Planar structures of nano-voids in volume of a crystal

Author(s):  
E.A. Stepantsov

It was studied the possibility of solid phase intergrowth of optical Y-ZrO2 crystals with preliminarily developed one of their two contacting surfaces. The developing included creation of determined relief by argon ion beam milling through a mask with determined layout. The process of solid phase intergrowth of crystals with such developed surfaces was fulfilled in the same conditions, which were used at the similar procedure for crystals with undeveloped surfaces. During the process crystal samples were put together in contact in parallel crystallographic orientation along preliminary polished and etched surfaces. Then they were heated in vacuum up to temperature 1600°С. After that they were pressed to each other up to pressure 1.4 kN/mm2 for 4 hours with further cooling with rate 10°С/min down to room temperature. Decreasing of effective square of contacting surfaces on a value of total square of etched relief picture was taken into account at calculating of compression pressure. It was found out that solid phase intergrowth on undeveloped parts of the surfaces was realized with the same result, as it was in case of solid phase intergrowth of Y-ZrO2 crystals, the contacting surfaces of which had not been developed by Ar beam milling. It was shown that nano-voids is formed at the rest parts of the contacting surfaces of crystalline specimens during their solid phase intergrowth. As a result a planar structure of nano-voids is created in a volume of a crystal, fabricated by solid phase intergrowth of two crystalline samples with preliminarily developed surface of one of them by argon beam milling through special mask. It was demonstrated that a configuration of nano-voids planar structure corresponds to a picture of the relief of the developed crystal surface with precision not worse than +/- 1 µ. By chemical etching for dislocation holes of the crystal side surfaces, which are perpendicular to a plane of a planar structure of nano-voids, it was demonstrated that during of solid phase intergrowth process plastic deformation of the material did not have place even on micro-level, corresponding to thickness of etched relief. Full absence of even weak traces of plastic deformation in the zone of crystal specimen intergrowth is an explanation of so high precision correspondance of etched relief to configuration of planar structure of nono-voids. The shown results demonstrate the possibility of creation a planar structure of nano-voids inside of a crystal, corresponding to in advance determined picture with so high precision, that it gives new possibilities in designing of photonic devices.

Author(s):  
H.-J. Ou ◽  
J. M. Cowley ◽  
A. A. Higgs

A scanning ion gun system has been installed on the specimen preparation chamber (pressure ∼5xl0-8 torr) of the VG-HB5 STEM microscope. By using the specimen current imaging technique, it is possible to use an ion beam to sputter-clean the preferred surface region on a bulk sample. As shown in figure 1, the X-Y raster-gate control of the scanning unit for the Krato Mini-Beam I is used to minimize the beam raster area down to a 800μm x800μm square region. With beam energy of 2.5KeV, the MgO cleavage surface has been ion sputter-cleaned for less than 1 minute. The carbon film or other contaminant, introduced during the cleavage process in air, is mostly removed from the MgO crystal surfaces.The immediate SREM inspection of this as-cleaned MgO surface, within the adjacent STEM microscope, has revealed the detailed surface structures of atomic steps, which were difficult to observe on the as-cleaved MgO surfaces in the previous studies.


Author(s):  
Raymond A. Lee ◽  
Patrick J. Wolpert

Abstract FIB Micromachining has long been an established technique, but until recently it has been overshadowed by the more mainstream semiconductor application of the Focused Ion Beam system. Nano- Structure fabrication using the FIB system has become more popular recently due to several factors. The need for sub-micron structures have grown significantly due to a need for enhanced optical and biological applications. Another reason for the growth in micromachining is the improvement made in the ability of FIB systems to produce geometric shapes with high precision. With the latest high-end FIB systems, it is possible to produce microstructures with tens of nano-meters of precision. Optical lens, AFM tips, and nano-apertures are all part of the growing application for FIB Micromachining. This paper will discuss the ability and limitations of the FIB system and some possible application for FIB Micromachining.


2007 ◽  
Vol 550 ◽  
pp. 289-294
Author(s):  
Suk Hoon Kang ◽  
Jae Hyung Cho ◽  
Joon Sub Hwang ◽  
Jong Soo Cho ◽  
Yong Jin Park ◽  
...  

Cold drawn gold wires are widely applied in electronic packaging process to interconnect micro-electronic components. They basically provides a conducting path for electronic signal transfer, and experience thermo-mechanical loads in use. The mechanical stability of drawn gold wires is a matter of practical concern in the reliable functioning of electronic devices. It is known that mechanical properties of materials are deeply related to the microstructure. With appropriate control of deformation and heat processes, the mechanical properties of final products, such as tensile strength and elongation can be improved. Severe plastic deformation by torsion usually contributes to grain refinement and increment of strength. In this study, microstructure variations with torsion strain followed by drawing and heat treatment were investigated. Analyses by focused ion beam (FIB) and electron backscattered diffraction (EBSD) were carried out to characterize the effect of deformation and heat treatment on the drawn gold wires. Pattern quality of EBSD measurements was used as a quantitative measure for plastic deformation.


