理學院

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學院概況

理學院設有數學系、物理學系、化學系、生命科學系、地球科學系、資訊工程學系6個系(均含學士、碩士及博士課程),及科學教育研究所、環境教育研究所、光電科技研究所及海洋環境科技就所4個獨立研究所,另設有生物多樣性國際研究生博士學位學程。全學院專任教師約180人,陣容十分堅強,無論師資、學術長現、社會貢獻與影響力均居全國之首。

特色

理學院位在國立臺灣師範大學分部校區內,座落於臺北市公館,佔地約10公頃,是個小而美的校園,內含國際會議廳、圖書館、實驗室、天文臺等完善設施。

理學院創院已逾六十年,在此堅固基礎上,理學院不僅在基礎科學上有豐碩的表現,更在臺灣許多研究中獨占鰲頭,曾孕育出五位中研院院士。近年來,更致力於跨領域研究,並在應用科技上加強與業界合作,院內教師每年均取得多項專利,所開發之商品廣泛應用於醫、藥、化妝品、食品加工業、農業、環保、資訊、教育產業及日常生活中。

在科學教育研究上,臺灣師大理學院之排名更高居世界第一,此外更有獨步全臺的科學教育中心,該中心就中學科學課程、科學教與學等方面從事研究與推廣服務;是全國人力最充足,設備最完善,具有良好服務品質的中心。

