Ion Sputtering Research Articles

Effects of translation misalignment on ion optics with slit apertures

For ion thrusters, the deflection of the ion beam caused by the relative translation of the grids is one of the primary factors limiting the erosion lifetime of the ion optical system. A two-dimensional (2D) simulation package of the ion optic system is developed to investigate the ion sputtering corrosion due to grid translation misalignment. For benchmark cases, the 2D simulation package shows a reasonable consistency compared to the experimental method in ion beam deflection angle and drain-to-beam current ratio, indicating the effectiveness of the simulation package. The deviation between the simulated deflection angle and the experimental value is within 8.86%. Furthermore, this 2D package is employed to analyze the variation patterns of ion beam, ion collection, and the distribution of ion sputtering rates caused by grid translation. The simulation results indicate that the ion beam deflection occurs in the direction opposite to grid translation. The number of ions collected at different positions on the acceleration grid shows different tendencies. Only the upstream surface Sy− and the aperture surface Sx+ will be subjected to energetic ion impingement. The sputtering of energetic ions on these two surfaces becomes the dominant factor limiting the grid’s ion corrosion lifetime when the grid translation is significant. The sputtering rate of energetic ions can exceed that of charge exchange (CEX) ions by more than 10 times. The proportion of the region where energetic ions contribute to sputtering expands with increasing grid misalignment, reaching up to 52.5% on surface Sx+. Additionally, the downstream surface Sy+ and the aperture surface Sx− are only subjected to CEX ion sputtering regardless of grid translation. Moreover, the CEX ion sputtering regions on surfaces Sx− and Sx+ expand as the grid misalignment distance increases. The peak in the ion sputtering rate distribution profile on surface Sy+ becomes more prominent due to grid translation, with the sputtering rate at the peak position reaching approximately 1.65 times that of the surrounding lower-rate regions. The analysis of the electric field indicates that local electric field variations caused by grid misalignment are the underlying reason for the ion erosion characteristics.

The Neutral Water Torus of Europa

AbstractThe neutral particles that escape Europa form a neutral torus which asymmetrically encircles the giant planet Jupiter. The study of this structure can inform on neutral escape at the icy moon and on the loading of the Jovian magnetosphere with Europan material. In this letter, we present the first Monte Carlo model of the neutral water torus of Europa. Water molecules are released to high altitude by ion sputtering of the surface and get dissociated and ionized mostly by electron impact. We find that the density of H2O molecules can be as large as atomic O in a large region of the Jovian magnetosphere. The neutral torus of Europa may therefore have a more diverse composition than previously thought. Plasma instrumentation able to separate H2O+ from O+ pick‐up ions could help to advance our understanding of the neutral torus of Europa.

Unimolecular processes in diatomic carbon anions at high rotational excitation

On the millisecond to second time scale, stored beams of diatomic carbon anions C2− from a sputter ion source feature unimolecular decay of yet unexplained origin by electron emission and fragmentation. To account for the magnitude and time dependence of the experimental rates, levels with high rotational and vibrational excitation are modeled for the lowest electronic states of C2−, also including the lowest quartet potential. Energies, spontaneous radiative decay rates (including spin-forbidden quartet-level decay), and tunneling dissociation rates are determined for a large number of highly excited C2− levels and their population in sputter-type ion sources is considered. For the quartet levels, the stability against autodetachment is addressed and recently calculated rates of rotationally assisted autodetachment are applied. Nonadiabatic vibrational autodetachment rates of high vibrational levels in the doublet C2− ground potential are also calculated. The results are combined to model the experimental unimolecular decay signals. Comparison of the modeled to the experimental rates measured at the cryogenic storage ring facility CSR gives strong evidence that C2− ions in quasistable levels of the quartet electronic states are the so far unidentified source of unimolecular decay. Published by the American Physical Society 2024

Morphology and Magnetic Properties of Ni Nanowires in Thin Film Anodic Alumina Templates

The features of the morphology and magnetic properties of Ni nanowire arrays have been studied. Aluminum oxide matrices are used as a template for electrolytic deposition of nanowires. The matrices are obtained by anodizing the aluminum films with a thickness of 2 μm that are formed on glass substrates by high frequency ion sputtering. Electrochemical deposition of the metal is carried out using direct and alternating currents. Morphology and microstructure studies show that the nanowire arrays are polycrystalline and have a branched dendritic structure due to the morphological features of aluminum oxide matrices. A relationship between the magnetization reversal patterns and the modes of electrodeposition of Ni nanowire arrays is established. The process of magnetization reversal of an array of this kind of structures is simulated.

