Si Wafers Research Articles

Optimization of Grayscale Lithography for the Fabrication of Flat Diffractive Infrared Lenses on Silicon Wafers.

Grayscale lithography (GSL) is an alternative approach to the standard binary lithography in MEMS fabrication, enabling the fabrication of complicated, arbitrary 3D structures on a wafer without the need for multiple masks and exposure steps. Despite its advantages, GSL's effectiveness is highly dependent on controlled lab conditions, equipment consistency, and finely tuned photoresist (PR) exposure and etching processes. This works presents a thorough investigation of the challenges of GSL for silicon (Si) wafers and presents a detailed approach on how to minimize fabrication inaccuracies, aiming to replicate the intended design as closely as possible. Utilizing a maskless laser writer, all aspects of the GSL are analyzed, from photoresist exposure parameters to Si etching conditions. A practical application of GSL is demonstrated in the fabrication of 4-μm-deep f#/1 Si Fresnel lenses for long-wave infrared (LWIR) imaging (8-12 μm). The surface topography of a Fresnel lens is a good case to apply GSL, as it has varying shapes and size features that need to be preserved. The final fabricated lens profiles show a good match with the initial design, and demonstrate successful etching of coarse and fine features, and demonstrative images taken with an LWIR camera.

Matrices to enhance the ion yield of OLED molecules in ToF-SIMS: An interesting alchemist solution

Since the early days of time of flight secondary ion mass spectrometry (ToF-SIMS), increasing the ion signal has been crucial. It is even more crucial when performing tandem mass spectrometry experiments. To achieve this goal, many developments have been made over the years, which are divided into two categories: instrumental development and sample modification. The latter involves sample metallization, matrix deposition, or changing the temperature of the measurement. In this study, the possibility of using matrices to enhance the signals of organic light emitting device (OLED) molecules was explored. Seven molecules commonly used in OLEDs were separately deposited on Si wafers: Alq3, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile, Ir(mppy)3, N,N′-bis(naphthalene-1-yl)-N,N′-bis(phenyl)benzidine, 2,2′,7,7′-tetra(N,N-ditolyl)-amino-spiro-bifluor (STTB), and tris(4-carbazoyl-9-ylphenyl)amine. Using the same solvent, three different matrices with different thicknesses, common in matrix assisted light desorption ionization time of flight mass spectrometry, α-cyano-4-hydroxycinnamic acid, 2,5-dihydrobenzoic acid (DHB), and dihydrochloride N-(1-Naphthyl)ethylenediamine, were sprayed on these surfaces. Spectra were acquired for all compounds and spraying conditions in static ToF-SIMS experiments for Alq3 chemical imaging and depth profiling were performed. This allowed the investigation of the fragmentation pattern of the chosen matrices in ToF-SIMS and, thus, obtained a reference for these molecules. The results show that matrices can enhance the signal of fragments of the studied molecules, for example, the signal of STTB is increased with DHB spraying. Samples sprayed only with the solvent were also prepared to verify the impact of the matrices on the signal. Spraying with the solvent alone can enhance the signal even more than the matrices up to four times in the case of Alq3. This result opens new possibilities in the field of matrix-enhanced ToF-SIMS in terms of applications and matrix choices.

Photochemical modification of a diamond surface using a pulsed UV laser as the energy source

The use of an excimer benchtop pulsed UV laser as the energy source for the photochemical modification of the surface of diamond films is reported. Boron-doped nanocrystalline diamond (NCD) films were deposited on Si wafers via plasma-enhanced chemical vapour deposition (PECVD). The as-deposited films were characterised by scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction (XRD). Following characterisation, the surfaces of the films were subjected to a photochemical reaction with 2,2,2-trifluoroethyl undec-10-enoate using two different sources of radiation: a benchtop UV lamp (254 nm) and a KrF excimer pulsed UV laser (248 nm). The photochemically treated films were characterised by contact angle measurements and X-ray photoelectric spectroscopy (XPS) using non-treated films as a control. The use of a pulsed UV laser source was shown to reduce the photochemical reaction time from several hours to a few minutes.

