Plasma Chemical Etching Research Articles

Innovative surface engineering of sustainable polymers: Toward green and high-performance materials

The development of sustainable polymers is critical to the progression of greener manufacturing processes, especially for the additive manufacturing technologies of fused deposition modeling (FDM). The study aims to explore potential application surface engineering techniques that enhance the performance of these sustainable polymers within the context of FDM. Various surface modification methods, such as plasma treatment, chemical etching, and UV irradiation, were utilized on biodegradable and recycled polymers, with the treatment process conducted under controlled conditions. Mechanical testing was done using a Tinius Olsen universal testing machine, with surface morphology analyzed through scanning electron microscopy. The outcome indicated that the tensile strength of polylactic acid improved by 15% with plasma treatment, while the thermal stability of recycled polyethylene terephthalate improved by 12% with chemical etching. Surface engineering developments on various techniques will be reviewed, particularly in optimizing them within FDM processes for different types of polymers. Different surface modifications will be compared here, analyzing aspects such as adhesion, endurance, and more overall performance. This comparison provides a fundamental outlook into the relationship between surface treatment and polymer performance, paving the way for optimization of FDM processes in sustaining material applications. These findings serve as further guidance toward making additive manufacturing much more sustainable and efficient through advanced surface engineering. The numerical improvement of material properties observed in the study will aid in further endeavors towards achieving sustainability and efficiency in additive manufacturing.

Dynamics of deposition and removal of a fluorocarbon film in the cyclic process of plasma-chemical etching of silicon

In situ measurements of the dynamics of deposition and etching of a fluorocarbon film (FCF) during cyclic plasma-chemical etching of silicon using a laser interferometer have been carried out. Direct measurements of the deposition and etch rates, as well as the etch time of the FCF, open up new possibilities for optimizing the cycle procedure. For example, adjusting the etching time of the FCF improves the selectivity of the etching process.

Surface metamorphosis techniques for sustainable polymers: Optimizing material performance and environmental impact

The transition to sustainable polymers is crucial for reducing the environmental footprint of additive manufacturing, particularly in fused deposition modeling (FDM). This study investigates surface metamorphosis techniques—methods to modify polymer surfaces at micro and nanoscale levels to enhance performance and minimize environmental impact. We explore plasma treatment, chemical etching, and laser texturing on biodegradable and recycled polymers, assessing their effects on surface properties, such as adhesion, roughness, and chemical resistance. Our results demonstrate significant enhancements in mechanical properties. For example, PLA’s tensile strength increased from 55.3 MPa (untreated) to 63.8 MPa (plasma treated), and its elongation improved from 4.2% to 5.1%. PHA showed a similar trend, with tensile strength rising from 45.1 MPa to 52.6 MPa, and elongation increasing from 5.6% to 6.4%. rPET and rPP also exhibited improvements, indicating the effectiveness of these surface treatments. Employing a multi-criteria decision-making approach, we assess and prioritize these techniques based on their mechanical enhancements and sustainability profiles. While this study presents hypothetical results, it establishes a comprehensive framework for optimizing surface metamorphosis processes, guiding future experimental research. Our findings suggest that tailored surface modifications can significantly improve the performance and environmental sustainability of polymers in FDM, offering pathways for integrating eco-friendly materials into advanced manufacturing. This work contributes to the development of green manufacturing technologies by highlighting surface metamorphosis as a key strategy for achieving high-performance and sustainable materials.

Application of Graphene in Acoustoelectronics.

An interdigital transducer structure was fabricated from multilayer graphene on the surface of the YZ-cut of a LiNbO3 ferroelectric crystal. The multilayer graphene was prepared by CVD method and transferred onto the surface of the LiNbO3 substrate. The properties of the multilayer graphene film were studied by Raman spectroscopy. A multilayer graphene (MLG) interdigital transducer (IDT) structure for surface acoustic wave (SAW) excitation with a wavelength of Λ=60 μm was fabricated on the surface of the LiNbO3 crystal using electron beam lithography (EBL) and plasma chemical etching. The amplitude-frequency response of the SAW delay time line was measured. The process of SAW excitation by graphene IDT was visualized by scanning electron microscopy. It was demonstrated that the increase in the SAW velocity using graphene was related to the minimization of the IDT mass.

