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Stress Analysis of Failure Mechanisms to Power Modules Reliability 19/10/2011

Power electronic moduleswhich have highly inhomogeneous structures are combined by semiconductors, ceramic, copper, aluminum, polymers and sometimes composite materials. These materials are assembled together in the packaging manufacturing process using soldering, direct bond copper (DBC), wire bonds, and pressure contact interconnection techniques. Power modules are widely used in alternative energy generation aerospace, automotive and distribution applications. They play an important role in the conversion, control and delivery of electrical power.
Power module contains a number of materials. With different coefficients of thermal expansion (CTE), these materials together with a number of interfaces, wear out and over- stress failures could occur. Power cycling is the typical accelerated test procedure used to qualify power electronics components where the package will be subjected to cyclic DEVICEtemperature changes over time. These result in fluctuating strain and stress magnitudes being induced on the packaging materials, leading to failures. With future trends in power electronics toward ever greater currents passing through the components and ever smaller spatial profile, the packaging structure and its ability to withstand the stresses imposed on it will become an important factor in power electronics module reliability.
Reliability is the probability that a device will perform its required function under stated conditions for a specific period of time. Therefore the reliability specifications of power electronic modules in sectors such as aerospace, computers, auto- motive, etc., are different due to differences in the external environment and expected lifetimes of the product in these sectors. A reliability prediction estimates the reliability of the power electronics module as used in the field. This depends on the design of the power module and the in-service environmental conditions it is subjected to during its lifetime. Many companies still adopt the handbook methods for reliability prediction to calculate mean time between failures. This calculation is based on individual failure rates for each component making up the device which are statistically obtained from field data. It is well documented that this technique can result in very poor predictions.
Failure mechanisms is a good way to predict the reliability of power electronic modules The physics of failure approach to reliability predictions requires models that predict the stresses imposed on the packaging materials when the device is operational and subjected to external environmental conditions.
By using finite element analysis or other modelling techniques, stress analysis can be undertaken. These techniques predict the strains and stresses in the materials at locations where failures are likely to occur. In addition to these modeling techniques the physics of failure approach requires lifetime models whose inputs would come from the predictions from the above stress analysis. These damage models will predict the lifetime of each of the structures that make up the power electronics module. These will subsequently aid the design engineer to identify which component will fail first when subjected to particular environmental and operating conditions. It should be noted that physics of failure lifetime models have the ability to predict the number of cycles to failure when the package is subjected to qualification testing (i.e. power cycling) or the expected operational life of the package when the operational life can be quantified in terms of operational cycles. Having accurate physics of failure lifetime models also allows the design engineer to rank different failures for particular loading conditions and potentially to identify the acceleration factors between accelerated testing and field behavior.

Tags : Stress Analysis - Failure Mechanisms - Power Modules - reliability

Global Solar Module Stock Soared 19/10/2011

Solarbuzz pointed out that, in the first half of 2011, the weak European market demand to solar energy led to the global solar module stock soared in the second quarter.
 Manufacturer had forecast the second quarter of 2011 the shipment will increase 12% on the previous quarter, however, according to Solarbuzz preliminary estimates, the actual shipment rate reduced 22%, even if the second quarter demand has increased to 79%, and the production was down 20%, battery and module manufacturers inventory still increased 559 MW.
By positive renewable energy quotas (RPS) target policy incentives, California accounts for 62% of the total installation of the United States now. Renewable energy quotas policy has become the main driving force of states solar project plan, the first six states are California, Arizona, Nevada, New Jersey, New Mexico and Texas, and 40 states are expected to have installed solar power project.
Rapid development of the non-residential project create important growth opportunities for developers and contractors, Solarbuzz's statistics show that, so far, the first 12 largest project occupies 49% of the overall amount project not installed. Solarbuzz points out, the past four months, the factory prices of module crash until now only started to affect large project price. In more than 1 MW plan project, the average price for each system installation is $4.5/w, 32% of the project price is under $4 per watts.
Compared with the prediction of 2GW in2011 in the United States overall demand, 17 GW preinstalled quantity still face great challenges. The most remarkable challenges include project structure and the source of funds integration, overcome regulations change and make full use of the recent market price trend to purchase the best combination of solar system components. From module and inverter suppliers who choose preinstall project to see, the first three modules suppliers are First Solar, Sun Power and Suntech, the leading suppliers of the inverter are Advanced Energy and Sat Con Technology.

