MANASSAS, VA – A recently published study on proper flip chip cleaning confirms an optimized cleaning process will ensure all flux residues from the die-attach process be removed from the narrow capillaries between the flip chip and the substrate.
Zestron, the study’s author, found the cleaning process has to be adapted to the low standoff of flip chip components, which is influenced by bump height. Other important factors affecting the cleaning process are bump pitch and array, as well as flux type and volume, wafer passivation, and the time prior to cleaning, the firm says.
Zestron, the study’s author, found the cleaning process has to be adapted to the low standoff of flip chip components, which is influenced by bump height. Other important factors affecting the cleaning process are bump pitch and array, as well as flux type and volume, wafer passivation, and the time prior to cleaning, the firm says.
Cleaned assemblies were subjected to long-term reliability tests to determine the achieved cleanliness level, Zestron says.
SAN JOSE, CA – Worldwide semiconductor sales in October rose to $23.1 billion, an increase of 5% year-over-year, and an increase of 2% sequentially, the Semiconductor Industry Association reported today.
BANNOCKBURN, IL – October rigid PCB shipments were down 0.8% and bookings were down 1.7% year-over-year, IPC said today. Flexible circuit shipments were down 8.6% and bookings were up 0.2% year-over-year.
LOS ALTOS, CA – Third-quarter PC shipments were up 15.5% year-over-year, says research firm Henderson Ventures.
PC growth has rebounded with the help of low-cost shipments to the emerging economies, along with the slowly growing acceptance of Microsoft’s Vista operating system, and global PC shipments growth has been accelerating, reports Henderson.
For 2007, unit shipments are predicted to hit 264 million, a growth rate of 11.6%, says the firm.
The traditional two-year cycle is forecast to continue through 2009, but without a major dent in the expected growth rate for next year.
The introduction of WiMax is expected to have a positive impact on PC purchases in 2009; as WiMax becomes an accepted technology, laptop computer owners will increasingly want to acquire the capability via a new portable PC, much as PC owners traded up when WiFi became available, says Henderson.
Also, the impact of the Vista OS is likely to peak in 2009. However, global saturation, including many emerging markets, will tamp down the achievable growth rates for the foreseeable future. And even though a sizeable 10.2% increase is predicted for 2009, that pace is far below peak levels achieved in the past, including the 17.9% burst in 2005, reports the researcher.
PC growth has rebounded with the help of low-cost shipments to the emerging economies, along with the slowly growing acceptance of Microsoft’s Vista operating system, and global PC shipments growth has been accelerating, reports Henderson.
For 2007, unit shipments are predicted to hit 264 million, a growth rate of 11.6%, says the firm.
The traditional two-year cycle is forecast to continue through 2009, but without a major dent in the expected growth rate for next year.
The introduction of WiMax is expected to have a positive impact on PC purchases in 2009; as WiMax becomes an accepted technology, laptop computer owners will increasingly want to acquire the capability via a new portable PC, much as PC owners traded up when WiFi became available, says Henderson.
Also, the impact of the Vista OS is likely to peak in 2009. However, global saturation, including many emerging markets, will tamp down the achievable growth rates for the foreseeable future. And even though a sizeable 10.2% increase is predicted for 2009, that pace is far below peak levels achieved in the past, including the 17.9% burst in 2005, reports the researcher.
SCHAUMBURG, IL – Motorola announced today that chief executive Ed Zander will step down, effective Jan. 1.
TEDDINGTON, UK – A National Physical Laboratory investigation into the suitability of XRF systems for screening electronics parts found PIN (semiconductor diode) and SiLi detector-based systems suitable for RoHS compliance measurements in plastics and solders, but proportional counter based systems are not.
All systems successfully detected lead at or above 1%, the group also revealed, easily beating the 4% threshold for determining tin whisker mitigation.
The group tested 15 systems with a range of 40 typical components and assemblies. Eleven different systems were evaluated at 12 different sites. Systems based on PIN, SiLi and proportional counter detectors were included. Eleven systems were benchtop instruments; four were portable. Forty different samples were included in the study, ranging from contaminated plastic components through bulk solder alloys, to solder joints and solder-terminated components, says NPL.
