Metin Koyuncu

Chip Embedding in Laminates

This chapter provides an overview of the technology of embedding chips into laminates. The motivation, an overview of technological approaches and the challenges will be outlined. One of the technologies will be described in more detail through a case of an application. Finally a technological outlook is given in consideration of the innovations the embedded technology could make possible.

Lifetime of Poly(triaryl amine) Based Organic Field Effect Transistors under Different Environmental Conditions

Characterization of reliability and lifetime is a key issue on the way to commercialization of products based on organic electronics. Prediction of the lifetime requires the understanding of failure mechanisms and the circumstances leading to failure. In this work the stability of poly(triaryl amine) (PTAA) based organic field effect transistors (OFETs) on a poly(ethylene naphthalate) (PEN) substrate is investigated under environmental stressing. PTAA is known to form amorphous thin films after spin coating and to be air stable for extended periods of time. This inherent air stability makes it a good candidate for testing of environmental influences. The samples were electrically characterized regularly between storage cycles at 85 °C and 85 °C/85% relative humidity (RH). Samples stored under dry atmosphere and inert gas were used as reference. More than 1700 OFETs were produced in multiple batches and measured using an automated measurement system to collect statistically significant data. Circuit-relevant OFET parameters such as on- and off-current, mobility, threshold voltage and gate leakage current were extracted applying a thin film transistor (TFT) device model to the measured transfer and output curves. The threshold voltage is found to be the most sensitive parameter especially for the samples stored at 85 °C. The effect of storage under 85 °C/85%RH is observed to be comparably small. Fourier transform infrared (FT-IR) measurements of the aged OFET samples indicate a correlation between the shift of the electrical parameters and the appearance of carbonyl groups in the dielectric layer of the devices. Possible degradation mechanisms are discussed based on this observation.

Advanced interconnection technologies for flexible organic electronic systems

Flexible electronics offers high potential for innovative products by rendering electronic hardware compatible with nonplanar surfaces. Foil-based electronics, e.g. System-in-Foil, paved the way to flexible electronics products by providing a high level of packaging density as well as a means to integrate functional diversity into a single package. Components with substantially different geometrical and mechanical properties can be integrated to form a System-in-Foil, provided the integration technologies and process flow are well designed. Component diversity brings heterogeneous integration techniques into the foreground, requiring detailed consideration of the processes and materials that will provide electrical and mechanical integration between components and foils. This paper provides a survey of the various approaches and latest developments, as well as possible validation methodologies for integration technologies of flexible systems.

Reliability characterization of blind-hole vias for a System-in-Foil

In this study the bending reliability of an isotropic conductive adhesive (ICA) filled between two printed circuit foils (PCF) as interconnection for a System-in-Foil is evaluated. The filling is realized by a Jet-Dispense process on oxygen plasma treated, as well as non-plasma treated foils. The samples are tested on a bending test setup capable of real-time electrical measurements during bending. A significant improvement of the bending stability is achieved with the plasma treatment process, while the main failure mechanism for the non-plasma treated samples is delamination at the pad-adhesive interface.