Tetsu Tanaka

Bio: Tetsu Tanaka is an academic researcher from Tohoku University. The author has contributed to research in topics: Wafer & Chip. The author has an hindex of 38, co-authored 406 publications receiving 10375 citations. Previous affiliations of Tetsu Tanaka include NTT DoCoMo & Tokyo Medical and Dental University.

TSV liner dielectric technology with spin-on low-k polymer

Abstract: In this paper, a BCB (benzocyclobutene) resin is employed as a spin-on low-k polymer for TSV liner dielectrics. The BCB is perfectly covered on the sidewall of deep Si holes with a diameter of 8 μm and depth of 40 μm (aspect ratio: 5). The step coverage of the BCB is high and controllable by conditioning the spin rotation speed, spin-coating time, and deforming pressure to eliminate bubbles formed in the deep Si holes prior to spin-coating. Cu-TSVs with the BCB liner dielectric are successfully formed by the subsequent electro-less plated and electroplated Cu technologies. This cost-effective spin-on BCB technology will be applied to via-last TSV fabrication at low temperature below 250 C to give low-capacitance TSVs.

Early response of right-ventricular function to percutaneous mitral valve repair.

Abstract: BACKGROUND The change in right-ventricular function (RVF) after transcatheter mitral valve repair is still poorly understood. We assessed the early response of RVF to the MitraClip procedure and its clinical relevance. METHODS We analyzed consecutive patients who underwent a MitraClip procedure to treat MR between August 2010 and March 2019 in the Heart Failure Network Rhineland registry. RVF was assessed before and after the procedure. Impaired RVF was defined as an RV fractional area change (RVFAC) < 35% or tricuspid annular plane systolic excursion (TAPSE) < 16 mm. RESULTS 816 eligible patients (77 ± 9 years, 58.5% male) were included in the analysis. Baseline values of RVF were: RVFAC 38.6 (IQR 29.7-46.7) % and TAPSE 17.0 (IQR 14.0-21.0) mm. At a median time of 3 (IQR 2-5) days after the procedure, the RVF remained normal in 34% (n = 274), normalized in 17% (n = 140), deteriorated in 15% (n = 125), and was persistently impaired in 34% (n = 277) of patients. The RVF response was significantly associated with a composite outcome of all-cause mortality and hospitalization due to heart failure within a 2-year follow-up. Compared to stable/normal RVF, the adjusted hazard ratios for the outcome were 1.78 (95% CI 1.10-2.86) for normalized RVF, 1.89 (95% CI 1.34-3.15) for deteriorated RVF, and 2.25 (95% CI 1.47-3.44) for persistently impaired RVF. Changes in TAPSE and RVFAC as continuous variables were significantly correlated with the outcome. CONCLUSION An early change in RVF following transcatheter mitral valve repair is predictive of mortality and hospitalization due to heart failure during follow-up. Early response of RVF after MitraClip and its clinical significance. An acute, early change in RVF can be observed following the MitraClip procedure, which is associated with the risk of mortality and hospitalization for HF.

Temporary bonding strength control for self-assembly-based 3D integration

Abstract: We have demonstrated bonding strength control for self-assembly-based 3D integration in which many chips are instantly assembled on a wafer all at once by using liquid droplets, and then, temporarily bonded to the wafer. The wafer is named Reconfigured Wafer. The self-assembly-based multichip-to-wafer 3D stacking is called reconfigured-wafer-to-wafer 3D integration. The alignment accuracy is found to be within 1 μm and the temporal bonding strength is well controlled by the quality of oxides as a bonding interface material, liquid types (concentration of additives), total bonding area, and surface roughness of the oxides. The self-assembled and temporarily bonded chips are successfully transferred to another wafer in a face-to-face bonding manner in batch processing.

Drastic reduction of keep-out-zone in 3D-IC by local stress suppression with negative-CTE filler

Abstract: Three-dimensional IC (3D IC) is a promising method to enhance IC performance. Conventional 3D ICs consist of vertically stacked several thin IC chips those are electrically connected with lots of through-Si vias (TSVs) and metal microbumps. Metal microbumps are surrounded by organic adhesive. An epoxy-based material, so-called underfill, has been widely used to fill the gap between several chips. In general, coefficient of thermal expansion (CTE) of the underfill material is larger than that of metal microbumps. This CTE mismatch induces local bending stress in thinned IC chips. This local bending stress would affect CMOS circuit in thinned IC chips. Therefore, we should suppress the local bending stress to realize 3D IC with high reliability. In this work, we propose a novel underfill with negative-CTE filler which can suppress the local bending stress in 3D IC.

Deciphering the biology of Mycobacterium tuberculosis from the complete genome sequence

Abstract: Countless millions of people have died from tuberculosis, a chronic infectious disease caused by the tubercle bacillus. The complete genome sequence of the best-characterized strain of Mycobacterium tuberculosis, H37Rv, has been determined and analysed in order to improve our understanding of the biology of this slow-growing pathogen and to help the conception of new prophylactic and therapeutic interventions. The genome comprises 4,411,529 base pairs, contains around 4,000 genes, and has a very high guanine + cytosine content that is reflected in the biased amino-acid content of the proteins. M. tuberculosis differs radically from other bacteria in that a very large portion of its coding capacity is devoted to the production of enzymes involved in lipogenesis and lipolysis, and to two new families of glycine-rich proteins with a repetitive structure that may represent a source of antigenic variation.

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Abstract: BackgroundExperimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. MethodsWe conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. ResultsAt 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in t...

Complete genome sequence of Pseudomonas aeruginosa PAO1, an opportunistic pathogen.

Abstract: Pseudomonas aeruginosa is a ubiquitous environmental bacterium that is one of the top three causes of opportunistic human infections. A major factor in its prominence as a pathogen is its intrinsic resistance to antibiotics and disinfectants. Here we report the complete sequence of P. aeruginosa strain PAO1. At 6.3 million base pairs, this is the largest bacterial genome sequenced, and the sequence provides insights into the basis of the versatility and intrinsic drug resistance of P. aeruginosa. Consistent with its larger genome size and environmental adaptability, P. aeruginosa contains the highest proportion of regulatory genes observed for a bacterial genome and a large number of genes involved in the catabolism, transport and efflux of organic compounds as well as four potential chemotaxis systems. We propose that the size and complexity of the P. aeruginosa genome reflect an evolutionary adaptation permitting it to thrive in diverse environments and resist the effects of a variety of antimicrobial substances.