Metal Films Research Articles

A Noncontact Method for Estimating Thin Metal Film Adhesion Strength Through Current-Induced Void Growth

Abstract Studies have reported that the electromigration-induced void growth velocity in metal thin films is inversely related to the adhesion strength of the metal thin film with the base and passivation layers. It was also observed that the contribution of interface adhesion strength to electromigration resistance decreases with an increase in temperature. In this study, an expression is derived for the diffusive void growth velocity induced by electromigration from a generalized thermodynamically consistent continuum-based theory for reaction–diffusion driven solid-state interface evolution. This relation captures the effect of adhesion with the base and passivation layers on electromigration resistance of thin metal films. Electromigration experiments were carried out at elevated temperatures and high current density to induce voiding in thin Cu metal film deposited on a base layer of TiN and passivated with TiN or SiNx. The degradation of interface adhesion strength with temperature is modeled using an Andrade-type of relationship. The void growth rates characterized in these experiments are combined with the expression for void growth rate to estimate the interface adhesion strength for the Cu–TiN and Cu–SiNx interfaces. The methodology for estimating the adhesion strength of the metal-passivation layer interface is validated through comparison with interface adhesion strengths from mechanical de-adhesion tests reported in the literature.

Impact of structural parameters on multimode D-shaped optical fiber refractive index sensors for different materials

In this work, a D-shaped optical fiber sensor has been experimentally developed to compare how the refractive index (RI) of a water analyte (used as the cladding layer over a small length of the stripped D-polished optical fiber) changes due to the inclusion of an unknown concentration of two distinct materials, one with a low RI and the other with a high RI. No metal film is deposited in the proposed D- shaped optical fiber sensor and hence we demonstrate the sensor's ability to detect the lowest concentration of the added material into the water analyte without employing the surface plasmon modes. A side-polished multi-mode optical fibre with various sensing lengths and polishing depths is used to construct the D-shaped fibre sensor. Experimental results verify that in a tunable refractive index (RI), the sensitivity increases with the sensing length due to the increase in the interaction area between the surrounding material and the sensing area. The sensitivity also increases with polishing depth in the high-RI range for materials with higher concentrations. The D-shaped fibre sensor's maximum sensitivity of 25.076 a.u./RIU is attained in the range of low refractive index values (1.3329) to (1.3345) RIU. Nonetheless, its maximum sensitivity drops to 0. 317 a.u./RIU at the high refractive index region of 1.348–1.4048 RIU. This sensor is predicted to have potential uses in low-RI materials with very low concentrations. Therefore, the best D-shape fibre sensor was used to detect the lowest concentration of the sodium chloride solution in the low refractive index range, and it was found that the lowest detected concentration was 0.012% with a high sensitivity of 327.32 a.u./RIU.

Ligand-Oxidation-Based Anodic Synthesis of Oriented Films of Conductive M-Catecholate Metal-Organic Frameworks with Controllable Thickness.

Effective control over the crystallization of metal-organic framework (MOF) films is of great importance not only for the performance study and optimization in related applications but also for the fundamental understanding of the involved reticular chemistry. Featuring many technological advantages, electrochemical synthesis has been extensively reported for many MOF materials but is still challenged by the production of dense oriented films with a large-range tuning of thickness. Here, we report a ligand-oxidation-based anodic strategy capable of synthesizing oriented films of two-dimensional (2D) and three-dimensional (3D) conductive M-catecholate MOFs (2D Cu3(HHTP)2, 2D Zn3(HHTP)2, 2D Co3(HHTP)2, 3D YbHHTP, and 2D Cu2TBA) with tunable thicknesses up to tens of micrometers on commonly used electrodes. This anodic strategy relies on the oxidation of redox-active catechol ligands and follows a stepwise electrochemical-chemical reaction mechanism to achieve effective control over crystallizing M-catecholate MOFs into films oriented in the [001] direction. Benefiting from the electrically conductive nature, Cu3(HHTP)2 films could be thickened at a steady rate (17.4 nm·min-1) from ∼90 nm to 10.7 μm via a growth mechanism differing from those adopted in previous electrochemical synthesis of dense MOF films with limited thickness due to the self-inhibition effect. This anodic synthesis could be further combined with a templating strategy to fabricate not only films with well-defined 2D features in sizes from micrometers to millimeters but also high aspect ratio mesostructures, such as nanorods, of Cu3(HHTP)2.

