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Porous FePt microcapsules are fabricated for use in bead-based immunoassay technologies, that generally use magnetic spheres to immobilize biomolecules on their surface. The magnetic capsules can be used to carry assay reagents to reduce the time required to perform immunoassay processes, and microsize capsules are easier to manipulate magnetically than nanosize ones. Silica particles of approximately 2.5 μm diameter are used as templates and modified with poly(ethyleneimine) (PEI), which enables FePt nanoparticles to accumulate selectively on the template particles and an FePt shell to be formed by a polyol process. To increase the mechanical stability of the FePt nanoparticle assembly shell, a double-layered FePt nanoparticle assembly is fabricated by repeating the modification process of PEI and the synthesis process of FePt nanoparticles, resulting in the fabrication of magnetic capsules with a three-dimensional structure. We further investigate the ability of magnetic capsules to immobilize antibodies on their surface. Gold nanoparticles are used as linkers between the magnetic microcapsules and antibodies. The antibodies are successfully immobilized on the surface of the developed microsize FePt capsules.

In the elucidation of brain functions, neuroscience has garnered attention in the realization of brain-machine interfaces, deep brain stimulation, and artificial intelligence. Optogenetics is a biological technique used to control neural activities via optical stimulation. It is one of the most effective approaches used to investigate brain functions. This study proposed to employ the transparent recording electrode to enhance the performance of neural probes for optogenetics. Compared with conventional metal recording electrodes, the proposed transparent recording electrodes have the potential to obtain higher signal-to-noise ratios when placed over optical stimulation points. To develop transparent recording electrodes, we used ZnO-based materials with good biocompatibility and transparency for utilization as biomedical electrodes. Considering saline as one of the main components of living organisms, we investigated the fundamental electrochemical characteristics of ZnO-based electrodes in saline through electrochemical impedance spectroscopy and cyclic voltammetry. The results showed that nondoped ZnO and Al-doped ZnO, deposited by radio frequency magnetron sputtering, exhibited a broad potential window. An electrical double layer was found to strongly act on the interface between the electrodes and solution rather than a redox reaction. In addition, this study reports the effects of crystallization and dopant on the electrochemical characteristics of the ZnO-based electrodes. The transparent ZnO-based electrode developed herein is a promising candidate to enhance the performance of neural probes for optogenetics and can be effectively applied in biological devices.

High-density interconnections are highly required for 3D IC such as FPGA and image sensor applications. Fine-pitch interconnects using conventional solder microbumps are still required. To meet this requirements, low-height Cu/Sn microbumps are evaluated in this study. The thermal compression bonding with the low-height solder microbumps makes it challenging to fulfill high-viscous capillary underfill (CUF) into extremely small gaps between the chips stacked in layers. Here, we demonstrate to apply a 7-μm-thick non-conductive film (NCF) to flip-chip bonding with the low-height solder microbumps. Compared with a CUF, the electrical characterization such as electromigration (EM) and leakage current of microbump daisy chains with the ultra-thin NCF was investigated with temperature cycle test (TCT) and unbiased HAST.

A new flexible hybrid electronics (FHE) methodology using advanced RDL-first fan-out wafer-level packaging (FOWLP) technologies with dielets and hydrogel substrates is proposed. Hydrogels mainly consisting of water have excellent biocompatibility, high adaptability, and substance permeability, and they are expected for biomedical applications. In this work, we integrate Si LSI and mini-LED dielets in a hydrogel substrate on which fine-feature Au interconnections are formed in wafer-level processing. We characterize their electrical properties of the embedded dielets for biomedical applications.

This paper deals with multichip-to-wafer (MC2W) 3D stacking technologies based on via-last TSV integration. In this work, we verify the effectiveness of room-temperature CVD named OER (Ozone-Ethylene Radical generation)-TEOS-CVD® to deposit a TSV liner SiO 2 layer. The film quality including dielectric constants is evaluated alternative to plasma-enhanced (PE)-TEOS-CVD SiO 2 . In addition, solid-solid inter-diffusion bonding of 3-μm-thick Sn with 0.5-μm-thick Au is demonstrated to achieve multiple multichip bonding for retinal prosthesis system fabrication with a 3D artificial retina chip. Low-temperature bonding at 190°C is realized by the Au/Sn metallurgy. Good bondability is also obtained with the Au electrodes preliminarily exposed at high temperature. There are no Sn microbump extrusion, which is highly expected to be used for 3D-ICs with fine-pitch solder microbump interconnection.

