Article
Engineering, Mechanical
Qixiang Zhang, Jisheng Pan, Xiaowei Zhang, Jiabin Lu, Qiusheng Yan
Summary: This study evaluated the effect of different polishing slurries on single crystal 6H-SiC friction and wear, showing that the SiC surface only had scratches when silica sol abrasive was present, and a loose and porous chemical reaction layer formed when oxidant was present.
Article
Materials Science, Ceramics
Xiaozhe Yang, Xu Yang, Haiyang Gu, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: This paper proposes a slurryless, highly efficient polishing method called ultrasonic vibration assisted electrochemical mechanical polishing (UAECMP) for achieving subnanometer surface roughness on 4H-SiC wafers. The performance of UAECMP was evaluated and compared to ordinary electrochemical mechanical polishing and mechanical polishing. The results showed that UAECMP achieved a significantly higher material removal rate and that ultrasonic vibration played a crucial role in increasing the anodic oxidation rate. However, increasing the ultrasonic vibration amplitude also led to an increase in surface roughness, suggesting the need for a combined UAECMP and ECMP process.
CERAMICS INTERNATIONAL
(2022)
Article
Instruments & Instrumentation
Da Hu, Huilong Li, Jiabin Lu, Qiusheng Yan, Qiang Xiong, Zhanliang Huang, Fenglin Zhang
Summary: Magnetorheological elastomers are intelligent controllable materials used in chemical mechanical polishing. The magnetic particles in the polishing pad act as solid-phase catalysts for oxidizing SiC surfaces, reducing processing difficulty and improving surface quality.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Chemistry, Physical
Huan Chen, Chaoyang Wei, Zhen Cao, Xiaocong Peng, Zhigang Jiang, Songlin Wan, Jianda Shao
Summary: In order to improve the polishing efficiency of RB-SiC substrates, a simple laser pretreatment process was demonstrated using femtosecond laser to modify the RB-SiC surface pre-coated with silicon powder. The pre-coated surface was oxidized under femtosecond laser irradiation, gradually forming a modified layer that bonded tightly to the RB-SiC substrate. By optimizing the laser scanning parameters, a high-quality modified layer with stronger adhesion strength could be obtained. This approach increased the polishing efficiency over 3 times and can be applied to more complex RB-SiC surfaces.
APPLIED SURFACE SCIENCE
(2023)
Article
Engineering, Electrical & Electronic
Peixuan Ji, Kaimin Zhang, Zhenzhen Zhang, Mei Zhao, Rui Li, Danni Hao, Ramiro Moro, Yanqing Ma, Lei Ma
Summary: SiC is crucial for the epitaxial growth of graphene and shows potential as an ideal material for future high power electronics. The electronic properties of graphene depend greatly on the growth facet. The selection of facet allows for tuning the desired characteristics. Achieving atomically smooth SiC wafers is a key factor for growing pristine graphene on them. In this study, the grinding, mechanical polishing, and chemical mechanical polishing (CMP) procedures applied to SiC wafers with arbitrary facets are explored through a data-driven approach. The polishing steps, phenomena, and principles are discussed. Different recipes are required for the C and Si faces of SiC due to their unique atomic arrangements. The rarely studied (1 1 05) facet is taken as an example to demonstrate the procedures for non-polar cases. The material removal rate (MRR) in mechanical polishing is directly influenced by the facet hardness. The MRR of the (1 1 05) facet is the slowest in this process, but it is 18 times faster than the Si-face during CMP, indicating different polishing mechanisms. Proposed polishing recipes can be adjusted to create atomically smooth wafers of any SiC facet.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Engineering, Manufacturing
Liqing Qiao, Liwei Ou, Kang Shi
Summary: An efficient wireless photoelectrochemical mechanical polishing (WPECMP) method was proposed based on the mechanism of bipolar photoelectrochemistry, which applies a wireless electric field to separate photogenerated electron-hole pairs during polishing. The WPECMP method enables wafers to achieve a damage-free surface/subsurface, with a lower surface roughness and higher surface flatness compared to the CMP technology.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Electrochemistry
Chao Zhang, Ping Zhou, Ying Yan, Dongming Guo
Summary: A new method called solid-liquid electrolyte electrochemical polishing (SL-ECP) is proposed in this study, using a solid electrolyte polishing pad to reduce low-spatial-frequency errors and achieve high-quality polished surfaces.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Shang Gao, Honggang Li, Han Huang, Renke Kang
Summary: In this study, the morphologies and damage patterns of ground and lapped silicon surfaces were compared, showing that the lapped surface had a softer damage layer and a higher bearing area ratio, resulting in a lower material removal rate.