Physical mechanism underlying the enhancement effect of carbon in heavily phosphorus-doped Czochralski silicon substrate on phosphorus out-diffusion within n/n+ epitaxial wafer

The effects of carbon in heavily phosphorus-doped Czochralski (HP-Cz) silicon (Si) substrates, with the concentrations across an order of magnitude from 1016 to 1017 cm−3, on the out-diffusion of phosphorus impurities within n/n+ epitaxial Si (Epi-Si) wafers have been investigated. It is found that the increase in the carbon concentration ([C]) from 1.0 × 1016 to 1.0 × 1017 cm−3 leads to the enhanced phosphorus out-diffusion within the n/n+ Epi-Si wafer when subjected to anneal at 1100 °C in an N2 or an O2 ambient or to anneal at 1150 °C in an N2 ambient, but hardly affects the phosphorus out-diffusion within the n/n+ Epi-Si wafer when subjected to anneal at 1150 °C in an O2 ambient. Based on the density functional theory calculations, it is derived that the increase in the [C] from 1.0 × 1016 to 1.0 × 1017 cm−3 in the HP-Cz Si substrate results in a significantly increased thermal equilibrium concentration of self-interstitial silicon (SiI) atoms at 1100 or 1150 °C, which, in turn, leads to the increased concentration of the SiI atoms that out-diffuse from the substrate to the epitaxial layer because the SiI atoms diffuse extremely fast in Si. Such a carbon-induced increase in the concentration of SiI atoms is believed to be responsible for the aforementioned enhanced phosphorus out-diffusion, which is predominantly dictated by the interstitialcy mechanism. In the case of anneal in the O2 ambient at sufficiently high temperatures such as 1150 °C, a large number of excessive SiI atoms injected into the Epi-Si wafer substantially mask the carbon enhancement effect on the phosphorus out-diffusion. Of technological significance, it is deduced that the [C] should be not higher than 1.0 × 1016 cm−3 in the HP-Cz Si wafers as the substrates of n/n+ Epi-Si wafers used for power devices.

Surface Photovoltage Spectroscopy as a Valuable Tool for Evaluating Oxidation Processes in the Microelectronics Industry

In the present study, the minority carrier diffusion length (MCDL), determined by surface photovoltage spectroscopy measurements, is compared in n‐ and p‐type Si wafers after their oxidation under different conditions using various tools (horizontal and vertical furnaces, atomic layer deposition (ALD), low‐pressure chemical vapor deposition, and plasma‐enhanced chemical vapor deposition). It is shown that MCDL varies significantly depending on the design of furnaces, oxidation temperatures, the type of gases used before and during oxidation, and their flow ratios. The type and crystal growth method of Si wafers used for the oxidation also play a significant role and influence MCDL. Additionally, MCDL after the deposition of alumina layers using ALD techniques is found to be significantly larger compared to that observed after the thermal oxidation of Si. The larger values of MCDL after the ALD of Al2O3 are detected independent of temperature and precursors used for the deposition. The origin of different MCDL values after various oxidation processes, with an emphasis on the formation of electrically active defects in Czochralski (CZ)‐ and float‐zone (FZ)‐grown Si wafers is discussed.

Non-contact targeted removal of remnant powder particles from additive manufacturing builds with nano-second laser pulsing

Post-production precision cleaning is one critical challenge in Additive Manufacturing (AM) production of high-value, critical parts/builds. A part shedding particle during its operational use could cause severe complications in critical applications such as medical devices and aerospace components. This study presents a non-contact precision particle removal procedure based on a novel Dry Laser Cleaning (DLC) framework. DLC utilizes the thermo-elastic wave generation/propagation and high-frequency surface acceleration fields to dislodge and remove remnant particles due to inertial forces from a well-defined (user-specified) cleaning zone in a non-contact manner, as opposed to cleaning the entire build surface, which could lead to undesirable re-deposition and re-location of particles as well as high cost. The removal of spherical Stainless Steel 316 L (SS316L) micro-particles commonly used in AM from polished, atomically flat Silicon (Si) wafer substrates with uniform high free surface energy using a nano-second laser pulse is experimentally and computationally investigated. In general, a rough surface has a lower average free surface energy; thus, its cleaning, compared to Si wafer, is less challenging. The data with the SS316-Si material pair offers a consistent baseline. In parallel to experiments, a fully-coupled thermo-mechanical finite element study is also conducted for transient surface acceleration simulations to predict the effectiveness of SS316L micro-particle removal from a Si wafer substrate with laser pulsation. It is observed that SS316L micro-particles with a diameter larger than 5.61 μm, 8.43 μm, and 12.24 μm can be removed entirely at 3 mm, 6 mm, and 9 mm distances from its epicenter, respectively. Accordingly, a work-of-adhesion of 990.8 mJ/m2 is selected between the SS316-Si material pair, consistent with the literature. The reported experiments and simulations demonstrate the potential of the proposed rapid precision particle removal procedure for cleaning critical powder-based AM builds, where the targeted removal of particles is essential for the safe and reliable operation of high-value builds and parts.

