Time filter

Source Type

Kaohsiung, Taiwan

Liang C.-H.,Walsin Technology Corporation | Hsiao Y.-J.,National Nano Device Laboratories | Hwang W.-S.,National Cheng Kung University
Thin Solid Films | Year: 2016

Ga-doped ZnO (GZO) films with various thicknesses (105–490 nm) were deposited on PET substrates at a low temperature of 90 °C by a steered cathodic arc plasma evaporation (steered CAPE), and a GZO film with a thickness of 400 nm was deposited at 90 °C by a magnetron sputtering (MS) for comparison. The comparative analysis of the microstructure, residual stress, surface morphology, electrical and optical properties, chemical states, and doping efficiency of the films produced by the steered CAPE and MS processes was performed, and the effect of thickness on the CAPE-grown GZO films was investigated in detail. The results showed that the GZO films grown by steered CAPE exhibited higher crystallinity and lower internal stress than those deposited by MS. The transmittance and electrical properties were also enhanced for the steered CAPE-grown films. The figure of merit (Φ = T10/Rs, where T is the transmittance and Rs is the sheet resistance in Ω/□). was used to evaluate the performance of the electro-optical properties. The GZO films with a thickness of 400 nm deposited by CAPE had the highest Φ value, 1.94 × 10− 2 Ω− 1, a corresponding average visible transmittance of 88.8% and resistivity of 6.29 × 10− 4 Ω·cm. In contrast, the Φ value of MS-deposited GZO film with a thickness of 400 nm is only 1.1 × 10− 3 Ω− 1. This can be attributed to the increase in crystalline size, [0001] preferred orientation, decrease in stacking faults density and Ar contamination in steered CAPE-grown films, leading to increases in the Hall mobility and carrier density. In addition, the power conversion efficiency (PCE) of organic solar cells was significantly improved by using the CAPE-grown GZO electrode, and the PCE values were 1.2% and 1.7% for the devices with MS-grown and CAPE-grown GZO electrodes, respectively. © 2016 Elsevier B.V. Source

Hong J.-Y.,Walsin Technology Corporation | Lu H.-Y.,National Sun Yat - sen University
Journal of the American Ceramic Society | Year: 2014

Commercial EIA-Y5V base-metal-electrode multilayer ceramic capacitors (BME-MLCCs) made of (CaO+ZrO2)-doped BaTiO3 are analyzed for the microstructure and investigated for its relation to dielectric properties. The characteristic diffuse scattering (DS) intensities observed in BaTiO3 ceramics and the featureless "solid-solution" grains in Y5V capacitor chips are originated from multiple Ti sites in the dynamic BaTiO3 structure. The pseudo-cubic (PC)-grains retaining the overall cubic (C-) symmetry metastably at room temperature are embedded with polar nanoregions (PNRs) in the ferroelectric (FE) tetragonal (T-), and rhombohedral (R-) phases, as revealed by high-resolution transmission electron microscopy (HRTEM). The presence of PNRs contributes effectively to large relative permittivity εr ≈ 13 200 at 25°C. The FE T-domains grow from within PC-grains at the expense of embedded PNRs after prolonged annealing by extending "oxidizing firing" at 950°C in pO2 = 10-7 atm. These domains contain less Zr with otherwise homogeneously distributed solutes in PNR-dispersed PC-grains. Although preserving the relaxors characteristics, εr is reduced to ~11 000 after 12 h, and then to ~9000 after 24 h annealing. The reduction in εr is attributed to the annealing-induced FE T-domains grown at the expense of PNRs in PC-grains. The Vögel-Fulcher analysis indicates that Y5V ceramics are in the relaxor FE category, containing PNRs derived from polarization frustration. © 2014 The American Ceramic Society. Source

Pan W.-H.,National Taiwan University | Kuo S.-T.,National Taiwan University | Tuan W.-H.,National Taiwan University | Chen H.-R.,Walsin Technology Corporation
International Journal of Applied Ceramic Technology | Year: 2010

The low-voltage varistors with various layer thickness are prepared by laminating thin ZnO-based ceramic layers and AgPd electrodes together. The breakdown voltage dose not exhibit linear relationship with layer thickness. It is due to that the presence of the AgPd electrodes enhances the growth of ZnO grains. As some ZnO grains are large enough to touch the upper and lower electrodes, the breakdown voltage of the varistor is only 3.7 V. The nonlinear coefficient of the low-voltage varistor is 33. Such nonlinear current-voltage behavior is mainly contributed by the interface between the AgPd electrode and ZnO grains. © 2009 The American Ceramic Society. Source

Chou C.-C.,National Taiwan University of Science and Technology | Chen C.-S.,Hwa Hsia University of Technology | Wu P.-C.,National Taiwan University of Science and Technology | Feng K.-C.,National Taiwan University of Science and Technology | Chu L.-W.,Walsin Technology Corporation
Ceramics International | Year: 2012

BaTi 4O 9 (BT4) dielectric ceramics, containing 10 wt% BaO-ZnO-B 2O 3-SiO 2 (BZBS) glass frit as sintering aid were co-fired with copper paste under reducing atmosphere at 950°C and investigated on microstructures and dielectric properties. Experimental results show the microstructures and microwave dielectric properties of BT4-BZBS glass composite materials are strongly dependent on the Ba-Zn-B-Si ratio, especially for the content of SiO 2 addition, in BZBS glass. XRD and EDS results indicate that Cu reacts with BZBS glass-added BT4 ceramics seriously to form complicated reaction products such as BaCuO 2 phase, when the BZBS glass composition with lower content of SiO 2 (less than 20 wt%), and transformation of some BaTi 4O 9 into barium titanate with various ratios of Ba/Ti, which, fortunately, does not seriously degrade the dielectric properties. © 2011 Elsevier Ltd and Techna Group S.r.l. Source

Chiang P.-Y.,National Chiao Tung University | Su C.-W.,National Chiao Tung University | Luo S.-Y.,Walsin Technology Corporation | Hu R.,National Chiao Tung University | Jou C.F.,National Chiao Tung University
IEEE Transactions on Microwave Theory and Techniques | Year: 2010

A wide-IF-band transistor mixer has been designed using a 0.13-μm RF-CMOS process where its RF frequency is 8.717.4 GHz, local oscillator (LO) fixed at 17.4 GHz, and IF up to 8.7 GHz. Proper layout arrangement for the Marchand balun has been discussed and then implemented; the output amplitude and phase imbalance are less than 0.5 dB and 1° measured in the RF bandwidth. Related theories for the core mixing circuit are explored extensively and verified through simulation; broad bandwidth of the resistive double-balanced mixer is then confirmed in the IF aspect. The designed mixer has more than 10-dB conversion gain, matched RF, IF, and LO ports, and good port isolation over the intended wide bandwidth. The input-referred P1 dB is -17.5 dBm at 9 GHz and -16 dBm at 13 GHz. The third-order input intercept point is -6 dBm at 9 GHz and -5 dBm at 13 GHz. The noise figure is 7 dB at 9 GHz and 12.6 dB at 13 GHz. The power consumption is 40 mW for this 1.3-mm2 mixer chip. © 2006 IEEE. Source

Discover hidden collaborations