XRF systems using PIN or SiLi detectors generally proved efficient at distinguishing between noncompliant components (containing typically 2000+ ppm of restricted substances) and compliant components (typically <500 ppm of restricted substances). For levels between 500 ppm and 2000 ppm, the use of additional techniques may be required to provide discrimination, NPL says.
The PIN or SiLi detectors also proved efficient at distinguishing compliant and non-compliant systems containing >1000 ppm cadmium. Below this level, however, additional techniques may again be required to provide discrimination. The lower RoHS limit for cadmium of 100 ppm did result in a number of false detections for this element, the company reports.
Proportional counter-based systems were capable of registering the presence of RoHS-banned elements at levels >3%; e.g., such as found in some plastics. Below this level, however, their ability to detect any banned substances was questionable, and use for such applications is not recommended.
For tin whisker mitigation applications, lead levels in excess of 4% are required for solder samples. All systems successfully detected lead at or above this level, provided the sample size was large enough to fill the measurement window. Indeed, all systems proved capable of detecting/measuring lead levels above 1% in solder, according to NPL.
The use of these instruments for both the applications studied (RoHS compliance or tin whisker mitigation) requires operators have both a thorough knowledge of the instrument themselves, and a good understanding of the structure and materials involved in the test samples. These are required to prevent incorrect interpretation of the data provided. Recommendations on instrument practice to obtain meaningful, repeatable results are given.
In conclusion, XRF systems offer a viable method of screening for RoHS compliance and tin whisker mitigation, says NPL. Compared to chemical analysis, these systems offer lower unit and operating cost and faster results. Smaller sample sizes are also possible. However, use of these systems does require a semi-skilled operator.
All systems successfully detected lead at or above 1%, the group also revealed, easily beating the 4% threshold for determining tin whisker mitigation.
The group tested 15 systems with a range of 40 typical components and assemblies. Eleven different systems were evaluated at 12 different sites. Systems based on PIN, SiLi and proportional counter detectors were included. Eleven systems were benchtop instruments; four were portable. Forty different samples were included in the study, ranging from contaminated plastic components through bulk solder alloys, to solder joints and solder-terminated components, says NPL.
XRF systems using PIN or SiLi detectors generally proved efficient at distinguishing between noncompliant components (containing typically 2000+ ppm of restricted substances) and compliant components (typically <500 ppm of restricted substances). For levels between 500 ppm and 2000 ppm, the use of additional techniques may be required to provide discrimination, NPL says.
The PIN or SiLi detectors also proved efficient at distinguishing compliant and non-compliant systems containing >1000 ppm cadmium. Below this level, however, additional techniques may again be required to provide discrimination. The lower RoHS limit for cadmium of 100 ppm did result in a number of false detections for this element, the company reports.
Proportional counter-based systems were capable of registering the presence of RoHS-banned elements at levels >3%; e.g., such as found in some plastics. Below this level, however, their ability to detect any banned substances was questionable, and use for such applications is not recommended.
For tin whisker mitigation applications, lead levels in excess of 4% are required for solder samples. All systems successfully detected lead at or above this level, provided the sample size was large enough to fill the measurement window. Indeed, all systems proved capable of detecting/measuring lead levels above 1% in solder, according to NPL.
The use of these instruments for both the applications studied (RoHS compliance or tin whisker mitigation) requires operators have both a thorough knowledge of the instrument themselves, and a good understanding of the structure and materials involved in the test samples. These are required to prevent incorrect interpretation of the data provided. Recommendations on instrument practice to obtain meaningful, repeatable results are given.
In conclusion, XRF systems offer a viable method of screening for RoHS compliance and tin whisker mitigation, says NPL. Compared to chemical analysis, these systems offer lower unit and operating cost and faster results. Smaller sample sizes are also possible. However, use of these systems does require a semi-skilled operator.
The work was carried out as part of a project in the materials processing metrology program of the UK Department of Trade and Industry.
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