High‐k LTCC tapes with ultralow sintering temperatures were developed from lead‐free perovskite powders. Lowering of the sintering temperature from 1250°C down to 900°C has been achieved by means of ultrafine ceramic powders in combination with suitable sintering aids. The tape‐casting process has been optimized for ultrafine powders with an enhanced sintering activity. Low‐sintering high‐k tapes of a thickness down to 40 μm, suitable for LTCC processing, were obtained. The sintering behavior of these high‐k tapes has been studied and compared with other LTCC materials. Dielectric properties of the high‐k material have been investigated on a multilayer test structure consisting of up to 20 dielectric layers. After metallization with an Ag conductor, the green tapes were stacked and laminated. Sintering of these multilayer stacks at 900°C gives dense ceramic samples. Permittivities up to 2000 have been obtained, together with low dielectric losses. Material compatibility with several Ag/Au‐thick‐film‐paste systems has been tested.

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Miniaturized video endoscopes with an imager located at the distal end and a simplified opto-mechanical layout are presented. They are based on a CMOS imager with 650 x 650 pixels of 2.8 ?m pitch and provide straight view with 75 ° and 110 ° field of view at f/4.3. They have an outer diameter of 3 mm including the shell and a length of approx. 8 mm. The optics consist of polymer lenses in combination with a GRIN and a dispensed lens. Using a simple flip chip assembly, optical axis alignment better than 10 ?m and a contrast of 30 % at 90 LP/mm was achieved. The 75 ° FOV system was sealed at the front window using a solderjetting technology, providing 10-9 mbar*l/s leakage rates even after several autoclave cycles

Rising operating temperatures, environmental restrictions, harsh conditions around our electronics, shortage of space, expectations for long-term reliability and cost are some of the driving forces we all have to deal with during electronics design. While microelectronics and semiconductor industries are running in Moore's beat bringing out impressively small analog, digital or MEMS chips, their packaging is more often the actual challenge for developers and system designers. Advancing systems-on-package, smart sensors, modules for signal processing under extreme conditions need special packaging technologies and materials as well. There, at the front of the application sector, the availability of striking silicon dies alone does not automatically deliver solutions for some advanced applications. Some of the drawbacks with traditional PCB's and housings can be resolved using ceramic boards and suitable connection technologies. A good combination of miniaturization potential and advantageous characteristics from ceramic materials is given with ceramic multilayer boards, which are available in various types. The conference lecture will show an overview about advantages and handicaps of materials, components and technologies. Traditional thick film, LTCC and HTCC as well as thin films on ceramic carriers will be illuminated in terms of pro's and con's from compatibility, cost, performance and availability points of view. Finally ceramic packages have to be technologically completed by suitable interconnection techniques, where wire bonding, adhesive bonding and soldering are just a choice of, each of them in many versions that fit to the specific requirements and to best possible connections.

RF packaging is one of the most challenging topics in LTCC technology. Today LTCC is particularly capable for advanced packages and systems-in-package because of its electrical, functional, thermomechanical properties as well as its excellent long-term stability and reliability. LTCC combines the potential for miniaturization, low loss handling of high frequencies up to 110 GHz and offers the opportunity to integrate additional features. Therefore it has to go through various manufacturing steps and several refirings without any performance degradation or loss of dimensional accuracy. This paper discusses the impact of thermal post processing on RF characteristics and geometrical properties of LTCC. Ceramic substrates with radar front ends, calibration structures and other test vehicles made of Du Pont Green Tape® 943 and 9k7 were cofired following the recommended conditions and refired several times in order to investigate and compare the influence of the postfiring. The flatness, dimensions and RF performance of the ceramics up to 110 GHz were evaluated and compared.