21pm3-PM009 MRI画像計測のための双円錐型立体マイクロコイル

抄録

This paper reports on a bicone-shaped micro coil for measuring NMR (Nuclear Magnetic Resonance) signals of MRI (Magnetic Resonance Imaging). The three dimensional bicone-shaped micro coil was fabricated by pushing and folding a pair of planar coils by using MEMS (Micro Electro Mechanical Systems) technology. Since the gap between Cu wires of the coil increases by using the bicone-shaped structure, this coil has low parasitic capacitance and high self-resonant frequency. Furthermore, the structure of the coil is suitable for small spherical samples, because the coil has high sensitivity due to the close distance between coil wirings and samples. We fabricated the coils of three different numbers of turns, 6-turn, 8-turn, and 10-turn. The parasitic capacitances of 6-turn, 8-turn, and 10-turn bicone-shaped coils were 0.254 pF, 0.322 pF, and 0.426 pF, respectively. At the voxel size of 200×200×200 μm^3, SNRs of 6-turn, 8-turn, and 10-turn coils were 94.7, 101.8, and 79.1.