Technical Library | 2016-08-24 06:15:35.0
From consumer electronics to systems control, automotive technology to aviation and aerospace – today, electronics are absolutely essential in many sectors. They increasingly replace mechanical components, eliminating wear and tear and thereby extending the service life. What is easily forgotten in this regard is that electronics are also subject to the laws of mechanics. Mechanical test equipment is crucial to test components for the secure hold of welded, soldered or adhesive bonds. A new, mechanically intricate test probe with universal clamping jaws, that can even grasp the individual bonding wires, is in line with the trend toward ever smaller components. Serving as an actuator for these is a micro drive that can be precisely controlled using a miniaturised motion controller to relieve the control unit in the test device.
Technical Library | 2007-01-03 16:36:58.0
Solder paste dispensing is not a new process. However, today's microelectronics present a daunting array of technical challenges to meet deposit size requirements. The need for better paste formulations, more precise equipment, and more tightly controlled processes is driving paste suppliers and equipment suppliers to develop new methods and materials. The most challenging solder paste deposits are those smaller than 0.25mm in diameter and today’s electronics demand such deposits. This paper addresses the process requirements for solder paste micro-deposits in terms of material, equipment and process variable control required for success in producing 0.25mm and smaller deposits.
Technical Library | 2010-06-23 21:59:03.0
Quality control is one of the main bottlenecks in the production of micro-opto-electromechanical systems/microelectromechanical systems (MOEMS/MEMS) because each structure on a wafer is serially inspected and scanned stepwise over the entire wafer area.
Technical Library | 2016-04-28 14:43:23.0
Underfilling is a long-standing process issued from the micro-electronics that can enhance the robustness and the reliability of first or second-level interconnects for a variety of electronic applications. Its usage is currently spreading across the industry fueled by the decreasing reliability margins induced by the miniaturization and interconnect pitch reduction. (...) This paper will address the control of surface mount under filled assemblies, focusing on applicable inspection techniques and possible options to overcome their limitations.
Technical Library | 2008-11-06 02:17:59.0
For many years Acoustic Micro Imaging (AMI) techniques have been utilized to evaluate the quality of the underfill used to support the solder bump interconnections of Flip Chip type devices. AMI has been established as one of the few techniques that can provide reliability and quality control data, but little has been done to automate the evaluation process for Flip Chip underfill until now.
Technical Library | 1999-08-05 09:31:04.0
This document provides suggested standard contents for equipment reference manuals for semiconductor process equipment. It includes a generic and detailed outline for equipment manuals, with major sections on installing, operating, controlling, and integrating process equipment.
Technical Library | 2013-04-25 11:42:01.0
Specification and control of surface roughness of copper conductors within printed circuit boards (PCBs) are increasingly desirable in multi-GHz designs as a part of signal-integrity failure analysis on high-speed PCBs. The development of a quality-assurance method to verify the use of foils with specified roughness grade during the PCB manufacturing process is also important... First published in the 2012 IPC APEX EXPO technical conference proceedings.
Technical Library | 2013-08-07 21:52:15.0
PCB architectures have continued their steep trend toward greater complexities and higher component densities. For quality control managers and test technicians, the consequence is significant. Their ability to electrically test these products is compounded with each new generation. Probe access to high density boards loaded with micro BGAs using a conventional in-circuit (bed-of-nails) test system is greatly reduced. The challenges and complexity of creating a comprehensive functional test program have all but assured that functional test will not fill the widening gap. This explains why sales of automated-optical and automated X-ray inspection (AOI and AXI) equipment have dramatically risen...
Technical Library | 2019-05-01 23:18:27.0
Moisture can accelerate various failure mechanisms in printed circuit board assemblies. Moisture can be initially present in the epoxy glass prepreg, absorbed during the wet processes in printed circuit board manufacturing, or diffuse into the printed circuit board during storage. Moisture can reside in the resin, resin/glass interfaces, and micro-cracks or voids due to defects. Higher reflow temperatures associated with lead-free processing increase the vapor pressure, which can lead to higher amounts of moisture uptake compared to eutectic tin-lead reflow processes. In addition to cohesive or adhesive failures within the printed circuit board that lead to cracking and delamination, moisture can also lead to the creation of low impedance paths due to metal migration, interfacial degradation resulting in conductive filament formation, and changes in dimensional stability. Studies have shown that moisture can also reduce the glass-transition temperature and increase the dielectric constant, leading to a reduction in circuit switching speeds and an increase in propagation delay times. This paper provides an overview of printed circuit board fabrication, followed by a brief discussion of moisture diffusion processes, governing models, and dependent variables. We then present guidelines for printed circuit board handling and storage during various stages of production and fabrication so as to mitigate moisture-induced failures.
| 1 |
winsouce.jpg)
