Large areas of perfectly ordered magnetic CoFe2O4 nanopillars embedded in a ferroelectric BiFeO3 matrix were successfully fabricated via a novel nucleation-induced self-assembly process. The nucleation centers of the magnetic pillars are induced before the growth of the composite structure using anodic aluminum oxide (AAO) and lithography-defined gold membranes as hard mask. High structural quality and good functional properties were obtained. Magneto-capacitance data revealed extremely low losses and magneto-electric coupling of about 0.9 μC/cmOe. The present fabrication process might be relevant for inducing ordering in systems based on phase separation, as the nucleation and growth is a rather general feature of these systems.

Wet etching silicon nanofins with (111)-oriented sidewalls J. Vac. Sci. Technol. B 31, 021801 (2013) Nanoscale optical critical dimension measurement of a contact hole using deep ultraviolet spectroscopic ellipsometry J. Vac. Sci. Technol. B 31, 011803 (2013) Reorganization of graphite surfaces into carbon micro-and nanoparticles under high flux hydrogen plasma bombardment J. Vac. Sci. Technol. A 31, 011303 (2013) Formation of high quality nano-crystallized Ge films on quartz substrates at moderate temperature J. Vac. Sci. Technol. B 30, 051201 (2012) Maskless fabrication of selectively sized silicon nanostructures for solar cell application Various silicon nanostructures ͑twofold chevrons and three-and fourfold spirals͒ were grown on silicon ͓111͔ substrates prepatterned with a two-dimensional square lattice of blocks with different block size and periodicity via ion beam induced glancing angle deposition at room temperature, in combination with a controlled substrate rotation. Top view and cross-section scanning electron microscopy pictures reveal that form, size, and periodicity of the structures are strongly dependent on the size and periodicity of the seeding space and differ widely from structures grown on plain substrates. It is shown that the growth of periodically arranged nanostructures, which is important for many possible applications, including photonic crystals, on prepatterned substrates is only possible if the periodicity of the seeding spaces matches the natural lateral dimensions of the structures grown on bare substrates.

The strain behavior in nanoscale patterned biaxial tensile strained Si layer on insulator is investigated in 60-nm-thick nanostructures with dimensions in the 80-400 nm range. The in-plane strain is evaluated by using UV micro-Raman. We found that less than 30% of the biaxial strain is maintained in the 200x200 nm(2) nanostructures. This relaxation, due to the formation of free surfaces, becomes more important in smaller nanostructures. The strain is completely relieved at 80 nm. This phenomenon is described based on detailed three-dimensional finite element simulations. The anisotropic relaxation in rectangular nanostructures is also discussed

A detailed knowledge of the electronic properties of individual dislocations is necessary for next generation nanodevices. Dislocations are fundamental crystal defects controlling the growth of different nanostructures (nanowires) or appear during device processing. We present a method to record electric properties of single dislocations in thin silicon layers. Results of measurements on single screw dislocations are shown for the first time. Assuming a cross-section area of the dislocation core of about 1 nm 2 , the current density through a single dislocation is J ¼ 3.8 Â 10 12 A/cm 2 corresponding to a resistivity of q ffi 1 Â 10 À8 X cm. This is about eight orders of magnitude lower than the surrounding silicon matrix. The reason of the supermetallic behavior is the high strain in the cores of the dissociated dislocations modifying the local band structure resulting in high conductive carrier channels along defect cores.

We present a comparative study of the influence of the thickness on the strain behavior upon nanoscale patterning of ultrathin strained Si layers directly on oxide. The strained layers were grown on a SiGe virtual substrate and transferred onto a SiO(2)/Si substrate using wafer bonding and hydrogen ion induced exfoliation. The post-patterning strain was evaluated using UV micro-Raman spectroscopy for thin (20 nm) and thick (60 nm) nanostructures with lateral dimensions in the range of 80-400 nm. We found that about 40-50% of the initial strain is maintained in the 20 nm thick nanostructures, whereas this fraction drops significantly to approximately 2-20% for the 60 nm thick ones. This phenomenon of free surface induced relaxation is described using detailed three-dimensional finite element simulations. The simulated strain 3D maps confirm the limited relaxation in thin nanostructures. This result has direct implications for the fabrication and manipulation of strained Si nanodevices.