Reliable chronic operation of implantable medical devices such as the Utah Electrode Array (UEA) for neural interface requires elimination of transcutaneous wire connections for signal processing, powering and communication of the device. A wireless power source that allows integration with the UEA is therefore necessary. While (rechargeable) micro batteries as well as biological micro fuel cells are yet far from meeting the power density and lifetime requirements of an implantable neural interface device, inductive coupling between two coils is a promising approach to power such a device with highly restricted dimensions. The power receiving coils presented in this paper were designed to maximize the inductance and quality factor of the coils and microfabricated using polymer based thin film technologies. A flexible configuration of stacked thin film coils allows parallel and serial switching, thereby allowing to tune the coil's resonance frequency. The electrical properties of the fabricated coils were characterized and their power transmission performance was investigated in laboratory condition.

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With the current trend to ever faster clock rates the propagation delays between the chips constitute a significant portion of the clock cycle. Mounting both active and passive devices as closely together as possible will therefore boost system's performance. Although flip-chipped devices have good performance, design constraints may prevent the placement of pads to comply with flip chip design rules. An additional advantage of the embedding technology is the possibility to employ 3-D stacking, the highest package density.Bare dice and standard passive components were embedded into a ceramic substrate to achieve a common, planar surface. Hence by employing the thinfilm processing all components can be directly interconnected to the copper routing of the module. Benzocylobutene (BCB) with its low curing temperature is preferrred as dielectrical polymer for the embedding technology. Application of bonding or soldering techniques which might limit the reliability is avoided. This offers excellent electrical properties of the wiring system.By planarizing the reverse side of the MCM a low thermal resistance between heat sink and dice can be accomplished simultaneously for all embedded components.An SRAM MCM and a Themotest MCM demonstrate the facibility of the embedding technology.

For the conventional Utah Electrode Array (UEA) to be able to function without transcutaneous wire connections, a kind of power source is needed in an integrated form with the UEA. To develop such wireless neural interfaces, inductive coupling between two coils was used to deliver power to the integrated electronics. The power receiver coil was microfabricated as a polymer based component, and its electrical characteristics and performance in power transmission were investigated in dry condition