Innovative PEEK in Dentistry of Enhanced Adhesion and Sustainability through AI-Driven Surface Treatments.

This research investigates using Polyether ether ketone (PEEK) in dental prosthetics, focusing on enhancing the mechanical properties, adhesion capabilities, and environmental sustainability through AI-driven data analysis and advanced surface treatments. The objectives include improving PEEK's adhesion to dental types of cement, assessing its biocompatibility, and evaluating its environmental impact compared to traditional materials. The methodologies employed involve surface treatments such as plasma treatment and chemical etching, mechanical testing under ASTM standards, biocompatibility assessments, and lifecycle analysis. AI models predict and optimize mechanical properties based on extensive data. Significant findings indicate that surface-treated PEEK exhibits superior adhesion properties, maintaining robust mechanical integrity with no cytotoxic effects and supporting its use in direct contact with human tissues. Lifecycle analysis suggests PEEK offers a reduced environmental footprint due to lower energy-intensive production processes and recyclability. AI-driven analysis further enhances the material's performance prediction and optimization, ensuring better clinical outcomes. The study concludes that with improved surface treatments and AI optimization, PEEK is a promising alternative to conventional dental materials, combining enhanced performance with environmental sustainability, paving the way for broader acceptance in dental applications.

Plasma-Chemical and Reactive Ion Etching of Gallium Arsenide in Difluorodichloromethane with Helium

Plasma-Chemical and Reactive Ion Etching of Gallium Arsenide in Difluorodichloromethane with Helium

Dynamics of Deposition and Removal of a Fluorocarbon Film in the Cyclic Process of Plasma-Chemical Etching of Silicon

Dynamics of Deposition and Removal of a Fluorocarbon Film in the Cyclic Process of Plasma-Chemical Etching of Silicon

Development and Performance Evolution of Medium-Pressure He/SF6/O2-Based Plasma and Wet Chemical Etching Process for Surface Modification of Fused Silica

Development and Performance Evolution of Medium-Pressure He/SF6/O2-Based Plasma and Wet Chemical Etching Process for Surface Modification of Fused Silica

Passivation of a Conductive System of Integrated Circuits with a Layer of Aluminum Nitride

Passivation of the film conductive system of integrated circuits makes it more reliable by increasing the resistance to electromigration. The problem of manufacturing a passivating layer on the formed current-conducting system of an integrated circuit, obtained in a single technological cycle, including isotropic plasma-chemical etching of an aluminum alloy layer to a depth of 8–12 nm and isotropic plasma-chemical nitriding of the surface of the obtained current-carrying tracks until the aluminum nitride thickness from 10 to 50 nm, is considered. This task makes it possible to form a dielectric film based on silicon dioxide on a silicon substrate with active regions, etch contact windows to active elements of the substrate in the dielectric film, deposit a barrier layer 0.005–0.050 µm thick, and deposit an aluminum alloy film 0.5–2.0 um and much more.

In situ diagnostics of the Si etching structures profile in ICP SF6/C4F8 plasma: Macrostructures