Spatial asymmetry of optically excited spin waves in anisotropic ferromagnetic film

We analytically discuss and micromagnetically prove the ways to tune the spatial asymmetry of the initial phase, amplitude, and wavevectors of magnetostatic waves driven by ultrafast laser excitation. We consider the optical pulse to heat a thin ferromagnetic metallic film and abruptly decrease the saturation magnetization and the parameter of uniaxial anisotropy. The two corresponding terms of laser-induced torque have different azimuthal symmetries, with the 4-fold symmetry of the demagnetization-related term, and the isotropic distribution of the anisotropy-related term. As a result, the initial phase and amplitude of excited magnetostatic waves have a non-trivial azimuthal distribution tunable with the angle between the external magnetic field and anisotropy axis, and the laser spot diameter. Moreover, the variation of these parameters tunes the distribution of wavevectors, resulting in additional asymmetry between the spectral components of the waves propagating in different directions.

Propagation of surface plasma waves in metal films perforated with n × n lattices of holes (n = 2 to 72).

The propagation of surface plasma waves (SPWs) in 90 nm-thick Au films perforated with n × n square lattices of circular holes, referred to as n-metal photonic crystals (n-MPCs), is investigated. The hole period was set to 3 µm with n = 2, 4, 6, 8, 12, 18, 24, 36, and 72. For each n-MPC, the total number of holes was conserved to 5184 (= 72 × 72), which were grouped to form an Mn × Mn (Mn = 72/n) array of lattices, evenly spaced on 384 × 384 µm2. The n-MPCs were individually integrated on semi-insulating GaAs substrates. In the transmission through them, the primary peak by the SPW excited at the n-MPC/GaAs interface exhibits clear variation with n in its wavelength and intensity. It begins to appear for n ∼ 4 and its intensity is increased with n but saturated for n∼ x> 36 with Fano lineshape. These imply the SPW excitation is significantly affected by the boundary and number of holes in each lattice. Such lattice size-dependent transmission is compared with the absorption of the quantum dot infrared photodetectors identically coupled to the n-MPCs. In the absorption, the saturation of the peak intensity is observed for n∼ x> 24, lower than the ∼36 in the transmission. Their difference is characterized with the SPW propagation and decay that critically depend on the dielectric properties of devices as well as the number of holes and boundaries of each lattice in plasmonic excitation.

Functionalizing self-assembled monolayers to reduce interface scattering in ruthenium/dielectric for next-generation microelectronic interconnects

As the number of transistor increases in modern devices, the resistivity of metal lines increases with the downscaling of the vias dimension due to the increased in surface scattering of electrons. Herein, we evaluated the electrical performance and the adhesion strength of the Ru/SiO2 substrate upon functionalizing with benzyliminetriethoxysilane (BITES) and aminoproyltriethoxysilane (APTES) self-assembled monolayers (SAMs)s at the Ru/SiO2 interface. The covalent bonding and retention of the SAM film on the SiO2 surface were characterized via angle-resolved X-ray Photoelectron Spectroscopy (AR-XPS) and Time-of-Flight Secondary Ion Mass Spectrometry (Tof-SIMS), respectively. According to the Fuchs–Sondheimer (FS) model and scratch test, the specularity parameter and the adhesion strength of the Ru/BITES/SiO2 simultaneously improved after thermal annealing compared to the non-functionalized Ru/SiO2 substrate. The effect of different SAM’s terminal groups (amine and benzylimine) on the electron scattering behavior was investigated based on the formation of an interface dipole upon chemisorption of organic molecules on the metal film. Our results indicate that SAM with the benzylimine terminal group formed a larger positive dipole at the SAM layer of the Ru/BITES/SiO2 interface compared to the Ru/APTES/SiO2, leading to an increased in specular electron scattering events and, thus an enhanced electrical performance of the Ru/BITES/SiO2.

Thermally Reconfigurable, 3D Chiral Optical Metamaterials: Building with Colloidal Nanoparticle Assemblies.

The three-dimensional, geometric handedness of chiral optical metamaterials allows for the rotation of linearly polarized light and creates a differential interaction with right and left circularly polarized light, known as circular dichroism. These three-dimensional metamaterials enable polarization control of optical and spin excitation and detection, and their stimuli-responsive, dynamic switching widens applications in chiral molecular sensing and imaging and spintronics; however, there are few reconfigurable solid-state implementations. Here, we report all-solid-state, thermally reconfigurable chiroptical metamaterials composed of arrays of three-dimensional nanoparticle/metal bilayer heterostructures fabricated from coassemblies of phase change VO2 and metallic Au colloidal nanoparticles and thin films of Ni. These metamaterials show dynamic switching in the mid-infrared as VO2 is thermally cycled through an insulator-metal phase transition. The spectral range of operation is tailored in breadth by controlling the periodicity of the arrays and thus the hybridization of optical modes and in position through the mixing of VO2 and Au nanoparticles.

