Fabrication of asymmetric-gradient-concentric ring patterns via evaporation of droplets of PMMA solution at different substrate temperatures

Asymmetric-gradient-concentric ring patterns are fabricated via evaporating a PMMA solution droplet with a circular copper ring as template. Various micro-patterns are formed in the trench between the polymer rings.

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(111) Monocrystalline Nickel Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095819 ◽

1972 ◽

Vol 30 ◽

pp. 512-513

Author(s):

T.E. Pratt ◽

R.W. Vook

Keyword(s):

Film Thickness ◽

Deposition Rate ◽

Room Temperature ◽

Narrow Range ◽

High Vacuum ◽

Residual Pressure ◽

Temperature Dependent ◽

Deposition Parameters ◽

Transmission Electron ◽

Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

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Observations on the growth of barium bismuth oxide thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120783 ◽

1992 ◽

Vol 50 (1) ◽

pp. 76-77

Author(s):

M G. Norton ◽

E.S. Hellman ◽

E.H. Hartford ◽

C.B. Carter

Keyword(s):

Substrate Temperature ◽

Deposition Process ◽

Nucleation Layer ◽

Second Stage ◽

Device Applications ◽

High Transition ◽

Substrate Temperatures ◽

Oriented Material ◽

Barium Bismuth ◽

Superconductor Device

The bismuthates (for example, Ba1-xKxBiO3) represent a class of high transition temperature superconductors. The lack of anisotropy and the long coherence length of the bismuthates makes them technologically interesting for superconductor device applications. To obtain (100) oriented Ba1-xKxBiO3 films on (100) oriented MgO, a two-stage deposition process is utilized. In the first stage the films are nucleated at higher substrate temperatures, without the potassium. This process appears to facilitate the formation of the perovskite (100) orientation on (100) MgO. This nucleation layer is typically between 10 and 50 nm thick. In the second stage, the substrate temperature is reduced and the Ba1-xKxBiO3 is grown. Continued growth of (100) oriented material is possible at the lower substrate temperature.

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TEM Study of Co/Pd and Co/Au Multilayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151015 ◽

1993 ◽

Vol 51 ◽

pp. 1036-1037

Author(s):

A.E.M. De Veirman ◽

F.J.G. Hakkens ◽

W.M.J. Coene ◽

F.J.A. den Broeder

Keyword(s):

Magnetic Anisotropy ◽

Ion Beam ◽

Perpendicular Magnetic Anisotropy ◽

Optical Recording ◽

Magnetic Multilayer ◽

Ion Beam Sputtering ◽

Cross Sectional ◽

Transmission Electron ◽

Beam Sputtering ◽

Substrate Temperatures

There is currently great interest in magnetic multilayer (ML) thin films (see e.g.), because they display some interesting magnetic properties. Co/Pd and Co/Au ML systems exhibit perpendicular magnetic anisotropy below certain Co layer thicknesses, which makes them candidates for applications in the field of magneto-optical recording. It has been found that the magnetic anisotropy of a particular system strongly depends on the preparation method (vapour deposition, sputtering, ion beam sputtering) as well as on the substrate, underlayer and deposition temperature. In order to get a better understanding of the correlation between microstructure and properties a thorough cross-sectional transmission electron microscopy (XTEM) study of vapour deposited Co/Pd and Co/Au (111) MLs was undertaken (for more detailed results see ref.).The Co/Pd films (with fixed Pd thickness of 2.2 nm) were deposited on mica substrates at substrate temperatures Ts of 20°C and 200°C, after prior deposition of a 100 nm Pd underlayer at 450°C.

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Microstructure of YBa2Cu3O7-x thin films deposited by dc sputtering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152835 ◽

1989 ◽

Vol 47 ◽

pp. 172-173

Author(s):

O. Eibl ◽

G. Gieres ◽

H. Behner

Keyword(s):

