Hexagonally ordered nanohole patterns were produced on Ge(100) surfaces by focused Ga+ ion beam and broad Ga+ ion beam irradiations with 5 keV energy under normal incidence. Identical patterns were obtained by irradiations with a scanning focused ion beam under different irradiation conditions and with a broad Ga+ beam without scanning and five orders of magnitude smaller ion flux. Thus, we could demonstrate that nanohole pattern formation is independent of ion flux over several orders of magnitude and scanning of a focused ion beam under appropriate conditions is identical to broad ion beam irradiation.

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The native extracellular matrix (ECM) laid down on silicon and titanium surfaces by osteoblast-like SAOS-2 cells was exposed by selective removal of cells. This type of material surface ECM-Si, ECM-Ti was shown to promote the nucleation of calcium phosphate from a simulated body fluid (SBF). Microscopic and spectroscopic results revealed the effect was associated with a collagen fiber-free extracellular matrix.

Conventional annealing processes such as furnace annealing ͑FA͒ and rapid thermal annealing ͑RTA͒ are compared to the more advanced technique of flash lamp annealing ͑FLA͒ regarding the electroluminescence ͑EL͒ efficiency, electrical stability, defect formation, and rare-earth nanocluster ͑RE-nc͒ creation in metal-oxide-silicon-based light-emitting diodes with Gd implanted SiO 2 layers. We observed strong correlation between the electroluminescence efficiency, the nanocluster size, and the annealing technique for Gd implanted oxides. The increase of the annealing temperature and time leads to an increase of the RE-nc size and decreases the EL efficiency. Therefore, short-pulse high-temperature annealing ͑FLA͒ has a large advantage over the different annealing techniques ͑FA and RTA͒ from the point of view of stable and efficient metal oxide semiconductor light emitters.Silicon dioxide is one of the most technologically important wide-gap optical materials. Especially in its amorphous form ͑a-SiO 2 ͒, it plays a crucial role in many of today's technologies, including medical applications, as the gate and passivation oxide layers in more than 90% of the all metal-oxide-semiconductor ͑MOS͒ devices. 1 Combining silicon-based electronic circuits with optoelectronic functionality is one of the key challenges for the future semiconductor technology. Light emitters based on rare-earth Er 3+ , Tm 3+ , Tb 3+ , and Ce 3+ doped Si-rich SiO 2 have been reported with emission in the infrared to blue-green spectral range. 2,3 Recently, a silicon-based efficient UV light emitter based on a SiO 2 :Gd MOS structure with a sharp emission peak at 316 nm from Gd 3+ ions was reported by Sun et al. 4 During processing, the excellent dielectric properties of amorphous silica are perturbed by ion implantation and as a consequence of ion-solid interaction various types of defects are created ͑oxygen deficient centers ODC, nonbridging oxygen hole centers NBOHC, EЈ-centers, etc.͒. Post-implantation annealing techniques are widely used to remove the damage induced by ion implantation and to activate the implanted centers both in amorphous and crystalline matrices. Nevertheless, the long term hightemperature annealing process is responsible for further defect generation, 5 rare earth nanocluster formation, 6 and the diffusion of implanted elements. 7 The reduction of the annealing time of metal-oxide-silicon-based light-emitting diode ͑MOSLED͒ structures is important from the viewpoint of their industrial application as well as the underlying physics. Recently, there have been reports on the importance of short annealing times in the msec range for the formation of ultrashallow junctions in advanced technologies 8 as well as modeling 9 and other advanced applications. 10 In this paper, we report on the advance of using short-pulse high-temperature flash lamp annealing ͑FLA͒ compared to the more conventional annealing techniques ͑furnace annealing, FA and rapid thermal annealing, RTA͒ regarding the formation of more efficient MOS-based light ...

A systematic study on structural defect buildup in 320 keV Ar-ion bombarded GaN epitaxial layers has been reported, by varying ion fluences ranged from 5 × 10 12 to 1 × 10 17 at./cm 2. 1 µm thick GaN epitaxial layers were grown on sapphire substrates using the metal-organic vapor phase epitaxy technique. Rutherford backscattering/channeling with 1.7 MeV 4 He beam was applied for analysis. As a complementary method high resolution transmission electron microscopy has been used. The later has revealed the presence of extended defects like dislocations, faulted loops and stacking faults. New version of the Monte Carlo simulation code McChasy has been developed that makes it possible to analyze such defects on the basis of the bent channel model. Damage accumulation curves for two distinct types of defects, i.e. randomly displaced atoms and extended defects (i.e. bent channel) have been determined. They were evaluated in the frame of the multistep damage accumulation model, allowing numerical parameterization of defect transformations occurring upon ion bombardment. Displaced atoms buildup is a three-step process for GaN, whereas extended defect buildup is always a two-step process.