Characterisation of surface morphology of high voltage DC relay contacts under arc erosion

Abstract High voltage DC relays are a crucial component in new energy vehicles. Due to the high failure rate caused by contact sticking (fusion welding), existing technologies can only analyze contact morphology after failure. There is an urgent need to determine the quantitative characterization value of contact surface morphology and the correlation between morphology, failure mechanisms, and working conditions. In this study, an Olympus DSX1000 microscope is used to extract surface topography data, and a quantitative topography characterization method based on a machine vision system is proposed to quantitatively analyze contact surface changes after arc erosion. Grey correlation analysis was applied to explore the relationship between electrical parameters such as voltage, current, and capacitance, and the contact morphology features. The results show that current and capacitance have the greatest influence on contact surface features after arc erosion, while voltage has a relatively smaller influence. This conclusion is consistent with the experimentally observed arc erosion features. Finally, an arc ion sputtering deposition model was developed to analyze the material transfer mode and its influence on the contact failure mechanism. The results provide a scientific basis for the analysis and design improvement of high voltage DC relays.

MONOCRYSTALLINE DIAMOND MEMBRANES WITH A THICKNESS OF 10 MICRONS, MANUFACTURED BY PLASMA ETCHING

New applications of high-quality synthetic diamond in sensors and integrated photonic circuits, which are being rapidly developed nowdays, often demand freestanding diamond membranes with a thickness of about 10 microns as a substrate. However, the process of thin single-crystal diamond membranes fabrication, as well as their subsequent processing are challenging due to the high hardness, chemical resistance and brittleness of the material. Our work demonstrates a method for creating freestanding diamond membranes mounted on a thick diamond substrate using reactive ion etching of single-crystalline diamond wafers in plasma with mechanical protective masks. The optimal thickness of a diamond wafer for membranes etching is determined in the range from 100 to 120 µm with mandatory plane-parallel polishing of the sides. We experimentally studied the interaction of RF discharge SF6 based plasma with diamond surface during deep etching with mechanical protective masks of various shapes. It was found that the use of thick masks leads to an uneven rate of diamond etching over the entire area of the formed membrane. We have assessed ion sputtering resistance of various mask materials in SF6 based plasma, and found the most promising mask materials for deep diamond etching (steel, copper, diamond). We have fabricated diamond membranes with a thickness of 11,5 µm (and more), mounted on a durable 60 µm (and more) thick frames, and studied their characteristics. After etching membrane surface roughness was less than 25 nm, and the unevenness of their thickness did not exceed 20%. Also, we compare different methods for controlling the depth of diamond etching and the thickness of the resulting membranes, including mechanical measurements, IR spectral reflectometry, optical profilometry and electron microscopy. For citation: Golovanov A.V., Yun M.I., Bondarenko M.G., Prosin A.A., Tarelkin S.A. Monocrystalline diamond membranes with a thickness of 10 microns, manufactured by plasma etching. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 10. P. 55-64. DOI: 10.6060/ivkkt.20246710.1y.

Zinc-tin binary alloy interphase for zinc metal batteries

Aqueous zinc ion batteries are rapidly developing as the most propitious energy storage system due to their high security, high specific capacity and low cost, etc. However, zinc anodes suffered from dendrite growth and hydrogen evolution reactions during cycling, so it is of utmost importance to upgrade zinc anode properties. In this study, the homogeneous layer of ZnSn alloy interphase was formed by introducing metallic tin to the anode surface using an ion sputtering technique. ZnSn alloy can reduce the hydrogen evolution over-potential of anode and the corrosion current, inhibiting the occurrence of hydrogen evolution and corrosion reaction. Moreover, the ZnSn alloy anode can provide uniform nucleation sites and uniformize the electric field on the anode surface, promote the uniform deposition of Zn2+, thus inhibiting the formation of zinc dendrites. Notably, compared to the Zn foil//Zn foil cell (400 h), the ZnSn alloy symmetric cell showed excellent cycling performance by cycling for 1000 h at 0.5 mA cm−2. Furthermore, even at current density of 1 A/g, the capacity retention of the ZnSn alloy//MnO2 full cell was up to 89.5 % compared to only 32.3 % for Zn foil//MnO2 cell. The preparation of this ZnSn alloy anode may provide new ideas for future alloying strategies.

