| 摘要 |
<p>A transformer for high frequency applications having a multilayer thin film structure and a dielectric material disposed between coils increases the inductive coupling between the coils while at the same time reducing the capacitive coupling between the coils of the transformer. A glass substrate (201) has a first metal spiral (301) deposited thereon, and a layer of polymer insulator (601) is deposited thereon encapsulating the first metal spiral. A second metal spiral (701) is deposited on the layer of polymer and the process continues with a next layer of polymer material. The interconnection of the metal spirals to one another in the different layers is effected by the use of selectively etched grooves having vias (902) deposited therein. The present invention is specifically drawn to a balun transformer. The use of the polymer preferably BCB as the dielectric has the functional advantage of very low loss due to absorption at microwave and rf frequencies, and yet this insulator allows for excellent inductive coupling while reducing greatly the capacitive coupling among the various layers of the device.</p> |
