Pillar Type Research Articles

Mechanical Responses of Copper Bicrystalline Micro Pillars with Σ3 Coherent Twin Boundaries by Uniaxial Compression Tests

Two types of bicrystalline micro pillars (BCMs) involving ­3 coherent twin boundaries along the pillar axis and single-crystalline micro pillars of two grains constituting the BCMs were fabricated in an oxygen-free copper sample by focused ion beam milling. These pillars were compressed using a nanoindenter to investigate slip transfer across grain boundary (GB). Referring their stress­strain (SS) curves, the possible slip systems were resolved from scanning electron microscope images after deformation and GB interaction criteria with the three largest Schmid factors (SFs) of each grain and the geometric relationship of intersections between the slip planes and the GB. The quite different SS behaviors were observed in the two types of BCMs, of which one was the unstable elastic-almost perfect plastic deformation due to large strain bursts and the other was work-hardening accompanying several small strain bursts. The slip transfer analyses suggest that the slip directions of both grains with the maximum SF are almost parallel to GB plane to the former behavior, and the combination of three slip systems from both grains produces the terraced hardening with repeated slipping across GB and piling-up against GB to the latter. [doi:10.2320/matertrans.MA201312]

Pillar Type Silicon-Oxide-Nitride-Oxide-Silicon Flash Memory Cells with Modulated Tunneling Oxide

In this paper, we fabricated 3D pillar type silicon-oxide-nitride-oxide-silicon (SONOS) devices for high density flash applications. To solve the limitation between erase speed and data retention of the conventional SONOS devices, bandgap-engineered (BE) tunneling oxide of oxide-nitride-oxide configuration is integrated with the 3D structure. In addition, the tunneling oxide is modulated by another method of <TEX>$N_2$</TEX> ion implantation (<TEX>$N_2$</TEX> I/I). The measured data shows that the BE-SONOS device has better electrical characteristics, such as a lower threshold voltage (<TEX>$V_{\tau}$</TEX>) of 0.13 V, and a higher <TEX>$g_{m.max}$</TEX> of 18.6 <TEX>${\mu}A/V$</TEX> and mobility of 27.02 <TEX>$cm^2/Vs$</TEX> than the conventional and <TEX>$N_2$</TEX> I/I SONOS devices. Memory characteristics show that the modulated tunneling oxide devices have fast erase speed. Among the devices, the BE-SONOS device has faster program/erase (P/E) speed, and more stable endurance characteristics, than conventional and <TEX>$N_2$</TEX> I/I devices. From the flicker noise analysis, however, the BE-SONOS device seems to have more interface traps between the tunneling oxide and silicon substrate, which should be considered in designing the process conditions. Finally, 3D structures, such as the pillar type BE-SONOS device, are more suitable for next generation memory devices than other modulated tunneling oxide devices.

Lab on a chip for in situ diagnosis: From blood to point of care.

As the point of care diagnosis devices are becoming ever more popular, this paper suggest a miniaturized testing device from a drop of blood to diagnosis of disease for the global healthcare. The minimal requirements for the POC blood-testing device are blood microsampling, blood separation, immunoassay, and detection and communication of the signals. The microsampling of the blood can be achieved by specialized needle, which can be connected to the microchip or analytical devices. The sampled blood is then separated using either a filter (weir or pillar type), or by the phenomena unique to microfluidic system. The separated blood should then go through sandwich, homogeneous non-competitive, or competitive immunoassay, which can effectively diagnose diverse diseases. Lastly, the device should detect and translate the immune-signals to readable, and clinically significant signals. The development of such device will play a great role for improving healthcare technology.