Interfacial modification of CuO/Ga2O3 by plasmonic Pt for high performance self-powered solar-blind UV photodetector

Applications for solar-blind photodetectors (PDs) vary widely and include space communications, ozone monitoring, and more. In this study, pulsed laser deposition (PLD) and ion sputtering were employed to develop an unusual self-powered deep ultraviolet (UV) photodetector based on CuO/Ga2O3 with a Pt nanoparticles (NPs) interface. The Pt NPs interface transforms the device design from heterojunction to Schottky junction. The device features a low dark current of 83.2 fA and performs a high photo-to-dark current (Iphoto/Idark) ratio of 1.72 × 104, a specific detectivity (D*) of 9.98 × 1011 Jones, and a quick decay time of 56 ms upon 254 nm UV light at 196.5 μW/cm2 without any power supply. The CuO/Pt/Ga2O3 Schottky junction-based device outperforms the CuO/Ga2O3 heterojunction-based device in terms of detection capabilities in both biased and non-biased settings. This is explained by the Schottky barrier creation mechanism with both Ga2O3 and CuO films, as well as how the plasmon resonance effect (PR effect) balances the barrier on the Ga2O3 side. Furthermore, Pt NPs serve as a potential well, offering an additional recombination channel that accelerates the decay process when the light is turned off. Our findings pave the way for more optoelectronic uses of Ga2O3-based solar-blind UV photodetectors in the future.

Preparation and Biochemical Activity of Copper-Coated Cellulose Nonwoven Fabric via Magnetron Sputtering and Alginate-Calcium Ion Complexation.

Alginate-based materials have gained significant recognition in the medical industry due to their favorable biochemical properties. As a continuation of our previous studies, we have introduced a new composite consisting of cellulose nonwoven fabric charged with a metallic copper core (CNW-Cu0) covered with a calcium alginate (ALG-Ca2+) layer. The preparation process for these materials involved three main steps: coating the cellulose nonwoven fabric with copper via magnetron sputtering (CNW → CNW-Cu0), subsequent deposition with sodium alginate (CNW-Cu0 → CNW-Cu0/ALG-Na+), followed by cross-linking the alginate chains with calcium ions (CNW-Cu0/ALG-Na+ → CNW-Cu0/ALG-Ca2+). The primary objective of the work was to supply these composites with such biological attributes as antibacterial and hemostatic activity. Namely, equipping the antibacterial materials (copper action on representative Gram-positive and Gram-negative bacteria and fungal strains) with induction of blood plasma clotting processes (activated partial thromboplastin time (aPTT) and prothrombin time (PT)). We determined the effect of CNW-Cu0/ALG-Ca2+ materials on the viability of Peripheral blood mononuclear (PBM) cells. Moreover, we studied the interactions of CNW-Cu0/ALG-Ca2+ materials with DNA using the relaxation plasmid assay. However, results showed CNW-Cu0/ALG-Ca2+'s cytotoxic properties against PBM cells in a time-dependent manner. Furthermore, the CNW-Cu0/ALG-Ca2+ composite exhibited the potential to interact directly with DNA. The results demonstrated that the CNW-Cu0/ALG-Ca2+ composites synthesized show promising potential for wound dressing applications.

XPS Investigation of Co-Ni Oxidized Compounds Surface Using Peak-On-Satellite Ratio. Application to Co20Ni80 Passive Layer Structure and Composition.

XPS data processing for cobalt and nickel core-level peaks can be complicated. This is especially true when analyzing a mixture of oxide/oxyhydroxide/hydroxide compounds of these metals. The objective of this study is to develop a method for decomposing XPS spectra of 2p core levels for nickel and cobalt-oxidized compounds. This methodology was then employed to study the passivation layer of the Co20Ni80 alloy. The analysis of Ni2p and Co2p photo peaks using a homemade code based on core-level peak structure and satellites enables us to determine the chemical composition of the surface layer, knowledge of which is particularly important because it is directly linked to the anticorrosive properties it confers on the surface of the oxidized alloy. The XPS analysis, coupled with sequential ion sputtering, revealed that the passive layer of the Co20Ni80 alloy is heterogeneously covered with either oxidized cobalt compounds or oxidized nickel compounds. The method used also demonstrates that the chemical heterogeneity is associated with the thickness heterogeneity of the passive layer.

Integrated Amorphous Carbon Film Temperature Sensor with Silicon Accelerometer into MEMS Sensor.

