• Title/Summary/Keyword: annealing heating rate

Search Result 35, Processing Time 0.023 seconds

Fabrication of Micro-Flow Sensors with High-response Time (고속응답 마이크로 유량센서의 제작)

  • Chung, Gwiy-Sang;Hong, Seok-Woo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.05b
    • /
    • pp.17-20
    • /
    • 2000
  • This paper describes on the fabrication and characteristics of hot-film type micro-flowsensors integrated with Pt-RTD's and micro-heaters on the Si substrate, in which MgO thin-films were used as medium layer in order to improve adhesion of Pt thin-films to $SiO_2$ layer, The MgO layer improved adhesion of Pt thin-films to $SiO_2$ layer without any chemical reactions to Pt thin-films under high annealing temperatures. In investigating output characteristics of the fabricated micro-flowsensors, the output voltages increased as gas flow rate and its conductivity increased due to increase of heat-loss from sensor to external. Output voltage was 82 mV at $N_2$ flow rate of 2000 seem/min, heating power of 1.2W.

  • PDF

Single Crystals Growth of Cubic Zirconia by Skull Method (Skull법에 의한 Cubic Zirconia 단결정 성장)

  • 김석호;최종건;오근호;조영환;김영준;오봉인;강원호
    • Journal of the Korean Ceramic Society
    • /
    • v.25 no.2
    • /
    • pp.161-167
    • /
    • 1988
  • Yttria-Stabilized Cubic Zirconia Crystals with Various Y2O3 amounts (6-15mol%) were grown by the Skull melting technique. The modeling of the nucleation at the Skull bottom and the best growth condition were studied. The abrupt changes in generator heating Power and lowering rate of crucible caused the dendritic growth in the grown crystal. The optimum condition of cubic Zirconia single crystals was obtained when the lowering rate was gradually increased. The effect of Y2O3 amounts on the perfection adn the color of the grown crystal were determined. The darkish color generated in the crystals added Y2O3 amounts over 12mol% was eliminated by the annealing in air at 1200$^{\circ}C$ for 24hrs.

  • PDF

플라즈마 도핑 후 급속열처리법을 이용한 n+/p 얕은 접합 형성

  • Do, Seung-U;Seo, Yeong-Ho;Lee, Jae-Seong;Lee, Yong-Hyeon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.11a
    • /
    • pp.50-50
    • /
    • 2009
  • In this paper, the plasma doping is performed on p-type wafers using $PH_3$ gas(10 %) diluted with He gas(90 %). The wafer is placed in the plasma generated with 200 W and a negative DC bias (1 kV) is applied to the substrate for 60 sec under no substrate heating. the flow rate of the diluted $PH_3$ gas and the process pressure are 100 sccm and 10 mTorr, respectively. In order to diffuse and activate the dopant, annealing process such as rapid thermal annealing (RTA) is performed. RTA process is performed either in $N_2$, $O_2$ or $O_2+N_2$ ambient at $900{\sim}950^{\circ}C$ for 10 sec. The sheet resistance is measured using four point probe. The shallow n+/p doping profiles are investigated using secondary ion mass spectromtry (SIMS). The analysis of crystalline defect is also done using transmission electron microscopy (TEM) and double crystal X-ray diffraction (DXRD).

  • PDF

The characterization for the Ti-silicide of $N^+P$ junction by 2 step RTD (2단계 RTD방법에 의한 $N^+P$ 접합 티타늄 실리사이드 특성연구)

