-
- News
- Books
Featured Books
- smt007 Magazine
Latest Issues
Current IssueBox Build
One trend is to add box build and final assembly to your product offering. In this issue, we explore the opportunities and risks of adding system assembly to your service portfolio.
IPC APEX EXPO 2024 Pre-show
This month’s issue devotes its pages to a comprehensive preview of the IPC APEX EXPO 2024 event. Whether your role is technical or business, if you're new-to-the-industry or seasoned veteran, you'll find value throughout this program.
Boost Your Sales
Every part of your business can be evaluated as a process, including your sales funnel. Optimizing your selling process requires a coordinated effort between marketing and sales. In this issue, industry experts in marketing and sales offer their best advice on how to boost your sales efforts.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - smt007 Magazine
News
December 31, 1969 |Estimated reading time: 7 minutes
Compiled By SMT Staff
U.K. Survey Determines Lead-free Readiness
SURREY, United Kingdom — The Reliability and Failure Analysis group of ERA Technology has received support from the ERA Foundation to carry out a survey to determine the state of readiness within the U.K. industry for the transition to lead-free.
The European Union (EU) will ban the sale of products containing lead-based solders effective July 1, 2006. Because no existing satisfactory lead-free solders currently can be used as a replacement, manufacturing techniques will have to be adapted, and in some cases, different components will have to be used. By the date of the ban, U.K. companies must identify the most appropriate lead-free solder materials, design new products and modify existing ones, optimize production processes, commission new equipment (if necessary), test products for reliability, and eliminate all stock of lead-based products.
The company already has performed a preliminary survey to gauge the depth of the problem. Results indicate that while most small printed circuit board (PCB) manufacturing companies surveyed had begun thinking about the subject, most have not started working on the change. The attitude among the preliminary survey companies was that the issue will move to the front once customers begin asking for lead-free products.
The results of the main survey will be used to determine best practice, highlight future problems, identify training needs and help U.K. companies meet the EU deadline. ERA will disseminate survey results through seminars, conferences and the company's Web site, www.era.co.uk.
Orbotech New President Barry Cohen
BILLERICA, Mass. — Orbotech Inc., a leader in automated optical inspection (AOI) systems for bare printed circuit boards (PCB) and flat panel displays (FPD), appointed Barry Cohen president and CEO effective January 1, 2003.
Cohen jointed Orbotech in 1994 as eastern regional manager. Later he was promoted to vice president of sales for the PCB division, and most recently he held the position of vice president of electronics assembly. Cohen continues to be based at the company's North American headquarters in Billerica, Mass.
Cohen replaces Shabtai Shaanani, who completed his three years with the company.
Miniature Components
WEYMOUTH, DORSET, United Kingdom — Tecan Components Ltd., a photo-chemical machining specialist, has breached traditional manufacturing obstacles to deliver low-cost micro-metal parts and larger parts with ultra-fine features for a new applications arena covering electronics, optical, medical and aerospace.
The advantages of the technology are expected to be used by a wide range of industries for demanding next-generation micro-applications, in which products will be made significantly smaller and finer, repeatedly, at lower cost, and with few production processes.
Typical micro-applications include sensors, actuators, optical instruments and more. Micro-structures can be manufactured to extremely small scale with features such as apertures, fluid channels or raised lands down to 1 to 2 µm, with tolerances at submicron levels. They also will be used in microelectromechanical systems (MEMS) and micro-opticalelectromechanical structures (MOEMS). Similarly, the company can produce parts up to 12 x 12" with equally fine resolutions.
Tecan describes the new technology as the hybrid application based on three established manufacturing technologies — silicon semiconductor, high-volume audio CD, and micro-embossing tools such as those used in micro-lens array and hologram manufacture.
PCB Book-to-Bill Ratio
Book-to-Bill Sees Major IncreaseNORTHBROOK, Ill. — The U.S. IMS/PCB Industry Book-to-Bill Ratio for January 2003 was 1.02, meaning $1.02 worth of orders for new boards were received for every $100 billed (shipped). The ratio increased dramatically from the December 2002 level of 0.96. Sales billed (shipments) in January 2003 decreased 19.8 percent from January 2002 and orders booked decreased 16.4 percent from January 2002. Compared to 2002, bookings of PCBs are up 3.9 percent year-to-date, while shipments of PCBs are down 1.3 percent year-to-date.
January's book-to-bill level increased dramatically from December numbers, while orders booked for January 2002 increased 3.9 percent year-over-year.
null
Q & A: Wire bonding
Q: A customer recently asked, "With some of our new products incorporating chip-on-board (COB) technology, we occasionally experience problems with wire bonding. There is occasionally lot-to-lot variation. What can cause this?"