Ultrathin MXene film interaction with electromagnetic radiation in the microwave range

The quick progress in communication technologies demands superior electromagnetic interference (EMI) shielding materials. However, achieving a high shielding effectiveness (SE) with thin films, which is needed for microscale, flexible, and wearable devices, through absorption of EM radiation remains a challenge. 2D titanium carbide MXene, Ti3C2Tx, has been shown to efficiently reflect electromagnetic waves. In this paper, we investigated the electromagnetic shielding of ultrathin printed Ti3C2Tx films and recorded absorption up to 50% for 4 nm-thick films. This behavior is explained by impedance matching. Analysis of the sheet impedance in the X-band frequency range allows us to correlate the EMI shielding mechanism with the electrical conductivity measured within the same range. The average bulk in-plane conductivity for 4 to 40 nm-thick films reaches 106 S/m, while the average relaxation time is estimated at around 2.3 ps. Our figures of merit are similar to those reported for ultrathin metal films, such as gold, showing that an abundant MXene material can replace noble metals. We demonstrate that the MXene conductivity mechanism does not change from direct current to THz. The conventional method of reporting EMI SE is correlated with absolute values of transmitted, reflected, and absorbed power, which allows us to interpret previous results on MXene EMI shielding. Considering the easy deposition of thin MXenes films from solution onto a variety of surfaces, our findings offer an attractive alternative for shielding microscale devices and personal electronics.

Tailored nanocrystalline Niobium coatings on steel substrates for superior resistance to micro-crack initiation

Fracture of metallic thin films during deformation hampers extensive applications of coated engineering components. In this study, the resistance to micro-crack initiation of Niobium (Nb) coatings deposited on stainless steel substrates is improved remarkably by tuning the substrate bias voltages during unbalanced magnetron sputtering. With the tailored nanocrystalline microstructure, the failure strain for coating fracture is increased to 30 %, which is far greater than that of previous metallic coatings (below 10 %). Microstructure characterizations reveal that intergranular nano-pinholes and amorphous phases can be eliminated effectively with a moderate ions bombardment effect to avoid brittle film fracture. At the same time, compact and homogenous nanocrystalline grains with appropriate intragranular defects are obtained via enhanced atom diffusivity during deposition. Therefore, large plastic deformation can be accommodated through both stress-driven grain coarsening and continuous dislocation plasticity, avoiding fracture of the Nb coatings.

High-sensitivity optical fiber SPR sensor with cascaded biconical fiber and hetero-core structure for simultaneous measurement of seawater salinity and temperature

A novel dual-channel optical fiber surface plasmon resonance (SPR) sensor, which achieves high-sensitivity simultaneous measurement of seawater salinity and temperature, was designed and verified. The hetero-core structure based on no-core fiber (NCF) with 40 nm thick Au film and polydimethylsiloxane (PDMS) overlaying was utilized to excite the SPR effect and serve as the temperature sensing channel. In order to effectively separate from the temperature SPR dip, a silver/gold bimetallic film was deposited on the surface of the biconical fiber with a grinding angle of 14° to construct the salinity channel cascaded with the temperature channel, where the metal thickness was determined as Ag/Au: 30 nm/10 nm. The simulation and experimental results showed that the bimetallic film used in this article can significantly improve the figure of merit (FOM) of the sensor compared with the optical fiber SPR sensor deposited with a single kind of metal film. In addition, further experimental results on salinity and temperature indicated that the proposed sensor had a salinity sensitivity of 0.73 nm/‰ and a temperature sensitivity of −2.43 nm/℃, and demonstrated the advantages of ease of manufacturing, acceptable repeatability, and good stability. Therefore, the proposed dual-channel optical fiber SPR sensor has high research value and application prospects in the field of ocean measurement.