Amorphous carbon (a-C) has promising potential for temperature sensing due to its outstanding properties. In this work, an a-C thin film temperature sensor integrated with the MEMS silicon accelerometer was proposed, and a-C film was deposited on the fixed frame of the accelerometer chip. The a-C film was deposited by DC magnetron sputtering and linear ion beam, respectively. The nanostructures of two types of films were observed by SEM and TEM. The cluster size of sp2 was analyzed by Raman, and the content of sp2 and sp3 of the carbon film was analyzed by XPS. It showed that the DC-sputtered amorphous carbon film, which had a higher sp2 content, had better temperature-sensitive properties. Then, an integrated sensor chip was designed, and the structure of the accelerometer was simulated and optimized to determine the final sizes. The temperature sensor module had a sensitivity of 1.62 mV/°C at the input voltage of 5 V with a linearity of 0.9958 in the temperature range of 20~150 °C. The sensitivity of the sensor is slightly higher than that of traditional metal film temperature sensors. The accelerometer module had a sensitivity of 1.4 mV/g/5 V, a nonlinearity of 0.38%, a repeatability of 1.56%, a total thermomechanical noise of 509 μg over the range of 1 to 20 Hz, and an average thermomechanical noise density of 116 µg/√Hz, which is smaller than the input acceleration amplitude for testing sensitivity. Under different temperatures, the performance of the accelerometer was tested. This research provided significant insights into the convenient procedure to develop a high-performance, economical temperature-accelerometer-integrated MEMS sensor.

Decipher the Wavelength and Intensity Using Photothermoelectric Detectors.

Broadband photodetectors that can decipher the wavelength (λ) and intensity (I) of an unknown incident light are urgently demanded. Photothermoelectric (PTE) detectors can achieve ultrabroadband photodetection surpassing the bandgap limitation; however, their practical application is severely hampered by the lack of deciphering strategy. In this work, we report a variable elimination method to decipher λ and I of the incident lights based on an integrated Ag2Se film-based PTE detector. Nanostructured Ag2Se films with controlled thickness are synthesized using an ion sputtering of Ag and a room-temperature selenization method and then assembled into a detector. Under identical illumination, Ag2Se films of different thicknesses produce varying output photothermal voltages, influenced by factors including λ. By establishing a direct relationship between the photothermal voltage and the absorption of Ag2Se films of varied thickness, we successfully eliminate variables independent of λ, thus determining λ. Subsequently, I is determined by the calibrated responsivity relationship using obtained λ. Our PTE detector achieves a broadband spectrum from 400 to 950 nm and high accuracy, with deviations as low as ∼2.63 and ∼0.53% for deciphered λ and I, respectively. This method allows for self-powered broadband decipherable photodetection without a complex device architecture or computational assistance, which could boost the research enthusiasm and promote the commercialization of PTE broadband detectors.

Controllable Fabrication of Gallium Ion Beam on Quartz Nanogrooves.

Nanogrooves with high aspect ratios possess small size effects and high-precision optical control capabilities, as well as high specific surface area and catalytic performance, demonstrating significant application value in the fields of optics, semiconductor processes, and biosensing. However, existing manufacturing methods face issues such as complexity, high costs, low efficiency, and low precision, especially in the difficulty of fabricating nanogrooves with high resolution on the nanoscale. This study proposes a method based on focused ion beam technology and a layer-by-layer etching process, successfully preparing V-shaped and rectangular nanogrooves on a silicon dioxide substrate. Combining with cellular automaton algorithm, the ion sputtering flux and redeposition model was simulated. By converting three-dimensional grooves to discrete rectangular slices through a continuous etching process and utilizing the sputtering and redeposition effects of gallium ion beams, high-aspect-ratio V-shaped grooves with up to 9.6:1 and rectangular grooves with nearly vertical sidewalls were achieved. In addition, the morphology and composition of the V-shaped groove sidewall were analyzed in detail using transmission electron microscopy (TEM) and tomography techniques. The influence of the etching process parameters (ion current, dwell time, scan times, and pixel overlap ratio) on groove size was analyzed, and the optimized process parameters were obtained.

Multicoated Flexible Indium Tin Oxide Electrodes Fabricated Using Magnetron Sputtering and Arc Plasma Ion Plating for Flexible Perovskite Solar Cells.