Cu-based nano-multilayer film produced by HiPIMS for antimicrobial properties and its application in photodetector

This paper reports on the use of high-power impulse magnetron sputtering to deposit Cu-based nano-multilayer films (CuZrTiAl) on Si wafers and AISI 304 stainless steel. Co-sputtering can be performed using multiple simultaneous targets to decrease the cost of manufacturing alloy targets at industrial scales. Co-sputtering mode allows variations in the power supplied to the various targets to control the intensity of the plasma jets and thereby tailor the composition of the deposited films. Our primary aim in this study was to elucidate the effects of Al target power (from 0.3 to 1.3 kW) on the structure and antibacterial properties of the resulting coatings. Varying the Al target power was shown to alter the chemical composition, layer thickness, and structure. EPMA results revealed that increasing the power from 0.3 to 1.3 kW caused a monotonic increase in Al content from 6.1 to 18.3 at%. Dark-field TEM images revealed that decreasing the period thickness from 8.6 to 4.6 nm caused the ultra-thin film Cu to transform into a single isolated nano-crystal, which facilitated the release of Cu ions to improve antibacterial effects (from 84 % to 99 % for Escherichia coli). This study also demonstrated the recycling of the proposed Cu-based nanoscale multilayer films to fabricate metal-doped ZnO nanowires for use in photodetectors. The photodetector achieved a photocurrent-to-dark-current ratio of 150 when using an LED light source with a wavelength of 365 nm.

Properties of NbxTi(1−x)N thin films deposited on 300 mm silicon wafers for upscaling superconducting digital circuits

Scaling superconducting digital circuits requires fundamental changes in the current material set and fabrication process. The transition to 300 mm wafers and the implementation of advanced lithography are instrumental in facilitating mature CMOS processes, ensuring uniformity, and optimizing the yield. This study explores the properties of Nb x Ti(1−x)N films fabricated by magnetron DC sputtering on 300 mm Si wafers. As a promising alternative to traditional Nb in device manufacturing, Nb x Ti(1−x)N offers numerous advantages, including enhanced stability and scalability to smaller dimensions, in both processing and design. As a ternary material, Nb x Ti(1−x)N allows engineering material parameters by changing deposition conditions. The engineered properties can be used to modulate device parameters through the stack and mitigate failure modes. We report characterization of Nb x Ti(1−x)N films at less than 2% thickness variability, 2.4% T c variability and 3% composition variability. Film resistivity (140–375 Ωcm) shows a strong correlation with the film oxygen content, while the critical temperature T c (4.6 K–14.1 K) is strongly affected by film stoichiometry and its microstructure has only a moderate effect on modifying T c. Our results offer insights about the interplay between film stoichiometry, film microstructure and critical temperature.

Localized Epitaxial Growth of 402 V Breakdown Voltage Quasi‐Vertical GaN‐on‐Si p‐n Diode on 200 mm‐Diameter Wafers

Localized epitaxy of gallium nitride (GaN) on silicon (Si) wafers is an efficient way to relax elastically the tensile stress generated in the GaN layer after growth, allowing epitaxy of thick layers for the fabrication of vertical power devices operating at high voltage. In this study, a 4.7 μm‐thick GaN layer is grown by metal–organic vapor phase epitaxy on 200 mm‐diameter Si wafers for the fabrication of quasi‐vertical Schottky and p‐n diodes. The uniformity of the doping concentration in the layer is mapped spatially by scanning spreading resistance microscopy, while scanning capacitance microscopy illustrates the differently doped regions in the p‐n diode. The net doping concentration is extracted by capacitance–voltage (C–V) measurements and it is found to be about 3 × 1016 cm−3. On a 140 μm‐diameter quasi‐vertical p‐n diode, destructive breakdown occurs at 402 V, with no periphery protection on the device, demonstrating that localized epitaxy of GaN on Si has great potential for vertical high‐power devices.

