US 6,816,345 B1 · Magnetoresistive sensors having submicron track widths and method of making

Abstract

Methods for reducing feature sizes of devices such as electromagnetic sensors are disclosed. A track width of a MR sensor is defined by a mask having an upper layer with a reduced width and a lower layer with a further reduced width. Instead of or in addition to being supported by the lower layer in the area defining the sensor, the upper layer is supported by the lower layer in areas that do not define the sensor width. In some embodiments the upper layer forms a bridge mask, supported at its ends by the lower layer, and the lower layer is completely removed over an area that will become a sensor. Also disclosed is a mask having more than two layers, with a bottom layer completely removed over the sensor area, and a middle layer undercut relative to a top layer.

Claims20

Dependent claims

An electromagnetic device comprising:

a plurality of adjoining sensor lay disposed adjacent to a media-facing surface,
a pair of electrically conductive layers disposed adjacent to said media-facing surface and adjoining at least one of said sensor layers,
wherein said electrically conductive layers are separated from each other by a first distance at a first location adjacent to said media-facing surface, and
said electrically conductive layers are separated from each other by a second distance at a second location within ten microns of said media-facing surface,
such that said second distance is at least twice said first distance, and
said first distance is less than one-quarter micron.

3 more elements

Dependencies are inferred from the claim text.

Magnetoresistive sensors having submicron track widths and method of making

Life of this patent

Magnetoresistive sensors having submicron track widths and method of making

Life of this patent

Abstract

Claims20