Emergent superconductivity in topological-kagome-magnet/metal heterostructures

Itinerant kagome lattice magnets exhibit many novel correlated and topological quantum electronic states with broken time-reversal symmetry. Superconductivity, however, has not been observed in this class of materials, presenting a roadblock in a promising path toward topological superconductivity. Here, we report that novel superconductivity can emerge at the interface of kagome Chern magnet TbMn6Sn6 and metal heterostructures when elemental metallic thin films are deposited on either the top (001) surface or the side surfaces. Superconductivity is also successfully induced and systematically studied by using various types of metallic tips on different TbMn6Sn6 surfaces in point-contact measurements. The anisotropy of the superconducting upper critical field suggests that the emergent superconductivity is quasi-two-dimensional. Remarkably, the interface superconductor couples to the magnetic order of the kagome metal and exhibits a hysteretic magnetoresistance in the superconducting states. Taking into account the spin-orbit coupling, the observed interface superconductivity can be a surprising and more realistic realization of the p-wave topological superconductors theoretically proposed for two-dimensional semiconductors proximity-coupled to s-wave superconductors and insulating ferromagnets. Our findings of robust superconductivity in topological-Chern-magnet/metal heterostructures offer a new direction for investigating spin-triplet pairing and topological superconductivity.

Изучение принципов построения широкополосной колебательной СВЧ системы на примере резонатора Фабри-Перо

In telecommunications and radar systems of the centimeter and millimeter wave ranges, span klystrons are widely used as medium and high power amplifiers. The use of high-quality resonators makes it possible to realize high efficiency and amplification factors. However, typical designs of 2 - 4 resonator klystrons have a bandwidth of 0.1 - 0.5 % due to the need to use resonators with a high Q – factor. The well-known method of expanding the amplified frequency band in the centimeter range up to 7 – 12 % and in the millimeter range up to 1 - 2 % consists in tuning the frequency of the intermediate klystron resonators by several percent of the central amplification frequency. But in this case, it is required to use 10 - 12 resonators. The authors of the work discovered that when a millimeter range electromagnetic wave is reflected from an electrodynamics system in the form of a metal film on the surface of a semiconductor layer, the input resistance phase-frequency characteristic of this system consists of a chain of frequency intervals with turnings from a positive phase-frequency characteristic to a negative one and vice versa. The possibility of constructing a phase shifter with a negative phase frequency response based on this phenomenon is demonstrated and its application for expanding the resonant frequency band is considered on the example of the Fabry - Perot interferometer model. This resonator contains a phase shifter in the form of a semiconductor layer F with a thickness DF, a conductivity σF, a relative dielectric eF and a magnetic mF permeability. The outer surface of the layer F contains a metal mirror, and the inner surface is adjacent to the layer W. The layer W which has the thickness of DW, eW, mW forms the internal space of the resonator. The external environment I with mI and eI. adjoins the layer W. A plane electromagnetic wave propagates in I media so that it excites the resonator at a wavelength of l0. The use of a phase shifter makes it possible to increase the resonant wavelength band Δl/l0 by 2 - 4 times and with an electromagnetic field amplification coefficient |G(l)| in the W layer by 10 - 20 times (the value of Dl/l0 corresponds to 0.707 max |G(l0)|). An increase of σF leads to an amplitude-frequency characteristic transforming of the field gain function G(l0) from two maxima to one maximum form with a transition through a flat top. In this case max |G(l0)| decreases and Dl/l0 increases. For the case, when the function |G(l)| has a flat top, an increase in the wave resistance ρW of the layer W with a corresponding decrease in sF and optimal values of DW leads to an increase in |G(l0)|. When this occurs, Dl/l0 becomes lower.

Novel application of electrochemical test for the controllable electrodeposition of Cu2O and metallic Cu film

As important industrial materials, the preparation of metallic copper and cuprous oxide (Cu2O) film is a hotspot in related fields. In this work, Cu2O and metallic copper films were controllably fabricated on the conductive substrate in an electrolyte containing 0.02 M cupric acetate and 0.1 M sodium acetate at different voltages. Linear sweep voltammetry test, as an effective way, was used to determine the selection of electrodeposition voltage. Pure Cu2O film can be prepared at a lower deposition voltage, and metallic copper film can be obtained at a higher deposition voltage and a longer deposition time. The obtained Cu2O film has complex surface morphology and exhibited n-type conductivity. The composition and morphology of the films were related to the deposition voltage. These results provide a new strategy and sight for the controllable preparation of cuprous oxide and metallic copper in the field of solar cells and integrated circuits.

