Read Performance Reliability in TMR Head

Causes of head instability and design improvements in tunneling magnetoresistive heads are discussed. Head instability results in output signal amplitude changes and/or signal distortion due to the output noise. Under accelerated environmental conditions, a test using an original "V-H tester” was done to study and analyze the conditions of which instability occurs. From the result of the test, instability was classified into four categories. The improved sample heads were prepared, and the effectiveness was proved.