Multilevel interconnection and electrode separation technology using anodic oxidation and application to unidirectional surface acoustic wave transducers

Summary form only given. A description is given of a new multilevel interconnection using a technology in which surfaces of electrodes connected to the anodic oxidation power source are oxidized and changed to the dielectric layers. The surfaces of unconnected electrodes do not change and can be fabricated by using a simple photomask and rough mask alignment. Also described is a new electrode separation fabrication technology using a liftoff anodic oxidation method. Electrode separations are obtained using dielectric thin films fabricated by anodic oxidation of the edge of an Al film covered by the photoresist. The fabrication technology has the following merits: (1) controllable narrow gaps between electrodes with good insulation; (2) a wide electrode with small resistance; and (3) a wide photomask