Abstract: A method for forming a bi-layer lift-off mask, including a hardened photoresistive stencil layer on a PMGI layer, for use in fabricating GMR read-head sensors with trackwidths of less than 0.1 microns and TMJ MRAM devices of similar critical dimensions. The stencil portion of the mask includes a narrow portion with sharply defined edge and corners which are formed, without rounding or extreme undercut, by a photolithographic process which includes the formation, in a first development process, of auxiliary pattern pieces over the corners of the stencil and a subsequent oxidation in ozone for removing those auxiliary pattern pieces and obtaining sharply defined edge and corners and a controlled dissolution of the PMGI layer.

Abstract: A method for forming a big-layer lift-off mask for use in fabricating GMR read-head sensors with trackwidths of less than 0.1 microns. The mask layers are formed symmetrically on each other, each layer of the mask having a novel dog-bone shape and the lower mask layer being substantially undercut relative to the upper mask layer. The central portion of the lower mask layer forms a narrow ridge that maintains the upper mask layer at a fixed height above a substrate, thereby avoiding problems associated with big-layer lift-off masks of the prior art. The method of forming the lower ridge requires a carefully controlled undercutting of the lower mask layer, which is accomplished by using an ozone-assisted oxidation process.

Abstract: The present invention provides a coil structure capable of improving a differential transmission characteristic by reducing capacitance as much as possible. A common mode choke coil is constructed so that a section of each of two coil patterns constructing a thin film coil has an inverted trapezoid shape which is bilaterally asymmetrical. Because of the structural characteristic that the section of each of the two coil patterns has an inverted trapezoid shape which is bilaterally asymmetrical, the facing area of the two coil patterns contributing to capacitance is minimized. Thus, the capacitance of the thin film coil can be reduced as much as possible.

Abstract: A method for forming a bi-layer lift-off mask, including a hardened photoresistive stencil layer on a PMGI layer, for use in fabricating GMR read-head sensors with trackwidths of less than 0.1 microns and TMJ MRAM devices of similar critical dimensions. The stencil portion of the mask includes a narrow portion with sharply defined edge and corners which are formed, without rounding or extreme undercut, by a photolithographic process which includes the formation, in a first development process, of auxiliary pattern pieces over the corners of the stencil and a subsequent oxidation in ozone for removing those auxiliary pattern pieces and obtaining sharply defined edge and corners and a controlled dissolution of the PMGI layer.

Abstract: The present invention provides a coil structure capable of improving a differential transmission characteristic by reducing capacitance as much as possible. A common mode choke coil is constructed so that a section of each of two coil patterns constructing a thin film coil has an inverted trapezoid shape which is bilaterally asymmetrical. Because of the structural characteristic that the section of each of the two coil patterns has an inverted trapezoid shape which is bilaterally asymmetrical, the facing area of the two coil patterns contributing to capacitance is minimized. Thus, the capacitance of the thin film coil can be reduced as much as possible.

Abstract: A method for forming a bi-layer lift-off mask for use in fabricating GMR read-head sensors with trackwidths of less than 0.1 microns. The mask layers are formed symmetrically on each other, each layer of the mask having a novel dog-bone shape and the lower mask layer being substantially undercut relative to the upper mask layer. The central portion of the lower mask layer forms a narrow ridge that maintains the upper mask layer at a fixed height above a substrate, thereby avoiding problems associated with bi-layer lift-off masks of the prior art. The method of forming the lower ridge requires a carefully controlled undercutting of the lower mask layer, which is accomplished by using an ozone-assisted oxidation process.