Back to results
US 2006/0216837 A1Published application
Method and apparatus for testing tunnel magnetoresistive effect element, manufacturing method of tunnel magnetoresistive effect element and tunnel magnetoresistive effect element
AssigneeTDK Corporation
InventorsNozomu HACHISUKA, Hiroshi Kiyono, Takeo Kagami, Kenji Inage, Norio Takahashi
Life of this patent
Estimating the term…
Abstract
A method for testing a TMR element includes a step of measuring a plurality of resistances of the TMR element by applying a plurality of voltages with different voltage values each other to the TMR element, respectively, a step of calculating a ratio of change in resistance from the measured plurality of resistances of the TMR element, and a step of evaluating the TMR element using the calculated ratio of change in resistance.
Claims54
A method for testing a tunnel magnetoresistive effect element comprising the steps of:
- measuring a plurality of resistances of said tunnel magnetoresistive effect element by applying a plurality of voltages with different voltage values each other to said tunnel magnetoresistive effect element, respectively;
- calculating a ratio of change in resistance from the measured plurality of resistances of said tunnel magnetoresistive effect element;
- and
- evaluating said tunnel magnetoresistive effect element using the calculated ratio of change in resistance.
1 more element
A method for testing a tunnel magnetoresistive effect element comprising the steps of:
- measuring a first resistance of said tunnel magnetoresistive effect element by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- calculating a ratio of change in resistance from the measured first and second resistances of said tunnel magnetoresistive effect element;
- and
- evaluating said tunnel magnetoresistive effect element using the calculated ratio of change in resistance.
1 more element
An apparatus for testing a tunnel magnetoresistive effect element comprising:
- means for measuring a first resistance of said tunnel magnetoresistive effect element by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- means for calculating a ratio of change in resistance from the measured first and second resistances of said tunnel magnetoresistive effect element;
- and
- means for evaluating said tunnel magnetoresistive effect element using the calculated ratio of change in resistance.
1 more element
A manufacturing method of a tunnel magnetoresistive effect element comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a cut process for cutting said wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested on said bar member by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of each tunnel magnetoresistive effect element;
- an evaluation process for evaluating each tunnel magnetoresistive effect element using the calculated ratio of change in resistance;
- and
- a separation process for cutting the evaluated bar member into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element.
4 more elements
A manufacturing method of a tunnel magnetoresistive effect element comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested on said wafer by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of each tunnel magnetoresistive effect element;
- an evaluation process for evaluating each tunnel magnetoresistive effect element using the calculated ratio of change in resistance;
- a cut process for cutting the evaluated wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- and
- a separation process for cutting each bar member into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element.
4 more elements
A manufacturing method of a tunnel magnetoresistive effect element comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a cut process for cutting said wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- a separation process for cutting each of said bar members into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of said tunnel magnetoresistive effect element;
- and
- an evaluation process for evaluating said tunnel magnetoresistive effect element using the calculated ratio of change in resistance.
4 more elements
A tunnel magnetoresistive effect element manufactured by a method of a comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a cut process for cutting said wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested on said bar member by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of each tunnel magnetoresistive effect element;
- an evaluation process for evaluating each tunnel magnetoresistive effect element using the calculated ratio of change in resistance;
- and
- a separation process for cutting the evaluated bar member into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element.
4 more elements
A tunnel magnetoresistive effect element manufactured by a method of a comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested on said wafer by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of each tunnel magnetoresistive effect element;
- an evaluation process for evaluating each tunnel magnetoresistive effect element using the calculated ratio of change in resistance;
- a cut process for cutting the evaluated wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- and
- a separation process for cutting each bar member into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element.
4 more elements
A tunnel magnetoresistive effect element manufactured by a method of a comprising:
- a wafer process for forming many thin-film tunnel magnetoresistive effect elements on a wafer;
- a cut process for cutting said wafer into a plurality of bar members, each of said bar members having the aligned tunnel magnetoresistive effect elements;
- a separation process for cutting each of said bar members into individual magnetic head sliders, each individual magnetic head slider having said tunnel magnetoresistive effect element;
- a measurement process for measuring a first resistance of the tunnel magnetoresistive effect element to be tested by applying a voltage with a first voltage value to said tunnel magnetoresistive effect element, and a second resistance of said tunnel magnetoresistive effect element by applying a voltage with a second voltage value of which absolute value is greater than that of the first voltage value to said tunnel magnetoresistive effect element;
- a calculation process for calculating a ratio of change in resistance from the measured first and second resistances of said tunnel magnetoresistive effect element;
- and
- an evaluation process for evaluating said tunnel magnetoresistive effect element using the calculated ratio of change in resistance.
4 more elements
Dependencies are inferred from the claim text.