APPLIED SURFACE SCIENCE
(2022)
Article
Automation & Control Systems
Mingpu Xue, Wen Xiao, Tianyi Zhang, Zhankui Wang, Jianxiu Su
Summary: A dry-type tribochemical mechanical polishing (DTCMP) method was proposed to solve the problems of low efficiency, high cost, and environmental pollution in the chemical mechanical polishing (CMP) process of single crystal SiC substrates. Catalysts were added to enhance its efficiency, and the mechanism of catalyst action was investigated.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Automation & Control Systems
Hsien-Kuang Liu, Chao-Chang A. Chen, Ping-Chun Hsieh
Summary: This study develops an innovative G-slurry for efficient CMP of 4H-SiC wafers. The G-slurry, fabricated by chemically grafting PU/GO and SiO2 abrasives, shows strong bonding and improved performance in surface roughness and improvement rate. The G-slurry is potentially applicable in SiC wafer processing.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Chemistry, Physical
Yi Zhang, Yongjie Zhang, Kaixuan Gu, Linfeng Zhang, Yuanmin Zhu, Dianzi Liu, Hui Deng
Summary: The advancement of science and technology has led to improved manufacturing precision. This study introduces a method to efficiently fabricate large-scale atomically flat surfaces and achieve high polishing efficiency. The method holds potential for mass-producing atomic-scale smooth surfaces and promoting innovation in advanced technologies.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Tingkai Yang, Changhua Liu, Tao Chen, Meng Shao, Chun Jiang, Changzheng Lu, Shijun Song
Summary: Reaction-bonded silicon carbide (RB-SiC) is a promising material for large lightweight ground-based space telescopes due to its superior mechanical properties. This study proposes a femtosecond laser-based polishing method for RB-SiC to enhance surface quality. The feasibility of femtosecond laser polishing is verified through the analysis of ablation types and calculation of the single-pulse ablation threshold. By conducting experiments and selecting optimal parameters, the polishing efficiency is improved, potentially replacing intermediate steps of traditional mechanical polishing.
Article
Chemistry, Physical
Linfeng Zhang, Bing Wu, Yi Zhang, Hui Deng
Summary: Plasma-based atom-selective etching (PASE) is used to efficiently planarize the GaN surface. Non-toxic carbon tetrafluoride is chosen as the reaction gas for PASE, which improves the volatility of etching products. PASE of GaN reduces surface roughness from Sa 135.8 nm to Sa 0.527 nm in 2 minutes, with a material removal rate 93.01 μm/min, thousands of times higher than the conventional chemical mechanical polishing method. The crystal structure of the GaN subsurface remains intact, proving the non-destructive nature of PASE. Furthermore, the effects of radio frequency power and reaction gas flow rate on PASE are investigated.