在理學院紮實、多元的研究基礎下,學生可依其性向、興趣做出寬廣之選擇,無論對其未來進入學術研究領域、教育界或工業界工作,均是絕佳選擇。

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Now showing 1 - 7 of 7
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    Nanohomojunction (GaN) and nanoheterojunction (InN) nanorods on one-dimensional GaN nanowire substrates
    (Wiley-VCH Verlag, 2004-03-01) Z.-H. Lan; C.-H. Liang; C.-W. Hsu; C.-T. Wu; H.-M. Lin; S. Dhara; K.-H. Chen; L.-C. Chen; Chia-Chun Chen
    The formation of homojunctions and heterojunctions on two-dimensional (2D) substrates plays a key role in the device performance of thin films. Accelerating the progress of device fabrication in nanowires (NWs) also necessitates a similar understanding in the one-dimensional (1D) system. Nanohomojunction (GaN on GaN) and nanoheterojunction (InN on GaN) nanorods (NRs) were formed in a two-step growth process by a vapor–liquid–solid (VLS) mechanism. Ga2O3 nanoribbons were formed using Ni as catalyst in a chemical vapor deposition (CVD) technique and then completely converted to GaN NWs with NH3 as reactant gas. An Au catalyst is used in the second step of the VLS process to grow GaN and InN NRs on GaN NWs using CVD techniques. A morphological study showed the formation of nanobrushes with different structural symmetries and sub-symmetries in both homogeneous and heterogeneous systems. Structural characterizations showed nearly defect-free growth of nanohomojunction (GaN) and nanoheterojunction (InN) NRs on 1D GaN NW substrates.
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    Blueshift of yellow luminescence band in self-ion-implanted n-GaN nanowire
    (American Institute of Physics (AIP), 2004-05-03) S. Dhara; A Datta; C.-T. Wu; Z.-H. Lan; K.-H. Chen; Y. -L. Wang; Y.-F. Chen; C.-W. Hsu; L.-C. Chen; H.-M. Lin; Chia-Chun Chen
    Optical photoluminescence studies are performed in self-ion (Ga+)-implanted nominally dopedn-GaNnanowires. A 50 keV Ga+focused ion beam in the fluence range of 1×1014–2×1016 ions cm−2 is used for the irradiation process. A blueshift is observed for the yellow luminescence (YL) band with increasing fluence. Donor–acceptor pair model with emission involving shallow donor introduced by point-defect clusters related to nitrogen vacancies and probable deep acceptor created by gallium interstitial clusters is responsible for the shift. High-temperature annealing in nitrogen ambient restores the peak position of YL band by removing nitrogen vacancies.
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    Interband Optical Transitions in GaN Nanotubes Encapsulated GaP nanowires
    (AMERICAN PHYSICAL SOCIETY, 2003-04-30) M.-W. Lee; H.-C. Hseuh; H.-M. Lin; Chia-Chun Chen
    This work investigates the optical properties of cylindrical GaP nanowires encapsulated inside GaN nanotubes (GaP@GaN). Many absorption structures are observed in the range of 2.0–4 eV. Calculations are performed to determine the quantized energy levels of electrons and holes confined in the GaP well. Analytical results indicate that the absorption peaks are attributable to interband optical transitions due to the confined carriers in the heterostructure.
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    Synthesis and Characterization of Core-Shell GaP@GaN and GaN@GaP Nanowires
    (American Chemical Society, 2003-04-09) H.-M. Lin; Y.-L. Chen; J. Yang; Y.-C. Liu; K.-M. Yin; J.-J. Kai; F.-R. Chen; L.-C. Chen; Y.-F. Chen; Chia-Chun Chen
    A convenient thermal CVD route to core−shell GaP@GaN and GaN@GaP nanowires is developed. The structural analyses indicate that the nanowires exhibit a two-layer and wirelike structure. High-resolution transmission electron microscopy (HRTEM) images reveal misfit dislocation loops at the interface of the nanowires. Unusual temperature dependences of the photoluminescence (PL) intensity of GaP@GaN nanowires are observed, and they are interpreted by the piezoelectric effect induced from lattice mismatch between two semiconductor layers. In the Raman spectra of GaN@GaP nanowires, an unexpected peak at 386 cm-1 is found and assigned to a surface phonon mode.
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    Electronic Structure of GaN Nanowire Studied by x-ray-Absorption Spectroscopy and Scanning Photoelectron Microscopy
    (American Institute of Physics(AIP) Publishing, 2003-06-02) J.-W. Chiou; J.-C. Jan; H.-M. Tsai; W.-F. Pong; M.-H. Tsai; I.-H. Hong; R. Rklauser; J.-F. Lee; C.-W. Hsu; H.-M. Lin; Chia-Chun Chen; C.-H. Shen; L.-C. Chen; K.-H. Chen
    X-ray absorption near edge structure (XANES) and scanning photoelectron microscopy (SPEM) measurements have been employed to obtain information on the electronic structures of the GaN nanowires and thin film. The comparison of the XANES spectra revealed that the nanowires have a smaller (larger) N (Ga) K edge XANES intensity than that of the thin film, which suggests an increase (decrease) of the occupation of N 2p (Ga 4p) orbitals and an increase of the N (Ga) negative (positive) effective charge in the nanowires. The SPEM spectra showed that the Ga 3d band for the nanowires lies about 20.8 eV below the Fermi level and has a chemical shift of about -0.9 eV relative to that of the thin film. © 2003 American Institute of Physics.
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    Characterization of Nanodome on GaN Nanowires Formed with Ga Ion Irradiation
    (Nihon Kinzoku Gakkai, 2004-01-01) S. Muto; S. Dahara; A. Datta; C.-W. Hsu; C.-T. Wu; C.-H. Shen; L. -C. Chen; K.-H. Chen; Y.-L. Wang; T. Tanabe; T. Maruyama; H.-M. Lin; Chia-Chun Chen
    Structure of nano-domes formed by Ga+ ion irradiation with a focused ion beam (FIB) apparatus onto GaN nanowires (NWs) was examined with conventional transmission electron microscopy (CTEM), electron energy-loss spectroscopy (EELS) and energy-filtering TEM (EF-TEM). The nano-dome consisted of metallic gallium, covered by a GaN layer, the structure of which is amorphous or liquid. It is considered that the dome structure is formed by preferential displacement of lighter element (N) and agglomeration of heavier one (Ga). 1 MeV electron irradiation onto the sample pre-irradiated by Ga+ ions at a dose below the threshold for the dome formation induced the N2 bubble formation without segregating Ga atoms, which suggests the radiation-enhanced diffusion (RED) of heavy atoms plays an important role in the nano-dome formation.
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    Enhanced Dynamic Annealing in Ga+ ion-implanted GaN Nanowires
    (American Institute of Physics(AIP) Publishing, 2003-01-20) S. Dhara; A. Datta; C.-T. Wu; Z.-H. Lan; K.-H. Chen; Y.-L. Wang; L.-C. Chen; C.-W. Hsu; H.-M. Lin; Chia-Chun Chen
    Ga+ion implantation of chemical-vapor-deposited GaNnanowires (NWs) is studied using a 50-keV Ga+focused ion beam. The role of dynamic annealing (defect-annihilation) is discussed with an emphasis on the fluence-dependent defect structure. Unlike heavy-ion-irradiated epitaxialGaN film, large-scale amorphization is suppressed until a very high fluence of 2×1016 ions cm−2. In contrast to extended-defects as reported for heavy-ion-irradiated epitaxialGaN film, point-defect clusters are identified as major component in irradiated NWs. Enhanced dynamic annealing induced by high diffusivity of mobile point-defects in the confined geometry of NWs is identified as the probable reason for observed differences.