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This article focuses on recent studies of the development of bioinspired supramolecular materials mimicking the contact events seen at the dynamic bio-interfaces. A diverse range of cellular activities occurs through the dynamic actions of biomacromolecules and supramolecular assemblies such as extracellular matrices, phospholipid bilayers, and membrane proteins that construct the interfaces between and within cells. Mimicking their dynamic actions seen at the bio-interfaces can be an effective approach to developing biomaterials applicable to regenerative medicine and drug delivery systems. Rapid progress in supramolecular chemistry and nanotechnology has made it possible to construct and functionalize various bio-interfaces with dynamic natures. In this article, the construction of artificial extracellular matrices and membrane-deforming supramolecular materials is highlighted with their applications to injured brain regeneration and in vivo cargo delivery for extended blood circulation.

Since the cellular process of endocytosis enables uptake of biomacromolecules interacting with the cell surface by outside-in vesicle fission, endocytosis-like membrane deformation is an ideal methodology for the incorporation of micrometer-size biomacromolecules into vesicles. However, such endocytosis-like vesicle fission, which requires expansion of the liposomal membrane, has never been realized using artificial liposomal systems. Here, we developed a membrane-expanding molecular machine containing a diazocine core (AzoMEx), which exhibits an opening/closing mechanical motion in response to visible light. Upon blue light irradiation, AzoMEx embedded in a 1,2-dioleoyl-sn-glycero-3-phosphocholine bilayer expanded the liposomal membrane, assembled, and eventually induced outside-in endocytosis-like fission. When this vesicle fission was induced in the presence of micrometer-size M13 phage, it was efficiently incorporated into the vesicle by interacting with AzoMEx. The encapsulated M13 phage was transiently protected from the external environment, retaining its biological activity, and thus could be distributed throughout the body after blood administration.

A cholic acid-appended peptide with a metal-binding capability stabilized a phospholipid-based bicelle. The supramolecularly stabilized bicelle showed extended blood circulation compared with spherical liposomes.

Manganese dioxide (MnO2) is widely used in cosmetics and self-cleaning materials because of the high refractive index and photocatalytic activity of this compound. In the present work, the surfaces of MnO2 particles were coated with a commercially available anionic phospholipid mixture, Technol PG, and sodium cholate(SC). These coated particles were readily dispersed in water and subsequently applied as films onto glass substrates by drop-casting.

During injured tissue regeneration, the extracellular matrix plays a key role in controlling and coordinating various cellular events by binding and releasing secreted proteins in addition to promoting cell adhesion. Herein, we develop a cell-adhesive fiber-forming peptide that mimics the jigsaw-shaped hydrophobic surface in the dovetail-packing motif of glycophorin A as an artificial extracellular matrix for regenerative therapy. We show that the jigsaw-shaped self-assembling peptide forms several-micrometer-long supramolecular nanofibers through a helix-to-strand transition to afford a hydrogel under physiological conditions and disperses homogeneously in the hydrogel. The molecular- and macro-scale supramolecular properties of the jigsaw-shaped self-assembling peptide hydrogel allow efficient incorporation and sustained release of vascular endothelial growth factor, and demonstrate cell transplantation-free regenerative therapeutic effects in a subacute-chronic phase mouse stroke model. This research highlights a therapeutic strategy for injured tissue regeneration using the jigsaw-shaped self-assembling peptide supramolecular hydrogel., The extracellular matrix contributes to tissue regeneration by binding and releasing growth factors. Here the authors present the jigsaw-shaped self-assembling peptide JigSAP as an artificial ECM and show that VEGF-JigSAP has therapeutic effects on the subacute-chronic phase of brain stroke.

Titanium dioxide (TiO2) is widely used in cosmetics and self-cleaning materials because of its high refractive index and photocatalytic activity. In the present work, the surfaces of TiO2 nanoparticles were coated with sodium cholate and the commercially available anionic phospholipid mixture Technol PG. These surface-coated TiO2 nanoparticles could be homogeneously dispersed in water and subsequently produced films on glass substrates after drop casting.

Cannabidiol (CBD) has been used for the treatment of neuronal disease. Herein CBD was mixed with sodium cholate and Technol PG, a commercially available mixture of anionic phospholipids, which allowed for effective dispersion of the CBD in water.

Reduction of electrical resistance of middle-of-line (MOL) is now a primary requirement for advanced CMOS. In this paper, we demonstrate that the cluster-preforming-deposited (CPD) WSin (n ≤ 12) film is a promising contact material for S/D in CMOS; insertion of the WSin film reduces the electron SBH to 0.32 eV at W/n-Si and to 0.43 eV at Co/n-Si junctions. This SBH reduction is due to the fact that the WSin film has a low work function of 4.0 eV and effectively passivates the Si surface without forming an appreciable density of interface states, thereby releasing the Fermi level pinning at the Si surface. These junctions have an excellent stability against annealing up to 700˚C for W/WSin/n-Si and to 500˚C for Co/WSin/n-Si. Furthermore, this film significantly prevents the Cu diffusion with a TDDB barrier height of 1.33 eV under a 5 MV/ cm stress.