In this work, we studied the influence of technological parameters of plasma chemical etching of silicon on silicon etching rate, photoresist etching rate, etching selectivity of silicon in relation to a photoresist, and sidewall angle of etched structures. It was found that the silicon etching rate increases with raising percentage of SF6 in the gas mixture (25%–50%), pressure (1–2.5 Pa), high-frequency (HF) power (1000–2000 W), and bias voltage module (15–75 V) and decreases with a raising total flow rate of the gas mixture (5–35 SCCM) due to the increasing passivation efficiency of the sample surface. The etching selectivity increases with a raising percentage of SF6 and pressure and decreases with the raising total gas flow rate, HF power, and bias voltage module due to different influences of technological parameters on the photoresist etching rate. In addition, based on the obtained results, a common regularity between the sidewall angle and the optical emission spectra was revealed. The method of in situ diagnostics was proposed, namely, controlling the sidewall angle by a ratio of emission intensities of a carbon line (517.1 nm) to a fluorine line (685.8 and 703.9 nm) designated as parameter X. It was found that the sidewall angle of etched structures takes certain values depending on the value of the X parameter. The ranges of X values at which the sidewall angle is acute, right, and obtuse were estimated. So, at values of X from ≈0.15 to ≈0.35, an acute angle (from 81° ± 0.5° to 89° ± 0.5°) is obtained; at X from ≈0.35 to ≈0.42, a right angle is obtained (90° ± 0.5°); and at X from ≈0.42 to ≈0.75, the values of the sidewall angle are in the range from 91° ± 0.5° to 94° ± 0.5°, no matter which technological parameters were set. Experiments were conducted for etching windows with linear dimensions from 0.5 × 20 to 2 × 20 mm.

Optimization, fabrication and characterization of a binary subwavelength cylindrical terahertz lens

A problem of optimizing the subwavelength microrelief of a binary cylindrical transmissive diffractive lens (DL) with a 300-mm focal length for a wavelength of λ=141 μm was considered. High-resistivity silicon was chosen as the DL substrate material. The angle of incidence of the illuminating beam was taken to be π/6. The optimization parameters were the height of the DL profile and the fill factor of the groove. The main goal of optimizing the design was to increase the diffraction efficiency of the lens. The DL diffraction efficiency was calculated using a Fourier mod method. The DL was fabricated by plasma-chemical etching (Bosch process) of the surface of a silicon substrate. The diffraction efficiency of the calculated lens was estimated to be 70%. However, a full-scale experiment showed the real efficiency to be much lower. These differences are related to both errors in the manufacturing process of the DL and non-ideal thickness parameters of the silicon wafers.

Получение цветного наноструктурированного слоя аморфного кремния при травлении в хлорсодержащей плазме

It is shown that in the self-forming mode in the plasma etching process of amorphous silicon structures (α-Si)/SiO2/Si and (α-Si)/Pt/SiO2 /Si in chlorine-containing plasma (Cl2/Ar), it is possible to obtain a multicolored surface from nanoconus and nanowire structures of α-Si.The mechanism of formation of such structures during plasma chemical etching is discussed. The reflection spectra of colored films are given. The bright colors of the surface are caused by the resonant reflection of light in the layers of nanoconus and nanowire structures of α-Si with a sublayer of α-Si nanometer thickness.

Controlling Silicon Etching Parameters in RF CHF3 Plasma by Optical Emission Spectroscopy

The processes of plasma-chemical and reactive-ion etching of silicon in trifluoromethane (CHF3) are studied using optical emission spectroscopy. The dependences of the radiation intensities of atoms and mol-ecules on the etching time, input power, and pressure of the plasma-forming gas are obtained and analyzed.

OES diagnostics of NF3/Xe plasma for deep structures in LiNbO3

In this work, in situ non-perturbing method of optical emission spectroscopy is used to examine the features of the emission spectra of NF3/Xe plasma, which can be used for the process of continuous plasma-chemical etching of lithium niobate. To understand the physicochemical processes occurring in plasma, the influence of high-frequency power, pressure in the chamber, bias voltage and substrate temperature on the emission intensities of the F, N, Xe lines was studied. It was determined that increasing the bias voltage from -300 to -50 V and the temperature from 50 to 300°C doesn’t change the relative intensities of the analysed spectral lines, while increasing the high-frequency power from 500 to 750W and decreasing the pressure from 1.95 to 0.95Pa increase the intensities of the F, N, Xe lines.

Temporary Bonding Technology for Integration of Wafers of Different Diameters

The research paper describes the technology of temporary bonding for carrying out technological operations with semiconductor wafers with a diameter of 100 mm or less on equipment for a wafer diameter of 150 mm. The main technological processes for manufacturing a silicon substrate 300 μm thick with blind microholes (vertical grooves) 100 μm in diameter using temporary bonding technology are presented. Investigations of the elemental analysis of the formed structure of metals in blind microholes were carried out on the basis of spectral ellipsometry. Metallization was carried out by a combination of methods of atomic layer and magnetron sputtering, chemical and electrochemical deposition. The effect of expansion of the groove walls during deep plasma-chemical etching of silicon is shown. The developed technology of temporary bonding is intended for the production of silicon interposers with TSV holes, 2.5D and 3D microassemblies.