Influence of the Gas Preheating Temperature on the Microstructure and Electrical Resistivity of Copper Thin Films Prepared via Vacuum Cold Spraying

Vacuum cold spraying (VCS) has emerged as an environmentally sustainable method for fabricating ceramic and metal films. A high particle impact velocity is a critical factor in the deposition of metal particles during the VCS process, which can be significantly enhanced through gas preheating. This study employs Computational Fluid Dynamics (CFD) simulations to investigate the substantial impact of gas preheating temperature on particle impact velocity and temperature. Elevating the gas temperature leads to higher particle impact velocity, resulting in severe deformation and the formation of dense copper films. The experimental results indicate improvements in both film compactness and electrical properties with gas preheating. Remarkably, the electrical resistivity of the copper film deposited at a gas preheating temperature of 350 °C was measured at 4.4 × 10−8 Ω·m. This study also examines the evolution of cone-shaped pits on the surface of copper films prepared on rough substrates. VCS demonstrates a self-adaptive repair mechanism when depositing metal films onto rough ceramic substrates, making it a promising method for ceramic surface metallization.

A CFD study of the gas reaction path in growth of InN films in metal–organic chemical vapor deposition

During simulation of the growth of indium nitride (InN) thin films in metal–organic chemical vapor deposition (MOCVD), different choices of kinetic parameters (activation energy Ea and pre-exponential factor A) for gas-phase reactions give rise to many uncertainties in the gas reaction path and growth rate. This study summarized and compared the kinetic parameters of gas-phase reactions during InN MOCVD growth. The InN MOCVD growth in a close-coupled showerhead reactor was simulated with varying kinetic parameters of gas-phase reactions. The effects of kinetic parameters on the gas reaction path were determined by comparing molar concentrations and growth rates of primary In-containing substances. The results show that with varying kinetic parameters, the gas reaction path is likely to be dominated by the addition or trimethylindium pyrolysis path, or to proceed through both reaction paths. Although the reaction path changes with varying kinetic parameters, the predicted growth rates do not vary substantially, because the total rate of transport of In-containing substances to the substrate changes little with the reaction path. The results also indicate that the contribution of pyrolytic products to the growth rate is greater than that of amine, whereas H radicals have minimal effect on the gas reaction path in InN MOCVD growth.

Engineering microcracks in MWCNT/elastomer bilayers for high-performance stretchable sensor development

Stretchable strain sensors in motion detection, health monitoring, and human-machine interfaces are limited by device sensitivity, linearity, hysteresis, stability, and reproducibility in addition to stretchability. Engineering defect structures in sensing material is an effective approach in modulating the material's physical properties, particularly those associated with mechanical responses. Here, we demonstrate that bilayers of carbon nanotubes deposited on an elastomer substrate are mechanically coupled. The microcrack size, density, and distribution in the nanotube thin film can be engineered through uniaxial tensile training to exhibit highly tunable and stable piezoresistive responses with sensitivity, linearity, range, and reproducibility. These responses far exceeding those in uniform metallic films, patterned structures, and composites. In addition, numerical analyses performed on a two-dimensional network model of the cracked nanotube film provide quantitative explanations of how crack configuration, and evolvement under strain, lead to the significant enhancements in stretchable sensor performance using current bilayer structures.

Scalable Bilayer MoS2‐Based Vertically Inverted p–i–n Light‐Emitting Diodes

AbstractHerein, a vertically inverted p–i–n architecture of light‐emitting diodes (LEDs) is designed for manufacturing feasibility and demonstrated scalable bilayer MoS2‐based LEDs. A 4 inch scale bilayer MoS2 is prepared by a two‐step growth method allocating the pre‐deposition of a few‐nm thick metal film and post‐sulfurization. To apply bilayer MoS2 for an active layer in LEDs, the film is transferred over ZnO nanoparticle layers, an electron transfer layer, and then the rest of the LED components are constructed by thermal deposition. This vertically inverted LED architecture allows individual organic or inorganic components to incorporate without degradation during the wet‐transfer process and transfer electron or hole carriers across separate layers, resulting in efficient radiative recombination in the MoS2 emitting layer. MoS2‐based LEDs exhibit electroluminescence of ≈5.41 cd m−2 throughout four active areas of 6.25 mm2 at a driving voltage of 7 V. Therefore, this achievement can overcome the drawbacks of existing transition metal dichalcogenides (TMDs)‐based optoelectrical applications and extend its potential in various fields, such as flexible, ultrathin, or transparent displays.