Owing to the similarity to biological tissues, soft materials have attracted increasing attention as components of biological tissues. However, there is a large difference between synthetic soft materials and biological tissues. Most synthetic soft materials are structurally isotropic, whereas some biological tissues have anisotropic structures that continue over a macroscopic size scale. As seen in muscle, blood vessels, articular cartilage, and iridophores, such anisotropic structures often play critical roles in producing their superb functions. Thus, the control of “structural anisotropy” is a key concept for the further exploration of functional soft materials science. Using the magnetic orientation of nanoobjects in a colloidal dispersion and subsequent in situ polymerization, we recently succeeded in developing anisotropic soft materials, in which highly oriented structures (order parameter = > 0.95) extend over a macroscopic size scale (~10 cm). In addition, we demonstrated unprecedented unique functions of the resultant materials, including ultralarge mechanical anisotropy similar to articular cartilage, quick and large deformation similar to muscular tissues, and dynamic structural color modulation similar to the skin of tropical fish. Integration of the related studies on soft materials with anisotropically oriented structures would bring the concepts of artificial organs and soft robotics into reality. Magnetic orientation of nanoscopic objects in dispersions and subsequent in situ polymerization produced anisotropic soft materials, in which highly oriented structures (order parameter = > 0.95) extended over a macroscopic size scale (~10 cm). The resultant materials exhibited unprecedented unique functions that are reminiscent of biological tissues, including ultralarge mechanical anisotropy, similar to articular cartilages, quick and large deformation, similar to muscular tissues, and dynamic structural color modulation, similar to the skin of tropical fish.

Advanced channel formation technologies called HEtero-layer-lift-off utilizing SiGe heteroepitaxy have been realized for fabricating ultrathin body (UTB) Ge-on-insulator (GeOI) structures. Insertion of SiGe etching stop layer was found to be effective for reducing GeOI body thickness ( $T_{\mathrm {body}}$ ) fluctuation. Backside Si passivation for Ge/buried oxide interface has been verified to suppress backside Coulomb scattering and help to induce volume inversion effect. With improvement of backside interfacial quality and precise control of GeOI $T_{\mathrm {body}}$ , primary carrier scattering factors in GeOI channel have been effectively reduced, resulting in significant improvement of hole mobility. High hole mobility of ~150 cm2/Vs in UTB GeOI pMOSFETs without strain technology has been demonstrated, which also outperformed Si universal mobility by 1.5 times even under $T_{\mathrm {body}}$ of 9 nm. With low-thermal-budget process compatibility, UTB GeOI platform is very promising for future Ge large-scale integrated circuits devices used in monolithic 3-D integration scheme.

The diagnosis of ocular misalignment is difficult and needs examination by ophthalmologists and orthoptists. However, there are not enough qualified personnel to perform such diagnoses. The eye position check is in part systematized. With this check system, we can detect not only the symptoms but also the angle and the extent of strabismus. However, the types of strabismus that can be detected with this technique are limited to exotropia. The purpose of this study is to develop a simplified check system to screen at least the presence of strabismus apart from the type of strabismus or amount of ocular deviation. First, we digitalized the check process. Specifically, we digitized the elemental technology, i.e., the cover–uncover function, required for automation of the typical cover test for eye position check. Furthermore, we developed and implemented an abnormality determination process and evaluated the performance of the system through this experiment, the results of which indicated a higher detection capability than the conventional cover test performed by ophthalmologists and orthoptists.

Fullerene has attracted much attention for applications in biomaterials because of its high antioxidant activity. In this study, C60 and C70 fullerenes were mixed with a commercially available anionic phospholipid mixture, Technol PG, and sodium cholate, resulting in effective dispersion of the fullerenes to give small-sized fullerene nanoparticles.

In this work, the dispersibility of Technol PG, composed of anionic phospholipids, was investigated in the presence of cholic acid-based surfactants.

A simple method to form ultra-thin (2 and Si3N4. We found that decreasing the Ge thickness reduces the grain size and increases the grain boundary barrier height, causing carrier mobility degradation. We examined two methods, known effective to enhance the grain size in the thicker Ge (>100 nm). As a result, a relatively high Hall hole mobility (59 cm2 V−1 s−1) has been achieved with a 20 nm thick polycrystalline Ge layer on Si3N4, which is the highest value among the previously reported works.

