Publications

10 Results
Skip to search filters

Modeling and Assessment of Atomic Precision Advanced Manufacturing (APAM) Enabled Vertical Tunneling Field Effect Transistor

International Conference on Simulation of Semiconductor Processes and Devices, SISPAD

Gao, Xujiao G.; Mendez Granado, Juan P.; Lu, Tzu-Ming L.; Anderson, Evan M.; Campbell, DeAnna M.; Ivie, Jeffrey A.; Schmucker, Scott W.; Grine, Albert D.; Lu, Ping L.; Tracy, Lisa A.; Arghavani, Reza A.; Misra, Shashank M.

The atomic precision advanced manufacturing (APAM) enabled vertical tunneling field effect transistor (TFET) presents a new opportunity in microelectronics thanks to the use of ultra-high doping and atomically abrupt doping profiles. We present modeling and assessment of the APAM TFET using TCAD Charon simulation. First, we show, through a combination of simulation and experiment, that we can achieve good control of the gated channel on top of a phosphorus layer made using APAM, an essential part of the APAM TFET. Then, we present simulation results of a preliminary APAM TFET that predict transistor-like current-voltage response despite low device performance caused by using large geometry dimensions. Future device simulations will be needed to optimize geometry and doping to guide device design for achieving superior device performance.

More Details

Heavy-Ion-Induced Displacement Damage Effects in Magnetic Tunnel Junctions with Perpendicular Anisotropy

IEEE Transactions on Nuclear Science

Xiao, T.P.; Bennett, Christopher H.; Mancoff, Frederick B.; Manuel, Jack E.; Hughart, David R.; Jacobs-Gedrim, Robin B.; Bielejec, Edward S.; Vizkelethy, Gyorgy V.; Sun, Jijun; Aggarwal, Sanjeev; Arghavani, Reza A.; Marinella, Matthew J.

We evaluate the resilience of CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) with perpendicular magnetic anisotropy (PMA) to displacement damage induced by heavy-ion irradiation. MTJs were exposed to 3-MeV Ta2+ ions at different levels of ion beam fluence spanning five orders of magnitude. The devices remained insensitive to beam fluences up to $10^{11}$ ions/cm2, beyond which a gradual degradation in the device magnetoresistance, coercive magnetic field, and spin-transfer-torque (STT) switching voltage were observed, ending with a complete loss of magnetoresistance at very high levels of displacement damage (>0.035 displacements per atom). The loss of magnetoresistance is attributed to structural damage at the MgO interfaces, which allows electrons to scatter among the propagating modes within the tunnel barrier and reduces the net spin polarization. Ion-induced damage to the interface also reduces the PMA. This study clarifies the displacement damage thresholds that lead to significant irreversible changes in the characteristics of STT magnetic random access memory (STT-MRAM) and elucidates the physical mechanisms underlying the deterioration in device properties.

More Details
10 Results
10 Results