Thin Films ◽

Cross Sections ◽

Intermediate Layer ◽

Amorphous State ◽

Critical Currents ◽

Dc Sputtering ◽

State Process ◽

Diffraction Patterns ◽

Film Substrate ◽

Substrate Temperatures

The microstructure of high-Tc YBa2Cu3O7-X thin films deposited by DC-sputtering on SrTiO3 substrates was analysed by TEM. Films were either (i) deposited in the amorphous state at substrate temperatures < 450°C and crystallised by a heat treatment at 900°C (process 1) or (ii) deposited at around 740°C in the crystalline state (process 2). Cross sections were prepared for TEM analyses and are especially useful for studying film substrate interdiffusion (fig.1). Films deposited in process 1 were polycristalline and the grain size was approximately 200 nm. Films were porous and the size of voids was approximately 100 nm. Between the SrTiO3 substrate and the YBa2Cu3Ox film a densly grown crystalline intermediate layer approximately 150 nm thick covered the SrTiO3 substrate. EDX microanalyses showed that the layer consisted of Sr, Ba and Ti, however, did not contain Y and Cu. Crystallites of the layer were carefully tilted in the microscope and diffraction patterns were obtained in five different poles for every crystallite. These patterns were consistent with the phase (Ba1-XSrx)2TiO4. The intermediate layer was most likely formed during the annealing at 900°C. Its formation can be understood as a diffusion of Ba from the amorphously deposited film into the substrate and diffusion of Sr from the substrate into the film. Between the intermediate layer and the surface of the film the film consisted of YBa2Cu3O7-x grains. Films prepared in process 1 had Tc(R=0) close to 90 K, however, critical currents were as low as jc = 104A/cm2 at 77 K.

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Fabrication of 3D Micro Patterns on Concave Substrate and Its Application for the Fabrication of Cylindrical Polymer Stamps

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.132.303 ◽

2012 ◽

Vol 132 (9) ◽

pp. 303-308

Author(s):

Jongho Park ◽

Nobuyuki Takama ◽

Hiroyuki Fujita ◽

Beomjoon Kim

Keyword(s):

Micro Patterns

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Synthesis of Diamond in High Power-Density Microwave Methane/Hydrogen/Oxygen Plasmas at Elevated Substrate Temperatures

10.21236/ada362769 ◽

1999 ◽

Author(s):

Tsan-Heui Chein ◽

Jin Wei ◽

Yonhua Tzeng

Keyword(s):

Power Density ◽

High Power ◽

High Power Density ◽

Substrate Temperatures

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WATER DROPLET EVAPORATION IN A CHAMBER ISOLATED FROM THE EXTERNAL ENVIRONMENT

Tyumen State University Herald Physical and Mathematical Modeling Oil Gas Energy ◽

10.21684/2411-7978-2020-6-3-8-22 ◽

2020 ◽

Vol 6 (3) ◽

pp. 8-22

Author(s):

KSENIA A. Batishcheva ◽

ATLANT E. Nurpeiis

Keyword(s):

Water Vapor ◽

Evaporation Rate ◽

External Environment ◽

Heat Removal ◽

Droplet Evaporation ◽

Droplet Volume ◽

Evaporation Time ◽

Aluminum Alloy Amg6 ◽

Evaporation Of Droplets ◽

Contact Diameter

With an increase in the productivity of power equipment and the miniaturization of its components, the use of traditional thermal management systems becomes insufficient. There is a need to develop drip heat removal systems, based on phase transition effects. Cooling with small volumes of liquids is a promising technology for microfluidic devices or evaporation chambers, which are self-regulating systems isolated from the external environment. However, the heat removal during evaporation of droplets into a limited volume is a difficult task due to the temperature difference in the cooling device and the concentration of water vapor that is unsteady in time depending on the mass of the evaporated liquid. This paper presents the results of an experimental study of the distilled water microdrops’ (5-25 μl) evaporation on an aluminum alloy AMg6 with the temperatures of 298-353 K in an isolated chamber (70 × 70 × 30 mm3) in the presence of heat supply to its lower part. Based on the analysis of shadow images, the changes in the geometric dimensions of evaporating drops were established. They included the increase in the contact diameter, engagement of the contact line due to nano roughening and chemical composition inhomogeneous on the surface (90-95% of the total evaporation time) of the alloy and a decrease in the contact diameter. The surface temperature and droplet volume did not affect the sequence of changes in the geometric dimensions of the droplets. It was found that the droplet volume has a significant effect on the evaporation time at relatively low substrate temperatures. The results of the analysis of droplet evaporation rates and hygrometer readings have shown that reservoirs with salt solutions can be used in isolated chambers to control the concentration of water vapor. The water droplets evaporation time was determined. The analysis of the time dependences of the evaporation rate has revealed that upon the evaporation of droplets in an isolated chamber under the conditions of the present experiment, the air was not saturated with water vapor. The latter did not affect the evaporation rate.

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