Nanoprobing on a MRAM cell, following a backside opening, to extract data information

Thursday, November 16, 2023: 2:50 PM
103 A-B (Phoenix Convention Center)
Mrs. Louise Dumas , Centre National d'Etudes Spatiales (CNES), Toulouse, France
Dr. Guillaume Bascoul , Centre National d'Etudes Spatiales (CNES), Toulouse, France
Dr. Christina Villeneuve-Faure , Université de Toulouse, Toulouse, Occitanie, France
Dr. François Marc , University Bordeaux 1, Talence, Nouvelle Aquitaine, France
Dr. Hélène Fremont , University Bordeaux 1, Talence, Nouvelle Aquitaine, France
Mr. Christophe Guerin , Direction Générale de l’Armement (DGA), Bruz, Bretagne, France

Summary:

The direct measurement of the memory state (i.e. bit at “0” or at “1”) on single magnetic tunnel junction (MTJ) in a commercial magnetic random access memory (MRAM) remain challenging. In this paper, we propose a nanoprobing approach to investigate the MTJ resistance and by this way determined the memory state. To reach this goal, the MRAM device needs to be prepared to create an electrical access to both sides of the MTJs. The suitable methodology consists in a backside preparation routine that creates a bevel allowing us to access the bottom side of the MTJs through vias and the top side to the bitlines. After that, the electrical connection is created by two nanometric tips positioned in contact via vias and bitlines thanks to Scanning Electron Microscope (SEM). It is then possible to collect the current flowing through the MTJs and to evaluate the resistance.