The Planar Hall effect of Permalloy thin Films under different deposition temperatures

• Main Author: 劉家安
• Other Authors: Shien-Uang Jen
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/96680709896280988487

碩士 === 國立臺灣海洋大學 === 光電科學研究所 === 97 === Hall effect is discovered by Edwin Hall in 1879. In this thesis we illustrate that the planar Hall effect is different from Hall effect.Because add extra magnetic field parallel to the current,we can use small magnetic to measure instruments. The planar Hall effect (PHE) of Permalloy (Py) film has been employed to fabricate low-field magnetic sensors with resolutions below 10 nT. One advantage of using such sensors and devices is that they can be made at a low cost. Currently, academic institution and industry incorporate magnetic thin films into electronic devices giving rise to advanced engineering applica- tions. Among all magnetic elements, Fe20Ni80, is known with excellent magnetic properties and widely deposited on the substrate as thin film. In this research,we fabricate permalloy thin films by thermal method under different depositiontemperatures ,such as 50°C 、150°C、 350°C.Then we deposite the sample on different substrate,such as glass、Si(100)、Si(111).And we change the thin films thickness,including 300A、100A、75A and 50A.Above all,we hope to know someing different phenomenon with different parameters.Sensitivity (SH)and the temperature coefficient of resistance(TCR) are important values.Because the electronic devices need good efficiency and smooth temperature.Moreover, we also use Vibrating Sample Magnetometer (VSM) and Atomic Force Microscopy (AFM) to test and verify data right or not. Up to now, we have discovered the following results: (1) When the deposition temperature overs 300°C，sensitivity downs quickly;(2) Sensitivity has no changes when the measure temperature increases;(3) Sensitivity decreases when the thinkness increases in agreement with theory;(4) Glass sample is the most promising candidate for the PHE sensor; (5) When we measure，we know that the thinkness has limits of 75A;(6) We can not measure data because the sample has island structure condition.