A mixture of 1,2-dipalmitoyl- sn-glycero-3-phosphatidylcholine (DPPC) phospholipid and sodium chelate (SC) formed bicelles (DPPC–SC bicelle) at around 50 °C. In 2H nuclear magnetic resonance (NMR) measurement of the dispersion of DPPC–SC bicelle, quadrupole splitting of D2O, an index of the ability to orient molecules, was observed.

Peptide-based fibrous supramolecular assemblies represent an emerging class of biomaterials that can realize various bioactivities and structures. Recently, a variety of peptide fibers with attractive functions have been designed together with the discovery of many peptide-based self-assembly units. Cross-linking of the peptide fibers is a key strategy to improve the functions of these materials. The cross-linking of peptide fibers forming three-dimensional networks in a dispersion can lead to changes in physical and chemical properties. Hydrogelation is a typical change caused by cross-linking, which makes it applicable to biomaterials such as cell scaffold materials. Cross-linking methods, which have been conventionally developed using water-soluble covalent polymers, are also useful in supramolecular peptide fibers. In the case of peptide fibers, unique cross-linking strategies can be designed by taking advantage of the functions of amino acids. This review focuses on the current progress in the design of cross-linked peptide fibers and their applications.

All-dielectric photonics is a rapidly developing field of optics and material science. The main interest at visible and near-infrared frequencies is light management using high-refractive-index Mie-resonant dielectric particles. Most work in this area of research focuses on exploiting Si-based particles. Here, we study monocrystalline Mie-resonant particles made of Ge-rich SiGe alloys with refractive index higher than that of Si. These islands are formed via solid state dewetting of SiGe flat layers by using two different processes: (i) dewetting of monocrystalline SiGe layers (60%-80% Ge content) obtained via Ge condensation of SiGe on silicon on insulator; and (ii) dewetting of a SiGe layer deposited via molecular beam epitaxy on silicon on insulator and ex situ Ge condensation, forming a Ge-rich shell surrounding a SiGe-core. Using high-spatial-resolution Raman microscopy we monitor Ge content x and strain ϵ of flat layers and SiGe-islands. We observe strain relaxation associated with formation of trading dislocations in the SiGe islands compared to the starting SiGe layers, as confirmed by TEM images. For initial high Ge concentration in the flat layers, the corresponding Ge content in the dewetted islands is lower, owing to diffusion of Si atoms from Si or SiO

In this work, we prepared a transparent dispersion of fullerene nanoparticles by sonication with anionic phospholipids of 1,2-dipalmitoyl-sn-glycero-3-phosphorylglycerol (DPPG) with fluorescently NBD-labeled 1,2-dipalmitoyl-sn-glycero-3-phosphorylethanolamine (DPPE). Upon incubation of the fullerene nanoparticles with a rat skin, the nanoparticles successfully penetrated the stratum corneum and reached the epidermis.

In this work, fullerene was dispersed with anionic phospholipids of 1,2-dipalmitoyl-sn-glycero-3-phosphorylglycerol (DPPG) and small-sized fullerene nanoparticles were successfully prepared.

Mixtures of a phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine, DPPC) and a sodium-cholate-derived surfactant (SC-C5 ) at room temperature formed phospholipid bilayer fragments that were edge-stabilized by SC-C5 : so-called "bicelles". Because the bilayer melting point of DPPC (41 °C) is above room temperature and because SC-C5 has an exceptionally low critical micelle concentration (

In contrast to known Raman-thermometric measurements of thermal conductivity (k) of suspended Si nano-membranes, here we apply Raman thermometry for k measurement of mono- and nano-crystalline Si films on quartz, which is important for applications in thermoelectricity and nanoelectronics. Experimentally, we measure linear dependence of the laser-induced Raman band downshift, which is proportional to the moderate heating ΔT, on the laser power P. Then we convert the downshift to ΔT and determine the ratio ΔT/P. The actual power absorbed by the film is calculated theoretically and controlled experimentally by the reflection/transmission measurement. Then we calculate ΔTcalc/P for arbitrary film k assuming diffusive phonon transport (DPT). Film k is determined from the condition ΔT/P = ΔTcalc/P. We show that this method works well for films with thickness h > Λ, where Λ is phonon-mean-free path, even for low-k films like nano-crystalline Si and SiGe. For h

Silicon growth using chemical vapor deposition (CVD) is omnipresent in electronic device technology. CVD reactions of different precursor molecules on Si have been the focus of research for decades. Renewed interest in the CVD growth of silicon films has been spurred by the need for high-quality, ultrathin films for fabrication of novel electronic devices. In this work, we have formulated an experimental nanoscale approach to analyze the modification of wet-prepared Si(0 0 1) surfaces by dichlorosilane (SiH2Cl2, DCS) reactions at low pressure and 500–650 °C performed in a thermal CVD reactor connected to a scanning tunneling microscopy and spectroscopy (STM/STS) system. The DCS dissociation reaction resulted in a decrease of the Si surface potential due to the creation of chlorine-induced electric dipoles. Employing the ability of the scanning tunneling spectroscopy (STS) to recognize specific adsorption sites, we have carried out a comparative analysis of the relative coverage by Cl and Si as a function of exposure conditions. The existence of an intermediate reaction state of the DCS molecule was confirmed by the STS spectra and further supported by Si XPS data and ab initio calculations. This experimental nanoscale approach shows great promise for the CVD growth of ultrathin films.