High-performance flexible Sn-doped In2O3 (indium tin oxide, ITO) electrodes were fabricated using a multicoating process on colorless polyimide (CPI) substrates for flexible perovskite solar cells (FPSCs). The effects of different coating sequences on the electrical, optical, and mechanical properties of the flexible ITO electrodes were thoroughly investigated after preparing them with direct-current magnetron sputtering (DMS) and arc plasma ion plating (APIP). Although both the sputtered ITO (SITO)/arc ion-plated ITO (AITO) film and the AITO/SITO film showed similarly low sheet resistance (18.69-25.29 Ω/sq) and high optical transmittance (94.96-96.85%), the coating sequence significantly affected the mechanical flexibility of the multicoated ITO films. The 120 nm-thick SITO/AITO electrode exhibited small outer and inner critical bending radii (3 mm and 3 mm, respectively) compared to the AITO/SITO electrode (4 and 5 mm, respectively). Owing to better adhesion of the arc-ion-plated ITO bottom layer and the amorphous structure of the top SITO layer, the SITO/AITO electrode exhibited excellent mechanical flexibility and durability. In addition, an FPSC using the SITO/AITO electrode achieved a higher power conversion efficiency (15.09%) than that with the AITO/SITO electrode (13.22%). This improvement was attributed to its high transmittance, low sheet resistance, smooth surface morphology, and enhanced hole collection efficiency. These findings highlight the efficacy of the combined DMS and APIP multicoating process for fabricating high-quality flexible ITO electrodes for high-performance FPSCs.

How Bulk Versus Surface Chemistry Affects the Surface Reconstruction of Perovskite Nickelates and Their Activation By Fe Impurities

Whether surface reconstruction of LaNiO3 and the related Ruddlesden-Popper oxide La2NiO4 occurs during the oxygen evolution reaction has only recently emerged as a topic of rigorous study despite the implications this would have for its activity and stability at scales from the three-electrode cell to electrolyzer stacks. Correlation of structure to reconstruction propensity is much needed, but not well-understood. Building off of our work suggesting that these oxides do electrochemically reconstruct to the thermodynamically stable, amorphous, Fe impurity-sensitive, nickel hydroxide, we extend our observations to materials doped with alternative rare earth and alkaline earth metal cations at the La-site. First, we find that undoped La2NiO4 has a higher tendency to reconstruct, forming almost twice as much Ni(OH)2 for a given electrochemical treatment as LaNiO3 which we attribute to differences in Ni valence state between the two materials. This leads to a higher current density when exposed to Fe impurities by formation of more NiFeOxHy, the highest activity catalyst for OER known. Yet, the intrinsic activity of the Fe sites formed are equivalent within experimental error suggesting a convergence in surface composition despite different bulk composition. We find this reconstruction also occurs for doped materials, extending the library of materials expected to have dynamic surfaces during OER. Further, we use XPS coupled with argon ion sputtering to connect differences in reconstruction extent to the bulk and surface composition, with particular emphasis on the valence state of nickel as a possible descriptor.

High Broadband Optical Absorption and Bandstop Filter Characteristics of Pb/Nb2O5 Interfaces

AbstractIn this study, semitransparent lead films serve as substrates for depositing niobium pentoxide thin films, forming versatile electro‐optical devices. Using vacuum evaporation and ion sputtering techniques at ≈10−5 mbar, stacked layers of crystalline Pb and amorphous Nb2O5 are created. This process reduces free carrier absorption in Nb2O5 and forms Urbach tail states with a width of 0.91 eV. Pb/Nb2O5 thin films exhibit remarkable broadband absorption, exceeding 440% in the visible and 98% in the infrared. Moreover, Pb substrates induce a redshift in Nb2O5’s energy bandgap. Electrical analysis using impedance spectroscopy on Pb/Nb2O5/Ag structures reveals their series/parallel resonance and bandstop filter properties. Notably, the bandstop filters exhibit reflection coefficient minima at a notch frequency of 1.66 GHz, with a bandwidth of 280 MHz, return loss of 26 dB, and voltage standing wave ratio of 1.13. These findings underscore the device's potential for wide‐ranging electro‐optical applications across the electromagnetic spectrum.

Lunar soil record of atmosphere loss over eons.

The Moon has a tenuous atmosphere produced by space weathering. The short-lived nature of the atoms surrounding the Moon necessitates continuous replenishment from lunar regolith through mechanisms such as micrometeorite impacts, ion sputtering, and photon-stimulated desorption. Despite advances, previous remote sensing and space mission data have not conclusively disentangled the contributions of these processes. Using high-precision potassium (K) and rubidium (Rb) isotopic analyses of lunar soils from the Apollo missions, our study sheds light on the lunar surface-atmosphere evolution over billions of years. The observed correlation between K and Rb isotopic ratios (δ 87Rb = 0.17 δ 41K) indicates that, over long timescales, micrometeorite impact vaporization is the primary source of atoms in the lunar atmosphere.