A: Incorporating a packaging technology like wire bonding with SMT provides a common design solution needed to meet product demands such as size, weight and performance. In this particular case, the stated problem from the customer was that wire bonding was possible on some of the board lots, while other lots failed to provide proper bonding of the gold wire to the PWB. The task of the analysis was to 1) measure and compare the composition and thickness of each board lot, 2) determine if impurities were present in the different metal layers, and 3) determine if nickel and/or copper was migrating through the top gold layer.
The initial analysis began with scanning electron microscopy (SEM) of representative samples to understand what surface impurities may be present that would affect wire bonding. Cross sectioning, SEM and energy dispersive spectroscopy (EDS) were also performed on samples from each of the lots. The samples were sectioned down to the suspected bond pad locations, followed by imaging and elemental analysis. From these analyses, thickness measurements were obtained.
Four lots were evaluated, and samples from only one lot indicated no presence of nickel or copper on the top bond pad surface. However, samples from this lot die exhibited a slightly high level of carbon presence. All the other PWB lots were determined to exhibit some trace of copper and/or nickel presence. One lot exhibited traces of copper presence, but no nickel. Since no nickel was detected, it is unknown if the copper presence was migrating through the layers. One sample indicated a presence of carbon and oxygen, which could be representative of an organic contamination on the bond pad surface. IR microscopy would need to be performed to verify the existence and composition of any suspect organic presence. There exhibited a wide range of gold thickness across the lots (39, 102, 192 and 227 µm). Other than the first lot, all of these gold thickness measurements are acceptable for gold wire bonding.
High levels of nickel presence can cause wire bond adhesion problems if the layer becomes oxidized before bonding. Plasma etching of the bond pad surface would be necessary to allow an adequate bond to occur. However, it is imperative that the nickel and gold layer thicknesses are kept within specification. A thick gold layer (>50 µm) can help assure control of the nickel.
Elemental analysis of the cross-sectioned samples revealed that three lots had no traces of nickel or copper in the top half of the gold region. One lot exhibited a high presence of nickel (34 percent) in the gold region.
In empirical studies, it was noted that the poor wire bond results were related to those samples exhibiting the minimum gold thickness, as well as the samples present with carbon/oxygen signatures during elemental analysis. These two factors are known to create wire bonding instability on PWB surfaces.
Regardless of how well the bond equipment variables are controlled, poor bond adhesion will occur without properly designing and controlling the PWB's bond pad surface.
Craig Beddingfield is senior market and business development manager and Brian Lewis is development engineer for SiemensDematic Electronics Assembly Systems Inc., Norcross, Ga.
TI's Logic Devices Now Lead-free
DALLAS — As a leading supplier of lead-free electronic integrated circuit (IC) packages, Texas Instruments (TI) announced that its complete logic portfolio now is available in lead-free solutions. TI has used lead-free finishes for numerous logic packages since the late '80s, and now has converted 100 percent of its logic portfolio to improved lead-free finishes and balls. By implementing these strategic finishes and balls, TI logic packages are classified per the J-STD-020B (maximum reflow temperature of 250°C) lead-free parameters.
Lead Frame Packages. TI has chosen the nickel/palladium/gold (Ni/Pd/Au) finish as the preferred lead-free finish for all lead frame-based packages. Two major customer concerns driving the decision to use the Ni/Pd/Au finish were compatibility with lead-free solders and tin whisker growth.
Ball Grid Array (BGA) Packages. TI also has qualified lead-free ball alloys for its LFBGA, VFBGA and WCSP logic packaging offerings. The MicroStar BGA, MicroStar Jr. BGA and NanoFree Logic packages all use Sn/Ag/Cu alloys. Sn/Ag/Cu alloys are the lead-free choice in the industry for BGA packages.
The higher melting point of lead-free Sn/Ag/Cu solder alloys compared to Sn/Pb demands higher peak reflow temperatures in lead-free soldering processes.
All TI Logic Products lead frame packages are available in the Ni/Pd/Au finish and rated for use in lead-free processes per J-STD-020B. Other lead-free options can be supplied upon demand for packages scheduled for conversion to Ni/Pd/Au finish by 2Q 2003.
Machine Vision Standard
SAN JOSE, Calif. — New analysis from Frost & Sullivan (F&S), "World Machine Vision Inspection Systems Market," reveals that the industry-generated revenues totaled $1.12 billion in 2002. Total market revenues could reach as high as $2.62 billion in 2009.
The lack of operating standards within the machine vision industry creates difficulties in developing and operating vision systems, said an F&S research analyst. Conflicts between components, computer software and hardware technologies, and user interfaces reduce industry credibility because no plug-and-play exists for a generic system.
While the industry is working toward making machine vision technology irreplaceable in inspection and quality control processes, R&D budgets are likely to be strained. End users want systems based on technology that is more robust, have greater potential applications and add value. Simpler user interfaces that allow system integration, regardless of the level of technical knowledge, also are in demand. Other areas that need additional focus include optical character and pattern recognition algorithms, resolution, and image mapping.