Medical devices need a maximum of miniaturization for highest functionality in smallest volumes. An approach using ultra-thin highly flexible substrate technology, flip chip reflow soldering of thinned IC dies thereon and 3D-folding and stacking has been tested in the framework of the European project TIPS. The concepts of ultra-flexible and ultra-thin embedded medical devices on large area panels are proposed in this paper. Application fields of such highly integrated modules are strongly growing areas like medical and health monitoring, both for implanted and non-implanted medical devices, sensors, portable and wearable electronic systems. A folded thin flex module containing a hearing aid flip-chip-set has been realized as a demonstrator.