• Title/Summary/Keyword: high-temperature annealing

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The Study of Annealing Effect on the Dark Current of InGaAs Waveguide Photodiodes (InGaAs 도파로형 광다이오드의 암전류에 대한 열 처리 효과에 관한 연구)

  • Lee, Bong-Yong;Joo, Han-Sung;Yun, Il-Gu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.961-964
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    • 2003
  • This paper presents the temperature annealing effect on the dark current of the InGaAs waveguide photodiodes, which are developed for high-speed optical receivers. The interesting experimental phenomena were observed that the dark current is significantly decreased and the breakdown voltage is slightly increased after annealing at $250^{\circ}C$ whereas the dark current and the breakdown voltage are almost constant after annealing at $200^{\circ}C$. Based on the experimental results, the long-term annealing is more effective for the dark current improvement than the conventional curing process.

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Effects of Annealing Conditions of Corn Starch Slurry on the Formation of Phosphorylated Cross-linked Resistant Starch (옥수수 전분유의 Annealing 조건이 인산가교 저항 전분의 형성에 미치는 영향)

  • Bae, Chun-Ho;Park, Heui-Dong
    • Food Science and Preservation
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    • v.19 no.2
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    • pp.216-222
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    • 2012
  • The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.

Effects of Sputtering Condition on Structural Properties of PZT Thin Films on LTCC Substrate by RF Magnetron Sputtering (저온동시소성세라믹 기판 위에 제작된 PZT 박막의 증착조건이 박막의 구조적 특성에 미치는 영향)

  • Lee, Kyung-Chun;Hwang, Hyun-Suk;Lee, Tae-Yong;Hur, Won-Young;Song, Joon-Tae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.4
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    • pp.297-302
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    • 2011
  • Recently, low temperature co-fired ceramic (LTCC) technology is widely used in sensors, actuators and microsystems fields because of its very good electrical and mechanical properties, high reliability and stability as well as possibility of making 3D micro structures. In this study, we investigated the effects of sputtering gas ratio and annealing temperature on the crystal structure of $Pb(ZrTi)O_3$ (PZT) thin films deposited on LTCC substrate. The LTCC substrate with thickness of $400\;{\mu}m$ were fabricated by laminating 4 green tapes which consist of alumina and glass particle in an organic binder. The PZT thin films were deposited on Pt / Ti / LTCC substrates by RF magnetron sputtering method. The results showed that the crystallization of the films were enhanced as increasing $O_2$ mixing ratio. At about 25% $O_2$ mixing ratio, was well crystallized in the perovskite structure. PZT thin films was annealed at various temperatures. When the annealing temperature is lower, the PZT thin films become a phyrochlore phase. However, when the annealing temperature is higher than $600^{\circ}C$, the PZT thin films become a perovskite phase. At the annealing temperature of $700^{\circ}C$, perovskite PZT thin films with good quality structure was obtained.

Hydrothermal Growth and Characterization of ZnO Nanostructures on R-plane Sapphire Substrates (R-plane Sapphire 기판에 수열합성법으로 제작된 ZnO 나노구조체의 성장 및 특성)

  • Cho, Guan Sik;Kim, Min Su;Leem, Jae-Young
    • Korean Journal of Metals and Materials
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    • v.50 no.8
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    • pp.605-611
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    • 2012
  • ZnO nanostructures were grown on R-plane sapphire substrates with seed layers annealed at different temperatures ranging from 600 to $800^{\circ}C$. The properties of the ZnO nanostructures were investigated by scanning electron microscopy, high-resolution X-ray diffraction, UV-visible spectrophotometer, and photoluminescence. For the as-prepared seed layers, ZnO nanorods and ZnO nanosheets were observed. However, only ZnO nanorods were grown when the annealing temperature was above $700^{\circ}C$. The crystal qualities of the ZnO nanostructures were enhanced when the seed layers were annealed at $700^{\circ}C$. In addition, the full width at half maximum (FWHM) of near-band-edge emission (NBE) peak was decreased from 139 to 129 meV by increasing the annealing temperature to $700^{\circ}C$. However, the FWHM was slightly increased again by a further increase in the annealing temperature. Optical transmittance in the UV region was almost zero, while that in the visible region was gradually increased as the annealing temperature increased to $700^{\circ}C$. The optical band gap of the ZnO nanostructures was increased as the annealing temperature increased to $700^{\circ}C$. It is found that the optical properties as well as the structural properties of the rod-shaped ZnO nanostructures grown on R-plane sapphire substrates by hydrothermal method are improved when the seed layers are annealed at $700^{\circ}C$.

