公开(公告)号：US5514953A

公开(公告)日：1996-05-07

申请号：US437692

申请日：1995-05-09

申请人： Allan E. Schultz ,  Peter K. George ,  William P. Wood ,  Duane C. Phinney ,  Patrick J. Ryan

发明人： Allan E. Schultz ,  Peter K. George ,  William P. Wood ,  Duane C. Phinney ,  Patrick J. Ryan

IPC分类号： G01N27/82 ,  G01R33/09 ,  G11B5/31 ,  G11B5/39 ,  G11B5/455 ,  G01R33/12 ,  H01L43/08

CPC分类号： G11B5/397 ,  G01N27/82 ,  G01R33/09 ,  G01R33/096 ,  G11B5/455 ,  G11B5/3166 ,  G11B5/3189 ,  Y10T29/49004

摘要： A wafer level test structure and method detects multiple magnetic domains and magnetic domain instability in a test magnetic element. The apparatus comprises a first MR sensor designed to be held in a single magnetic domain by shape anisotropy and a second MR sensor having a permanent magnet to hold the element in a single magnetic domain. A circuit connects the first and second MR sensors to detect differences between the changes in resistance between the first and second sensors in the presence of a magnetic field or differences in resistance after the application and release of a magnetic field. The circuit is preferably a balance circuit in which imbalance in the presence of a magnetic field indicates the presence of multiple magnetic domains in at least one of the test sensors. Magnetic domain stability may be tested by applying an external field to disrupt the existing single domain state of the test sensors, and thereafter detecting differences in resistance of the sensors during reversal of the magnetic field.

摘要翻译： 晶圆级测试结构和方法检测测试磁性元件中的多个磁畴和磁畴不稳定性。 该装置包括被设计为通过形状各向异性保持在单个磁畴中的第一MR传感器和具有永磁体以将元件保持在单个磁畴中的第二MR传感器。 电路连接第一和第二MR传感器，以在存在磁场或施加和释放磁场之后的电阻差时检测第一和第二传感器之间的电阻变化之间的差异。 该电路优选地是其中存在磁场的不平衡指示在至少一个测试传感器中存在多个磁畴的平衡电路。 可以通过施加外部场来破坏测试传感器的现有单域状态，然后在磁场反转期间检测传感器的电阻差异来测试磁畴稳定性。