Processing of silicon nanostructures by Ga+ resistless lithography and reactive ion etching

Ga^+ resistless lithography and subsequent reactive ion etching (RIE) with SF6 and C4F8 as process gases have been applied to fabricate silicon nanostructures with main emphasis on arrays of pillar type structures usable as nanoelectrodes. The strongly reduced etching rate of silicon areas implanted with Ga by focused ion beam (FIB) irradiation compared to unaffected silicon is investigated in dependence on the implanted dose and compared to literature. A certain dose range is found to result in an optimum masking effect whilst obtaining very smooth surfaces after RIE. As is demonstrated surfaces implanted with lower doses exhibit high roughnesses after RIE. Thus, patterning of 3D structures due to greyscale Ga^+ resistless lithography seems questionable. Depending on the RIE process parameters, however, for a given FIB mask pattern the lateral dimension of the final nanostructures can be varied in a wide range enabling very small pillar diameters or line widths due to underetching. Such structures exhibit aspect ratios well above 10 and lateral dimensions of slightly below 20nm as demonstrated within this work. First results for the removal of the Ga implanted masking layer are presented, too. Finally, the potential and performance of Ga^+ resistless lithography compared to the fabrication of nanoelectrode structures by direct FIB milling is critically discussed.

Thermo-mechanical analysis of TSV and solder interconnects for different Cu pillar bump types

Graphical abstractDisplay Omitted Highlights? FE modelling of Cu pillar bumps of different types. ? Stress distribution in solder interface and TSV interface. ? Reliability of conical frustum type is excellent than other types. The through silicon via (TSV) is a technology for vertical interconnection between multiple chips that employ a hole bored through a Si wafer and stack chips, which is good for securing a number of I/O per unit area reducing the electric resistance. On the other hand, vertical multi-layers are structurally more unstable than a single-layer but are vulnerable to a thermo-mechanical effect. Therefore, in this study, finite element analysis (FEA) of a three-dimensional (3D) multi-layer semiconductor with TSV was carried out to examine the changes in thermo-mechanical stress at the bonding interface with different models of Cu pillar bumps and Sn-3.5Ag solder bumps. A numerical simulation was carried out with different models, such as a plate type, pin type, skirt type, zigzag type and conical frustum type. The height and diameter of each solder bump were 10µm and 30µm, respectively. The distribution of Von Mises stress occurred more at the solder joint interface and TSV joint interface. At the solder joint interface, the stress in the skirt type (100.6MPa) was approximately double that in the conical frustum type (53.1MPa). At the TSV joint interface, the stress in the plate type (17.2MPa) was higher than that in the other types. The stress values were similar in the other types except for plate type Cu pillar bump. Stress in the solder and TSV joint interface was caused partly by the difference in properties between the two materials. In particular, mismatch in the coefficient of thermal expansion (CTE) had the greatest effect on the stress distribution.

A Prospective Multicenter Study of Legg-Calvé-Perthes Disease

Long-term studies have indicated good outcomes for most patients with Legg-Calvé-Perthes disease. However, clinical experience suggests that less favorable outcomes are common. We sought to prospectively document pain and function in a cohort of adults who had previously been treated nonoperatively for Legg-Calvé-Perthes disease. Patients in our region with Legg-Calvé-Perthes disease were enrolled between 1984 and 1991 as part of a multicenter prospective trial and were treated with hip range-of-motion exercises or bracing. Patients returned for physical examination, radiographs, and completion of outcome measures including the Nonarthritic Hip Score (NAHS) and the Iowa Hip Score (IHS). Fifty-six patients (fifty-eight hips) were examined at a mean of 20.4 years (range, 16.3 to 24.5 years) after enrollment. The mean NAHS was 79 (range, 35 to 100), and the mean IHS was 74 (range, 43 to 100). Three patients had required hip arthroplasty and one patient had required a pelvic osteotomy. Fourteen (26%) of the remaining hips had no hip osteoarthritis, sixteen (30%) had mild osteoarthritis (Tönnis grade 1), and twenty-four (44%) had moderate or severe osteoarthritic changes on radiographs (grade 2 or 3). Femoroacetabular impingement indicated by physical examination was associated with pain and with poorer outcomes on the IHS and the NAHS (p = 0.0004, 0.0014, and 0.0007, respectively). The Stulberg classification was significantly associated with impingement on physical examination (p = 0.0495), the NAHS (p = 0.003), and the Tönnis grade (p = 0.012). Multivariate logistic regression showed that only the Stulberg classification was significantly associated with the NAHS (p = 0.0032); the odds ratio for a Stulberg type of I or II compared with IV or V in patients with a fair or poor NAHS was 0.101 (95% confidence interval, 0.018 to 0.573). Pain, arthritis, and ongoing hip dysfunction are common in patients with Legg-Calvé-Perthes disease that was treated nonoperatively. Hips rated as Stulberg type III or IV more frequently had poor or fair outcomes on the IHS and NAHS (61% and 72% for type III and 77% and 60% for type IV). Patients with a lateral pillar type of B, B/C, or C frequently had pain and radiographic evidence of osteoarthritis. Clinical signs of femoroacetabular impingement were associated with pain and with lower functional scores. This prospective study establishes a modern benchmark for outcomes following nonoperative, weight-bearing treatment of Legg-Calvé-Perthes disease.

