• Title/Summary/Keyword: optical annealing

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Reduction of Reconstruction Errors in Kinoform CGHs by Modified Simulated Annealing Algorithm

  • Yang, Han-Jin;Cho, Jeong-Sik;Won, Yong-Hyub
    • Journal of the Optical Society of Korea
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    • v.13 no.1
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    • pp.92-97
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    • 2009
  • In this paper, a conventional simulated annealing (SA) method for optimization of a kinoform computer generated hologram (CGH) is analyzed and the SA method is modified to reduce a reconstruction error rate (ER) of the CGH. The dependences of the quantization level of the hologram pattern and the size of the data on the ER are analyzed. To overcome saturation of the ER, the conventional SA method is modified as it magnifies a Fourier-transformed pattern in the intermediate step. The proposed method can achieve a small ER less than 1%, which is impossible in the conventional SA method.

OptiNeural System for Optical Pattern Classification

  • Kim, Myung-Soo
    • Journal of Electrical Engineering and information Science
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    • v.3 no.3
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    • pp.342-347
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    • 1998
  • An OptiNeural system is developed for optical pattern classification. It is a novel hybrid system which consists of an optical processor and a multilayer neural network. It takes advantages of two dimensional processing capability of an optical processor and nonlinear mapping capability of a neural network. The optical processor with a binary phase only filter is used as a preprocessor for feature extraction and the neural network is used as a decision system through mapping. OptiNeural system is trained for optical pattern classification by use of a simulated annealing algorithm. Its classification performance for grey tone texture patterns is excellent, while a conventional optical system shows poor classification performance.

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The Effects of Annealing Temperature on The Physical Properties and Fine Structure of Poly(trimethylene terephthalate)(PTT) Fibers (열처리 온도가 Poly(trimethylene terephthalate)(PTT) 섬유의 역학적 성질과 미세구조에 미치는 효과)

  • Jeong, Kyung Hui;Lee, Eon Pil;Lee, Jae Ho
    • 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.

Optical Properties of Silicon Oxide (SiOx, x<2) Thin Films Deposited by PECVD Technique (PECVD 방법으로 증착한 SiOx(x<2) 박막의 광학적 특성 규명)

  • Kim, Youngill;Park, Byoung Youl;Kim, Eunkyeom;Han, Munsup;Sok, Junghyun;Park, Kyoungwan
    • Korean Journal of Metals and Materials
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    • v.49 no.9
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    • pp.732-738
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    • 2011
  • Silicon oxide thin films were deposited by using a plasma-enhanced chemical-vapor deposition technique to investigate the light emission properties. The photoluminescence characteristics were divided into two categories along the relative ratio of the flow rates of $SiH_4$ and $N_2O$ source gases, which show light emission in the broad/visible range and a light emission peak at 380 nm. We attribute the broad/visible light emission and the light emission peak to the quantum confinement effect of nanocrystalline silicon and the Si=O defects, respectively. Changes in the photoluminescence spectra were observed after the post-annealing processes. The photoluminescence spectra of the broad light emission in the visible range shifted to the long wavelength and were saturated above an annealing temperature of $900^{\circ}C$ or after 1 hour annealing at $970^{\circ}C$. However, the position of the light emission peak at 380 nm did not change at all after the post-annealing processes. The light emission intensities at 380 nm initially increased, and decreased at annealing temperatures above $700^{\circ}C$ or after 1 hour annealing at $700^{\circ}C$. The photoluminescence behaviors after the annealing processes can be explained bythe size change of the nanocrystalline silicon and the density change of Si=O defect in the films, respectively. These results support the possibility of using a silicon-based light source for Si-optoelectronic integrated circuits and/or display devices.

Current Variation in ZnO Thin-Film Transistor under Different Annealing Conditions (ZnO 박막트랜지스터의 어닐링 조건에 따른 전류 변화)

  • Yoo, Dukyean;Kim, Hyoungju;Kim, Junyeong;Jo, Jungyol
    • Journal of the Semiconductor & Display Technology
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    • v.13 no.1
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    • pp.63-66
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    • 2014
  • ZnO is a wide bandgap (3.3 eV) semiconductor with high mobility and good optical transparency. However, off-current characteristics of ZnO thin-film transistor (TFT) need improvements. In this work we studied the variation in ZnO TFT current under different annealing conditions. Annealing usually modifies gas adsorption at grain boundaries of ZnO. When oxygen is adsorbed, electron density decreases due to strong electronegativity of the oxygen, and TFT current decreases as a result. Our experiments showed that current increased after vacuum annealing and decreased after air annealing. We explain that the change of off-current is caused by the desorption and adsorption of oxygen at the grain boundaries.

