Abstract
We are developing fully implantable wireless brain-machine interface system, which is able to record up to 4096ch ECoG signals. In this system, ECoG signals are amplified and digitized by an LSI. The neural data are transmitted to a wireless devise. Then, they are transmitted from inside to outside of the body wirelessly. One problem of this system is that the parts between multi-channel electrodes and wireless transmitter are too large to implant in head. To miniaturize this part, we propose the direct integration of electrodes and LSIs. The purpose of this study is to make a prototype of 1024ch ECoG electrode array with LSIs, to complete the wireless BMI system and to evaluate its performance in vivo experiment. We designed a 64ch electrode using flexible printed circuit technology. The substrate of the electrode was made of flexible thin-film polyimide and a 64ch LSI was flip chip bonded to it. After the measurements of fundamental properties such as impedance, we united the sixteen 64ch electrodes with LSIs into one 1024ch electrode with LSIs. We are planning to evaluate the performance of the electrode by an acute animal experiment.