Tags : Solar Module - stock - soar

Mobile Phone Pushes the Growth of Its Related Devices 19/10/2011

It is expected that the mobile devices will held the booming growth till 2016 with a shipment of750 million, at the same time, it will drive the growth in mobile processor, with 300 million tablets, 100 million e-readers and 91 million handheld game consoles also expected to ship that year.

Market research IDC has said it expects total smartphone sales in 2011 to reach 472 million globally, while tablets are predicted to ship 53.5 million by year's end. A recent report by E-Ink also predicted the number of E-book reader sales in 2011 would reach between 20-25 million units.

The processors powering these mobile devices will be truly amazing, consuming remarkably little power, built in the latest nanometer technology, and delivering unbelievable performance and functionality. More than 2 billion mobile processors will be shipped in 2016, to quench the seemingly insatiable thirst for handheld devices. Combined, smartphones and tablets will account for more than 50 % of the mobile processors shipped that year. 

Of course, with the increasing demands users are placing on their handsets for more computer-like productivity and multi-functionality, integrated circuits are an integral part of the mobile handset semiconductor market especially. In addition, another recent study from In-Stat says it expects the mobile market for merchant processing to grow at a 22.3 % compound annual growth rate through 2013, with the highest total unit growth from handheld applications like smartphones and tablets.

As a result, the estimated value of the processing, graphics/multimedia and baseband functions will also increase at double-digit growth rates, with processors garnering the highest value at $33.1 billion, according to analyst estimates. More than16 processor companies and four IP suppliers will be chasing this market, compared to the four or five processor companies chasing the PC market. What's interesting is how various semiconductor companies have reacted to this market and how it's changing the whole dynamics of the industry, noting that just 3 years ago it would have been downright bizarre to imagine Intel threatened by ARM and its chip alliance, including the likes of Qualcomm, Nvidia and Texas Instruments, or the fact that AMD would be a complete non-player in the mobile market.

The battle could eventually cross platform lines if Intel ever manages to crack the mobile nut with its upcoming lower powered x86 processors, but  currently ARM Holdings plc's architecture still dominates the handheld space and doesn't look remotely close to relinquishing its crown any time soon. Market dynamics on pricing has changed as well. Intel and AMD could still sell $200-$300 chips, but relatively few compared to the massive number of mobile ships in the $20-$50 range. The volume will be huge and the margins will be lower, but the overall revenues will be massive.

As long as consumers continue to push for mobile video, music, advanced gaming, imaging, videoconferencing and television in the palm of their hand, however, Moore's Law will continue to drive transistor characteristics to smaller design geometries and transistor densities to new highs, which may prove tough for some semiconductor firms to keep up with. That isn't to say there won't be a market for lower end mobile devices, however, even feature phones will continue to see major growth, with some 869 million units predicted to ship in 2016.

Tags : Mobile Phone - mobile processor

The Behind Secret of China PCB Industry 18/10/2011

The electronicequipment is inseparable from the PCB, from electronic watches, calculators, general computer to newsletter electronic equipment and military weapon system; as long as there is integrated circuit and other electronic devices, the PCB should be used. It provides integrated circuit, etc. various kinds of electronic components of fixed assembly mechanical support to realize integrated circuit for all sorts of electronic components of wiring and electrical connection between electric insulation, required electrical characteristics, such as characteristic impedance. At the same time, it provides resistance welding graphics for automatic soldering; and provides identification characters and graphic for components cartridge, inspection, and maintenance.
Follow the development process, the rapid development of chinese PCB industry from small to large, from weak to strong, has put the China as the world's top PCB output country, and with the strong momentum of development to impact the world PCB industry high-end fields.
Applications: emerging electronic products push flourishing PCB market

Printed circuit board as the load substrate and key interconnection pieces of electronic parts, any electronic equipment or products are needed to have. Its downstream industry coverage is quite widespread, involving general consumer electronics, information, communication, and even aerospace science and technology products, etc. With the development of science and technology, various products of electronic information processing demand gradually increased, emerging electronic products are constantly emerging; making PCB products market growth expanded greatly. The new 3 G mobile phone, automobile electronics, LCD, IPTV, digital TV, computer updating will bring more larger PCB market than traditional market.
Looking back the whole PCB industry's development path, strong trend let PCB market with unlimited business opportunities. Although in recent years, pressure of the raw material costs is rising, consumer electronics market will promote the PCB industry into a new stage of development.