Wet scandium etching for hard mask formation on a silicon substrate

Nowadays, microelectronics requires the search for materials, including masks for creating structures. The intermediate hard mask strategy is one of the key issues in achieving a good balance between lithography and etching in microelectronics manufacturing. One of the interesting challenges in microelectronics and photovoltaics is the creation of interlayer, vertically oriented silicon arrays on Si substrate for semiconductor devices with multifunctional purposes. The fabrication of such structures is still a serious technological problem and requires searching for approaches and materials. In this work, we propose using scandium as a hard mask material over silicon due to its high resistance to plasma chemical etching and low sputtering coefficient. We have shown that a wet etching of the scandium layer with a thickness of several nanometers can be used to obtain pattern structures on silicon with a resolution of up to 4 µm, which is a good result for the wet etching approach. The scandium was found to be an excellent resistant mask over silicon with the lowest etch rate compared to other metal masks under the selected plasma etching conditions. Therefore, a scandium hard mask can open up possibilities for the formation of different microscale topographical patterns.

Recent progress in superhydrophobic rubber coatings

Under the extreme climate, the demand for surface protection from wetting and icing has increased extensively. Many studies focused on developing superhydrophobic coatings from elastic rubbers because of their excellent wear resistance properties. This review not only compares the specific strategies developed to produce superhydrophobic rubber coatings but also analyses the characteristics and applications of superhydrophobic rubber coatings. The common reinforcing agent (SiO2 nanoparticles) and the filler (CaCO3) of rubber products were used to create nano- and microroughness for capturing air on the superhydrophobic surface. Hydrophobic agents were further incorporated to reduce the surface energy of rubber coatings. Besides inorganic nanoparticles, superhydrophobic rubber coatings have been successfully produced using carbonaceous materials, namely multi-walled carbon nanotubes, carbon black and carbon nanofibers. Without nanoparticles, a rough surface could be created through anodizing, laser treatment, plasma jet treatment, chemical etching, or templating. Besides showing large water contact angles (>150°) and low sliding angles (<10°), superhydrophobic rubber coatings showed anti-icing properties on glass insulators. Superhydrophobic rubber coatings were applied on fabric, concrete and asphalt pavement to prevent wetting. Future development should concentrate on the improvement of coating durability. More superhydrophobic natural rubber coatings with improved sustainability should be developed as well.

Formation of Nanosized Structures on the Silicon Surface by a Combination of Focused Ion Beam Methods and Plasma-Chemical Etching

Formation of Nanosized Structures on the Silicon Surface by a Combination of Focused Ion Beam Methods and Plasma-Chemical Etching

Plasma-Chemical and Reactive-Ion Etching of Silicon in Tetrafluoromethane with Argon

Plasma-Chemical and Reactive-Ion Etching of Silicon in Tetrafluoromethane with Argon

Groups of Ge nanoislands grown outside pits on pit-patterned Si substrates

Ordered arrays of Ge quantum dot groups (QDs) were grown on pit-patterned silicon-on-insulator (SOI) substrates with deep pits, prepared by electron beam lithography (EBL) and plasma-chemical etching (PCE). Experiments were carried out for the square and hexagonal pit lattices with the lattice period varied. The QDs were found to be sited at the periphery of pits. It was demonstrated that for both pit lattice types the number of QDs per pit can be controlled by varying the period of the pit lattice. The Monte Carlo (MC) simulations of QDs growth on pit-patterned Si substrates were carried out, using the model, which takes strain into account. The island patterning depending on the inter-pit distance is interpreted as the result of competition between stress-driven QD nucleation and Ge migration downward into the pits, which serve as the sinks for Ge atoms.