Through-silicon vias (TSVs) is one of the key technologies for 3D integration. To solve the issues induced by the high-temperature process for TSV liner formation in the multichip-to-wafer (MCtW) process, we applied the low-temperature SiO 2 deposition method called OER (Ozone-Ethylene Radical generation)-TEOS-CVD®. In this study, we fabricated the MIS capacitors with the TSV liner deposited by OER-TEOS-CVD® at 150°C and room temperature (RT), and compared both the coverage and electrical characteristics with that formed by conventional plasma-enhanced chemical vapor deposition (PE-CVD) at 200°C. Furthermore, we analyzed these SiO 2 liners by FTIR and synchrotron XPS. These results showed that the OER-TEOS-CVD® has high potentials to realize highly-reliable TSVs and to apply to various processes in 3D integration.

Impact of temporary bonding conditions and temporary adhesive properties on mechanical stresses in multichip thinning is evaluated for high-yield multichip-to-wafer (MC2W) heterogeneous 3D integration. It turned out that no sidewall covering of chips with a temporary adhesive gives low mechanical stress to the chip edge, leading to less chipping and cracking.

CASE: A 78-year-old woman with rheumatoid arthritis and a massive rotator cuff tear of the right shoulder was treated with reverse shoulder arthroplasty, but a pseudoaneurysm in the posterior humeral circumflex artery suddenly ruptured 7 months after surgery. Embolization of the pseudoaneurysm and skin treatment successfully relieved her symptoms without implant removal. CONCLUSION: Although a rare occurrence, vascular complication can occur after shoulder arthroplasty. The cause of the pseudoaneurysm was hypothesized to be repetitive contact between the humeral component and the artery and/or chronic traction of the blood vessel because of its chronic onset.

PZT films with (1 0 0) and (1 1 0) orientation were prepared by spin coating using the chemical solution deposition (CSD) method on an SRO/Si or a Pt/Ti/SiO 2 /Si substrate. The remnant polarization and the saturation polarization of the PZT/SRO/Si film were 21 and 35 μC/cm 2 , and those of the PZT/Pt/Ti/SiO 2 /Si film were 20 and 31 μC/cm 2 . The remnant polarization of the PZT/SRO/Si film maintained more than 10 8 switching cycles, and the fatigue property was observed for the PZT film fabricated on the Pt/Ti/SiO 2 /Si electrode.

This paper describes the deposition of PZT/lanthanum nickel oxide (LNO) electrode thin-film capacitor on a Si(1 0 0) substrate with a chemical solution deposition (CSD). Highly (1 0 0)-oriented LNO film with a perovskite structure was deposited by annealing at 700 °C from a precursor solution of La(NO 3 ) 3 and Ni(CH 3 COO) 2 . In addition, highly (1 0 0)&(0 0 1)-oriented PZT/LNO capacitor was deposited on LNO/Si substrate by annealing at 600 °C, showing P r = 18 μC/cm 2 and E c = 36 kV/cm. Furthermore, the resultant PZT/LNO thin-film capacitor exhibited no fatigue up to 10 8 switching cycles.

The conductive metal oxide of SrRuO 3 (SRO) thin films were deposited on Si(1 0 0) substrate by spin-coating with a chemical solution deposition (CSD). A stable precursor solution could be prepared from RuCl 3 ·2H 2 O as a Ru source and Sr or SrCl 2 as a Sr source in 2-methoxyethanol. Highly (2 0 0)-oriented SRO films with a perovskite structure were obtained by the annealing at above 600 °C. As a result, relatively good SRO thin films could be deposited from a precursor solution of Sr and RuCl 3 ·2H 2 O by annealing at 700 °C, showing a low resistivity of 1.1×10 −3 Ω cm.

LaNiO 3 (LNO) thin films were prepared onto Si substrate by chemical solution deposition. The orientation of the LNO films was controlled by changing concentration of precursor solution. The resistivity of the resultant LNO films was 1.82 – 2.57×10 −3 Ωcm. The obtained 0.3 M-LNO film was flat surface, highly (100) orientation, and had a low resistivity of 1.85×10 −3 Ωcm. PbZr 0.53 Ti 0.47 O 3 was fabricated onto the resultant 0.3 M-LNO electrode, and the sample showed a good ferroelectric property.