A growing need is developing in the high-speed digital arena (backpanels,motherboards,line cards etc) for materials offering sufficient signal integrity for applications up to 10 Gbps. One solution is a PTFE/ fiberglass/thermosetting resin composite1 that can be processed at conventional PCB pressures and temperatures. Because the PTFE can be applied in a high volume process by a PTFE processor and the thermosetting resin can be applied in a large scale manufacturing process using commercial treaters,the volume manufacture of PTFE based laminates can be achieved in a cost effective fashion. The prepregs and laminates are based on a PTFE/fiberglass/BT-epoxy composite that is treated with 10-40 wt% of a thermosetting resin. The resulting composite has demonstrated signal integrity in a 20 layer backplane that is very competitive relative to a pure PTFE/fiberglass construction2. The hybrid has a very low dissipation factor when 15-40 wt% thermosetting adhesive is used (0.004-0.005 at 14.5 GHz). The PTFE/fiberglass/BT-epoxy composite provides good bonding to substrates at conventional processing temperatures,gap filling of 2 oz circuitry,very high thermal stability,and predictable movement. Preliminary results suggest that the materials drill better than standard PTFE boards.

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All-aromatic polyester,one of the super engineering plastics,is highly regarded as a base material of electronic circuit for its environmental compatibility,moisture resistance,dimensional stability and heat resistance. With Type I all-aromatic polyester having the highest heat resistance of the three types of aromatic polyesters,we succeeded in making it into a film material with a highly controlled orientation. This liquid crystal polymer film,hereinafter referred to as LCP FILM (I),has great solder heat resistance up to 280?C and high dimensional stability. Its Coefficient of Hygroscopic Expansion is 1.5 ppm/% and the Coefficient of Thermal Expansion is controllable to match with that of copper foil (16ppm/ ?C). In addition,LCP FILM (I) has very low water absorption of 0.1%,which is approximately 1/10 that of polyimide film,and shows great performance in a high frequency range. It is also notable that LCP FILM (I) is a recyclable material as its raw material is thermoplastic resin. Having these advantages,applications of LCP FILM (I) have been expanded to PWB and IC packages for IT-related devices that require HDI and high frequency performance.

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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.