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Spin-orbit torques arising from the spin-orbit coupling of non-magnetic heavy metals allow electrical switching of perpendicular magnetization. However, the switching is not purely electrical in laterally homogeneous structures. An extra in-plane magnetic field is indeed required to achieve deterministic switching, and this is detrimental for device applications. On the other hand, if antiferromagnets can generate spin-orbit torques, they may enable all-electrical deterministic switching because the desired magnetic field may be replaced by their exchange bias. Here we report sizeable spin-orbit torques in IrMn/CoFeB/MgO structures. The antiferromagnetic IrMn layer also supplies an in-plane exchange bias field, which enables all-electrical deterministic switching of perpendicular magnetization without any assistance from an external magnetic field. Together with sizeable spin-orbit torques, these features make antiferromagnets a promising candidate for future spintronic devices. We also show that the signs of the spin-orbit torques in various IrMn-based structures cannot be explained by existing theories and thus significant theoretical progress is required.

The microstructure of ultrafine grained low carbon steel processed with repetitive equal channel angular pressing was investigated. A submicron ferrite grain size of ∼0.2 μm was achieved by pressings of up to 12 passes. Microstructural examination by TEM with SAD pattern on the pressed samples revealed the presence of high density dislocations inside the ferrite grains and ill-defined grain boundaries. These features became more significant as the number of pressings increased. The static annealing of the pressed samples at 753 K up to 24 hrs resulted in a recovery which was associated with the absorption of the dislocations by the grain boundaries. However, the recovery was inhibited as the number of pressings increased. The annealing process also led to the precipitation of cementite particles in ferrite colonies. The presence of precipitated particles inside the ferrite grains enhanced the microstructural stability of the low carbon steel at elevated temperatures.

We investigate boron transient enhanced diffusion (TED) and series resistance in SiGe/Si heterojunction channel pMOSFET. The stress gradient at the SiGe/Si interface near the gate edge in high Ge concentrations are found to determine boron TED as well as extension junction shape, which has a significant impact on the parasitic LDD and source/drain (S/D) series resistance. In addition, high Ge concentrations in the epitaxial SiGe layer on top of Si substrate result in a high sheet resistance during a 1000°C/5s rapid thermal processing (RTP), which is mainly due to alloy scattering and interface roughness scattering.