A high coercivity of up to 5.1 kOe was induced in a large-grained CoFe 2 O 4 powder after milling for a short time ͑1.5 h͒. It was found that the initial grain ͑particle͒ size played an important role in the microstructural evolution and in the magnetic properties of the milled CoFe 2 O 4 materials. The milling-induced microstructural evolution was analyzed using x-ray diffraction and transmission electron microscopy. The results indicated that the milling-induced high coercivity was associated with the highly-strained and defective microstructure. The enhancement in magnetic anisotropy was observed in large-grained CoFe 2 O 4 after milling, which might be mainly attributed to the stress anisotropy. In order to understand the coercivity mechanisms, detailed magnetic studies were carried out by the investigation of the field-dependent magnetization ͑demagnetization͒ behaviors and the magnetization reversal processes based on both the micromagnetic model and the phenomenological model. The results revealed that a domain wall pinning-controlled mechanism was responsible for the millinginduced high coercivity in CoFe 2 O 4 materials.

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In this paper, we report an advanced sample preparation methodology using in-situ lift-out FIB and Flipstage for tridirectional TEM failure analysis. A planar-view and two cross-section TEM samples were prepared from the same target. Firstly, a planar-view lamellar parallel to the wafer surface was prepared using in-situ lift-out FIB milling. Upon TEM analysis, the planar sample was further milled in the along-gate and cross-gate directions separately. Eventually, a pillar-like sample containing a single transistor gate was obtained. Using this technique, we are able to analyze the defect from three perpendicular directions and obtain more information on the defect for failure root-cause analysis. A MOSFETs case study is described to demonstrate the procedure and advantages of this technique.