Effect of Processing Variables on the Texture of Ni Substrate for YBCO Coated Conductor (YBCO 박막선재용 Ni 기판의 집합도에 미치는 제조공정 변수효과)

  • 지봉기;임준형;이동욱;주진호;나완수;김찬중;홍계원
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.10
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    • pp.938-945
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    • 2003
  • We fabricated Ni-substrate for YBCO coated conductors and evaluated the effects of pressing and annealing temperature and time on texture. Ni substrate was fabricated by powder metallurgy technique and compacts were prepared by applying uniaxial or isostatic pressure. The texture of substrate made by applying cold isostatic pressure (CIP) was stronger than that by uniaxial pressure which we attribute to the fact that the CIP method provided higher density and more uniform density distribution. It was observed that the substrate annealed at 400 C showed both retained texture and recrystallized texture. On the other hand, the texture of substrate significantly improved at annealing temperature above 500 C, forming strong 4-fold symmetry, [111] II ND texture, and FWHM of 9∼10 . It is to be noted that the degree of texture was almost independent of annealing temperature (500∼1000 C) and annealing time(1∼54 min, at 1000 C). EBSD and AFM analysis indicated that 99% of grain boundaries was low angle grain boundary and RMS was approximately 3 nm, respectively. Development of strong cube texture and high fraction of low angle grain boundary of Ni-substrate made by powder metallurgy technique in our study is considered to be suitable for the application of YBCO coated conductors.

A Study on the Chemical Properties of AZO with Crystal Structure and IGZO of Amorphous Structure Due to the Annealing Temperature (결정질AZO 박막과 비정질IGZO 박막의 결정구조와 결합에너지와의 상관성)

  • So, Young Ho;Song, Jung Ho;Seo, Dong Myung;Oh, Teresa
    • Industry Promotion Research
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    • v.1 no.1
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    • pp.1-6
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    • 2016
  • To research the correlation between the amorphous and crystal structure of oxide semiconductors, AZO and IGZO films were deposited and annealed with various temperatures in a vacuum state. AZO increased the degree of crystal structure with increasing the annealing temperature, but IGZO became an amorphous structure after the annealing process at high temperature. The series of AZO films with various annealing temperatures showed the chemical shift from the analyzer of PL and O 1s spectra, but the results of IGZO films by PL and O 1s spectra were not observed the chemical shift. The binding energy of oxygen vacancy of AZO with a crystal structure was 531.5 eV, and that of IGZO with an amorphous structure was 530 eV as a lower binding energy.

Variation of Asymmetric Hysteresis Loops with Annealing Temperature and Time (열처리 온도와 시간에 따른 비대칭 자기 이력 곡선의 변화)

  • 신경호;민성혜;이장로
    • Journal of the Korean Magnetics Society
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    • v.5 no.4
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    • pp.251-260
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    • 1995
  • It has been reported that Co-based amorphous ferromagnetic alloys annealed in a small magnetic field develop a reproducible, asymmetric hysteresis loop. If the direction of the field during annealing is regarded as +, the magnetization reversal from - to + is smooth and reversible, with its slope determined by the demagnetizing field of the sample. This phenomenon is called the asymmetric magnetization reversal (AMR). The shape of the hyster-esis loop depends sensitively on the condition during the anneal and the alloy composition. Here, we report on the effect of the annealing temperature and time on AMR in a zero magnetostrictive ferromagnetic amorphous alloy. The AMR effect develops in a very short time at a reasonably high temperature, but is stabilized by annealing for a prolonged time.

