Through holes (THs) with different shapes were formed by laser drilling on a printed circuit board to evaluate the filling capability of two copper plating formulas. The shapes of these THs were cylindrical, V- and X-shaped. Two copper plating formulas, accelerator-free formula (AFF) and accelerator-containing formula (ACF), were employed in this work. The AFF contained only one organic additive and the ACF was composed of multiorganic additives. The electrochemical characteristics of the AFF were investigated by cyclic voltammetry, which could be utilized to explain the results of filling plating. The plating results showed that the cylindrical TH could be fully filled using AFF. However, the V- and X-shaped THs could be fully filled using ACF. TH and microvias could be simultaneously filled in one plating bath using the AFF. A filling mechanism based on an adsorption/consumption/diffusion mode was proposed to explain these plating results. (C) 2008 The Electrochemical Society. [DOI: 10.1149/1.2988134] All rights reserved

[1] Geochemical data (CH 4 , SO 4 2À , IÀ , Cl À , particulate organic carbon (POC), 13 C-CH 4 , and 13 C-CO 2 ) are presented from the upper 30 m of marine sediment on a tectonic submarine accretionary wedge offshore southwest Taiwan. The sampling stations covered three ridges (Tai-Nan, Yung-An, and Good Weather), each characterized by bottom simulating reflectors, acoustic turbidity, and different types of faulting and anticlines. Sulfate and iodide concentrations varied little from seawater-like values in the upper 1-3 m of sediment at all stations ; a feature that is consistent with irrigation of seawater by gas bubbles rising through the soft surface sediments. Below this depth, sulfate was rapidly consumed within 5-10 m by anaerobic oxidation of methane (AOM) at the sulfate-methane transition. Carbon isotopic data imply a mainly biogenic methane source. A numerical transport-reaction model was used to identify the supply pathways of methane and estimate depth-integrated turnover rates at the three ridges. Methane gas ascending from deep layers, facilitated by thrusts and faults, was by far the dominant term in the methane budget at all sites. Differences in the proximity of the sampling sites to the faults and anticlines mainly accounted for the variability in gas fluxes and depth-integrated AOM rates. By comparison, methane produced in situ by POC degradation within the modeled sediment column was unimportant. This study demonstrates that the geochemical trends in the continental margins offshore SW Taiwan are closely related to the different geological settings.

No abstract

Kueishantao is a Holocene volcanic islet (<7,000 yrs) located at NE offshore Taiwan, and tectonically is part of western extension of the Okinawa Trough. Magmatic activities are considered very active around this area on the basis of the fact that on-land fumaroles and submarine hydrothermal systems are prevailing currently. Representative bubble gas samples from submarine hydrothermal vents were collected for gas composition and helium isotope analysis. The gases show similar compositions of low temperatre fumaroles in the world, i.e., with high CO 2 and H 2 S but low SO 2 and HCl contents. They exhibit consistent high 3 He/ 4 He ratios (7.3-8.4 R A , where R A is the 3 He/ 4 He ratio of air), probably the highest 3 He/ 4 He values of gases ever reported in active hydrothermal areas of the western Pacific region. Meanwhile, seawater samples around Kueishantao and other fluid samples from I-Lan Plain, the land area closest to the Kueishantao and also the southernmost part of the Okinawa Trough, show a significant excess of 3 He compositions as well. This indicates that the mantle component plays an important role for their gas sources, and implies that the mantle fluids may have invaded into I-Lan Plain. The westward opening of the Okinawa Trough may have caused thinning of the continental crust and produced deep normal faults and hence, the primordial 3 He is able to degas from mantle source region without significant crust contamination.