Verification of a fabrication process used to form read elements in magnetic heads
View Patent ↗Test methods and components are disclosed for testing the quality of a fabrication process used to form read elements in magnetic heads. A wafer is populated with one or more test components along with magnetic heads. The test components are formed by the same or similar fabrication processes as the read elements, but do not include a conductive MR sensor between the test leads. By measuring the resistance of the test components, the formation of parasitic shunts can be identified in the test components, which may indicate the formation of parasitic shunts in the read elements. Thus, the quality of the fabrication process in forming read elements in magnetic head may be determined.
1. A method of testing the quality of a fabrication process used to form read elements in magnetic heads on a wafer, the method comprising:
fabricating a test component on the wafer along with the magnetic heads, the test component including:
a first test lead;
a second test lead; and
at least hard bias magnet material and insulating material between the first test lead and the second test lead,
wherein the test component is fabricated to not include a magnetoresistance (MR) sensor;
measuring a resistance of the test component to identify parasitic shunts between the first test lead and the second test lead; and
determining the quality of the fabrication process based on the measured resistance of the test component.
2. The method of claim 1 wherein fabricating a test component comprises:
fabricating a plurality of test components staggered throughout the wafer.
3. The method of claim 1 wherein fabricating a test component on the wafer along with the magnetic heads comprises:
fabricating the test component concurrently with fabricating the magnetic heads.
4. A test component on a wafer of magnetic heads, the test component comprising:
a first test lead;
a second test lead; and
at least hard bias magnet material and insulating material between the first test lead and the second test lead,
wherein the test component is fabricated to not include a magnetoresistance (MR) sensor.
5. The test component of claim 4 wherein the first test lead and the second test lead allow a probe to measure a resistance to identify parasitic shunts between the first test lead and the second test lead.