Sputter Etching Research Articles

Effect of Bias Frequency on Bottom-Up SiO2 Gap-Filling Using Plasma-Enhanced Atomic Layer Deposition.

High-aspect-ratio patterns are required for next-generation three-dimensional (3D) semiconductor devices. However, it is challenging to eliminate voids and seams during gap-filling of these high-aspect-ratio patterns, such as deep trenches, especially for nanoscale high-aspect-ratio patterns. In this study, a SiO2 plasma-enhanced atomic layer deposition process incorporated with ion collision using bias power to the substrate was used for bottom-up trench gap-filling. The effect of bias power frequency on SiO2 trench gap-filling was then investigated. Results showed that changes in bias power frequency did not significantly change the process rate, such as SiO2 growth per cycle. At relatively low bias power frequencies, high-energy ions formed an overhang at the entrance of the high-aspect-ratio trench pattern through sputter etching and redeposition, blocking the pattern entrance. However, at relatively high-frequency bias power, overhang formation due to sputtering did not occur. In the trench interior, due to a scattering effect of ions, deposition was thicker at the bottom of the trench than that at the top, achieving bottom-up gap-filling and void-free gap-filling.

Nanoimprint Lithography for Next-Generation Carbon Nanotube-Based Devices.

This research reports the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors, and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nanoimprint lithography (NIL), magnetron sputtering, and reactive etching techniques was studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over an alumina support layer on a Si/SiO2 substrate. The metal particles were deposited using direct current (DC) magnetron sputtering technique, with a particle ranging from 6 nm to 12 nm and density from 70 to 1000 particles/micron. The Alumina layer was deposited by radio frequency (RF) and reactive pulsed DC sputtering, and the effect of sputtering parameters on surface roughness was studied. The pattern was developed by thermal NIL using Si master-molds with PMMA and NRX1025 polymers as thermal resists. Catalyst patterns of lines, dots, and holes ranging from 70 nm to 500 nm were produced and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Vertically aligned CNTs were successfully grown on patterned catalyst and their quality was evaluated by SEM and micro-Raman. The results confirm that the new fabrication process has the ability to control the size and shape of CNT arrays with superior quality.

An examination of the performance of molecular dynamics force fields: Silicon and silicon dioxide reactive ion etching

Classical molecular dynamics (MD) simulations of plasma-surface interactions were performed of physical sputtering and reactive ion etching (RIE), with predictions based on several force fields. In this paper, we focus mainly on SiO2 but include some results for Si substrates as well. We compare predictions from these MD simulations to experimental studies of SiO2 physical sputtering (by Ar+ ions), RIE of Si, and RIE of SiO2 (both using F atoms and Ar+ ions). MD results using different published force fields are compared to reported yields from published vacuum beam experiments. The near-surface depth profiles predicted using different force fields are compared. One motivation for the present study is to document the nature and magnitude of differences in the predictions for selected systems and conditions of practical interest.

Etched characteristics of nanoscale TiO2 using C4F8-based and BCl3-based gases

TiO2 is a material used in various fields such as electronics, optics, environment, etc. For the application to electronic and optical devices, TiO2 needs to be patterned using reactive ion etching using halogen-based gases. In this study, a TiO2 masked with ACL pillar pattern was etched using two types of gases namely C4F8-based (C4F8/SF6/Ar) and BCl3-based (BCl3/CF4/Ar), and the effect of etch gas and asynchronous pulsing (separated source power ON time and bias power ON time in a pulse period) on the etch properties such as the etch rates, etch selectivity, and aspect ratio dependent etching (ARDE) were investigated. The use of asynchronous pulsing with decreased bias pulsing ratio (high source power ON time and low bias ON time in a pulse period) improved the etch selectivity and ARDE possibly due to the lower sputter etching time after the removal of reacted species on the TiO2 surface and due to the more similar etch environment for different aspect ratio TiO2 features, respectively. The use of BCl3-based plasma showed higher etch selectivity over ACL compared to C4F8-based plasma, however, it showed the lower etch rate and more severe ARDE due to the stickiness of Cl compared to F to the sidewall during the etching of high aspect ratio TiO2.