The Effect of Deposition Temperature on TiN Thin Films for the Electrode Layer of 3D Capacitors Prepared by Atomic Layer Deposition

The TiN thin film is considered a promising electrode layer for 3D capacitors. In this study, TiN thin films were prepared on Si substrates using atomic layer deposition (ALD) at various temperatures from 375 °C to 475 °C. The crystallization behavior, microstructure, and conductance properties of those TiN thin films were investigated. The resistivity of TiN thin films deposited on Si wafers can reach as low as 128 μΩ·cm. TiN thin films showed lower resistivity and worse uniformity with the deposition temperature increasing. In addition, the aging of TiN thin films may weaken the device performance. Optimized deposition parameters were found and full-coverage deposition of thin films on the wall of deep holes with an aspect ratio of approximately 14 has been successfully achieved. The results would be a good reference for the development of 3D capacitors and other microelectronics components.

Fabrication of a sharp Si protrusion with a faceted apex grown from a surface-melted silicon wafer under high electric and magnetic fields: application to field emission electron sources

A silicon (Si) protrusion, grown on a narrow path of a Si(001) wafer by surface melting via resistive heating, was sharpened by applying a local high electric field under a magnetic field during the growth. The electric field caused local stress to the surface-melted Si, which was pulled upward along the field. Consequently, the melted Si formed a sharper protrusion on solidification, with an apex surrounded by {001}, {113}, and {111} facets. The field emission from the protrusions was measured. The onset voltage of the emission from protrusions was lower when they were grown under the electric field. We used Fowler–Nordheim plots to characterize the emission current and voltage conversion factor, β. The results indicated that the application of electric field is beneficial to sharpening Si protrusions grown from Si melt. Such protrusions surrounded by facets are suitable for field emission electron sources with a high local electric field.

A light-detecting Ru(II)/Si heterojunction system involving a binuclear Ru (II) complex with pyridine-2,6-diimine (pydim) ligand

A meticulously detailed chemical procedure was employed to synthesize the Ru (II)-containing pyridine-2,6-diimine (pydim) organometallic complex. The resulting complex was then applied to Al-coated Si wafers using the spin-coating technique, leading to the production of Al/Ru(II) organometallic complex/n-Si/Al photodiodes. The light responsiveness of these photodiodes was demonstrated through the acquisition of I-V and I-t characteristics. Subsequently, essential parameters such as ideality factor, photosensitivity, barrier height, and photoresponse values were evaluated based on the obtained I-V and I-t plots. The calculations yielded ideality factors and barrier heights, resulting in average values of 6.41 and 0.552 eV, respectively. Furthermore, an in-depth analysis of the electrical properties of the diodes was conducted using G-V and C-V assessments, revealing a strong dependence on AC signal frequency. This investigation underscored that the observed frequency-related electrical behaviour is rooted in series resistance and interface states.

Nonvolatile bipolar resistive switching characteristics of aluminum oxide grown by thermal oxidation processes

This study proposes a bipolar resistive random-access memory (RRAM), which is fabricated using an aluminum oxide (AlO x ) resistive switching (RS) layer. The RRAM shows a large memory window of 106 at a low read voltage of 0.5 V. In addition, high switching speed, long retention time, and superior read-disturb immunity are observed. AlO x layers are prepared by a thermal oxidation growth process. Aluminum metal films deposited on n+-Si wafers are oxidized at O2/(O2 + N2) flow rate ratios of 50%–100%. Al/AlO x /n+-Si device shows no RS behavior when the AlO x is grown in a pure O2 environment. As the O2/(O2 + N2) flow rate ratio decreases to 50%, Al/AlO x :N/n+-Si device reveals stable bipolar RS characteristics. A filamentary mode based on oxygen interstitial and Al vacancy is proposed to explain the difference in electrical characteristics of AlO x devices prepared at different O2 flow rates.