  • 최도영;윤석범;오환술
    • Electrical & Electronic Materials
    • /
    • v.8 no.6
    • /
    • pp.737-743
    • /
    • 1995
  • Two step RTD(Rapid Thermal Diffussion) of P into silicon wafer using tungsten halogen lamp was used to fabricated very shallow n$^{+}$p junction. 1st RTD was performed in the temperature range of 800.deg. C for 60 see and the heating rate was in the 50.deg. C/sec. Phosphrous solid source was transfered on the silicon surface. 2nd RTD process was performed in the temperature range 1050.deg. C, 10sec. Using 2 step RTD we can obtain a shallow junction 0.13.mu.m in depth. After RTD, the Ti-silicide process was performed by the two step RTA(Rapid Thermal Annealing) to reduced the electric resistance and to improve the n$^{+}$p junction diode. The titanium thickness was 300.angs.. The condition of lst RTA process was 600.deg. C of 30sec and that of 2nd RTA process was varied in the range 700.deg. C, 750.deg. C, 800.deg. C for 10sec-60sec. After 2 step RTA, sheet resistance was 46.ohm../[]. Ti-silicide n+p junction diode was fabricated and I-V characteristics were measured.red.

  • PDF

The Changes of the Microstructure and the Physical Properties of Heat Set PET Partially Oriented Yarns (PET부분배향사(POY)의 열처리에 따른 내부구조 및 물성변화)

  • Choi Jong Myoung;Cho Gil Soo
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.12 no.3 s.28
    • /
    • pp.343-350
    • /
    • 1988
  • This study was carried out to investigate the microstructure and physical property of PET POY which was taut-annealed under various conditions. The DSC melting curves of annealed PET POY showed double melting peaks in most cases. As temperature and time increased, form II crystal became sharp and increased in size, and form I crystal decreased in size. The slower the heating rate, the higher the programmed heating effect during DSC analysis. Crystallinity and briefringence of annealed specimens increased as the treatment temperature and time increased. Breaking tenacity of specimens treated for 3 minutes increased as the treatment temperature increased, but others decreased. Elongation at break decreased as the annealing temperature and time increased. Dye uptake of annealed specimens decreased as the temperature increased up to $190^{\circ}C\~210^{\circ}C$. then the uptakes increased at higher temperatures. At the same temperature, dye uptake of the specimen decreased as time increased.

  • PDF

Effect of Milling Medium Materials on Mechanical Alloying of Mo-25.0at%Si Powder Mixture (Mo-25.0at%Si 혼합분말의 기계적 합금화에 미치는 밀링매체 재료의 영향)

  • 박상보
    • Journal of Powder Materials
    • /
    • v.5 no.1
    • /
    • pp.64-70
    • /
    • 1998
  • Milling media of steel and partially stabilized zirconia(PSZ) were used to produce $Mo_3$Si by mechanical alloying(MA) of Mo-25.0at%Si elemental powder mixture. The effect of milling medium materials on MA of the powder mixture have been investigated by XRD and DTA. The reaction rate and the end-product noticeably depended upon the milling medium material. The formation of $Mo_3$Si and $Mo_5Si_3$phases by PSZ ball-milling took place after 15 hr of MA and was characterized by a slow reaction rate as Mo, Si, $Mo_5Si_3$ and $Mo_3$Si coexisted for a long period of milling time. The formation of a new phase by steel ball-milling, however, did not take Place even after 96 hr of MA. DTA and annealing results showed that $Mo_5Si_3$ and $Mo_3$Si were formed after heating the ball-milled powder specimens to different temperatures. At low temperatures, Mo and Si were transformed into $Mo_5Si_3$. At high temperatures, the formation of $Mo_3$Si can be partially attributed to the reaction, 7Mo+Si+$Mo_5Si_3$-.4$Mo_3$Si . The formation of $Mo_3$Si and Mo5Si3 phases by mechanical alloying of the powder mixture and the relevant reaction rate appeared to depend upon the milling medium material as well as the thermodynamic properties of the end-products.