1991 ◽  
Vol 235 ◽  
Author(s):  
D. K. Sood ◽  
V. C. Nath ◽  
Yang Xi

ABSTRACTAmorphisation of sintered SiC by bombardment with self (C, Si) ions has been studied. Ion doses ranged from 1×1015 to 1×1017 ions/cm2; and ion energy was varied from 0.09 to 5 MeV. Amorphisation was detected by micro-focus Raman scattering. Tribomechanical properties-friction and wear were studied with a high precision pin (steel ball) and disc (implanted) machine. Results show substantial improvements in friction and wear, which persist to a large number of cycles. Tribomechanical properties are shown to correlate with surface amorphisation and carburisation. Carbon ions are found to be much more effective than Si ions (with similar damage distributions) in reducing friction and wear.


2006 ◽  
Vol 960 ◽  
Author(s):  
Philipp M. Nellen ◽  
Victor Callegari ◽  
Juergen Hofmann ◽  
Elmar Platzgummer ◽  
Christof Klein

ABSTRACTWe present a closed approach towards direct microstructuring and high precision prototyping with focused ion beams (FIB). The approach uses the simulation of the involved physical effects and the modeling of geometry/topography during milling while the ion beam is steered over the surface. Experimental examples are given including the milling of single spots, trenches, rectangles, and Fresnel lenses. Good agreements between simulations and experiments were obtained. The developed procedures can also be applied to other FIB prototyping examples.


1992 ◽  
Vol 262 ◽  
Author(s):  
P. Bond ◽  
P. Sengupta ◽  
Kevin G. Orrman-Rossiter ◽  
G. K. Reeves ◽  
P. J. K. Paterson

ABSTRACTIndium Phosphide (InP) based multilayer structures are becoming increasingly important in the semiconductor industry with optoelectronic applications being the main growth area. Mesa type structures with finely controlled width and etch angle, often form the building blocks for many of these photonic devices. Traditional wet etching techniques have often proved to be inadequate for the required anisotropie removal of material. This paper presents the results of etching semi-insulating InP (100) using a combination of an Argon ion beam and a reactive gas, CCl2F2 (Freon 12). It was found that the etch rate was enhanced by increasing the ion energy and by the addition of CCl2F2. Auger electron spectroscopy revealed that the increased etch rate was accompanied by an increase in the surface indium concentration and at low ion beam energies carbon build-up retarded the etch rate. The optimum etch angle to fabricate 3μm waveguides was found to be 22° to the surface normal, however Schottky contacts to these structures were unsuccessful.


2020 ◽  
Vol 10 ◽  
pp. 34-47
Author(s):  
V. A. Gribkov ◽  
◽  
S. V. Latyshev ◽  
V. N. Pimenov ◽  
S. A. Maslayev ◽  
...  

The features of the destructive effect of high-pressure generated under comparable conditions, namely, upon irradiation of target samples with pulsed laser radiation and beam-plasma flows created in Plasma Focus (PF) devices, on metal materials were studied. In both cases, close parameters of radiation-heat treatment were provided: power density q ~ 1010–1011 W/cm2 and pulse duration τ ~ 10 –100 ns. It have been shown that the double exposure of laser radiation to thin samples of vanadium and molybdenum with a thickness of 0.3 mm and 0.1 mm, respectively, leads to the formation of molten zones in the materials, inside which there were deep craters. The craters extended over the entire thickness of the samples, on the reverse side of which the recesses end with holes of ~ 0.1 mm for V and 0.2 mm for Mo. In a tungsten sample 0.2 mm thick, the depth of the craters in the molten zone was less than its thickness and there were microcracks on the back of the sample. Based on numerical estimates of the process under study, it was suggested that the observed effects are associated with the creation of high pressure zones of ~ 1 – 10 GPa in the irradiated targets, localized in microregions of radius r ~ 0.1 mm. In these zones, the behavior of the solid phase of the target materials, for which the tensile strength σB ≤ 1 GPa (V, Mo, W), under high pressure became close to the behavior of the liquid. The pseudo-liquid phase of the material was displaced from the center of the crater, where the pressure was maximum, to its periphery to the region of low pressure with the subsequent release of matter from the target through the irradiated surface at a speed of ~ 103 m/s. In experiments using the PF, the mechanism responsible for the formation of craters when a powerful pulsed laser radiation is applied to the target is not realized due to the different nature of the distribution of the absorbed energy density in the surface layer of the irradiated sample. The region in which the energy absorbed during the of particles implantation into the material was determined mainly by the average energy and the diameter of the ion beam (Еi ≈ 100  keV, d ~ 2 – 10 mm) and exceeds by one or two orders of magnitude the corresponding volume under laser irradiation.


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