Abstract: A method of fabricating a magnetic device is described. A mask removing layer is formed on a layered sensing stack and a hard mask layer is formed on the mask removing layer. A first reactive ion etch is performed with a non-oxygen-based chemistry to define the hard mask layer using an imaged layer formed on the hard mask layer as a mask. A second reactive ion etch is performed with an oxygen-based chemistry to define the mask removing stop layer using the defined hard mask layer as a mask. A third reactive ion etch is performed to define the layered sensing stack using the hard mask layer as a mask. The third reactive ion etch includes an etching chemistry that performs at a lower etching rate on the hard mask layer than on the layered sensing stack.

Abstract: The present invention provides a thin-film structure that includes an etch-stop layer having a first side and a second side, a patterned compensation layer for dissipating thermal energy, and an etch-vulnerable layer, where the etch-stop layer substantially impedes etching. The patterned compensation layer is adjacent the first side of the etch-stop layer, and the etch-vulnerable layer is adjacent the second side of the etch-stop layer.