Design and fabrication of energetic Al/Ni exploding foil with enhanced energy efficiency and plasma density for direct ignition

In order to lower the firing voltage, an energetic Al/Ni exploding foil (Al/Ni-EF) with enhanced energy efficiency and plasma density was prepared in this study, to realize the direct ignition of pyrotechnics. An Al/Ni reactive multilayer foil (Al/Ni-RMF) was firstly synthesized by magnetron sputtering and wet etch method, and its structure and exothermic behavior were investigated. Scanning Electron Microscopy, Atomic Force Microscope and X-ray Diffraction characterizations confirmed the periodic layer structure of Al/Ni-RMF with a total thickness of 4 μm. The highest heat release in Al/Ni-RMF could be achieved theoretically when the ratio of Al and Ni was 1.5, and thus the thickness of single Al and Ni layer was determined to be 300 nm and 200 nm, respectively. The obtained Al/Ni-RMF was subsequently fabricated to be an exploding foil, and its electric explosion performance was further studied. Energy efficiency of the Al/Ni-EF was measured to be 85.9% during the electric explosion process, which was 30.9% higher than that of Cu exploding foil (Cu-EF). The plasma generated at Al/Ni-EF had larger volume, longer duration time and higher temperature than Cu-EF due to the intermetallic reaction between Al and Ni, which was beneficial for the direct ignition of Boron/Potassium Nitrate composition (B/KNO3, BPN). Afterwards, a special Al/Ni-EF ignitor without slapper was constructed, and the fierce ignition of BPN at the minimum discharge voltage of 800 V was observed. Above results confirmed the feasibility of direct ignition, such a unique strategy was beneficial for the development of low-energy, low-cost and miniaturized ignitor.

Influence of Si surface preparation on CoSi2 formation and agglomeration

In microelectronics, despite a difficult nucleation of cobalt silicide CoSi2 in small dimensions, the CoSi2 based contacts remain interesting for some specific devices designed in 65 nm technology. Therefore, to promote the formation of CoSi2 in 65 nm technologies, it is possible to interfere on the formation of CoSi, that occurs during RTA1. To this end, the surface preparation of the Si substrate, before the Co deposition, may have an influence on the cobalt silicide phases formation. In this work, different surface preparations (SiCoNi, HF followed by SC1 and HF only), as well as several Soft Sputter Etch, SSE, processes have been applied on Si(100) wafers before the deposition of Co and TiN layers. Depending on the surface preparation, the formation temperatures and/or crystalline orientations for the Co silicide phases, including CoSi2, are different, as observed by XRD and/or EBSD. Four-point probes measurements also show a strong dependency of the CoSi2 agglomeration to the surface preparation scheme. These results highlight the influence of surface preparation on the Co silicides formation and agglomeration and its importance for the integration of CoSi2 films in a 65 nm CMOS technology.

An Efficient Design of the Piezoresistive Pressure Sensor Applied for Micro Aerial Vehicle

In this research, the developing process of a piezoresistive pressure sensor working in the atmosphere environment applied in micro aerial vehicle using the MEMS fabrication method is introduced. The sensor consists of four Au/Cr piezoresistors in a Wheatstone bridge configuration on a wet oxidized silicon diaphragm. To fabricate the sensor, three lithographic steps were conducted: the first one is to define the resistors and Au/Cr lines/pads, the second and the third ones are to determine the width and the thickness of the square SiO2/Si diaphragm, respectively. The sensor diaphragm shape and thickness were defined by the anisotropic etching of Si in tetramethylammonium hydroxide (TMAH) solution, and the resistors array are formed by sputtering and wet etching method. The sensor size is 6000 μm by 6000 μm. The sensor output voltage was measured for various applied pressure levels from -0.9to 1.2 bar with 5V voltage supply. The fabricated pressure sensor also exhibits a sensitivity of 50.1 mV/bar

A Parylene-Based Ultra-Thin Printed Circuit Board As a New Platform for Flexible Sensors and Wearables