Adsorption and catalytic properties of Fe/Cr-pillared bentonites

This paper presents a study of the adsorption and catalytic properties of bentonites pillared with iron (Fe), chromium (Cr) and iron/chromium pillars with different Fe/Cr molar ratios and calcined at 350°C. The carbon dioxide (CO2) and hydrogen (H2) adsorption properties exhibited by the pillared bentonites were studied. The highest CO2 and H2 adsorption capacities for the Fe/Cr-pillared bentonite sample with a Fe/Cr molar ratio of 1/9 (Fe/Cr0.1–PB) were 0.691 and 0.791mmol/g, respectively. The equilibrium data for the CO2 and H2 adsorptions were analysed using the Freundlich, the Langmuir and the Redlich–Peterson isotherm models. The results were used to estimate the adsorption parameters and relate them to the pillar type. The results show that the CO2 and H2 adsorptions of the pillared samples follow different isotherm equations. The catalytic activity was evaluated for the catalytic wet peroxide oxidation of phenol. The highest catalytic activity was observed for the Fe/Cr0.1–PB sample; a 100% phenol conversion was achieved in 4h using the experimental conditions of t=30°C, pH 3.7 and mcat=5g/L. Using the same catalyst, the oxidation rate of phenol increased when the temperature was raised from 30°C to 50°C; this increase is a result of the higher H2O2 decomposition and OH− production rates. The oxidation rate of phenol also increased when the initial pH was raised from 3.7 to 5.

Comparative Analysis of Bandgap-Engineered Pillar Type Flash Memory with HfO&lt;sub&gt;2&lt;/sub&gt; and S&lt;sub&gt;3&lt;/sub&gt;N&lt;sub&gt;4&lt;/sub&gt; as Trapping Layer

In this paper, we fabricated a gate-all-around bandgap- engineered (BE) silicon-oxide-nitride-oxide-silicon (SONOS) and silicon-oxide-high-k-oxide-silicon (SOHOS) flash memory device with a vertical silicon pillar type structure for a potential solution to scaling down. Silicon nitride (Si3N4) and hafnium oxide (HfO2) were used as trapping layers in the SONOS and SOHOS devices, respectively. The BE-SOHOS device has better electrical characteristics such as a lower threshold voltage (VTH) of 0.16V, a higher gm.max of 0.593µA/V and on/off current ratio of 5.76×108, than the BE-SONOS device. The memory characteristics of the BE-SONOS device, such as program/erase speed (P/E speed), endurance, and data retention, were compared with those of the BE-SOHOS device. The measured data show that the BE-SONOS device has good memory characteristics, such as program speed and data retention. Compared with the BE-SONOS device, the erase speed is enhanced about five times in BE-SOHOS, while the program speed and data retention characteristic are slightly worse, which can be explained via the many interface traps between the trapping layer and the tunneling oxide.

Arthroscopic Classification of Suprapatellar Plica and Medial Synovial Plica

In the previous arthroscopic studies, the ratio of presence and type of plica was somewhat different. We arthroscopically investigated and classified suprapatellar plica and medial synovial plica in a Japanese population. Subjects and Methods: The anatomy of suprapatellar plica and medial synovial plica was studied arthroscopically in 130 knees. Original diagnosis of patients included in this study were 53 meniscal injuries, 51 ACL injuries, 17 osteoarthritis, 5 popliteal cysts, 3 osteochondritis dissecans, and 1 synovial osteochodromatosis. Results: The suprapatellar plica was present 73.8% and classified into 6 types which were arch type, medial type, lateral type, perforated type, pillar type and complete type. The medial synovial plica was present 62.3% and classified into 4 types which were narrow type, medium type, broad type and perforated type. No relationship between age and the pattern of the suprapatellar plica or medial synovial plica could be found. There was no trend to be correlation between the type of suprapatellar plica and medial synovial plica. Conclusion: We classified suprapatellar plica by only location and shape of plica and medial synovial plica by the size of plica.

