• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.5
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• pp.455-459
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• 2002

I have investigated the effects of annealing on a polymeric $\alpha-C_3N_{4.2}$ at high pressure and temperature in the presence of seeds of crystalline carbon nitride films prepared by a high voltage discharge plasma. The samples were evaluated by x-ray photoelectron spectroscopy (XPS), infrared spectroscopy, Auger electron spectroscopy and x-ray diffraction(XRD). Notably, XPS studies of the film composition before and after annealing demonstrate that the nitrogen composition in $\alpha-C_3N_{4.2}$ material initially containing more than 58% nitrogen decreases during the annealing process and reaches a common, stable composition of ~43%. XPS analysis also shows that the nitrogen composition in the annealed films without polymeric $\alpha-C_3N_{4.2}$ was reduced from 35% to 17%. Furthermore the concentration of the sp$^3$bonded phase increased with the increment of the annealing temperature.

• Transactions on Electrical and Electronic Materials
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• v.15 no.1
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• pp.16-19
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• 2014

Charge trapping nonvolatile memory capacitors with $ZrO_2$ as charge trapping layer were fabricated, and the effects of post annealing atmosphere ($NH_3$ and $N_2$) on their memory storage characteristics were investigated. It was found that the memory windows were improved, after annealing treatment. The memory capacitor after $NH_3$ annealing treatment exhibited the best electrical characteristics, with a 6.8 V memory window, a lower charge loss ~22.3% up to ten years, even at $150^{\circ}C$, and excellent endurance (1.5% memory window degradation). The results are attributed to deep level bulk charge traps, induced by using $NH_3$ annealing.

• The Korean Journal of Ceramics
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• v.1 no.1
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• pp.13-20
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• 1995

Effects of thermal annealing on the dielectric/piezoelectric properties of $Pb(Zn, Mg)_{1/3}Nb_{2/3}O_3-PbTiO_3$ ceramics (PZMNPT) with Zn/Mg=6/4) were examined across the rhombohedral/tetragonal morphotropic phase boundary (MPB). Both the relative dielectric permittivity ($\varepsilon$r)and the piezoelectric constant($d_33$)/electromechanical coupling constant ($k_p$)were increased by thermal annealing ($800^{\circ}$~$900^{\circ}C$) after sintering at $1150^{\circ}C$ for 1 hr. Based on the dielectric analysis using the series mixing model and the concept of a random distribution of the local Curie points, the observed improvements in the dielectric and piezoelectric properties of PZMN-PT were interpreted in terms of the elimination of PbO-rich amorphous intergranular layers(~1nm) induced by thermal annealing. A concrete evidence of the presence of amorphous grain-boundary layers in the unannealed (as-sintered) specimen was obtained by examining the structure of intergranular region using a TEM.

• Journal of the Korean Vacuum Society
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• v.14 no.3
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• pp.159-164
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• 2005

Indium tin oxide (ITO) films were deposited on a glass slide at a thickness of 280 nm by radio frequency(rf) magnetron sputtering from a ceramic target composed of $In_2O_3\;(90\%)\;+\;SnO_2\;(10\%)$. We investigated the effects of the annealing temperature (Ta) between 200 and 350'E for 30 min in air on such properties as thermal stability, surface morphology, and crystal structure of the films. X-ray diffraction spectra revealed that all the films were oriented preferably with [222] direction and [440] direction and the peak intensity increased with increasing annealing temperature. X-ray photoelectron spectroscopy (XPS) showed that the sodium was out-diffused from the glass substrate at the annealing temperature of $350^{\circ}C$. The sodium composition of the ITO film amlealed at $350^{\circ}C\;for\;30\;min\;was\;2.5\%$ at the surface. Also the sodium peak almost disappeared after 3 keV $Ar^+$sputtering for 6 min. The visible transmittance of all ITO films was over $77\%$.

• Journal of Magnetics
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• v.4 no.1
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• pp.5-9
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• 1999

Effect of sulfur segregation on tertiary recrystallization and magnetic induction during final annealing was investigated in a 3% Si-Fe electrical strip containing 6 ppm(LS) and 15 ppm(HS) sulfur. During final annealing, Auger peak height of segregated sulfur on the surface of the strips reached a maximum, and then decreased to low level with increasing annealing time, which is attributed to sulfur segregation and evaporation. The magnetic induction of the thin-gauged 3% Si strip was inversely proportional to the Auger peak height of segregated sulfur on the surface. The overall profile for surface segregation of sulfur and B10 was observed, irrespective of sulfur content in Si-Fe strips, but the peaks of LS strips appeared earlier than those of HS strips. The grain growth rate of the LS strips during final annealing was faster than that of the HS strips, which may be attributed to the pinning effects of segregated sulfur. With increasing final annealing temperature, B10 value increased rapidly and the saturation level in B10 increased.