Cryogen-free modular scanning tunneling microscope operating at 4-K in high magnetic field on a compact ultra-high vacuum platform.

One of the daunting challenges in modern low temperature scanning tunneling microscopy (STM) is the difficulty of combining atomic resolution with cryogen-free cooling. Further functionality needs, such as ultra-high vacuum (UHV), high magnetic field (HF), and compatibility with μm-sized samples, pose additional challenges to an already ambitious build. We present the design, construction, and performance of a cryogen-free, UHV, low temperature, and high magnetic field system for modular STM operation. An internal vibration isolator reduces vibrations in this system, allowing for atomic resolution STM imaging while maintaining a low base temperature of ∼4K and magnetic fields up to 9T. Samples and tips can be conditioned in situ utilizing a heating stage, an ion sputtering gun, an e-beam evaporator, a tip treater, and sample exfoliation. In situ sample and tip exchange and alignment are performed in a connected UHV room temperature stage with optical access. Multisite operation without breaking vacuum is enabled by a unique quick-connect STM head design. A novel low-profile vertical transfer mechanism permits transferring the STM between room temperature and the low temperature cryostat.

Reactive ion etching of indium gallium zinc oxide (IGZO) and chamber cleaning using low global warming potential gas

Indium gallium zinc oxide (IGZO) is attracting increasing attention as a promising semiconducting material for use in next-generation semiconductors and display devices; for the application of IGZO to next-generation devices, it is necessary to have dry etch characteristics such as highly anisotropic etch profile, fast etch rate, and high mask selectivity. In the present study, IGZO was etched with various hydrofluorocarbon (HFC)-type gases (CxHyFz) in an inductively coupled plasma (ICP) etcher and, the etch characteristics and the possibility of removing the residue forming on the chamber wall by in-situ chamber cleaning was investigated. This study also investigated the use of low global warming potential (GWP) gas in IGZO etching, in response to the fact that HFC-type gases tend to show high GWP. The results showed that, when HFC-type gases were used in the etching of IGZO, the ratio of H/F in HFC affected the IGZO etch rate and etch selectivity. Among the HFC gases used in the experiment, such as CHxFy (x + y = 4) and C3HxFy (x + y = 8), IGZO was etched faster with the gas with higher H/F ratio, which was attributed to the easier removal of zinc in IGZO during the etching, along with the removal of In through the formation of more volatile In(CHx)y; this is attributed to the fact that, among IGZO components, zinc was the most difficult material to etch with the HFC gases. Among the HFC-type gases investigated, C3H6F2 (HFC-272ca), which is a low GWP (GWP100yr = 139) gas, showed the highest etch rate of ∼ 55 nm/min, the lowest dimensional loss (less than 7 nm for photoresist masked IGZO), and the most anisotropic etch profile with the lowest surface roughness. During the etching with HFC gases, compounds such as GaHx/Ga(CHx)y, COx, In(CHx)y, and Zn(CHxFy)z were expected to have been produced as byproducts, and these were removed through Ar+ ion sputtering from the IGZO surface, but some of the these compounds were accumulated on the chamber wall along with dissociated HFCs that were formed during the etching. However, it was possible to completely remove these etch byproducts that had been formed on the chamber wall by using a H2/Ar plasma.

Silk fibroin wetting stability film induced by polyamide-amine-epichlorohydrin (PAE) for intelligent sensing system

Protein materials gain new functions and applicability through redesigns in protein structure and engineering confer. However, the application and development of proteins for use in flexible devices that fit in flexible devices that fit the surface of human skin is hindered by their poor wet stability. Here, we described the design of wet-stable materials based on the reconstruction of silk fibroin (SF). The combination of polyamide-amine-epichlorohydrin (PAE) was used as a traction rope to bring SF molecular chains closer to each other, to facilitate the self-assembly of SF through branching and lengthening of molecular chains, and change its crystalline structure. SF/PAE composite films that exhibited huge improvement in ductility and wet stability were combined with flexible SF substrates via patterning and ion sputtering to prepare flexible sensors. In addition, the SF/PAE sensing system equipped with a microprocessor and Bluetooth module enabled the real-time remote acquisition of human health signals such as vocal cords, joints, pulse and meridians. This reconfiguration of the SF structure will advance the systematic exploration of protein structures and the development of protein materials for intelligent device applications.