Flexible electronics and sensors are a key enabling element for the realization of wearables and geometry adaptive devices needed to follow current trends such as the Internet of things or Industry 4.0. Within this paper, we present a new and flexible packaging platform by the fabrication of an ultra-thin and highly flexible printed circuit board (PCB).The thermoplastic polymer Parylene, which combines a variety of unique properties such as optical transparency, biostability and biocompatibility according to ISO 10993, thermal stability as well as low permeability for gases and water, was used as the base for the new PCB.Particularly, its mechanical properties, especially the absence of intrinsic stresses, as well as its low Young’s modulus and good bendability are advantageous when using Parylene films as a free-standing substrate for flexible applications. The chemical inertness of Parylene against all common acids, bases and solvents ensures its compatibility with established standard microsystem technologies.For the realization of ultra-thin flexible PCBs, Parylene was used as a substrate as well as for the encapsulation and protection layer, respectively. Furthermore, Parylene was the dielectric between the metallic conductive layers. These redistribution layers (RDL) were deposited and patterned by standard microsystem technologies, such as sputtering, lithography and wet chemical etching. Hence, structure sizes of down to 10 µm were successfully realized. Different metals, such as gold, copper, and aluminum were tested for the RDL. Alternatively, printing technologies such as screen printing and aerosol jet printing were successfully demonstrated for the if conductive silver layerse. The electrical connection between the various RDL was of special interest throughout the study and was realized by etching vertical vias through the Parylene using oxygen plasma. Due to the low total thickness of the flexible Parylene PCB of 20 µm or even less, the obtained vias through the Parylene feature an advantageous low aspect ratio. For the contact formation through the vias, different methods were investigated, e. g. sputtering, printing and electrochemical deposition.Finally, the fabricated flexible Parylene PCB were characterized with respect to their bendability and electrical properties. Doing so, the resistivity and capacitance were measured as well as the frequency response between 20 kHz and 500 MHz. Particularly, for frequencies below 1 MHz the realized flexible Parylene PCBs show a good electrical performance.A third function of Parylene with respect to the realization of an ultra-thin and flexible PCB is its usage as a barrier or capping layer. Doing so, new approaches such as embedding electronic or sensor components in the flexible PCB can be enabled. Other integration technologies such as wire bonding, printing or gluing were investigated with respect to their usability for the new flexible PCB as well. Besides, also the direct fabrication of sensors on the Parylene flexible PCB was successfully demonstrated by the realization of a flexible potentiometric pH sensor.The presented new type of ultra-thin PCB is a versatile platform for the realization of flexible electronics, sensors and devices. Due to its biocompatible properties, the flexible Parylene PCB can be used for medical applications but also for the integration of MEMS, chemical sensors and optical components, respectively. Doing so, it enables the realization of smart systems for wearable applications and their integration into light weight constructions. Within this paper, the concept of this new approach, the respected fabrication and integration technologies as well as possible applications are presented in detail. Figure 1

Low-Temperature Deposition of High-Quality SiO2 Films with a Sloped Sidewall Profile for Vertical Step Coverage

SiO2 is one of the most widely used dielectric materials in optical and electronic devices. The Josephson voltage standard (JVS) chip fabrication process has rigorous requirements for the deposition temperature and step-coverage profiles of the SiO2 insulation layer. In this study, we deposited high-quality SiO2 insulation films at 60 °C using inductively coupled plasma-chemical vapor deposition (ICP-CVD) to fulfill these requirements and fabricate JVS chips simultaneously. SiO2 films have a high density, low compressive stress, and a sloped sidewall profile over the vertical junction steps. The sidewall profiles over the vertical junction steps can be adjusted by changing the radio frequency (RF) power, ICP power, and chamber pressure. The effects of sputtering etch and sloped step coverage were enhanced when the RF power was increased. The anisotropy ratio of the deposition rate between the sidewall and the bottom of the film was lower, and the sloped step coverage effect was enhanced when the ICP power was increased, or the deposition pressure was decreased. The effects of the RF power on the stress, density, roughness, and breakdown voltage of the SiO2 films were also investigated. Despite increased compressive stress with increasing RF power, the film stress was still low and within acceptable limits in the device. The films deposited under optimized conditions exhibited improved densities in the Fourier transform infrared spectra, buffered oxide etch rate, and breakdown voltage measurements compared with the films deposited without RF power. The roughness of the film also decreased. The step-coverage profile of the insulation layer prepared under optimized conditions was enhanced in the junction and bottom electrode regions; additionally, the performance of the device was optimized. This study holds immense significance for increasing the number of junctions in future devices.

