Chemical surface densification of hardwood through lateral monomer impregnation and in situ electron beam polymerization, Part I: density profile and surface hardness of three hardwood species

Poplar (Populus tomentosa Carr.) solid wood was surface densified in the tangential direction, and the vertical density profile (VDP) and hardness of the treated and untreated samples were measured. The effects of the process parameters on the VDP and hardness were investigated. To explicitly describe the VDP of the surface densified wood, five indices (AD, ADx, PD, PDi, and DTh) were used. The compressing temperature and closing speed influenced the formation and shape of the VDP. A higher temperature yielded a greater PD and Pdi, and a faster closing speed yielded a higher PD, but smaller PDi and DTh. Increasing the compression ratio increased the AD, ADx, and maximum load, and the poplar wood was compressed in the overall thickness as the compression ratio exceeded a certain degree. The Janka hardness of the poplar wood was significantly improved after surface densification; a higher temperature resulting in a higher surface hardness was explained by the higher PD. The closing speed and compression ratio affected the hardness by impacting the VDP, specifically the PD and DTh indices. When the PD and DTh were greater the surface hardness was greater. By this study, a compressing temperature of 140 to 160 °C and the closing speed of 10 mm/min is recommended, and to prevent the deformation of unheated side of the wood samples and obtain a higher surface hardness, the compression ratio is restricted to 20%.

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Nucleation and Early Growth of Sputtered thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069570 ◽

1970 ◽

Vol 28 ◽

pp. 516-517

Author(s):

Dudley M. Sherman ◽

Thos. E. Hutchinson

Keyword(s):

Thin Films ◽

Electron Beam ◽

Ion Beam ◽

Ion Source ◽

Water Cooling ◽

Stages Of Growth ◽

Lens Assembly ◽

Microscope Technique ◽

Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

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A very rapid in situ Kikuchi technique to determine relative crystal misorientation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106211 ◽

1988 ◽

Vol 46 ◽

pp. 830-831

Author(s):

J. I. Bennetch

Keyword(s):

Electron Beam ◽

Analytical Techniques ◽

Superplastic Forming ◽

The Other ◽

Kikuchi Pattern ◽

Kikuchi Line ◽

Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

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In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137653 ◽

1995 ◽

Vol 53 ◽

pp. 256-257

Author(s):

J. Drucker ◽

R. Sharma ◽

J. Kouvetakis ◽

K.H.J. Weiss

Keyword(s):

Electron Beam ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Quantum Effect ◽

Line Drawing ◽

Chemical Vapor ◽

Environmental Cell ◽

Engineering Changes ◽

Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

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In-Situ Dual Beam (FIBSEM) Techniques for Probe Pad Deposition and Dielectric Integrity Inspection in 0.2 μm Technology DRAM Single Cells

ISTFA 1999: Conference Proceedings from the 25th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1999p0311 ◽

1999 ◽

Author(s):

Gunnar Zimmermann ◽

Richard Chapman

Keyword(s):

Electron Beam ◽

Single Cell ◽

Single Cells ◽

Ion Beam ◽

Gate Oxide ◽

Ion Milling ◽

Dual Beam ◽

Sem Imaging ◽

Innovative Techniques

Abstract Dual beam FIBSEM systems invite the use of innovative techniques to localize IC fails both electrically and physically. For electrical localization, we present a quick and reliable in-situ FIBSEM technique to deposit probe pads with very low parasitic leakage (Ipara < 4E-11A at 3V). The probe pads were Pt, deposited with ion beam assistance, on top of highly insulating SiOx, deposited with electron beam assistance. The buried plate (n-Band), p-well, wordline and bitline of a failing and a good 0.2 μm technology DRAM single cell were contacted. Both cells shared the same wordline for direct comparison of cell characteristics. Through this technique we electrically isolated the fail to a single cell by detecting leakage between the polysilicon wordline gate and the cell diffusion. For physical localization, we present a completely in-situ FIBSEM technique that combines ion milling, XeF2 staining and SEM imaging. With this technique, the electrically isolated fail was found to be a hole in the gate oxide at the bad cell.

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In Situ Study of Vacancy Disordering in Crystalline Phase-Change Materials Under Electron Beam Irradiation

SSRN Electronic Journal ◽

10.2139/ssrn.3485063 ◽

2019 ◽

Author(s):

Ting-Ting Jiang ◽

Xu-Dong Wang ◽

Jiang-Jing Wang ◽

Yu-Xing Zhou ◽

Dan-Li Zhang ◽

...

Keyword(s):

Electron Beam ◽

Phase Change ◽

Crystalline Phase ◽

Electron Beam Irradiation ◽

Phase Change Materials ◽

Beam Irradiation ◽

In Situ Study

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In situ TEM observation of novel chemical evolution of MnBr2 catalyzed by Cu under electron beam irradiation

Chemical Physics Letters ◽

10.1016/j.cplett.2017.08.007 ◽

2017 ◽

Vol 686 ◽

pp. 44-48 ◽

Cited By ~ 1

Author(s):

Wei Wang ◽

Xianwei Bai ◽

Xiangxiang Guan ◽

Xi Shen ◽

Yuan Yao ◽

...

Keyword(s):

Electron Beam ◽

Chemical Evolution ◽

Electron Beam Irradiation ◽

In Situ Tem ◽

Beam Irradiation

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In Situ Observation of Electron-Beam-Induced Formation of Nano-Structures in PbTe

Nanomaterials ◽

10.3390/nano11010163 ◽

2021 ◽

Vol 11 (1) ◽

pp. 163

Author(s):

Iryna Zelenina ◽

Igor Veremchuk ◽

Yuri Grin ◽

Paul Simon

Keyword(s):

Electron Beam ◽

Gas Phase ◽

Threshold Current ◽

Threshold Current Density ◽

Atomic Scale ◽

In Situ Observation ◽

Nano Structures ◽

Transmission Electron ◽

Initial Crystal

Nano-scaled thermoelectric materials attract significant interest due to their improved physical properties as compared to bulk materials. Well-shaped nanoparticles such as nano-bars and nano-cubes were observed in the known thermoelectric material PbTe. Their extended two-dimensional nano-layer arrangements form directly in situ through electron-beam treatment in the transmission electron microscope. The experiments show the atomistic depletion mechanism of the initial crystal and the recrystallization of PbTe nanoparticles out of the microparticles due to the local atomic-scale transport via the gas phase beyond a threshold current density of the beam.

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