High-performance CsPbBr3-silicon heterojunction photodetectors fabricated by chemical vapor deposition

Inorganic perovskite cesium lead halide (CsPbBr3) has attracted extensive research attention due to its excellent photoelectric properties and long-term stability to water, oxygen, light and heat. In this work, high crystallinity CsPbBr3 microcrystals with different morphologies and grain sizes were synthesized by one-step chemical vapor deposition (CVD) on silicon (Si) wafers and silicon nanowires (SiNWs), respectively. Characterization results show that the CsPbBr3 microcrystals grown on SiNWs (CsPbBr3-SiNWs) display more compact and uniform morphologies than those grown on Si wafer (CsPbBr3-Si). Moreover, CsPbBr3-SiNWs exhibits higher detectivity and larger on/off ratio than CsPbBr3-Si, which are 5.1 × 1012 Jones over 3.4 × 1012 Jones, and 51.3 over 14.7, respectively. Furthermore, CsPbBr3-SiNWs shows a faster photo response with a rise/fall time of 0.22 s/0.28 s than 0.26 s/0.32 s in CsPbBr3-Si. In addition, the CsPbBr3-SiNWs photodetector maintained 90% of its original photocurrent after 60 days of exposure to air, showing excellent stability. These results strongly suggest a promising fabrication approach for constructing perovskite-based heterojunction optoelectronic devices with high performance and excellent stability.

Aluminum-Based Plasmonic Photodetector for Sensing Applications

Plasmonic sensors have great potential for widespread usage. However, the prohibitive cost of noble metals restrains the wider adoption of these devices. The aim of our study is to develop a cost-effective Al-based alternative to common noble metal-based plasmonic detectors. We considered a structure consisting of an n-type doped Si wafer with a shallow p-n junction and an overlying Al grating with a trapezoidal groove profile. The RCWA (rigorous coupled-wave analysis) method was used to numerically calculate the distribution of absorbed light energy in the plasmonic detector layers and to optimize the grating parameters. Based on the simulation results, experimental samples of plasmonic photodetectors with optimal grating parameters (period—633 nm, relief depth—50 nm, groove filling factor—0.36, and thickness of the intermediate Al layer—14 nm) were manufactured, and their properties were studied. For these samples, we obtained a polarization sensitivity value of Ip/Is = 8, an FWHM of the resonance in the photocurrent spectrum ranging from 50 to 100 nm, a sensitivity at the resonance maximum of Iph = 0.04–0.06 A/W, and an angular half-width of photocurrent resonance of Δθ = 5°, which are comparable to noble metal-based analogs. Our results may be used for creating cost-effective high-sensitivity plasmonic sensors.

Surface enhanced Raman scattering in thin films: the importance of Raman analyte-plasmonic particle inverse geometry

Most of the successful applications of surface enhanced Raman scattering (SERS) involves placing the Raman analyte molecule over the SERS substrate. This conventional geometry of SERS does not work when the Raman analyte is in the form of a thin film. In this report, we experimentally demonstrate the importance of the rarely explored inverse geometry wherein a plasmonic particle is placed over an analyte thin film for SERS study. Initially, as a case study, the effect of size, concentration, and distribution of gold nanoparticles (AuNPs) on the SERS of Si wafer was performed. The AuNPs, prepared by optimized annealing of direct current sputtered Au, were characterized by scanning electron microscopy, atomic force microscopy, and UV-Visible spectrophotometry. Finally, as an application, SERS in inverse geometry was successfully performed with an electron-beam evaporated Si thin film. For the first time, a working formula has been proposed to determine the experimental enhancement factor (EEF) for the inverse geometry of SERS. The values of EEF were estimated to be 1526 and 3274 respectively for Si wafer and Si thin film for the similar distribution of AuNPs of average size 52 nm. This study provides an insight into the characterization of thin films.

Characterizing oxidation, thickness, and composition of metallic glass thin films with combined electron probe microanalysis and X-ray photoelectron spectroscopy

Metallic glass thin films (MGTFs) are a recently developed class of alloy coatings with potential applications ranging from biomedical devices to electrical components. Their tribological performance in service conditions is dictated by MGTF bulk composition but can be limited by the native oxide surface that inevitably forms upon exposure to atmosphere. Surface oxidation, thickness, and composition of ZrCuNiAl MGTFs were characterized using a combination of X-ray photoelectron microscopy (XPS) and electron probe microanalysis (EPMA). MGTF samples with nominal thicknesses of 50, 500, and 1500 nm were sputtered onto Si and SiN wafer substrates within a high vacuum deposition chamber and their amorphicity was confirmed by X-ray diffraction. XPS depth profiling identified the thin film composition and showed that the surface oxide was dominated by a mixed layer of mostly ZrO2, a little oxidized Al, and some metallic Zr. EPMA X-ray intensities were acquired as a function of beam energy to excite characteristic X-rays from different depths of the MGTFs and reconstructed using open-source thin film analysis software BadgerFilm, to determine the composition and thickness of sample layers. EPMA results constrain the composition to be Zr54Cu29Al10Ni7 within 0.7 at. % variation and total thicknesses to be 49, 470, and 1546 nm. Using the oxide composition identified from XPS depth profiling as an input for BadgerFilm analysis, EPMA results indicate the surface oxidation layer on each of the thin film samples was 6.5 ± 1.1 nm thick and uniform across a 0.25 mm region of the film.