APPLIED SURFACE SCIENCE
(2023)
Review
Chemistry, Multidisciplinary
Wantang Wang, Xuesong Lu, Xinke Wu, Yiqiang Zhang, Rong Wang, Deren Yang, Xiaodong Pi
Summary: 4H silicon carbide (4H-SiC) is a promising material for high-power and high-frequency electronics, and high-quality 4H-SiC wafers with planarization are crucial for their performance. Chemical-mechanical polishing (CMP) is the key technology for planarization of 4H-SiC wafers. This review introduces the properties of 4H-SiC and the processing of its wafers. The development of CMP with chemical, mechanical, and chemical-mechanical synergistic approaches to enhance its performance is systematically reviewed. The prospect of these improvement approaches is provided by comparing CMP's material removal rate and surface roughness of 4H-SiC wafers.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Physical
Yang Lei, Ming Feng, Ke Wu, Jinxi Chen, Jianghao Ji, Julong Yuan
Summary: Single-crystal sapphire is an important material widely used in various advanced fields. The semi-fixed abrasive grain processing method has been developed as a prominent technique for achieving ultra-precision damage-free surfaces. This study aimed to investigate the characteristics and optimization of the semi-fixed abrasive grains polishing tool for sapphire by analyzing the influence of different parameters on surface roughness and material removal rates. The results showed that external load had the greatest impact on surface roughness and material removal rate, followed by abrasive particle size. By mixing abrasive particle sizes, it was possible to reduce the difficulty in manufacturing the polishing tool. The polishing tool with 200 nm and 1 μm particle sizes performed the best in the first 210 minutes of polishing.
Article
Engineering, Industrial
Rongyan Sun, Xu Yang, Kenta Arima, Kentaro Kawai, Kazuya Yamamura
CIRP ANNALS-MANUFACTURING TECHNOLOGY
(2020)
Article
Instruments & Instrumentation
Daisetsu Toh, Pho Van Bui, Ai Isohashi, Satoshi Matsuyama, Kazuto Yamauchi, Yasuhisa Sano
REVIEW OF SCIENTIFIC INSTRUMENTS
(2020)
Article
Materials Science, Multidisciplinary
Yasuhisa Sano, Koki Tajiri, Yuki Inoue, Risa Mukai, Yuma Nakanishi, Satoshi Matsuyama, Kazuto Yamauchi
Summary: Plasma etching with high-pressure SF6 plasma is proposed as a method for thinning SiC wafers without crystallographic damages. The removal rate is primarily influenced by power density and relatively unaffected by parameters such as processing gap and gas flow rate. An increase in radio frequency power can achieve high-speed etching of SiC wafers, with the potential to thin a 2-inch wafer to approximately 100 mu m in just 20 minutes.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Physical
Xiaozhe Yang, Xu Yang, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: The study investigated factors affecting the anodic oxidation rate of SiC and found that electrolyte temperature, surface damage, doping concentration, and strain all have a promotional effect on SiC anodic oxidation. The relationship between strain on the SiC surface and anodic oxidation rate was quantitatively studied by a strain-controllable anodic oxidation device, showing that both compressive and tensile strains increase the anodic oxidation rate of SiC. The study is expected to guide the improvement of ECMP efficiency and contribute to its practical application.
APPLIED SURFACE SCIENCE
(2021)
Article
Optics
Satoshi Matsuyama, Hiroyuki Yamaguchi, Takato Inoue, Yuka Nishioka, Jumpei Yamada, Yasuhisa Sano, Yoshiki Kohmura, Makina Yabashi, Tetsuya Ishikawa, Kazuto Yamauchi
Summary: The extended X-ray adaptive zoom condenser system can adjust its numerical aperture by controlling mirror surfaces, allowing for variation in beam size without moving the light source, mirrors, or final focus. A feasibility test conducted at SPring-8 demonstrated that the beam size can be varied between 134 and 1010 nm, showing promising results.
Article
Materials Science, Multidisciplinary
Nian Liu, Hideaki Yamada, Naoya Yoshitaka, Kentaro Sugimoto, Rongyan Sun, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: The study found that mechanical polishing resulted in surface and subsurface damage on mosaic single-crystal diamond, while plasma-assisted polishing successfully removed such damage. These differences were observed through various measurements like scanning white-light interferometer, scanning cathodoluminescence, and MicroRaman spectroscopy.
