Thin film thermocouple sensors for measurement of contact temperatures during slider asperity interaction on magnetic recording disks

Thin film thermocouple sensors have been fabricated on a magnetic recording slider. Both sensor and the reference junctions are located on the air bearing surface of the slider. The effective size of the junctions is 4 micrometer and response time is faster than 0.5 microsec. The sensitivity of these thermocouples is measured to be 7 microV/degrees C. The thermocouple signals obtained at the slider asperity contacts show temperature rise of 1-5 degrees C. Incorporating the sensor dimensions and assuming asperities of 0.5 micrometer width, we estimate the actual temperatures to be in the range of 90 - 450 degrees C.