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Characterization of Microstructure and Mechanical Properties of High-Purity Iron Added with Copper

  • Taguchi, O.;Lee, Su Yeon;Uchikoshi, M.;Isshiki, M.;Lee, Chan Gyu;Suzuki, S.;Gornakov, Vladimir S.
    • Journal of the Korean Society for Heat Treatment
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    • v.25 no.1
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    • pp.22-26
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    • 2012
  • An influence of the addition of copper (0.5, 1.0 and 1.5 mass% Cu) on the microstructure and mechanical properties of high purity iron (99.998 mass%) was characterized. The microstructure and microhardness of high-purity iron based samples, which were rolled at room temperature and subsequently annealed, were investigated in this work. The microstructure of the samples has been observed by electron back scattering diffraction (EBSD) and the mechanical properties have been studied by using micro-Vickers hardness test. The results of microstructural observation showed that deformation band was formed in high purity iron by rolling at room temperature, and it was recovered by annealing up to about 900 K. The microhardness results showed that the softening of high-purity iron occurred by annealing up to about 900 K, while the hardness of iron added with about 0.5-1.5 mass% copper was kept over 100 Hv and at the early time of annealing reached a maximum. The hardness of iron added with a small amount of copper may be attributed to precipitation hardening as well as solution hardening. The orientation of crystal in recrystallized grain was almost same as that of deformed grain.

Laser Thermal Processing System for Creation of Low Temperature Polycrystalline Silicon using High Power DPSS Laser and Excimer Laser

  • Kim, Doh-Hoon;Kim, Dae-Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.647-650
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    • 2006
  • Low temperature polycrystalline silicon (LTPS) technology using a high power laser have been widely applied to thin film transistors (TFTs) for liquid crystal, organic light emitting diode (OLED) display, driver circuit for system on glass (SOG) and static random access memory (SRAM). Recently, the semiconductor industry is continuing its quest to create even more powerful CPU and memory chips. This requires increasing of individual device speed through the continual reduction of the minimum size of device features and increasing of device density on the chip. Moreover, the flat panel display industry also need to be brighter, with richer more vivid color, wider viewing angle, have faster video capability and be more durable at lower cost. Kornic Systems Co., Ltd. developed the $KORONA^{TM}$ LTP/GLTP series - an innovative production tool for fabricating flat panel displays and semiconductor devices - to meet these growing market demands and advance the volume production capabilities of flat panel displays and semiconductor industry. The $KORONA^{TM}\;LTP/GLTP$ series using DPSS laser and XeCl excimer laser is designed for the new generation of the wafer & FPD glass annealing processing equipment combining advanced low temperature poly-silicon (LTPS) crystallization technology and object-oriented software architecture with a semistandard graphical user interface (GUI). These leading edge systems show the superior annealing ability to the conventional other method. The $KORONA^{TM}\;LTP/GLTP$ series provides technical and economical benefits of advanced annealing solution to semiconductor and FPD production performance with an exceptional level of productivity. High throughput, low cost of ownership and optimized system efficiency brings the highest yield and lowest cost per wafer/glass on the annealing market.

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A study on the c-axis orientation of ZnO thin film deposited on glass substrates (유리기판에 제작한 ZnO 박막의 c축 배향성에 관한 연구)

  • 고상춘;이종덕;송준태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.9-13
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    • 1995
  • In this paper, Zinc Oxide films, with a high degree of c-axis orientation, have been grown on glass substrates by a rf magnetron sputtering. The maximum crystal orientation was found to occur with substrate temperature 150$^{\circ}C$, input power 190W, oxygen rate 50%, target-substrate distance 55mm. It is proposed to achieve high-resistivity ZnO films by increasing the annealing temperature. The piezoelectric layers, preferred oriented with (002) perpendicular to the layer with 4.9$^{\circ}$, could be obtained by the annealing temperature 300$^{\circ}C$ in oxygen atmosphere. It is indicated that the relative permittivity is range from 8.9 to 9.8 in the frequency ranging from 10KHz to 5MHz.

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