  • PDF

Annealing Effect in the Cold-Plastic Deformation of Amorphous PET Material (무정형 PET 재료의 플라스틱 냉간 변형에서의 열처리 효과)

  • Lee, Jong-Young;Park, Seong-Soo
    • Polymer(Korea)
    • /
    • v.25 no.1
    • /
    • pp.56-62
    • /
    • 2001
  • When polyethylene terephthalate(PET) film specimen were stepwise elongated under tension with various speeds of about 0.5~500 mm/min, the necking area, consisted of transparent and opaque bands, was formed during plastic deformation. Stress oscillation was apparently obtained in the stress-strain curve of above specimen. However, stress oscillation was not obtained in the stress-strain curve of annealing specimen. Microstructure was examined dynamically using an optical microscopy and thermal analysis was carried out in a differential scanning calorimeter at a heating rate of 10${\circ}$/min. Also, orientation and crystallization were examined using monochromatic-pinhole technique and elastic modulus was measured by a dynamic mechanical analyzer in the temperature range of -150~70 ${\circ}$ with the frequency of 1 Hz. Transparent PET products were fabricated by use of the PET pellets annealed at 83${\circ}$ for 30 min in an electric furnace.

  • PDF

Prevention of local overheating of a radiant tube heater (열처리용 복사튜브의 국부 과열 해소)

  • Kim H. S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2004.08a
    • /
    • pp.119-125
    • /
    • 2004
  • Radiant tube heaters are widely used for indirect heating in heat treatment processes such as continuous annealing line(CAL) or continuous galvanizing line(CGL). Main issues for radiant tube are temperature uniformity, lifetime, thermal efficiency. To achieve higher heat release, the radiant tubes are fired at a higher fuel rate and therefore local overheating occur. A numerical simulation based on a commercial code FLUENT has been performed to investigate local overheating of radiant tube heaters. To minimize local overheating, the effects of radiating fins, flue gas recirculation(FGR), two-stage combustion were investigated. More uniform temperature distribution was achieved in the longitudinal direction within the tube with radiating fins and this contributed to increase the life of radiant tubes. Furthermore, the radiant tube with radiating fins was proven to be more efficient than the one without fins. The effects of flue gas recirculation and two stage combustion on the efficiency of the radiant tube were also considered and the results were presented.

  • PDF

Analysis of the Changes of composition of Hardened Cement at High Temperature by X-Ray Diffraction (X-선 회절 분석을 통한 고온 피해 시멘트 경화체의 성분 변화 분석)

  • Ji, Woo-Ram;Park, Ji-Woong;Shin, Ki-Don;Lee, Gun-Cheol;Heo, Young-Sun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2017.11a
    • /
    • pp.113-114
    • /
    • 2017
  • In this study, the change of composition of cement hardened at high temperature through XRD was observed. The specimen was made of cement paste and the heating rate condition was applied at rapid thermal annealing (10.0℃ / min). The decrease of calcium hydroxide was not confirmed, but the calcium carbonate tended to be impossible or decreased after 800℃. Calcium silicate and larnite were observed to increase with increasing temperature. It is considered that silicic acid, which is a stable structure due to the decomposition of calcium silicate, is changed into a phase such as lime.

  • PDF

Fabrication and Characteristics of Hot-Film Type Micro-flowsensors integrated with RTD (측온저항체 온도센서가 집적화된 발열저항체형 마이크로 유량센서의 제작 및 특성)

  • 정귀상;홍석우
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.7
    • /
    • pp.612-616
    • /
    • 2000
  • This paper describes on the fabrication and characteristics of hot-film type micro-flowsensors integrated with Pt-RTD(resistance thermometer device) and micro-heater on the Si membrane in which MgO thin-film was used as medium layer in order to improve adhesion of Pt thin-film to SiO$_2$layer. The MgO layer improved adhesion of Pt thin-film to SiO$_2$layer without any chemical reactions to Pt thin-film under high annealing temperatures. Output voltages increased due to increase of heat-loss from sensor to external. The output voltage was 82 mV at $N_2$flow rate of 2000 sccm/min heating power of 1.2 W. The response time($\tau$:63%) was about 50 msec when input flow was stepinput

  • PDF