Technical Library | 2019-05-30 10:59:13.0
In the current economic environment, the ability to reuse ball grid array(BGA) components that have failed due to solder defects may be an efficient way for electronics manufacturers to reduce costs. Cost may not be the only driving factor in the decision to engage in this recycling practice. The increasing demands placed upon the complexity of microprocessors and integrated circuits (ICs) has decreased the availability of some components, and increased their lead time. Because of this, reballing may provide a means to meet schedule, reduce rework turn-around time, and give a manufacturer a decisive advantage over other companies in an ever increasingly competitive market. This article will discuss the process of reballing BGA components (Figure 1), examining preparation (the preform method, the screen method), and cleaning and bake-out.
Technical Library | 2019-05-31 14:19:24.0
ACI Technologies (ACI) characterized the reliability of surface mount RF components. The RF frequency band of interest was the X band (10.7 to 11.7GHz). A two pronged test for reliability of circuit card assemblies (CCA) was designed for both extreme thermal cycling and vibration. The rapid thermal cycling and extreme vibration testing simulates the total stress encountered by the assembly over the life of the product but accomplishes it in a relatively short period of time. In order to perform the reliability testing, a test vehicle consisting of a printed circuit board with test structures and components, was designed, fabricated, and assembled at ACI.
Technical Library | 2009-04-23 08:14:37.0
No SMT equipment can place accurately and run efficiently without quality nozzles and feeders. These two factors are the core of the pick and place process. If the machine is either unable to pick parts consistently or hold on to the components during the transport from feeder to PCB, defects will result.
Technical Library | 2018-04-27 13:23:31.0
When performing BGA component rework, it is important to know the actual heat that is coming out of the top and bottom heaters. This will be critical in setting up accurate heat profiles. Monitoring your heat output will also keep you aware of your heaters performance so that you will know when the heaters need to be replaced.
Technical Library | 2019-06-03 15:32:40.0
ACI Technologies was pleased to assist a customer by conducting elemental analysis on several assemblies displaying severe corrosion. Several board assemblies had failed in the field and exhibited areas of corrosion in close proximity to onboard components. The most common source of corrosion on electronic assemblies is residual flux. Fluxes are specific chemistries applied during the soldering process which improve the wetting of the solder to both the pad and component when forming the solder joint. They can be highly reactive chemicals that, if left on the assemblies, can lead to corrosion, electrical degradation, and decreased reliability. In the presence of moisture and electrical bias, flux residue can enable dendritic growth as a result of electrochemical migration (ECM).
Technical Library | 2020-08-05 17:13:12.0
A primary issue in electronics reliability for military applications is the ability to ensure long term operability in harsh, extreme environments. This requires more rigid standards, such as the MIL-STD-883 (Department of Defense Test Method Standard for Microcircuits), which commercial grade electronics typically do not satisfy. A solution commonly employed is to package the critical electronic components in hermetically sealed metal or ceramic enclosures which are costly and labor intensive. Not only are the components more expensive, but the assembly process is more difficult to automate, resulting in a substantial cost premium for military grade electronics.
Technical Library | 2019-06-11 09:34:37.0
Recently ACI Technologies was asked to perform failure analysis on a hermetically sealed transistor for potential electrostatic discharge (ESD) or electrostatic overstress (EOS). ACI was asked to determine if the field-failed transistor was damaged by ESD or EOS. In order to properly assess the failure, additional samples were requested.
Technical Library | 2023-09-23 22:31:52.0
Dry boxes can be implemented at various points within the Mfg. environment; for med-long term inventory, or for short term handling on the production floor, and in some cases (with certain conditions) as a process replacement for baking. Bare boards, raw components and partially assembled PCB's can benefit from ultra-low humidity storage.
Technical Library | 1999-08-27 09:29:49.0
Contract packaging houses have to contend with a large mix of die types and products. Flexibility and quick turnaround of package types is a must in this industry. Traditional methods of die encapsulation, (i.e., use of transfer-molding techniques), are only cost effective when producing a large number of components. Liquid encapsulants now provide similar levels of reliability1, and are cost effective...
Technical Library | 2019-05-31 14:21:59.0
Microelectronics is the manufacture of systems built from extremely small electronic components. In today’s electronic world, devices must be portable, equipped with wireless technology and are driven by size, weight, power, and cost (SWaP-C). These system level drivers are crucial to all current and future electronic applications from personal computers and cellular telephones to military-fielded hardware, biomedical instrumentation, and space-flight hardware.
