摘要 |
<p>PROBLEM TO BE SOLVED: To provide an optical modulation element including a TMR element structure reduced in magnetization reversal current using MgO as a barrier layer.SOLUTION: An optical modulation element 5 includes: a TMR element structure 1 formed by stacking a magnetization fixed layer 11, a barrier layer 12 comprising MgO, and a magnetization free layer 13; and an upper electrode 3 and a lower electrode 2 connected to above and below the TMR element structure. The lower electrode 2 comprises an amorphous Cu-Cr alloy. The magnetization fixed layer 11 comprises GdFe or is formed by stacking a CoFeB layer on a TbFeCo layer. Since an MgO film as the barrier layer 12 is formed on the magnetization fixed layer 11 comprising GdFe or on the CoFeB layer, the MgO film exhibits a strong (001) plane orientation, and since the lower electrode 2 is amorphous, the MgO film is not prevented from forming a (001) plane orientation. Accordingly, magnetization reversal current in the TMR element structure 1 can be reduced.</p> |