エレクトロニクス産業を支えるナノメートルオーダーの計測、分析、加工を実現する半導体デバイス製造検査装置技術の研究開発を推進しています。とくに電子顕微鏡の性能向上に向けた電子源や電子光学系などの要素技術と計測アプリケーション、プラズマ/ドライプロセスを用いた微細加工技術やプロセス装置開発、また半導体/新材料等における分析技術を活用したプロセス/マテリアルズインフォマティクスなどの応用技術が研究対象です。さらに半導体製造などの精密製造分野では省人化や生産性向上にむけた装置制御技術のニーズが高まり、とくにAI/機械学習の活用と物理/ハードウェア知識に基づくデータ解析技術と高精度な装置制御技術も並行して開発を推進しています。
電子顕微鏡、計測/分析/分光技術、微細加工、プラズマ/ドライプロセス、マテリアルインフォマティクス
デジタルツイン、AI、機械学習、画像認識/処理、特徴量抽出、装置運用/管理、レシピ/処理条件
Publishing Academic Papers:
D.Bizen, et al., Observing secondary-electron yield and charging in an insulating material by ultralow-voltage scanning electron microscope
JVST B 40, 012805 (2022)
https://doi.org/10.1116/6.0001465
ABSTRACT: Secondary-electron yield (SEY) and surface charging of various insulating materials under irradiation of primary electrons (PEs) with energy of lower than 100 eV were investigated. Irradiation energy of the PEs with SEY of 1 (E1) for SiO2 and Si3N4 was about 20 eV and that for the resist using in extreme ultraviolet (EUV) lithography was about 40 eV. Additionally, it was found that E1 corresponds to the lower limit for obtaining scanning electron microscope images of the EUV resist pattern. The surface potential of the pattered EUV resist modulated by PE irradiation was estimated by using a retarding-field energy filter. It was found that the surface potential varies with the width and pitch of the EUV resist pattern. The variation of surface potential depends on the width and pitch due to the fact that the secondary electrons emitted from the space of the resist pattern are absorbed in the sidewalls of the resist pattern as it becomes denser.
S.Matsunaga, et al.,Diffusion of zirconium on the surface of Schottky electron sources
JVST B39, 062806 (2021)
https://doi.org/10.1116/6.0001381
ABSTRACT: The current study investigates the diffusion of a Zr–O complex on a W substrate, which is one of the surface components of the Schottky electron source. To enable the thermal diffusion of Zr atoms with the assistance of oxygen, the source was heated to approximately 1800 K; this enabled the Zr–O complex to reach the electron emission area at the source apex, which was several hundred micrometers away from the Zr reservoir. At such a high temperature, the evaporation rate of surface components also increased, making it more difficult for the atoms to diffuse farther. To better understand the mechanisms underlying diffusion and evaporation, the amount of Zr on the surface was estimated using Auger electron spectroscopy. The surface coverage of the Zr–O complex was found to be almost constant up to 600μm without any significant loss. Furthermore, the diffusion of the Zr–O complex was found to be more dominant than evaporation, resulting in coverage saturation. However, when coverage of the Zr–O complex decreased, the observed trends changed drastically, which suggests that the balance of diffusion and evaporation cannot be described by a simple material balance equation. Additionally, the range with a fully covered area of the Zr–O complex became narrower at temperatures higher than 1900 K. These features, however, varied depending on the vacuum level surrounding the sample. Based on these findings, the diffusion and evaporation model of Zr and O on the surface of the Schottky electron source is proposed.
H.Morishita et al., Improvement of type-I method for observing magnetic contrast using scanning electron microscope under tilting-deceleration condition
J. Magn. Mang. Mater.(2021)168733
https://doi.org/10.1016/j.jmmm.2021.168733
ABSTRACT: We developed a method of observing SEM images with a clear magnetic contrast without anisotropy using a scanning electron microscope (SEM). Directional-selective detection of secondary electrons (SEs) is needed to obtain SEM images with a clear magnetic contrast using a type-I method that utilizes changes in the number of detected signals due to a deflection of SEs by the stray magnetic fields of specimens. By combining beam deceleration and specimen tilting (hereinafter “tilting deceleration”), we achieved a directional-selective detection condition for SEs that is preferable for the type-I method. We found that the tilting deceleration method has high sensitivity for fine magnetic domain structures and can visualize submicron-sized magnetic domain structures in a vertically magnetized region of Nd2Fe14B specimens. Furthermore, we synthesized two SEM images with different directional information to reduce the anisotropy of magnetic contrast obtained by the asymmetric detector configuration. As a result, we obtained SEM images with isotropic magnetic contrast, which is similar to that of an SEM image acquired by a spin-SEM equipped with a Mott-type spin-polarization detector.
