Multi-layer double coil micro-fabricated transformer

Abstract

A novel integrated multi-layer micro-transformer is fabricated using a simple fabrication technique. The transformer consists of two coils 100 turns each with 100μm pitch. In this new technique, the primary coil is fabricated around the secondary coil, which surrounds a magnetic core. The coil tracks are fabricated using plated metal patterned using photolithography. Each layer is insulated from the other by means of a thin film of photoresist. The fabricated transformer is used in the mega Hertz range with an improvement of the coupling between its two coils compared to that of the planar spiral and solenoid transformers. © 2003 Elsevier B.V. All rights reserved.