Improvement of the thin film transformer characteristics by using a new fabrication process

Abstract

H.WZhang,Z.Y.Zhong.Y.L.Liu,H.C.Wang Institute of lnfmation and Mataids Udvemity of Uc=,Uonic Science and Technologl of China, Chengdu,610054,P.R.China 1.lntmductioa A great mterest har been amacted m planar magnetic devices to miniamre various electronic equipment including transformers and inductors, especially for the pwer elecuonics application[l-2]. The planar core with dgrag, spiral and wioding coil fabricated on the substrate show high core loss md large magnetic-fluxleakage because ofthe magnaic circuit was not close, meanwhile, the lithography and ion etching dry pmess are wry complexity and need lots of advanced process sysfem such as nitrogen ion beam etching system and sputterinp rystem[34]. Therefore, this paper describes a new thin film transformer fabricated by mask vacuum evaporated process. This ihm film m f o r m e r is composed of €-shaped CoZrRe amorphous magnetic l a p s wound With Cu thin film coils, primary coil fums and secandary coil bxns are 3:1,32. The measured results show that the €-Shaped thin films transformer har a high Q Value and good properties of high freauencv operation, especially in 0.5-4MHz range. 2.Experiment.l pmeedure A. Design R I R I