• 제목/요약/키워드: laser writing

검색결과 86건 처리시간 0.037초

Fabricating a Micro-Lens Array Using a Laser-Induced 3D Nanopattern Followed by Wet Etching and CO2 Laser Polishing

  • Seung-Sik Ham;Chang-Hwam Kim;Soo-Ho Choi;Jong-Hoon Lee;Ho Lee
    • 한국산업융합학회 논문집
    • /
    • 제26권4_1호
    • /
    • pp.517-527
    • /
    • 2023
  • Many techniques have been proposed and investigated for microlens array manufacturing in three-dimensional (3D) structures. We present fabricating a microlens array using selective laser etching and a CO2 laser. The femtosecond laser was employed to produce multiple micro-cracks that comprise the predesigned 3D structure. Subsequently, the wet etching process with a KOH solution was used to produce the primary microlens array structures. To polish the nonoptical surface to the optical surface, we performed reflow postprocessing using a CO2 laser. We confirmed that the micro lens array can be manufactured in three primary shapes (cone, pyramid and hemisphere). Compared to our previous study, the processing time required for laser processing was reduced from approximately 1 hour to less than 30 seconds using the proposed processing method. Therefore, micro lens arrays can be manufactured using our processing method and can be applied to mass productionon large surface areas.

펨토초레이저를 이용한 알루미늄 성형다이의 미세가공에 관한 연구 (Die Surface Texturing by Femtosecond Laser for Friction Reduction)

  • 최해운;신현명
    • 한국정밀공학회지
    • /
    • 제26권5호
    • /
    • pp.57-63
    • /
    • 2009
  • Interface friction in blanking dies, cold forging and extrusion of aluminum alloys is a major cause of inefficient process. This paper describes an investigation of femtosecond laser texturing for reduction of interface friction on sliding surfaces in forming process. Femtosecond direct writing technology was used to fabricate a laser micro-machined die and to create microgroove patterns with varying size and density on metal forming dies. A systematic approach to find the optimum parameters and computer simulation comparison of friction coefficients are provided to study the relation of friction coefficients and die profiles. In metal forming tests, the effectiveness of various laser-machined patterns for enhancing interface lubrication is determined.

Flexible Active-Matrix Electrophoretic Display With Integrated Scan-And Data-Drivers

  • Miyazaki, Atsushi;Kawai, Hideyuki;Miyasaka, Mitsutoshi;Inoue, Satoshi;Shimoda, Tatsuya
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
    • /
    • pp.153-156
    • /
    • 2004
  • A newly developed flexible active-matrix (AM-) electrophoretic display (EPD) is reported. The AM-EPD features: (1) low-temperature polycrystalline silicon (LTPS) thin film transistor (TFT) technology, (2) fully integrated scan- and data-drivers, (3) flexibility and light-weight realized by transferring the whole circuits onto a plastic substrate using $SUFTLA^{TM}$ (Surface Free Technology by Laser Annealing/Ablation) process. A large storage capacitor is formed in each pixel so that driving electric field can be kept sufficiently strong during a writing period Two-phase driving scheme, a reset-phase which erases a previous image and a writing-phase for writing a new image, was chosen to cope with EPD's high driving voltage. The flexible AM-EPD has been successfully operated with a driving voltage of 8.5 V.

  • PDF

레이저에 의한 실리콘 표면의 습윤성 향상과 구리 패터닝 (Laser Copper Patterning by wettability improvement of Silicon)

  • 김동용;이경철;이천
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
    • /
    • pp.1080-1083
    • /
    • 2002
  • In this paper, we have studied with regard to the use of lasers for modifying the surface properties of silicon in order to improve it's wettability and adhesion characteristics. Using an Nd:YAG pulse laser, the wettability and adhesion characteristics of silicon surface have been developed by an Nd:YAG pulse laser. It was found that the laser treatment of silicon surfaces modified the surface energy. In the result of wetting experiments, by the sessile drop technique using the distilled water, wetting characteristic of silicon after the laser irradiation shows a decreased value of the contact angle. In case of the laser treated silicon surface, laser direct writing of copper lines has been achieved by pyrolytic decomposition of copper formate films$(Cu(HCOO)_2{\cdot}4H_2Q)$, using a focused $Ar^+$ laser beam$(\lambda=514.5nm)$ on the silicon substrates. The deposited patterns were measured by energy dispersive X-ray(EDX), Scanning Electron Microscopy(SEM) and surface profiler($\alpha$-step) to examine the cross section of deposited copper lines and linewidth.