This paper describes the use of flash lamp annealing (FLA) to fabricate high-Sn content GeSn n-MOSFETs. We exploit FLA processing for both impurity activation and for the solid-phase growth (SPG) of the GeSn channel. High-Sn incorporation of up to 12% is achieved by overcoming the solid-solubility limit of Sn in Ge (1%), and high-quality n+-source/drain junctions were obtained by P implantation and subsequent FLA. Consequently, we achieved well-behaved transistor operation of the SPG-Ge0.88Sn0.12 n-MOSFETs, with an on/off current ratio one order of magnitude higher than for conventional rapid thermal annealing processing.

We have demonstrated that sub-10 nm-thick heteroepitaxial Ge films on Si (001) having smooth surfaces can be obtained by DC magnetron sputtering. Ge films grown at 350 °C preserve the smooth surfaces with a roughness root mean square (RMS) of 0.39 nm, whereas, the Ge films grown at 500 °C show significant roughness with an island-like morphology. In samples grown at 350 °C, it is confirmed that the Ge films are grown epitaxially by cross-section transmission electron microscopy (TEM) and X-ray diffraction (XRD) rocking curve measurements. Rapid thermal annealing (RTA) at 720 °C is effective in improving the crystalline quality and the degradation in the roughness is negligible. Raman spectra and an XRD reciprocal space map reveal that the epitaxial Ge grown at 350 °C show an in-plane compressive strain and that the strain continues to remain after a 720 °C RTA.

High quality ultrathin body (UTB)-Ge-on-insulator (GeOI) substrates have been fabricated with advanced layer transfer technology called HEtero-Layer-Lift-Off. With precise control of interfacial qualities, Ge crystallinity and thickness fluctuation in GeOI substrates, electron mobility of UTB-GeOI nMOSFETs with body thickness ( $T_{\text {body}}$ ) from 20 to 3 nm has been systematically investigated. A significant electron mobility enhancement as $T_{\text {body}}$ scaling below 13 nm has been observed. This newly found mobility enhancement induced by channel thickness scaling could be attributed to the modulation of energy band structure in (001) confined UTB GeOI, where electron effective mass reduction is predicted by first-principle calculation.

The ultra thin body (UTB) SiGe on insulator (SGOI) substrate with body thickness of only 5 nm has been fabricated by hetero-layer transfer technique with highly selective wet etching. According to Raman spectroscopy, UTB-SiGe layer with Ge fraction of 67% and +1% partially tensile strain was transferred onto the SiO2/Si host substrate without the strain degradation. To present the feasibility of UTB-SGOI substrate, a well-behaved performance of 2-μm-gate-length normally off UTB-SGOI nMOSFET has also been demonstrated.

This work addresses nanoscale measurements of mechanical properties of ultra-thin insulator films by a dynamic indentation atomic force microscopy (DI-AFM). The ability of the DI-AFM is discussed to clarify some challenges in quantitative evaluation of stiffness and elastic modulus of 10 nm films on Ge and S.i.

We demonstrated high-quality single crystal Germanium (Ge) layer transferred on arbitrary substrates, such as Si, glass, and flexible plastic substrates utilizing direct bonding and epitaxial lift-off (ELO) techniques. Owing to Ge epitaxial growth on GaAs substrates with AlAs release layer, we successfully transferred epitaxial Ge layers on arbitrary substrates with a wide range of thickness from several um to $\sim 1$ nm. This layer tranfer approach enables us to realize Ge-based monolithic 3D devices without degradation of Ge crystalline quality.

Backside Si passivation for ultrathin boy (UTB) GeOI has been verified to suppress Coulomb scattering from Ge/buried oxide (BOX) interface. With improvement of backside interfacial quality, primary carrier scattering factors in GeOI channel have been effectively reduced, resulting in significant enhancement of hole mobility. The hole mobility improvement has been proved through device characterizations of UTB GeOI $p$ MOSFETs and Hall measurements. UTB GeOI platform formed by only low thermal budget processes is very promising for future Ge large scale integrated (LSI) circuits devices in monolithic 3D (M3D) integration scheme.