Fluoropolymer Passivation Enhanced Switching Endurance of MoS2 Memristors

The advances in computing and mobile devices have realized massive generation, collection, and processing of data. The concept "Internet of things" and "Big data" have necessiated large-scale parallel processing, as computing of collected data is highly dependent on matrix multiplication process, which in inherently parallel.In this context, conventional machines are exhibiting their limits as they are unsuited for parallel processing, resulting in low performance and high power consumption [1]. The need for advances in parallel processing hardware is emerging.In this regard, memristors have gathered attention for their high potentials as parallel processing units. There have been reports of memristors with high on/off ratio, fine retention, high switching enderance, and fast switching spped, etc [2-4]. Memristor is a non-volatile memory which stores data as internal resistance, modulated by applied voltage. Even though memristors contain high capabilities for parallel processing, scaling of devices still remain as a challenge. Conventional materials have their limit for both lateral and vertical scaling.To achieve a major breakthrough, we have fabricated memristors based on 2D materials with atomic-scale thickness of ~ 7 nm [5]. As surface-to-volume ratio is high in 2D materials, they are chemically active, leading to susceptible properties to external environment and instability in fabricated devices with 2D materials. To compensate the drawback, we applied fluoropolymer passivation layer and obtained stable switching endurance for 100 potentiation & depression cycles with 25 states.For device fabrication, we used direct current sputtering & wet etching to pattern bottom Au/Cr (50/5 nm) electrodes. Molybdenum disulfide flakes were mechanically exfoliated from bulk mineral and dry-transferred onto bottom electrodes by PDMS (Polydimethylsiloxane) stamps. Top electrodes were patterned by photolithography & evaporation of Ni/Au (5/100 nm).With the introduction of 2D materials to next-generation electronics, memristors can be even more revolutionized towards extreme scaling of devices. By compensating susceptibility in the material itself and studying degradation mechanism, parallel computing would be realized away from power-plugged environment, and accelerate artificial intelligence in our everyday lives. Figure Caption Fig 1. Electrical characterization of the resistive switching MoS2 memristor with non-volatile memory behavior. (a) Semi-log plots of IV curve, resistive switching triggered by voltage sweeping. Inset: False-color SEM image of a fabricated device; scale bar: 4μm. (b) Scheme for pulse voltages (top), potentiation and depression of conductance states (bottom). (c) Encapsulation-enhanced switching stability of MoS2 memristors. Detailed illustration of 20 PD cycles in CYTOP-encapsulated (top) and bare devices (bottom).

Preparation of Waterproof and Breathable Polyethylene (PE) Film Through One-Step Plasma Treatment

The waterproof and breathable multifunctional films have been widely used in advanced wear protection, medical treatment, monitoring, and the aerospace industry. In this research, we prepared a new class/kind of waterproof and breathable intelligent (WBI) films through plasma surface treatment, which can be applied in the health care field. After air plasma treatments, the structural properties of polyethylene (PE) film were observed by Scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), Thermogravimetry (TG), and Differential scanning calorimetry (DSC). It was found that plasma treatment etches PE fibers due to the sputter etching effect of plasma modification, leading to a crystallinity decrease. In addition, the changes in water contact angle, air permeability, and water vapor transmission rate of PE films were measured to illustrate their waterproof and breathable properties. After plasma treatment, the water contact angle of PE film reduced from 112.67∘ to 45∘, indicating the PE surface converted from hydrophobic into hydrophilic. The air permeability increased to 0.450[Formula: see text]mm/s and the water vapor transmission rate increased to 1419.788[Formula: see text]g/m[Formula: see text], which means the treated PE films are breathable but not permeable to liquid water. The improved performance in waterproof and breathability expands the application of PE film in the pharmaceutical field.

In situ and ex situ processes for synthesizing metal multilayers with electronically conductive interfaces

A number of technological applications and scientific experiments require processes for preparing metal multilayers with electronically and thermally conductive interfaces. We investigate how in situ vs ex situ synthesis processes affect the thermal conductance of metal/metal interfaces. We use time-domain thermoreflectance experiments to study thermal transport in Au/Fe, Al/Cu, and Cu/Pt bilayer samples. We quantify the effect of exposing the bottom metal layer to an ambient environment prior to deposition of the top metal layer. We observe that for Au/Fe, exposure of the Fe layer to air before depositing the top Au layer significantly impedes interfacial electronic currents. Exposing Cu to air prior to depositing an Al layer effectively eliminates interfacial electronic heat currents between the two metal layers. Exposure to air appears to have no effect on interfacial transport in the Cu/Pt system. Finally, we show that a short RF sputter etch of the bottom layer surface is sufficient to ensure a thermally and electronically conductive metal/metal interface in all materials we study. We analyze our results with a two-temperature model and bound the electronic interface conductance for the nine samples we study. Our findings have applications for thin-film synthesis and advance fundamental understanding of electronic thermal conductance at different types of interfaces between metals.