SPATIAL BEAM COMPRESSION AND EFFECTIVE BEAM INJECTION USING TRIANGULAR GRADIENT INDEX PROFILE PHOTONIC CRYSTALS

Spatial beam compression of an electromagnetic wave is one of the fundamental techniques employed in microwaves and optics. As there are many ways to achieve this task using the combination of prisms and lenses, recent research suggests the parabolic gradient index photonic crystals (GRIN PC) for the design of spatial beam compressor owing to its functionalities. However, the fabrication of a graded media with the parabolic proflle is a di-cult challenge in practical realization. As an alternative, present work attempts this problem with respect to the triangular gradient index proflle. The performance and aspects of the beam compression are investigated experimentally using the pillar type GRIN PC at the microwave length-scales. The utility of the device for an efiective beam injection to the photonic-waveguide component is further demonstrated experimentally.

Long-term Effects of Peach Production Systems for Standard and Pillar Growth Types on Yield and Economic Parameters

The lack of dwarfing rootstocks for peach has led to cultural and genetic approaches that reduce tree size and vegetative growth to establish high-density plantings. The objectives of the study were to evaluate the interactions of pruning strategies, groundcover management, tree densities, and peach (Prunus persica) architecture combined in eight peach production systems on components of yield and economic value. The use of sod management reduced pruning time and costs, but the reduction of crop load reduced net return. High-density plantings in large vegetation-free areas (VFAs) had greater economic return than low-density plantings.

Development of sequence‐tagged site markers linked to the pillar growth type in peach (Prunus persica)

With 5 figures and 3 tablesAbstractIn peach [Prunus persica (L.) Batsch], trees showing columnar (also termed pillar or broomy) growth habit are of interest for high‐density production systems. While the selection of the pillar homozygous phenotype (brbr) can be carried out prior to field planting, the intermediate heterozygous upright phenotype is difficult to distinguish from standard trees until they are quite large in the field. Application of marker‐assisted selection would be helpful in establishing more efficient breeding programmes developing pillar and upright varieties. Thirty‐four amplified fragment length polymorphism (AFLP) markers and three simple sequence repeat (SSR) markers identified by bulked segregant analyses mapped together with the br gene on linkage group 2 (LG 2) of the Prunus reference map. The linkage group covers 92.9 cM. The AFLP marker ETGM61_291R mapped with 4.8 cM to the br gene on one side and the closest AFLP markers ETAM56_267A, ECAM61_426A and ETAM48_279A with 3.8 cM on the other side. These four AFLP markers were sequenced, and two, ETGM61_291R and ETAM48_279A, were successfully converted into sequence‐tagged site (STS) markers for marker‐assisted selection. BLAST searches against the peach genome placed the br gene in the region 17–18 Mb on LG 2.

Arthrodiastasis of the Hip

Hip distraction in Legg-Calvé-Perthes disease unloads the joint, which negates the harmful effect of the stresses on the articular surface, which may promote the sound healing of the areas of necrosis. Nonarticulated arthrodiastasis without soft tissue release using an Ilizarov external fixator was applied to 29 patients with Legg-Calvé-Perthes disease (older than 8 y at onset and lateral pillar type C or B). Follow-up period ranged from 2.5 to 11 years with an average of 7.5 years. Twenty-seven cases (93%) had improvement of the range of motion postoperatively. Preoperatively, all patients had constant pain, whereas at last follow-up 26 (86%) patients had no pain and 3 had an improvement. Stulberg classification was applied to 21 cases who reached skeletal maturity at last follow-up: 9 cases were type II, 7 cases were type III, 4 cases were type IV, and 1 case was type V. Nonarticulated hip distraction without soft tissue release seems to be a valid treatment option in cases with Legg-Calvé-Perthes disease where poor results are expected from conventional treatment.

