Non-destructive imaging for quality assurance of magnetoresistive random-access memory junctions

TY - JOUR

T1 - Non-destructive imaging for quality assurance of magnetoresistive random-access memory junctions

AU - Jackson, Edward Alan

AU - Wu, Yifan

AU - Frost, William James

AU - Kim, Jun-Young

AU - Samiepour, Marjan

AU - Elphick, Kelvin

AU - Sun, Mingling

AU - Kubota, Takahide

AU - Takanashi, Koki

AU - Ichinose, Tomohiro

AU - Mizukami, Shigemi

AU - Hirohata, Atsufumi

N1 - © 2019 IOP Publishing Ltd

PY - 2019/10/16

Y1 - 2019/10/16

N2 - We have developed a new non-destructive sub-surface interfacial imaging technique. By controlling the penetration depth of the incident electrons, through control of the electron beam acceleration voltage in a scanning electron microscope, we can observe sub-surface interfaces. The voltages for imaging are selected based on Monte Carlo electron flight simulations, where the two voltages have >5% difference between the number of backscattered electrons generated in the layers above and below the buried interface under investigation. Due to the non-destructive nature, this imaging method can be used alongside an applied electrical current and voltage, allowing concurrent observations of the interfacial structures and transport properties, e.g., effective and active junction area, to occur. Magnetic tunnel junctions used in magnetic random access memory have been imaged and the data has been fed back to improve their fabrication processes. Our imaging method is therefore highly useful as both a quality assurance and development tool for magnetic memory and nanoelectronic devices.

AB - We have developed a new non-destructive sub-surface interfacial imaging technique. By controlling the penetration depth of the incident electrons, through control of the electron beam acceleration voltage in a scanning electron microscope, we can observe sub-surface interfaces. The voltages for imaging are selected based on Monte Carlo electron flight simulations, where the two voltages have >5% difference between the number of backscattered electrons generated in the layers above and below the buried interface under investigation. Due to the non-destructive nature, this imaging method can be used alongside an applied electrical current and voltage, allowing concurrent observations of the interfacial structures and transport properties, e.g., effective and active junction area, to occur. Magnetic tunnel junctions used in magnetic random access memory have been imaged and the data has been fed back to improve their fabrication processes. Our imaging method is therefore highly useful as both a quality assurance and development tool for magnetic memory and nanoelectronic devices.

U2 - 10.1088/1361-6463/ab47b6

DO - 10.1088/1361-6463/ab47b6

M3 - Article

SN - 1361-6463

VL - 53

JO - Journal of Physics D: Applied Physics

JF - Journal of Physics D: Applied Physics

M1 - 014004

ER -