Technical Library | 2013-01-24 20:15:46.0
Being found in the search engines for a wide variety of terms directly related to my business would be my 1st priority...
Technical Library | 2016-11-09 19:22:54.0
Nordson MARCH found a solution for a manufacturer of PCBAs used in ruggedized environments. Read how plasma prior to conformal coating reduced defects and virtually eliminated coating-related failures.
Technical Library | 2011-01-13 17:37:55.0
The tin whisker failures investigated in this paper were found on functional RoHS-compliant hardware. The samples were not conformal coated. This paper will document the conditions associated with the whisker formation under the following conditions; tin
Technical Library | 2022-12-05 16:22:13.0
This paper reviews the possible causes and effects for no-fault-found observations and intermittent fail- ures in electronic products and summarizes them into cause and effect diagrams. Several types of inter- mittent hardware failures of electronic assemblies are investigated, and their characteristics and mechanisms are explored. One solder joint intermittent failure case study is presented. The paper then discusses when no-fault-found observations should be considered as failures. Guidelines for assessment of intermittent failures are then provided in the discussion and conclusions.
Technical Library | 2017-07-06 15:50:17.0
Head-in-pillow (HiP) is a BGA defect which happens when solder balls and paste can't contact well during reflow soldering. Package warpage was one of the major reasons for HiP formation. In this paper, package warpage was measured and simulated. It was found that the package warpage was sensitive to the thickness of inside chips. A FEM method considering viscoelastic property of mold compound was introduced to simulate package warpage. The CTE mismatch was found contributes to more than 90% of the package warpage value when reflowing at the peak temperature. A method was introduced to measure the warpage threshold, which is the smallest warpage value that may lead to HiP. The results in different atmospheres showed that the warpage threshold was 50μm larger in N2 than that in air, suggesting that under N2 atmosphere the process window for HiP defects was larger than that under air, which agreed with the experiments.
Technical Library | 2018-10-29 05:03:59.0
We found that NPI process of SMT is mostly similar and sometimes overlapping to tooling process. In addition, in most cases the programmer is part of the team working on the NPI process. So, QPlan was extended with NPI Tools as a part of tooling process. This allows the team to carry out the NPI process at offline. And at the end of it, they can create corrected SMT program at zero time.
Technical Library | 2009-03-27 22:22:40.0
The Sn-Ag-Cu (SAC) alloys have been considered promising replacements for the lead-containing solders for the microelectronics applications. However, due to the rigidity of the SAC alloys, compared with the Pb-containing alloys, more failures have been found in the drop and high impact applications for the portable electronic devices, such as the personal data assistant (PDA), cellular phone, notebook computer..etc
Technical Library | 2009-10-14 21:17:47.0
Electrochemical migration (ECM) is defined as the growth of conductive metal filaments across a printed circuit board (PCB) in the presence of an electrolytic solution and a DC voltage bias. ECM, also known as dendritic growth, is a critical issue in the electronics industry because the intermittent failure behavior of ECM is a likely root-cause of the high occurrence of field failures identified as no trouble found (NTF)/could not duplicate (CND)
Technical Library | 2016-12-22 16:44:04.0
Particulate matter contamination is known to become wet and therefore ionically conductive and corrosive if the humidity in the environment rises above the deliquescence relative humidity (DRH) of the particulate matter. In wet condition, particulate matter can electrically bridge closely spaced features on printed circuit boards (PCBs), leading to their electrical failure. (...) The objective of this paper is to develop and describe a practical, routine means of measuring the DRH of minute quantities of particulate matter (1 mg or less) found on PCBs.
Technical Library | 2023-06-12 19:46:10.0
Solder paste printing is understood to be the leading contributor of defects in the electronics assembly process. Because yield accounts for such a large percentage of the margin, the greatest opportunity to improve profitability in the assembly of most electronics can be gained by reducing or eliminating solder defects. This article examines process adjustments made through stencil design that correct a misalignment situation between the PCB and stencil, leading to a 43% reduction in assembly defects. Examples of each are found in Table 1.