DIAMOND AND RELATED MATERIALS
(2021)
Article
Electrochemistry
Xiaozhe Yang, Xu Yang, Haiyang Gu, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: Slurryless electrochemical mechanical polishing is effective for polishing SiC wafers, but the charge utilization efficiency needs to be controlled within a certain range to avoid significant reduction in material removal rate.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Engineering, Multidisciplinary
Rongyan Sun, Atsunori Nozoe, Junji Nagahashi, Kenta Arima, Kentaro Kawai, Kazuya Yamamura
Summary: The self-sharpening of fixed abrasive grinding stones has limitations. A novel dress-free dry polishing process combining plasma-assisted polishing and plasma-assisted dressing has been proposed for high integrity polishing with constant exposure of new abrasives and increased material removal rate (MRR).
PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY
(2021)
Article
Instruments & Instrumentation
Takato Inoue, Yuka Nishioka, Satoshi Matsuyama, Junki Sonoyama, Kazuteru Akiyama, Hiroki Nakamori, Yoshio Ichii, Yasuhisa Sano, Xianbo Shi, Deming Shu, Max D. Wyman, Ross Harder, Yoshiki Kohmura, Makina Yabashi, Lahsen Assoufid, Tetsuya Ishikawa, Kazuto Yamauchi
Summary: A hybrid deformable x-ray mirror has been developed, utilizing two bending mechanisms to contribute to the mirror shape formation and minimize the voltage distribution amplitude of the bimorph mirror for stable operation.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Instruments & Instrumentation
Yasuhisa Sano, Ken Nishida, Ryohei Asada, Shinya Okayama, Daisetsu Toh, Satoshi Matsuyama, Kazuto Yamauchi
Summary: The deterministic processing method is a high-precision finishing method that achieves nanometer-scale accuracy but with low productivity. By using a novel intermittent gas flow system and an array-type plasma generator, uniform removal of material can be achieved efficiently.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Engineering, Manufacturing
Xu Yang, Xiaozhe Yang, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: The study proposes a three-step silicon carbide wafer manufacturing process using slurryless electrochemical mechanical polishing, which can rapidly transform an unprocessed SiC wafer to an atomically smooth surface, thereby reducing the cost and manpower required during SiC wafer manufacturing.
JOURNAL OF MANUFACTURING PROCESSES
(2021)
Article
Materials Science, Ceramics
Xiaozhe Yang, Xu Yang, Haiyang Gu, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: This paper proposes a slurryless, highly efficient polishing method called ultrasonic vibration assisted electrochemical mechanical polishing (UAECMP) for achieving subnanometer surface roughness on 4H-SiC wafers. The performance of UAECMP was evaluated and compared to ordinary electrochemical mechanical polishing and mechanical polishing. The results showed that UAECMP achieved a significantly higher material removal rate and that ultrasonic vibration played a crucial role in increasing the anodic oxidation rate. However, increasing the ultrasonic vibration amplitude also led to an increase in surface roughness, suggesting the need for a combined UAECMP and ECMP process.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Nian Liu, Kentaro Sugimoto, Naoya Yoshitaka, Hideaki Yamada, Rongyan Sun, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
Summary: This study systematically investigates the effects of polishing pressure and sliding speed in plasma-assisted polishing (PAP) on single crystal diamond (SCD) substrates. The results show that low polishing pressures lead to a smooth atomic-scale surface, while high pressures result in a rough surface with grooves. Furthermore, the sliding speed has minimal effect on the surface quality parameter.
DIAMOND AND RELATED MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Junhuan Li, Shaoxian Li, Tomoki Higashi, Kentaro Kawai, Kouji Inagaki, Kazuya Yamamura, Kenta Arima
Summary: The study observed a quadrangle lattice resembling a rectangle on a graphene nanosheet on graphite, possibly originating from the unique structure and electron distribution of AGNRs. Wrinkles and adsorbates in graphene play a role similar to an armchair edge, affecting electronic structures.
Article
Multidisciplinary Sciences
Nian Liu, Kohki Sugawara, Naoya Yoshitaka, Hideaki Yamada, Daisuke Takeuchi, Yuko Akabane, Kenichi Fujino, Kentaro Kawai, Kenta Arima, Kazuya Yamamura
SCIENTIFIC REPORTS
(2020)