• Macromolecular Research
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• v.11 no.1
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• pp.62-68
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• 2003

Thermotropic liquid crystalline polymer (TLCP)/poly(ethylene 2,6-naphthalate) (PEN)/poly(ethylene terephthalate) (PET) ternary blends were prepared by melt blending, and were melt-spun to fibers at various spinning speeds in an effort to improve fiber performance and processability. Structure and property relationship of TLCP/PEN/PET ternary blend fibers and effects of annealing on those were investigated. The mechanical properties of ternary blend fibers could be significantly improved by annealing, which were attributed to the development of more ordered crystallites and the formation of more perfect crystalline structures. TLCP/PEN/PET ternary blend fibers that annealed at 18$0^{\circ}C$ for 2 h, exhibited the highest values of tensile strength and modulus. The double melting behaviors observed in the annealed ternary blend fibers depended on annealing temperature and time, which might be caused by different lamellae thickness distribution as a result of the melting-reorganization process during the DSC scans.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.431-436
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• 2002

To develop a method for increasing RS level in maize starch, cross-linked resistant starches treated with annealing were prepared. Maize starch and amylomaize VII were used in the study and annealed at $40{\sim}60^{\circ}C$ before cross-linking modification. To compare effect of annealing below gelatinization temperature, starches were heat treated at 70 and $100^{\circ}C$. RS contents were assayed by pancreatin-gravimetric (P/G) method. When maize starch and amylomaize VII were cross-linked at $45^{\circ}C$ and pH 11.0 by slurrying the starch on a solution of STMP(sodium trimetaphosphate), STPP(sodium tripolyphosphate), and sodium sulfate, RS content was 14.7% and 45.3%, respectively. Annealing below gelatinization temperature before cross-linking increased RS contents of prepared cross-linked starches but did not affect the swelling power. Heat treatment above gelatinization temperature increased the swelling power of cross-linked starch prepared from maize starch. The characteristics by X-ray diffractometry and scanning electron microscopy of cross-linked resistant starch were not changed by annealing.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.127-130
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• 2011

We investigated the effects of $O_2$ annealing (i.e., temperature and time) on the characteristics of hafnium silicate ($HfSi_xO_y$) films deposited on a Si substrate by atomic layer deposition process (ALD). We found that the post deposition annealing under oxidizing ambient causes the oxidation of residual Hf metal components, resulting in the improvement of electrical characteristics (e.g., hysteresis window and leakage current are decreased). In addition, we observed the annealing temperature is more important than the annealing time for post deposition annealing. Based on these observations, we suggest that post deposition annealing under oxidizing ambient is necessary to improve the electrical characteristics of $HfSi_xO_y$ films deposited by ALD. However, the annealing temperature has to be carefully controlled to minimize the regrowth of interfacial oxide, which degrades the value of equivalent oxide thickness.

• Fashion & Textile Research Journal
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• v.15 no.6
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• pp.985-992
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• 2013

Polytrimethylene terephthalate(PTT) offers several advantageous properties such as good tensile strength, uniformity, stiffness, toughness, UV stability, resilience, stain resistance, outstanding elastic recovery, and dyeability. The effects of annealing temperature on physical properties and the structure of PTT filaments and yarn were investigated by measuring wide-angle X-ray diffraction (WAXD), density, optical birefringence, dynamic visco elasticity, and tensile testing. The intensity of maximum tan ${\delta}$ decreased and the temperature of maximum tan ${\delta}$ shifted to a higher temperature as the annealing temperature of filaments increased; however, it shifted to a lower temperature when the annealing temperature exceeded $130^{\circ}C$. In addition, crystallinity, density and D-spacing of (010) crystal face increased as the annealing temperature increased. Optical birefringence and specific stress were almost constant up to $100^{\circ}C$ and then decreased above $130^{\circ}C$. The shrinkage of PTT filament is 0 in boiling water when annealed above $130^{\circ}C$; consequently, the use of annealed fiber above $130^{\circ}C$ can remove thermal instability when dyeing PTT fiber. In the case of yarns, the thermal stability and physical properties of yarns showed the best effect when the ply number is less than 5, twist number is less than 400tpm, and the annealing time is 20minutes.

• Journal of Magnetics
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• v.15 no.4
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• pp.179-184
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• 2010

We have investigated the effects of post annealing on iron oxide nanoparticles synthesized by the novel hydrothermal synthesis method with the $FeSO_4{\cdot}7H_2O$. To investigate the post annealing effect, the as-synthesized iron oxide nanoparticles were annealed at different temperatures in a vacuum chamber. The morphological, structural and magnetic properties of the iron oxide nanoparticles were investigated with high resolution X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Mossbauer spectroscopy, and vibrating sample magnetometer analysis. According to the XRD and HRTEM analysis results, as-synthesized iron oxide nanoparticles were only magnetite ($Fe_3O_4$) phase with face-centered cubic structure but post annealed iron oxide nanoparticles at $700^{\circ}C$ were mainly magnetite phase with trivial maghemite ($\gamma-Fe_2O_3$) phase which was induced in the post annealing treatment. The crystallinity of the iron oxide nanoparticles is enhanced by the post annealing treatment. The particle size of the as-synthesized iron oxide nanoparticles was about 5 nm and the particle shape was almost spherical. But the particle size of the post annealed iron oxide nanoparticles at $700^{\circ}C$ was around 25 nm and the particle shape was spherical and irregular. The as-synthesized iron oxide nanoparticles showed superparamagnetic behavior, but post annealed iron oxide nanoparticles at $700^{\circ}C$ did not show superparamagnetic behavior due to the increase of particle size by post annealing treatment. The saturation of magnetization of the as-synthesized nanoparticles, post annealed nanoparticles at $500^{\circ}C$, and post annealed nanoparticles at $700^{\circ}C$ was found to be 3.7 emu/g, 6.1 emu/g, and 7.5 emu/g, respectively. The much smaller saturation magnetization value than one of bulk magnetite can be attributed to spin disorder and/or spin canting, spin pinning at the nanoparticle surface.