Adhesion of WTi to polyimide measured by complementary methods

Quantification of thin film adhesion to their substrates is crucial to ascertain reliable multi-material components, which are typically encountered in technologically relevant structures such as microelectronic devices. Metal-polymer interfaces have gained increased attention in the past since they open a new research field towards developing flexible electronic devices, yet their quantification is often experimentally challenging since standard routes to assess adhesion such as nanoindentation-based techniques or four-point bending may not be applicable due to lack of rigidity. In the present study interface adhesion of nominally 150 nm thin WTi films sputtered onto polyimide, part of a multi-material stack consisting of brittle and compliant materials, was determined experimentally. Upon contactless removal of the bilayer by etching a sacrificial layer, originally part of the multilayer stack, the WTi film showed cracks and buckles, which could be characterized by atomic force and confocal laser scanning microscopy. Hence, two models to quantify adhesion were compared: the model of tensile induced delamination – typically employed for metal films on compliant substrates – and the model of Hutchinson and Suo, which is usually applied on spontaneously formed, straight buckles. The first model reveals adhesion values for the native WTi-polyimide interface of 2.4 ± 0.8 J/m2 and the latter model 4.7 ± 2.3 J/m2. The slight difference in adhesion results, which are both rooted in the same theory, could be rationalized by the fact that the model for tensile induced delamination gives a measure of the lower bound of the adhesion energy. The overall rather lower adhesion values could be explained by additional transmission electron microscopy investigations conducted on the cross section of the interface, which reveals no interlinking morphology and a flat interface.

Advances in the Fabrication of Nanoporous Anodic Aluminum Oxide and Its Applications to Sensors: A Review.

Nanoporous anodic aluminum oxide (AAO) is an important template for 1D nanomaterial synthesis. It is used as an etching template for nanopattern transfer in a variety of contexts, including nanostructured material synthesis, electrical sensors, optical sensors, photonic and electronic devices, photocatalysis, and hardness and anticorrosion improvement. In this review, we focus on various fabrication methods, pore geometry modification, and recent advances of AAO, as well as sensor applications linked to our environment, daily life, and safety. Pore geometry is concerned with the material composition, applied voltage mold, electrolyte type, temperature, and anodizing time during the fabrication of AAOs and for adjusting their pore size and profile. The applied voltage can be divided into four types: direct current anodization (DCA), reverse pulse anodization, pulse anodization (PA), and hybrid pulse anodization (HPA). Conventional AAOs are fabricated using DCA and mild anodization (MA) at a relatively low temperature (-5~15 °C) to reduce the Joule heating effect. Moreover, the issues of costly high-purity aluminum and a long processing time can be improved using HPA to diminish the Joule heating effect at relatively high temperatures of 20-30 °C with cheap low-purity (≤99%) aluminum. The AAO-based sensors discussed here are primarily divided into electrical sensors and optical sensors; the performance of both sensors is affected by the sensing material and pore geometry. The electrical sensor is usually used for humidity or gas measurement applications and has a thin metal film on the surface as an electrode. On the contrary, the AAO optical sensor is a well-known sensor for detecting various substances with four kinds of mechanisms: interference, photoluminescence, surface plasma resonance, and surface-enhanced Raman scattering (SERS). Especially for SERS mechanisms, AAO can be used either as a solid support for coating metal nanoparticles or a template for depositing the metal content through the nanopores to form the nanodots or nanowires for detecting substances. High-performance sensors will play a crucial role in our living environments and promote our quality of life in the future.

Investigation of the SERS application of gold films deposited on uncured polydimethylsiloxane with tunable LSPR

We present an approach to investigate the localized surface plasmon resonance and surface-enhanced Raman scattering of gold films deposited on uncured polydimethylsiloxane via thermal evaporation. Differing from solid substrates, the liquid surface of uncured polydimethylsiloxane can serve as an isotropic substrate on which gold atoms nucleate and disperse to form characteristic microstructures in a controlled manner. By adjusting experimental parameters during film deposition, the absorption of resonant plasmon modes can be tuned in the visible spectral range due to the control of particle size and distribution in Au films. Furthermore, Raman measurements are conducted to investigate the enhancement of Raman signals in these films, and the experimental results are verified by simulation analysis. This work exhibits tunability of surface plasmon resonance frequency and enhanced Raman detection capability by depositing metal films on liquid surfaces, thus providing potential applications of these films in flexible biosensors and chemical detection.