Industrial transfer brings up China PCB market
China PCB began in 1956. From 1963 to 1978, China gradually expanded the PCB industry. From 1978-1998, because of the introduction of foreign advanced technology and equipment, the single panel, double panel and multilayer prototypes have got rapid development. In recent years, with HDI, as a representative of the high density multilayer prototypes also get rapid development.
From a global perspective, China mainland PCB is still the most prominent. Mainland China in 2003 surpassed the United States to be the third in the world. In 2006, China become the world's first. It is predicted that 2014 mainland China PCB production value will achieve 31.45 billion dollars, with a compound annual growth rate of 14.7%, which accounted for more than 45.6% in the global. Global PCB production value in 2014 is expected to reach $69 billion in all, compound growth rate will arrive at 9.5%. In addition to the mainland China, South Korea and other Asian countries (mainly including Thailand, Vietnam, Singapore, Malaysia and the Philippines, etc) are growing more quickly, the compound annual growth rate will reach 11.82% and 10.24% respectively.

Smart phones popularization helps the PCB industry to grow faster
In 2010 global 1.5 billion mobile phone, mainland China produced 900 million pieces; this is also the important reason of the Chinese mainland HDI board fast growth. In 2010 the global HDI board production value reached $12.52 billion, including $3.75 billion in Japan as the first, mainland China for 3.74 billion dollars, almost equal with Japan. Mainland China in 2001 output value of HDI board was only $120 million, increasing more than 30 times in 10 years. China Taiwan is $2.422 billion; South Korea is $1.82 billion. The United States, Europe and other regions HDI plate output is very small, the annual output value is only $235 million, $200 million and $353 million respectively.
It is noted that in 900 million mobile phone of China mainland, a big part of it is "emulational mobile phone". “It also will bring the opportunity to the PCB industry to. At the same time, along with iPhone, HTC as a representative of the popular smartphone market, promote the development of the PCB industry faster. Growing popularity of the smart phone not only become a new fashion, but also brought a lot of orders for PCB electronic consumer manufacturers.

The PCB industry meets environmental protection test
China has become a global big printed circuit board producers, the environmental and resources and the sustainable development is put in unprecedented strategic height.
PCB production may have a serious pollution to the environment. If pollution condition doesn't change, the future development of the PCB industry is concerned. In the past few years, a lot of PCB enterprise invested a lot of manpower and material resources in control pollution and circular economy.

Tags : China - PCB - Smart phones

Where Apple iPhone A6 Chip Will Return 18/10/2011

The A6 processorsare destined to go into the next iteration of the Apple smartphone. Apple will continue relying on Samsung's foundry operation to use Samsung's chips and technology for its next smartphone, which may or may not be named the iPhone 5.

Though these two companies have battles, Samsung Electronics and Apple are expected to maintain their relationship as chip supplier and buyer. Samsung offers better pricing and capacity commitment for the A6 mobile APs.

There had been speculation that Apple would shift its chip sourcing channel to Samsung rival Taiwan Semiconductor Manufacturing (TSMC). It is reported that Samsung Electronics will apply its advanced 28-nanometer processing technology to produce qualified A6 mobile APs. TSMC will provide customized chips with designs from Apple; however, the volume will be very small.

The ongoing chip talks between Samsung and Apple were revealed that Samsung is handling legal issues involving Apple independently of its business relationship with the company. Apple still views Samsung as a critical parts supplier because Samsung capability to manufacture customized chips on a foundry or contract basis gives it an advantage that TSMC and other rivals cannot currently match. Apple will become Samsung's biggest overseas client by the end of this year, according to industry analysts, after buying over $8 billion worth of components including liquid crystal displays (LCDs) and memory chips.

Industry sources believe that the next version of the iPhone will feature a 4-inch LCD screen, 0.5 inch larger than the recently-unveiled iPhone 4GS, and they will continue to be provided by LG Display. The iPhone 5 will feature a similar resolution to the iPhone 4, which are 960x640 pixels. It's very unlikely that Apple will go for organic light emitting diode (OLED) displays considering the problems related to brightness and battery consumption.

LG Display has been the provider of “Retina Display'' screens that have been used in Apple's mobile products. The screen provides a high-level of picture density that makes it hard to see the pixels. It is said that Apple was providing up to 15 percent of LG Display's total revenue by the end of the first quarter of this year. With a bigger screen, the surface design of the iPhone 5 will be changed. The iPhone 5 and iPad 3 will be launched within the first quarter of next year.

With Apple using quad-core mobile APs in the next iPhone, South Korean handset majors including Samsung, LG and Pantech are expected to adopt the same technology for their new smartphone models to offer a faster processing speed.

Tags : Apple iPhone - A6 Chip - Samsung