Bonding Property of Silicon Wafer Pairs with Annealing Method (열처리 방법에 따른 실리콘 기판쌍의 접합 특성)

  • 민홍석;이상현;송오성;주영창
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.5
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    • pp.365-371
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    • 2003
  • We prepared silicon on insulator(SOI) wafer pairs of Si/1800${\AA}$ -SiO$_2$ ∥ 1800${\AA}$ -SiO$_2$/Si using water direct bonding method. Wafer pairs bonded at room-temperature were annealed by a normal furnace system or a fast linear annealing(FLA) equipment, and the micro-structure of bonding interfaces for each annealing method was investigated. Upper wafer of bonded pairs was polished to be 50 $\mu\textrm{m}$ by chemical mechanical polishing(CMP) process to confirm the real application. Defects and bonding area of bonded water pairs were observed by optical images. Electrical and mechanical properties were characterized by measuring leakage current for sweeping to 120 V, and by observing the change of wafer curvature with annealing process, respectively. FLA process was superior to normal furnace process in aspects of bonding area, I-V property, and stress generation.

Effect of thermal annealing on optical and electrical properties of VOx deposited by magnetron sputtering (마그네트론 스퍼터링법으로 증착한 VOx 박막의 열처리에 따른 광학적.전기적 특성 변화)

  • Kong, Young-Joo;Park, Yong-Seob;Park, Jae-Wook;Lee, Sung-Uk;Hong, Byung-You
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.247-247
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    • 2008
  • In this work, VOx thin films have been deposited by DC magnetron sputtering method on glass substrate using argon and oxygen gases. We examined the effects of the post annealing temperature on the structural, optical, and electrical variations of VOx films. The films were annealed at temperatures ranging from 300 to $500^{\circ}C$ in steps of $100^{\circ}C$ using RTA equipment in air ambient. The thickness of the film and interface between film and substrate were observed by field emission scanning electron microscopy (FESEM). To analysis the structural properties of VOx with various annealng temperatures, we used XRD method. Also, we investigated the electrical and optical properties of VOx thin films using hall measurement, 4-point probe, and UV-visible methods.

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Effect of annealing on the structural, electrical and optical characteristics of Ga-doped ZnO(GZO)films (Ga doped ZnO 박막의 열처리 조건에 따른 전기적 특성에 관한 연구)

  • Oh, Su-Young;Kim, Eung-Kwon;Lee, Tae-Yong;Kang, Hyun-Il;Kim, Dong-Hwan;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.261-262
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    • 2007
  • In this study we present the effect of annealing temperatures on the structural, electrical and optical characteristics of Ga-doped ZnO(GZO) films. GZO target have been deposited on corning 7059 glass substrates by DC sputtering. GZO films were annealed at temperatures of 400, 500, $600^{\circ}C$ in air ambient for 20 min. Experimental resulted in as-grown film shows the resistivity of $6{\times}10^{-1}\;{\Omega}{\cdot}cm$ and transmittance under 85%, whereas the electrical and optical properties of film annealed at $500^{\circ}C$ are enhanced up to $1.9{\times}10^{-3}\;{\Omega}{\cdot}cm$ and 90%, respectively.

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Effects of the mosture and thermal annealing on CLBO crystal

  • Mori, Yusuke;Sasaki, Takatomo
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1997.06a
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    • pp.125-129
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    • 1997
  • The effects of the moisture and thermal annealing on CLBO crystal have been investigated. CLBO has hydrated at high humidity condition, resulting in 5B$_2$O$_3$$.$Cs$_2$O$.$8H$_2$O. The surface hydration seems to induce the cracking and the refractive index change in CLBO. The thermal annealing is effective to restore the changed index.

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UV Optical Solutions for Thin Film Processing and Annealing Research

  • Delmdahl, Ralph;Shimizu, Hiroshi;Dittmar, Mirko;Fechner, Burkhard
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.246-249
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    • 2009
  • A compact, flexible family of UV laser material processing systems has been developed to drive advancements in both large area processing and annealing of semiconductor surfaces. UV photons can either be applied via demagnifying a mask pattern image or by scanning a homogenized excimer beam across the substrate area. 193nm, 248nm and 308nm wavelength applications are supported.

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