The project "Autarkic Distributed Microsystems" is focused on the development of a miniaturized 3-dimensional package by using advanced assembly technologies up to wafer level assembly processes. In this connection the article points out the great potential of Flip Chip technologies, especially by using thin ICs and thin flexible substrates. Here, the flip chip contact height significantly accounts for the total module thickness. Based upon outlined standard flip chip technologies, different technological approaches towards a reduction of the contact height are presented. This includes wafer bumping, substrate generation and patterning as well as different bonding technologies. As the reliability is one of the major issues, aspects of ultra thin solder and adhesive bonding flip chip interconnections concerning this matter are mentioned. It is reported from first promising experimental results of thin flip chip solder and ultra thin ACA interconnects based on standard reliability test conditions.