Technical Library | 2020-08-27 01:22:45.0
Initially adopted internal specifications for acceptance of printed circuit boards (PCBs) used for wire bonding was that there were no nodules or scratches allowed on the wirebond pads when inspected under 20X magnification. The nodules and scratches were not defined by measurable dimensions and were considered to be unacceptable if there was any sign of a visual blemish on wire-bondable features. Analysis of the yield at a PCB manufacturer monitored monthly for over two years indicated that the target yield could not be achieved, and the main reasons for yield loss were due to nodules and scratches on the wirebonding pads. The PCB manufacturer attempted to eliminate nodules and scratches. First, a light-scrubbing step was added after electroless copper plating to remove any co-deposited fine particles that acted as a seed for nodules at the time of copper plating. Then, the electrolytic copper plating tank was emptied, fully cleaned, and filtered to eliminate the possibility of co-deposited particles in the electroplating process. Both actions greatly reduced the density of the nodules but did not fully eliminate them. Even though there was only one nodule on any wire-bonding pad, the board was still considered a reject. To reduce scratches on wirebonding pads, the PCB manufacturer utilized foam trays after routing the boards so that they did not make direct contact with other boards. This action significantly reduced the scratches on wire-bonding pads, even though some isolated scratches still appeared from time to time, which caused the boards to be rejected. Even with these significant improvements, the target yield remained unachievable. Another approach was then taken to consider if wire bonding could be successfully performed over nodules and scratches and if there was a dimensional threshold where wire bonding could be successful. A gold ball bonding process called either stand-off-stitch bonding (SSB) or ball-stitch-on-ball bonding (BSOB) was used to determine the effects of nodules and scratches on wire bonds. The dimension of nodules, including height, and the size of scratches, including width, were measured before wire bonding. Wire bonding was then performed directly on various sizes of nodules and scratches on the bonding pad, and the evaluation of wire bonds was conducted using wire pull tests before and after reliability testing. Based on the results of the wire-bonding evaluation, the internal specification for nodules and scratches for wirebondable PCBs was modified to allow nodules and scratches with a certain height and a width limitation compared to initially adopted internal specifications of no nodules and no scratches. Such an approach resulted in improved yield at the PCB manufacturer.
New Equipment | Test Equipment
PTS 310 Frequency Synthesizer Items were pulled from a working Lab Environment, no further testing has been done. Features 0.1 MHz to 310 MHz new standard in performance/price, with choice of spurious suppression DDS standard wi
New Equipment | Test Equipment
PTS D310 Dual Channel Frequency Synthesizer Items were pulled from a working Lab Environment, no further testing has been done. Features two fully independent channels, each covering 0.1-310 MHz +3 to +13 dBm output low pha
New Equipment | Test Equipment
Items were pulled from a working Lab Environment, no further testing has been done. Associated Research 403AI A.C. Junior Hypot. http://www.ebay.com/itm/Associated-Research-403AI-A-C-Junior-Hypot-/161077717342?pt=LH_DefaultDomain_0&hash=item2
Technical Library | 2020-08-05 18:49:32.0
The evolution of internet-enabled mobile devices has driven innovation in the manufacturing and design of technology capable of high-frequency electronic signal transfer. Among the primary factors affecting the integrity of high-frequency signals is the surface finish applied on PCB copper pads – a need commonly met through the electroless nickel immersion gold process, ENIG. However, there are well-documented limitations of ENIG due to the presence of nickel, the properties of which result in an overall reduced performance in high-frequency data transfer rate for ENIG-applied electronics, compared to bare copper. An innovation over traditional ENIG is a nickel-less approach involving a special nano-engineered barrier designed to coat copper contacts, finished with an outermost gold layer. In this paper, assemblies involving this nickel-less novel surface finish have been subjected to extended thermal exposure, then intermetallics analyses, contact/sheet resistance comparison after every reflow cycle (up to 6 reflow cycles) to assess the prevention of copper atoms diffusion into gold layer, solder ball pull and shear tests to evaluate the aging and long-term reliability of solder joints, and insertion loss testing to gauge whether this surface finish can be used for high-frequency, high density interconnect (HDI) applications.
Industry Directory | Equipment Dealer / Broker / Auctions
CMTec is highly specialized in dealing with assembly equipment. We support BESI (ESEC, Datacon), Kulicke & Soffa, Hesse & Knipps, F&K Delvotec, Orthodyne, ASM, Dage and others. CMTec delivers 'turn-key' projects worldwide.
Industry News | 2015-04-02 18:36:37.0
Nordson DAGE, a division of Nordson Corporation (NASDAQ: NDSN), will exhibit in Stand B-1F28 at NEPCON China 2015, scheduled to take place April 21-23, 2015 at the Shanghai World EXPO Exhibition & Convention Center. Nordson DAGE’s team of Test and Inspection experts will demonstrate the 4000Plus Bondtester and XD7600NT Diamond FP X-ray inspection system.
Used SMT Equipment | In-Circuit Testers
Gigatronics GT-1000A Overview The new Giga-tronics GT-1000A Microwave Power Amplifier offers linear high-power amplification across multioctive bandwidths. Ideal for testing in EMC, wireless communications applications, and Defense EW systems.
Used SMT Equipment | Chipshooters / Chip Mounters
(3) Fuji CP743E Chipshooters; 2003 - 2004 vintage. All consigned into the High Technology Exchange on March 12-14 on www.xlineassets.com List of additional equipment includes: TEST AND MEASUREMENT: Advantest Spectrum Analyzers Rhode and Schwa
Industry News | 2014-07-30 12:10:12.0
Nordson DAGE and Nordson YESTECH, divisions of Nordson Corporation (NASDAQ: NDSN), announce they will exhibit in Booth # A-1H30 at NEPCON South China, scheduled to take place August 26-28, 2014 at the Shenzhen Convention & Exhibition Center in Shenzhen, China.
.jpg)