Study of the Pattern Preparation and Performance of the Resistance Grid of Thin-Film Strain Sensors.

The thin-film strain sensor is a cutting-force sensor that can be integrated with cutting tools. The quality of the alloy film strain layer resistance grid plays an important role in the performance of the sensor. In this paper, the two film patterning processes of photolithography magnetron sputtering and photolithography ion beam etching are compared, and the effects of the geometric size of the thin-film resistance grid on the resistance value and resistance strain coefficient of the thin film are compared and analyzed. Through orthogonal experiments of incident angle, argon flow rate, and substrate negative bias in the ion beam etching process parameters, the effects of the process parameters on photoresist stripping quality, etching rate, surface roughness, and resistivity are discussed. The effects of process parameters on etching rate, surface roughness, and resistivity are analyzed by the range method. The effect of substrate temperature on the preparation of Ni Cr alloy films is observed by scanning electron microscope. The surface morphology of the films before and after ion beam etching is observed by atomic force microscope. The influence of the lithography process on the surface quality of the film is discussed, and the etching process parameters are optimized.

Effect of target grain size on target sputter etching morphology and performance

In this paper, three large scalar high-purity solid copper targets with different grain sizes are sputtered under the same experimental conditions. The sputter etching mechanism of grains on the target surface and the influence of target grain size on the sputter etching morphology were observed. Moreover, the target voltage of the three targets has also been measured. The results reveal that the sputtering of the grain on the target surface is extending from the grain boundary to the grain interior. Targets with different grain sizes show different target voltages depending on the sputter etching morphology. The target with a small grain size has a uniform and dense morphology with connected pits and bulges and a slight “black slump.” This morphology renders a higher target voltage than ones with larger grain sizes, which is due to the recapture of secondary electrons on the surface of the target.

Room temperature bonding of GaN and diamond substrates via atomic layer

GaN and diamond substrates were bonded at room temperature with an atomically thin bonding layer. This entailed sputter etching the surface of the GaN substrate in the bonding machine to expose the active nascent GaN surface. At the same time, rather than using sputter etching, a ∼1 nm-thick Si nano-adhesion layer was deposited on the diamond surface. The advantage of this newly developed approach is that it suppresses the physical damage typically inflicted upon the diamond crystals by sputtering. This restricts the thickness of the amorphous layer at the GaN/diamond bonding interface to less than 2 nm. The proposed GaN/diamond integration is expected to contribute to efficient heat dissipation and facilitate the high-power and high-frequency operation of GaN devices.

A comparative study of the effect of different surface treatments on polymeric substrates

In this work, we investigated the effect of three surface treatments on the properties of polymethyl methacrylate (PMMA) and polycarbonate (PC). The treatments consisted of ultraviolet-ozone, sputter etching and oxygen plasma. Their effect on the adhesion between a vacuum deposited TiO2 coating and the substrate were also assessed by cross-cut test. Detailed characterization of the optical properties, surface wettability, morphology and the chemical composition of the surface after the treatments was performed for the test samples. Reference samples without any surface treatment were also used for comparison purposes. Optical transmittance of the samples was not significantly altered by the surface treatments. Only the presence of the coating led to an increase of the system refractive index and to a small decrease of the light transmittance. All surface treatments lead to an increase of oxygen species in polymer surface, which rise the wettability. In particular, the ultraviolet-ozone treatment shows a higher change in the oxygen/carbon ratio, resulting however in the weakest adhesion between the coating and substrate, due to the generation of low molecular weight compounds weakly bonded to the surface. Furthermore, regardless of the surface treatment employed, the PMMA substrate presented lower film adhesion than PC.

