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The change in resistance (dR) due to an applied high voltage pulse is a measure ofthe electrostatic discharge susceptibility ofa resistor. The influence ofthe pulse width and height on the susceptibility was investigated on thickfilm chip resistors of different values and sizes. By means ofthe transmission line pulsing technique (TLP), the ESD behaviour ofthickfilm chip resistors is presented.

We present technological results on the embedding of ultra-thin microcontroller ICs in flexible film substrates. The novel concept is based on the following technologies: face-up chip mounting in cavities on film laminates, photo-lithographic patterning of vias and interconnects embedding in polymer layer and compatibility with both sheet and roll-to-roll processing. The paper briefly reviews the benefit of embedding for ultra-thin dies in terms of mechanical robustness. For the technological demonstration, we used 25μm thin microcontroller IC and 50μm polyimide film substrates. Electrical interconnections were realized by sputtering of metal layers. Photolithography was performed on “wafer level” using aligner photomasks and a photo-sensitive polymer of 10μm thickness for embedding. The embedding process resulted in a mechanically flexible fan-out chip package of a thickness below 100μm. Perspectives and technological requirements for roll-to-roll manufacture as well as cost estimation for this kind of Thin Chip Foil Package are explained and discussed. Furthermore, we report our recent work on the development of an in-situ bending and electrical test equipment for flexible film modules. The new set-up was evaluated using ultra-thin test chips with daisy chain patterns that were ACA flip-chip bonded onto Polyimide films. It was found that reducing the chip thickness from 28μm to 12μm lead to a strong increase in mechanical strength of the chip-on-film (COF) assemblies tested under recurrent bending

One of the most important issues of resistors properties is the value stability under different electrical and non electrical influences. Mechanical andlor thermal stress together with the electrical one represents the main factors that have a major contribution in resistor value stability. With shrinking resistor geometries of discrete, integrated and integral passives, the electrical stress gains more and more importance, especially under short duration voltage pulses. The analytical test technique of Transmission Line Pulsers (TLP) allows, on the basis of square pulses, the in-situ monitoring of the voltages and currents at the DUT during pulsing and helps to gain fundamental insights into the electrical behavior. The influence of the pulse width and height on the current-voltage behavior was investigated on thickfilm chip resistors of different values and sizes. The resistance change due to an applied high voltage pulse is a measure of the Electro Static Discharge (ESD) susceptibility ofthickfilm resistors.