A numerical study of broadband absorbers for visible to infrared detectors

We have studied the electromagnetic response of micro-structured surfaces realized with pillar arrays intended to provide a broadband (0.5–5.0 μm) absorption enhancement for HgCdTe photovoltaic detector arrays. We have considered both square and hexagonal lattice pillar configurations. Using a finite-difference time-domain approach we have found that the absorption enhancement is weakly dependent on the pillar lattice type, but the lattice period does have a significant impact on the enhancement. The use of these micro-structured surfaces makes it possible to eliminate the need for anti-reflection coatings on the detector back-side while maintaining negligible reflectance over a broad spectral band.

Is the Cassie−Baxter Formula Relevant?

The utility of the Cassie-Baxter formula to predict the apparent contact angle of a drop on rough hydrophobic surfaces has been questioned recently. To resolve this issue, experimental and numerical data for advancing and receding contact angles are reported. In all cases considered it is seen that contact angles follow the overall trend of the Cassie-Baxter formula, except for the advancing front on pillar type roughness. It is shown that deviations from the Cassie-Baxter angle have a one-to-one correlation with microscopic distortions of the contact line with respect to its configuration in the Cassie-Baxter state.

Analysis by simulation of amorphization current in phase change memory applied to pillar and GST confined type cells

In this work comparative simulations and analysis of amorphization current are presented for pillar type and GST confined type PCRAM structures. The simulations are realized with the PCM model of Sentaurus Device using an analytical phase transition model coupled with a drift–diffusion electro-thermal model for the transport. The objectives of this work are the selection of optimized cell structures for reset conditions. It is confirmed that regarding I reset the GST confined cell is more efficient than the pillar type. Our study points out that a compromise has to be found in some devices where the conditions of an optimized amorphous current correspond to a lowered resistivity contrast between the amorphous and crystalline states. A compromise has also to be found between optimal structures as designed by simulation and technological constraints associated to their fabrication.

(en)Mn2(V2O7): A 3D manganese vanadate built by Mn–O layers and two types of pillars of V2O7 and en bridges

Abstract An unexpected 3D manganese vanadate (en)Mn2(V2O7) (1) (en = ethylenediamine) has been hydrothermally obtained by H2E2Ge2O3 (E = − CH2CH2COO−) ligands and well-prepared mixture of V–Mn-amine and characterized by IR spectroscopy, elemental analysis, thermal stability and powder X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that the structure is a novel pillared-layer, in which MnO5N octahedra are corner-linked to form an infinite sheet with 4-membered rings (MRs) and further condensed to the 3D framework. The most prominent feature of 1 is the connection between the sheets via double bridges, namely, inorganic V2O7 dimeric units and organic en molecules. It is noteworthy that inorganic and organic double bridges between sheets have not been seen in manganese vanadates.

Evaluation of the effect of baffle shape in flocculation basin on hydrodynamic behavior using computational fluid dynamics

This study on the party wall of a flocculation basin provides important ground to facilitate the inducement of uniformity in the rectangular sedimentation basin and to achieve an improvement in sedimentation efficiency. In the water treatment plant used for this study, perforated baffle type, square type, pillar type and downward rectangular type partitions have been applied. We evaluated the hydrodynamic behavior of several types of party walls in the flocculation basin by using computational fluid dynamics (CFD). The perforated baffle type demonstrates more effective output for uniform flow than the square type, and the third party wall of the flocculation process has the most influence of the three party walls for water flow distribution. To prevent sinking of the flocs formed between the third party wall and the final outlet wall, it is necessary to develop the third party wall into an actual final outlet wall or to modify it into a pillar baffle type. In the case of a drinking water treatment system that treats low density water, a perforated baffle is more efficient as the final outlet wall because a downward rectangular type may form a bottom flow, which may cause a reduction in the efficiency of the volume capacity.

Thesis for Improvement in Pillar Type Signboards for City of Gimpo's Urban Environment

Thesis for Improvement in Pillar Type Signboards for City of Gimpo's Urban Environment

Versatile assembly of p-carboxylatocalix[4]arene-O-alkyl ethers

Crystallisation of lower-rim tetra-O-alkylated p-carboxylatocalix[4]arenes from pyridine results in the formation of both bi-layer and pillar type supramolecular motifs. Full alkylation at the calixarene lower rim has significant influence over the supramolecular self-assembly motif, including preclusion of pyridine guest molecules from the calixarene cavity in the solid state.