• 한국재료학회지
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• 제12권5호
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• pp.375-381
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• 2002

N-type ${\beta}-FeSi_2$ with a nominal composition of $Fe_{0.98}Co_{0.02}Si_2$ powders has been produced by mechanical alloying process and consolidated by vacuum hot pressing. As-milled powders were of metastable state and fully transformed to ${\beta}-FeSi_2$ phase by subsequent isothermal annealing. However, as-consolidated $Fe_{0.98}Co_{0.02}Si_2$ consisted of untransformed mixture of ${\alpha}-Fe_2Si_ 5$ and $\varepsilon$-FeSi phases. Isothermal annealing has been carried out to induce the transformation to a thermoelectric semiconducting ${\beta}-FeSi_2$ phase. The transformation behavior of ${\beta}-FeSi_2$ was investigated by utilizing DTA, a modified TGA under magnetic field, SEM, and XRD analyses. Isothermal annealing at $830^{\circ}C$ in vacuum led to the thermoelectric semiconducting ${\beta}-FeSi_2$ phase transformation, but some residual metallic $\alpha$ and $\varepsilon$ phases were unavoidable even after prolonged annealing. Thermoelectric properties were remarkably improved by isothermal annealing due to the transformation from metallic $\alpha$ and $\varepsilon$ phases to semiconducting phases.

• Journal of Advanced Marine Engineering and Technology
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• 제39권1호
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• pp.81-85
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• 2015

본 연구에서는 Poly (3-hexylthiophene-2,5-diyl) (P3HT):[6,6]-Phenyl C61 butyric acid methyl ester (PCBM)과 GaN를 이용하여 유무기 하이브리드 광전변환소자를 제작함에 있어서, P3HT:PCBM 활성층의 열처리가 소자의 단락전류밀도에 미치는 영향을 알아보았으며 이때 유기물의 농도와 혼합비율을 달리 하였다. 유기물 각각의 층을 코팅하여 층을 만들 때마다 열처리 한 경우, 즉 pre-annealing샘플과 pre-annealing 과정을 거쳐 제작된 소자 전체를 한 번 더 열처리하여 즉 post-annealing까지 행한 샘플을 비교하였다. 그 결과 post-annealing한 샘플이 더 높은 단락전류밀도의 값을 가졌고 이때 P3HT와 PCBM은 1wt%와 1:1 혼합비율에서 좋은 열처리 효과를 나타내었다.

• 한국표면공학회지
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• 제25권6호
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• pp.293-298
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• 1992

Various vanadium-oxide thin films were deposited by e-beam and thermal evaporation of V2O5, V2O3, and VO2 powders. Films with thickness of $2000\AA$ were subjected to annealing at $300^{\circ}C$~$450^{\circ}C$ in N2 atmosphere for the crystallization and desification purposes. For the films deposited from V2O5 and VO2 sources, sources, Magneli (VnO2n-1$ 4\leq$ $n\leq$ 8) and VO2 phase appeared at $300^{\circ}C$, respectively, but VO2 phase also transformed into Magneli phase at $450^{\circ}C$ by severe reduction. On the contrary, VO2/VO mixed phases resulted from congruent evaporation of V2O3 unchanged after the same annealing treatment due to the balanced reduction and oxidation of VO2 and VO whcih have different equilibrium O2 pressures. It is suggested that the annealing in the controlled oxidation atmosphere or the deposition using mixed oxide sources are necessary to get the film containing VO2 phase.

• 한국전기전자재료학회논문지
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• 제14권12호
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• pp.965-971
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• 2001

$\beta$-Ga$_2$O$_3$ nanobelts and nanoparticles were synthesized from mechanically ground GaN powders with thermal annealing in a nitrogen atmosphere and an oxygen atmosphere, respectively. The study of field emission scanning electron microscopy (FESEM) on the microstructures of nanomaterials revealed that the nanobelts synthesized in the nitrogen atmosphere are with the range of 20~1000nm width and 10 ~100nm thickness, and that nanomaterials are nanoparticles with 20~50nm radius obtained by thermal annealing in an oxygen atmosphere. The crystal structure of the $\beta$-Ga$_2$O$_3$ nanobelts and nanoparticles was in this study investigated by X-ray diffractometer (XRD) and high-resolution transmission electron microscope (HRTEM). The formation processes of the nanobelts and nanoparticles will be discussed in this paper.

• 한국분말재료학회지
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• 제22권4호
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• pp.278-282
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• 2015

The GaN-powder scrap generated in the manufacturing process of LED contains significant amounts of gallium. This waste can be an important resource for gallium through recycling of scraps. In the present study, the influence of annealing temperatures on the structural properties of GaN powder was investigated when the waste was recycled through the mechanochemical oxidation process. The annealing temperature varied from $200^{\circ}C$ to $1100^{\circ}C$ and the changes in crystal structure and microstructure were studied. The annealed powder was characterized using various analytical tools such as TGA, XRD, SEM, and XRF. The results indicate that GaN structure was fully changed to $Ga_2O_3$ structure when annealed above $900^{\circ}C$ for 2 h. And, as the annealing temperature increased, crystallinity and particle size were enhanced. The increase in particle size of gallium oxide was possibly promoted by powder-sintering which merged particles to larger than 50 nm.

