified by conducting environmental tests. Since the 472 D-BGA packages passed the above environmental tests within the specifications, the process was successfully developed for space flight electronics.
solder joints↗
Assembly and Cleaning of CSPs for High, Low, and UltraLow Volume Applications
The JPL-led CSP Consortium of enterprises representing government agencies and private companies has joined together to pool in-kind resources for developing the quality and reliability of chip scale packages (CSPs) for a variety of projects.
electronic assembly SMT chip scale package CSP sol↗
Environmental Qualification of Dimpled Ball Grid Arrays for Space Flight Applications
Explore the source record for details and available documents.
Ball Grid Array D-BG4 Qualification↗
Dimpled Ball Grid Array process development for space flight applications
The 472 Dimpled Ball Grid Array (D-BGA) package has not been used in past space flight environments, therefore it is necessary to determine the robustness and reliability of the solder joints. The 472 D-BGA packages passed the above environmental tests within the specifications and are now qualified for use on space flight electronics.
D-BGA Ball Grid Array qualification↗
Continuous Process Involvement
The Electronic Fabrication Section at the Jet Propulsion Laboratories (JPL) has been studying ways to improve Printed Wiring Assembly (PWA) processes. The PWA study described here contained typical surface mount devices including 20 mil fine pitch devices and various BGAs.
surface mount component component lead forming lea↗
Taguchi Experimental Design for Cleaning PWAs with Ball Grid Arrays
Ball grid arrays (BGAs), and other area array packages, are becoming more prominent as a way to increase component pin count while avoiding the manufacturing difficulties inherent in processing quad flat packs (QFPs)...Cleaning printed wiring assemblies (PWAs) with BGA components mounted on the surface is problematic...Currently, a low flash point semi-aqueous material, in conjunction with a batch cleaning unit, is being used to clean PWAs. The approach taken at JPL was to investigate the use of (1) semi-aqueous materials having a high flash point and (2) aqueous cleaning involving a saponifier.
ball grid array area array package semi-aqueous cl↗
Case Studies in Continuous Process Improvement
This study focuses on improving the SMT assembly process in a low-volume, high-reliability environment with emphasis on fine pitch and BGA packages. Before a process improvement is carried out, it is important to evaluate where the process stands in terms of process capability.
SMT BGA process improvement↗