1. Solving the paradox of the inconsistent size dependence of thermal stability at device and chip-level in perpendicular STT-MRAM
- Author
-
Guenole Jan, Luc Thomas, Ru-Ying Tong, Terry Torng, Jesmin Haq, Tom Zhong, Shen Dongna, Son T. Le, Rao Annapragada, Teng Zhongjian, Renren He, Po-Kang Wang, K. Pi, Santiago Serrano-Guisan, Yu-Jen Wang, Jian Zhu, Huanlong Liu, Vinh Lam, and Yuan-Jen Lee
- Subjects
Magnetoresistive random-access memory ,Materials science ,Condensed matter physics ,Magnetic domain ,Perpendicular ,Electronic engineering ,Thermal stability ,Data retention ,Chip ,Temperature measurement ,Measure (mathematics) - Abstract
Current understanding of thermal stability of perpendicular STT-MRAM based on device-level data suggests that the thermal stability factor A is almost independent of device diameter above ∼30nm. Here we report that contrary to this conventional wisdom, chip-level data retention exhibits substantial size dependence for diameters between 55 and 100 nm. We show that the method widely used to measure A is inaccurate for devices larger than ∼30 nm, leading to significant underestimation of the size dependence. We derive an improved model, allowing us to reconcile the size dependence of A measured at device and chip level.
- Published
- 2015
- Full Text
- View/download PDF