• The Korean Journal of Ceramics
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• 제3권4호
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• pp.274-278
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• 1997

(Ba, Sr) TiO$_3$(BST) thin films were prepared on RuO$_2$/Si substrates by rf magnetron sputtering and annealing was followed at temperatures ranging from 550 to 80$0^{\circ}C$ in $N_2$or $O_2$atmosphere. The effects of annealing conditions on the properties of BST film deposited on RuO$_2$bottom electrodes were investigated. It was found that the crystallinity. surface roughness, and grain size of BST films vary with the annealing temperature but they are not dependent upon the annealing atmosphere. The flat region in the current-voltage (I-V) curves of BST capacitors shortened with increasing annealing temperature under both atmospheres. This is believed to be due to the lowering of potential barrier caused by unstable interface and the increase of charge The shortening of the flat region by $O_2$annealing was more severe than that by $N_2$-annealing. As a result, there was no flat region when the films were annealed at 700 and 80$0^{\circ}C$ in $O_2$atmosphere. The dielectric properties of BST films were improved by annealing in either atmosphere. however, a degradation with frequency was observed when the films were annealed at relatively high temperature under $O_2$atmosphere.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.103-107
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• 2000

Boron Phosphide films were deposited on the glass substrate at the low temperature, 55$0^{\circ}C$, by the reaction of B$_2$H$_{6}$ with PH$_3$ using CVD. $N_2$ was employed as carrier gas. The optimal gas rates were 50 $m\ell$/min for B$_2$H$_{6}$, 50 $m\ell$/min for PH$_3$ $m\ell$/min and 1.5 $\ell$/min for $N_2$. To investigate the annealing effect, the films were annealed for 1hour, 3hours in $N_2$ambient at 55$0^{\circ}C$ and tested. The deposition rate was 1000$\AA$/min and the refractive index of film was 2.6. The measurement of X-RD shows that the films have the preferred orientation of (1 0 1) and the intensity of the peak for (1 0 1) orientation decreases according to the annealing time. The data of VIS spectrophotometer proved that the films are transparent in the visible range and the maximal transmittance increases according to the annealing time; 75.49% for as-deposited, 76.71% for 1hr-annealed and 86.4 % for 3hrs-annealed. The measurement of AFM shows that the average surface roughness increases according to the annealing time; 73$\AA$ for as-deposited, 88.9$\AA$ for 1hr-annealed and 220$\AA$ for 3hrs-annealed. Also, The data of the secondary electron emission rate(Υ) shows that the secondary electron emission rate increases according to the annealing time; 0.317 for 1hr-deposited, 0.357 for 1hr-annealed and 0.537 for 3hrs-annealed. And, The measurement of FT-IR that the characteristic of transmittance in the infrared range was stabilized through annealing.ing.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.128-129
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• 2008

The annealing effects of $SiO_2/Si_3N_4$ stacked tunneling dielectrics were investigated. I-V characteristics of band gap engineered tunneling gate stacks consisted of $Si_3N_4/SiO_2/Si_3N_4$(NON), $SiO_2/Si_3N_4/SiO_2$(ONO) dielectrics were evaluated and compared with $SiO_2$ single layer using the MOS(Metal-Oxide-Semiconductor) capacitor structure. The leakage currents of engineered tunneling barriers (ONO, NON stacks) are lower than that of the conventional $SiO_2$ single layer at low electrical field. Meanwhile, the engineered tunneling barriers have larger tunneling current at high electrical field and improved electrical characteristics by annealing processes than $SiO_2$ layer.

• 전기전자학회논문지
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• 제23권2호
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• pp.704-709
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• 2019

본 논문에서는 다양한 열처리(annealing) 조건에서 tunneling field effect transistor(TFET)의 전기적 특성을 연구 하였다. TFET 샘플은 수소 혼합 가스(4 %) 및 중수소($D_2$) 혼합 가스 (4 %)를 사용하여 열처리를 진행하였으며 측정은 노이즈 차폐실에서 진행되었다. 실험 결과, 열처리 전과 비교하여 열처리 공정 후에 subthreshold slope(SS)이 33 mV / dec만큼 감소함을 확인할 수 있었다. 그리고 측정 온도 범위에서 온도가 증가할수록 $V_G=3V$ 조건에서 10 기압의 중수소 혼합 가스에 대해 평균 31.2 %의 노이즈가 개선됨을 확인할 수 있었다. $D_2$ 혼합 가스로 메탈 증착 후 열처리 공정(post metal annealing)을 실시한 결과, $I_D=100nA$ 조건에서 평균 30.7 %의 노이즈가 감소되었음을 확인할 수 있다.

• 전자공학회논문지D
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• 제35D권7호
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• pp.94-101
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• 1998

To form 0.2 .mu.m p$^{+}$-n junctions, BF$_{2}$ ions with the energy of 20keV and the dose of 2*10$^{15}$ cm$^{-2}$ were implanted into the crystalline and preamorphized silicon substrates. Th epreamorphization was performed using 45keV, 3*10$^{14}$ cm$^{-2}$ As or Ge ions. Th efurnace annealing and rapid thermal annealing were empolyed to annihilate the implanted damage and to activate the implanted boron ions.The junction properties were analyzed with the measured values of the junction depth, sheet resistances, residual defects, and leakage currents. The thermal cycle of furnace annela followed by rapid thermal annela shows better characteristics than the annealing sequence of rapid thermal anneal and furnace annela.Among the premorphization species, Ge ion exhibited the better characteristics than the As ion.n.