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Advances in information/communications technology are transforming the Internet from a medium for searching for information into a medium for providing and receiving various types of information and services. As the number of users and the variety of services continue to grow,there are increasing demands for a more comfortable environment--an environment that allows "quicker on demand access to more information,which is presented with better realism." In order to make such an (Internet) environment a reality,we need to be able to exchange a large amount of information within a short space of time. This in turn makes it necessary to accelerate signal speed,or to increase the signals frequency. Printed wiring boards used for handling high-frequency signals are required to have lower levels of transmission loss so as to maintain and ensure signal quality. From the viewpoint of copper foil,which provides the basis of conductive trace,the main concerns are as follows: (1) increases in conductor loss (one of the factors behind transmission loss) and (2) declines in bonding strength to resin (declines in trace bonding strength) resulting from reductions,(which is intended for minimizing dielectric loss),of the dielectric constants and dissipation factors of substrates. This paper discusses the findings of our examination of the issues above.

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With the advent of digitisation,networking,broadband telecommunication,and miniaturization in electronic set products,electronic devices are essentially required to deliver high electrical and mechanical performance that correspond with this trend. From its first introduction in 1996,Any Layer IVH structure ALIVH has been serving the mobile phone application as its core business market but has since diversified into several other markets. Therefore,I would like to give an introduction,along with an update on the status of ALIVH for motherboard use and the technological development and trends of our extended range of new products such as ALIVH -B,ALIVH (G-type),etc

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The growing use of high density interconnect (HDI) substrates in the microelectronics packaging industry has brought along a broad range of yield issues. Many of these issues are associated with surface defects in the interconnect terminals and solder mask areas of the finished substrates. Detecting such defects requires a different set of capabilities than that of traditional Automated Optical Inspection (AOI) tools used for in-process inspection. These differences result in particular from the surface integrity specifications of the interconnect terminals,and the subjectivity of defect severity. This paper presents examples of defects and discusses inspection capabilities required to detect and classify them correctly. It examines the factors affecting detection capability and false alarms,and proposes a simplified method for system performance evaluation and setup optimization.

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It is becoming impossible to realize the latest mobile phones and other mobile equipment without Chip Size Packages (CSP) and other high-density semiconductor package technology. At present,the most advanced mobile phones in the world are being made in Japan with a compact size and lightweight,but these rely for the most part on chip stacked CSP technology. This paper describes how mobile phone packaging technology has changed in Japan,from 1996 to 2001-2002,and how packaging is being done in the most recent mobile phones. In preparation for the coming era of 3-D System In Package (3-D SIP),this paper also describes the kind of technologies that are possible today,and how they will develop in the future.

Liquid crystalline polymer (LCP) substrates offer a number of advantages for high-density packaging. These properties include high temperature capability (>250oC),low coefficient of thermal expansion (8ppm/ oC),low moisture permeability (comparable to glass),smooth surface,and good high frequency characteristics. LCP substrates can be fabricated as flexible films (2mil thick) or as rigid multilayer substrates. In this paper the processing of rigid and flexible LCP substrates are first discussed including etching,drilling,and plating. Next,the compatibility of LCP substrates with wire bond and flip chip assembly processes and materials are examined. Specific tests include solderability with eutectic Sn/Pb and lead-free alloys,surface insulation resistance with no clean fluxes,gold wire bondability and flow/wetting of underfills for flip chip assembly. The high temperature capability of the LCP is compatible with the higher reflow temperatures associated with lead–free solders and also allows thermosonic gold wire bonding at a substrate temperature of 200oC. Solder dips in lead free alloys at 274oC have shown no delamination of the copper foil. Gold ball shear test results demonstrate average shear strength of 62.4 grams with a standard deviation of 4.3 grams when bonded at 200oC. Optical fibers can be molded into the LCP substrate for optical connections and optical fibers can also be molded into the package sidewall for optical connections. Finally,hermetic packages have been fabricated and shown to pass fine and gross leak tests.