  • PDF

레이저 미세 가공 공정에서 광센서를 이용한 선폭 예측을 위한 통계적 모델의 개발 (Development of Statistical Model for Line Width Estimation in Laser Micro Material Processing Using Optical Sensor)

  • 박영환;이세헌
    • 한국정밀공학회지
    • /
    • 제22권7호
    • /
    • pp.27-37
    • /
    • 2005
  • Direct writing technology on the silicon wafer surface is used to reduce the size of the chip as the miniature trend in electronic circuit. In order to improve the productivity and efficiency, the real time quality estimation is very important in each semiconductor process. In laser marking, marking quality is determined by readability which is dependant on the contrast of surface, the line width, and the melting depth. Many researchers have tried to find theoretical and numerical estimation models fur groove geometry. However, these models are limited to be applied to the real system. In this study, the estimation system for the line width during the laser marking was proposed by process monitoring method. The light intensity emitted by plasma which is produced when irradiating the laser to the silicon wafer was measured using the optical sensor. Because the laser marking is too fast to measure with external sensor, we build up the coaxial monitoring system. Analysis for the correlation between the acquired signals and the line width according to the change of laser power was carried out. Also, we developed the models enabling the estimation of line width of the laser marking through the statistical regression models and may see that their estimating performances were excellent.

폴리머의 엑시머레이저 어블레이션에 관한 연구 (A study of excimer laser ablation of polymer)

  • 신동식;이제훈;서정;김도훈
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2003년도 춘계학술대회 논문집
    • /
    • pp.1857-1860
    • /
    • 2003
  • The ablative decomposition mechanism of PMMA(polymethyt methacrylate), PET(polyethylene terephthalate) and PC(polycarbonate) with KrF excimer laser(λ: 248nm, pulse duration: 5ns) is investigated. The UV/Vis spectrometer analysis showed that PMMA is a weak absorber and PET, PC are a strong absorber at the wavelength of 248nm. The results(surface debris, melt, etch depth, etching shape) from drilling and direct writing experiments imply that ablation mechanism of PMMA is dominated by photothermal process, while that of PET, PC are dominated by photochemical process.

  • PDF

Nano-structuring of Transparent Materials by Femtosecond Laser Pulses

  • Sohn, Ik-Bu;Lee, Man-Seop;Chung, Jung-Yong;Cho, Sung-Hak
    • Journal of the Optical Society of Korea
    • /
    • 제9권1호
    • /
    • pp.1-5
    • /
    • 2005
  • Using tightly focused femtosecond laser pulses, we produce an optical waveguide and optical devices in transparent materials. This technique has the potential to generate not only channel waveguides, but also three-dimensional optical devices. In this paper, an optical splitter and U-grooves, which are used for fiber alignment, are simultaneously fabricated in a fused silica glass using near-IR femtosecond laser pulses. The fiber aligned optical splitter has a low insertion loss, less than 4㏈, including an intrinsic splitting loss of 3㏈ and excess loss due to the passive alignment of a single-mode fiber. Finally, we demonstrate the utility of the femtosecond laser writing technique by fabricating gratings at the surface and inside the silica glass.

Femtosecond Laser Application to PLC Optical Devices and Packaging

  • Sohn, Ik-Bu;Lee, Man-Seop;Lee, Sang-Man
    • ETRI Journal
    • /
    • 제27권4호
    • /
    • pp.446-448
    • /
    • 2005
  • Using tightly focused femtosecond laser pulses, we produce an optical waveguide and devices in transparent materials. This technique has the potential to generate not only channel waveguides, but also three-dimensional optical devices. In this paper, an optical splitter and U-grooves, which are used for fiber alignment, are simultaneously fabricated in a fused silica glass using near-IR femtosecond laser pulses. The fiber- aligned optical splitter has a low insertion loss, less than 4 dB, including an intrinsic splitting loss of 3 dB and excess loss due to the passive alignment of a single-mode fiber. Finally, we present an output field pattern, demonstrating that the splitting ratio of the optical splitter becomes approximately 1:1.

  • PDF