Improvement of chemical mechanical polishing performance by introducing N–Si bond via external coating of cerium oxide with ZIF-8

Cerium oxide (CeO2) nanoparticles are widely used as abrasives in chemical mechanical polishing (CMP), an essential process for obtaining Si wafers with excellent surface quality. While CeO2 nanoparticles form Ce–O–Si bonds, which exhibit good CMP performance, their low activity results in a low removal rate. To address this issue, a two-step ultrasonic dispersion method was employed to prepare a uniform nuclear@shell CeO2@ZIF-8. The process of chemical bond generation in CMP was studied using spherical aberration-corrected transmission electron microscopy and X-ray photoelectron spectroscopy. In comparison to pure cerium oxide, the formation of Ce–O–Si bond was observed, and notably, the emergence of N–Si bond originating from the N of the ZIF-8 shell was identified. Coupled with the increased Ce3+ content, these developments enhanced CMP performance. The material removal rate (MRR) of the CeO2@ZIF-8 abrasives was 151.507 nm/min, which is 89.72 % higher than that of the pure CeO2 abrasives. Moreover, the surface roughness, as determined via AFM testing, was reduced to 0.231 nm within the confines of a 5.0 × 5.0 μm² region. Therefore, this study introduces a novel concept for CMP research by developing a CeO2@ZIF-8 compound abrasive to create a new N–Si bond.

Room Temperature Lattice Thermal Conductivity of GeSn Alloys.

CMOS-compatible materials for efficient energy harvesters at temperatures characteristic for on-chip operation and body temperature are the key ingredients for sustainable green computing and ultralow power Internet of Things applications. In this context, the lattice thermal conductivity (κ) of new group IV semiconductors, namely Ge1-xSnx alloys, are investigated. Layers featuring Sn contents up to 14 at.% are epitaxially grown by state-of-the-art chemical-vapor deposition on Ge buffered Si wafers. An abrupt decrease of the lattice thermal conductivity (κ) from 55 W/(m·K) for Ge to 4 W/(m·K) for Ge0.88Sn0.12 alloys is measured electrically by the differential 3ω-method. The thermal conductivity was verified to be independent of the layer thickness for strained relaxed alloys and confirms the Sn dependence observed by optical methods previously. The experimental κ values in conjunction with numerical estimations of the charge transport properties, able to capture the complex physics of this quasi-direct bandgap material system, are used to evaluate the thermoelectric figure of merit ZT for n- and p-type GeSn epitaxial layers. The results highlight the high potential of single-crystal GeSn alloys to achieve similar energy harvest capability as already present in SiGe alloys but in the 20 °C-100 °C temperature range where Si-compatible semiconductors are not available. This opens the possibility of monolithically integrated thermoelectric on the CMOS platform.

Facile fabrication of Au thin film substrates with crack-like nanogaps for surface-enhanced Raman spectroscopy

Surface-enhanced Raman spectroscopy (SERS) has the advantage of nondestructive, quick, and accurate detection of harmful substances. Among the methods used to fabricate SERS substrates, a conventional evaporation equipment can achieve nanostructure of various shapes and sizes by adjusting the process pressure. In this study, general thermal evaporation equipment was utilized to fabricate SERS substrates. Au thin films with nanogaps were deposited on bare Si wafers with different process pressures and film thicknesses to vary the shape and size of the nanogaps. The microstructure was observed through scanning electron microscopy and transmission electron microscopy. In addition, the contact angle and reflectance of the Au thin films were measured. As the process pressure increased, the light reflectance decreased and the contact angle of the film increased. The SERS effect was found to be influenced by the width, depth, and number of nanogaps, reflectivity, and contact angle of the thin films. Optimal performance was observed under a process pressure of 13.3 Pa and film thickness of 215 nm. Under these conditions, the 2 µM rhodamine 6 G, allura red AC, and sunset yellow FCF were detected, and the uniformity and reproducibility of the thin film were also confirmed over a 6-inch substrate.