Technical Library | 2019-05-29 23:10:30.0
There are times when a PCB prototype needs to be built quickly to test out a design. In such cases where it is known early on that there will be multiple iterations or that a "one and done" assembly will be made that there will be some SMT assemblers who choose to hand print solder paste onto the board using a "frameless" stencil. In such cases where hand printing is used, the consistency of the printing technique has typically been in question. Furthermore, the effectiveness of both the nanocoatings as well as the higher end stainless steel materials, which have been heretofore studied in controlled printing environments, will be evaluated for their impact on the hand printing process.The purpose of the study was to determine the effectiveness of select nanocoating materials as well as certain high end stainless steel stencil materials as they relate to the manual SMT printing process. A variety of nanocoatings were applied to SMT metal stencils and solder paste volume measurements were taken to compare the effectiveness.
Technical Library | 1999-05-09 12:36:40.0
The production of electronics began with hand soldering, followed by manual cleaning, which reached its peak during the NASA program. Each step in the process tended to be considered on a stand alone basis, without thought being given to the preceding and following steps. Since each step had its own set of specifications, this led to a "patchwork" approach to overall quality.
Technical Library | 2021-12-03 01:22:50.0
CNC machines is the abbreviation of "Computer Numerical Control" machines. It is an automatic machine tool with program control system. The control system can logically process the programs with control codes or other symbolic instructions, decode them and express them with coded numbers. Next, the coded numbers will be input into the numerical control device through the information carrier. After calculation and processing, the numerical control device sends out various control signals to control the action of the machine tool. CNC machine can automatically produce parts or other products according to the shape and size specified by the drawings.
Technical Library | 2014-08-19 16:04:28.0
SMT assembly planning and failure analysis of surface mount assembly defects often include component warpage evaluation. Coplanarity values of Integrated Circuit packages have traditionally been used to establish pass/fail limits. As surface mount components become smaller, with denser interconnect arrays, and processes such package-on-package assembly become prevalent, advanced methods using dual surface full-field data become critical for effective Assembly Planning, Quality Assurance, and Failure Analysis. A more complete approach than just measuring the coplanarity of the package is needed. Analyzing the gap between two surfaces that are constantly changing during the reflow thermal cycle is required, to effectively address the challenges of modern SMT assembly.
Technical Library | 2010-01-19 19:12:08.0
Learn how Trace, Track and Control (TTC) solutions help manufacturers cut cost, cut waste, automate critical manufacturing processes, and increase yields—all critical elements in today’s economic environment.
Technical Library | 2018-07-03 12:27:02.0
It is becoming increasingly more important to provide a low-cost point-of-care diagnostic device with the ability to detect and monitor various biological and chemical compounds. Traditional laboratories can be time-consuming and very costly. Through the combination of well-established materials and fabrication methods, it is possible to produce devices that meet the needs of many patients, healthcare and medical professionals, and environmental specialists. Existing research has demonstrated that inkjet-printed and paper-based electrochemical sensors are suitable for this application due to advantages provided by the carefully selected materials and fabrication method. Inkjet printing provides a low cost fabrication method with incredible control over the material deposition process, while paper-based substrates enable pump-free microfluidic devices due to their natural wicking ability. Furthermore, electrochemical sensing is incredibly selective and provides accurate and repeatable quantitative results without expensive measurement equipment. By merging each of these favorable techniques and materials and continuing to innovate, the production of low-cost point-of-care sensors is certainly within reach
Technical Library | 2013-10-31 17:36:41.0
Multilayer printed circuit boards (PCBs) that utilize high performance materials are inherently far more challenging for a fabricator to build, due to significant material property differences over standard epoxy glass FR4. These unique material characteristics often require higher processing temperatures, special surface treatments (to aid in hole and surface plating), they possess different expansion properties, making layer-to-layer registration more difficult to control, and require many other unique considerations.
Technical Library | 2012-11-12 14:06:48.0
With consumers constantly looking for lower prices on their technology products and manufacturers trying to squeak out higher margins from their production lines, the need for process control and lower overhead costs have become even more important. One sector that is often overlooked is the hand soldering area of the factory. Many factories have been struggling with antiquated soldering systems for years. In some cases they are trying to make their investment in stations last much longer than they were designed for, or they are falsely trying to recoup their original investment ‐ all at the cost of higher operating expenses or even worse, reduced operator thru‐put.
Technical Library | 2015-06-04 19:10:47.0
Integrators and designers of high-reliability systems exert little or no control over component-level plating processes that affect the propensity for tin whiskering. Challenges of how to assure long-term reliability, while continuing to use COTS parts plated with pure tin, continue to arise. An integrated, quantitative, standardized methodology is proposed whereby mitigation levels can be selected that are appropriate for specific applications of pure tin for given end-uses. A system of hardware end-use classification is proposed, together with recommended appropriate risk mitigation approaches. An updated version of the application-specific risk assessment algorithm is presented together with recommended thresholds for acceptability within the context of the hardware classifications.
Technical Library | 2012-04-05 22:53:10.0
In this paper we show how hybrid control and modeling tech-niques can be put to work for solving a problem of industrial relevance in Surface Mount Technology (SMT) manufacturing. In particular, by closing the loop over the stencil printing process, we ob