A combination of ion beam sputtering and in situ x-ray diffraction as a method for depth-resolved phase analysis using nitrogen-implanted austenitic stainless steel as an example

In situ x-ray diffraction (XRD) during ion implantation or thin film deposition is a powerful method to follow the time evolution of diffusion and phase transition processes in thin films, even as the depth resolution is still dominated by the information depth of the x rays. However, in the case of sputter etching with energetic ions at moderate temperatures, where no diffusion or phase transformation processes are active, this limitation is no longer of concern. Here, thin surface layers which are removed by sputtering can be identified with a depth resolution of 25 nm or better—while information from the substrate—despite overlayers of several micrometers—is accessible. However, considerable mathematical operations are necessary to convert the time series of diffractograms measured by XRD into a depth series. In this paper, a method is highlighted describing which depth-resolved properties of thin films can be accessed using such in situ measurements during ion beam sputtering in the model system austenitic stainless steel + nitrogen: (i) the influence of concentration gradients on the peak shape and peak width for conventional XRD scans in Bragg–Brentano geometry is determined; (ii) correlations between the local nitrogen concentration and the local lattice expansion can be established; and (iii) the evolution of the scattering intensity with depth becomes accessible, thus depth-resolved information on defect densities or grain size (normal to the surface) can be extracted without resorting to transmission or scanning electron microscopy.

Enhancement of Gripping Ability for Soft and Slippery Objects by Using Double-Scale Protrusions

Enhancement of surface friction is an important problem for many machine parts and instruments designed to grip or convey soft bodies and sheets. This paper presents an approach to increase gripping ability for soft and slippery objects by using double-scale protrusions: One is millimeter-sized protrusions on a SUS420J2 stainless steel produced by electrical discharge machining and another is micrometer-sized fine protrusions formed by sputter etching. The friction tests of a soft silicone sheet proved that the double-scale protrusions have higher gripping ability than single-scale protrusions in an oil environment.

Development of robust amphiphobic hierarchical structure on polymer substrate by thermal imprinting and sputter etching

Amphiphobic surfaces are found in many natural organisms for protection from external contamination because they can repel both water and oil. The development of an amphiphobic surface is based on the construction of hierarchical structures and chemical modification. In this study, thermal imprinting and sputter etching were conducted to create a micropillar array and nano-protrusions to form a hierarchical structure. Different hierarchical structures were developed by using different nickel stamps and upon varying the etching time. These structures were modified using an environment-friendly drysurf (G993G3, Harves) solution through a spraying method. The surface presented high repellency toward various liquid droplets with surface tensions ranging from 72 to 22 mN m −1 , with contact angles of 158° for water and 120° for hexadecane. The surface showed good self-cleaning performance without any traces of water droplets or glass bead particles. In addition, various tests including sand abrasion , bending, and immersion tests were conducted to evaluate the mechanical and chemical robustness of the hierarchical structure, which exhibited good performance. Hierarchical structures with these excellent properties are expected to be widely applied in surface waterproofing, antifouling, and self-cleaning treatments. • Micropillars with appropriate size are required to create hierarchical structure. • Net-like nanoprotrusions are fabricated on micropillars by sputter etching. • Hierarchical micro/nanostructure shows better amphiphobicity than micropillars. • The amphiphobic surface presents good chemical stability and mechanical robustness. • The amphiphobic surface can be applied as antifouling and self-cleaning materials.

ICMCTF 2021 – Preface

Amphiphobic surfaces are found in many natural organisms for protection from external contamination because they can repel both water and oil. The development of an amphiphobic surface is based on the construction of hierarchical structures and chemical modification. In this study, thermal imprinting and sputter etching were conducted to create a micropillar array and nano-protrusions to form a hierarchical structure. Different hierarchical structures were developed by using different nickel stamps and upon varying the etching time. These structures were modified using an environment-friendly drysurf (G993G3, Harves) solution through a spraying method. The surface presented high repellency toward various liquid droplets with surface tensions ranging from 72 to 22 mN m−1, with contact angles of 158° for water and 120° for hexadecane. The surface showed good self-cleaning performance without any traces of water droplets or glass bead particles. In addition, various tests including sand abrasion, bending, and immersion tests were conducted to evaluate the mechanical and chemical robustness of the hierarchical structure, which exhibited good performance. Hierarchical structures with these excellent properties are expected to be widely applied in surface waterproofing, antifouling, and self-cleaning treatments.