Hitachi Global Storage Technologies Netherlands B.v.

Western Digital Technologies, Inc.

Hgst Netherlands, B.v.

David Ernest Call

Hardayal Singh Gill

Jih-Shiuan Luo

Ciaran Avram Fox

Robert Langland Smith

Mike Wang

Chin-Yu Yeh

Norman Macy Tecson Libunao

Takayuki Fukumoto

A magnetic recording slider test system includes a host to collect test results and initiate concurrent testing of a plurality of magnetic recording sliders. Each of a plurality of first processing units is configured to test at least one element of a respective magnetic recording slider. In one aspect, the plurality of first processing units concurrently tests at least one element of respective magnetic recording sliders. In another aspect, a plurality of first signals is analyzed at respective first processing units, with each of the first signals representing a Direct Current (DC) output from one or more elements of a magnetic recording slider. Results determined from analyzing the first signals are sent to the host. In another aspect, a plurality of second processing units is configured to analyze second signals that each represent an Alternating Current (AC) output from one or more elements of the plurality of magnetic recording sliders.

Parallel testing of magnetic recording sliders

Structures and methods are disclosed for parallel biasing and testing, at dc and high frequency, of two or more read heads within a two dimensional magnetic recording (TDMR) slider. Testing of heads comprises both conventional tests of the individual heads within the slider, as well as tests for interactions between the heads which are very closely spaced within the slider and thus may exhibit various magnetic, capacitive, ohmic, and stress-related interactions not seen in non-TDMR heads having only a single read head. Overall testing times are nearly the same as for single head testing.

Structures and methods for parallel testing of multiple read heads in two dimensional magnetic recording sliders

A method for testing a magnetic head to determine whether the magnetic head is unacceptably affected by temperature variations. The test includes testing the magnetic head at different temperatures and measuring either or both of a signal amplitude and a signal asymmetry of a signal from the magnetic head at the different temperatures. If signal amplitude or signal asymmetry vary excessively as a result of the temperature change then the head can be scrapped.

Method for testing the acceptability of a magnetic read sensor

A method for testing magnetic heads formed on a wafer to detect the presence of thermal induced popcorn noise resulting from thermal fly height control. The method includes performing a quasi test on a magnetic head, the quasi test being performed over 400 or more cycles of magnetic field application. For additional test accuracy, the write head can be cycled while 400 or more cycles of magnetic field are generated.

Thermal fly height induced shield instability screening for magnetoresistive heads

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Folsom, CA, United States of America

David Ernest Call