M.Matsui et al., Mechanism of highly selective etching of SiCN by using NF3/Ar-based plasma
J. Vac. Sci. Technol. A 39, 043008 (2021),
https://doi.org/10.1116/6.0000711
ABSTRACT: As part of the self-aligned processes to fabricate a 3D device, highly selective SiCN etching using NF3/Ar-based gas plasma generated by microwave electron-cyclotron resonance was investigated. The etching rate of SiCN etched by NF3/Ar plasma was higher than that of various other materials, namely, SiO2, Si3N4, poly-Si, TiN, and Al2O3. Extremely highly selective etchings of SiCN with regard to various materials are possible by forming protective layers on nonetched materials by adding gases to the NF3/Ar plasma. The effects of adding gases to the NF3/Ar plasma on various other materials were studied by analysis using optical emission spectroscopy and x-ray photoelectron spectroscopy (XPS). The three key findings of these analyses are summarized as follows. First, highly selective etching of SiCN to poly-Si was achieved by adding oxygen to the NF3/Ar etching plasma. This etching was made possible because poly-Si etching was inhibited by forming a 1.0-nm-thick oxidized layer to protect the poly-Si surface from the etching reaction with fluorine radicals. Second, highly selective etching of SiCN to SiO2 and Si3N4 was achieved by using NF3/Ar-based plasma with added SiCl4. In this etching, silicon-containing deposited layers were formed on the SiO2 and Si3N4 surfaces. The deposited layers protected the surfaces from being etched by reacting with fluorine radicals. Third, highly selective etching over TiN was achieved by using hydrogen-added plasma. The XPS results show that a thin protective layer containing TiNxFy and ammonium fluoride was formed on the TiN surface. The protective layer formed on the TiN surface effectively protects the TiN from being etched by fluorine radicals.
Y.Zhao et al.,Formation Mechanism of Rounded SiGe-Etch Front in Isotropic SiGe Plasma Etching for Gate-All-Around FETs
IEEE J. Electron Devices Soc.9, 1112 (2021),
https://doi.org/10.1109/JEDS.2021.3130916
ABSTRACT: We investigated the formation mechanism of a rounded silicon-germanium (SiGe)-etch front (rounding) in gate-all-around field-effect transistor (GAA-FET) manufacturing. This rounding is created by the isotropic etching of the SiGe layer after anisotropic etching of the SiGe/Si stack, which degrades device characteristics. The etch-time dependence of the rounding amount during isotropic SiGe etching with nitrogen trifluoride plasma indicates that rounding is mainly formed in an initial stage of SiGe etching, namely, etch time less than 15 s. Cross-sectional scanning transmission electron microscopy and energy dispersive x-ray spectroscopy (STEM EDX) measurement indicated that a Ge-containing layer formed on the sidewall of SiGe/Si patterns before isotropic SiGe etching. From these results, we propose a formation model of SiGe rounding below. The Ge composition in the Ge-containing layer has a gradient due to ion-assisted Ge diffusion during anisotropic etching of the SiGe/Si stack. This gradient induces rounding during isotropic SiGe etching because the etch rate of the SiGe layer decreases as the Ge composition decreases. To validate our model, the Ge-containing layer after anisotropic etching was removed by post-etch treatment and the Ge spectra on the sidewall was reduced to the detection limit of STEM EDX. As a result, the rounding amount after isotropic SiGe etching improved from 2.7 to 1.8 nm. This reduction indicates that the formation of the Ge-containing layer during anisotropic etching of the SiGe/Si stack is one of the main causes of rounding after isotropic SiGe etching.
N.Miyoshi et al., Atomic layer etching of SiO2 with self-limiting behavior on the surface modification step using sequential exposure of HF and NH3
J. Vac. Sci. Technol. A 40, 012601 (2022),
https://doi.org/10.1116/6.0001517
ABSTRACT: Thermal atomic layer etching (ALE) for SiO2 films with self-limiting behavior on the surface modification step was developed using sequential exposure to HF and NH3 gases followed by infrared (IR) annealing. X-ray photoelectron spectroscopy analysis showed that an (NH4)2SiF6-based surface-modified layer was formed on the SiO2 surface after gas exposures and that this layer was removed using IR annealing. The etch per cycle (EPC) of the ALE process saturated at 0.9 nm/cycle as the gas exposure times increased. With this self-limiting behavior, SiO2 was etched with high selectivity to poly-Si and Si3N4. The dependence of the EPC on the partial pressures of HF and NH3 was found to be in good agreement with the Langmuir adsorption model. This indicated that the HF and NH3 molecules were in equilibrium between adsorption and desorption during the exposure, which resulted in the self-limiting formation of the modified layer. In addition to the process with an HF gas flow, it was demonstrated that an H2/SF6 plasma can replace the HF gas exposure step to supply the SiO2 surfaces with HF molecules. The EPC saturated at 2.7 nm/cycle, while no measurable thickness change was observed for poly-Si and Si3N4 films.
K. Shinoda et al., Self-limiting reactions of ammonium salt in CHF3/O2 downstream plasma for thermal-cyclic atomic layer etching of silicon nitride
J. Vac. Sci. Technol. A 37, 051002 (2019),
https://doi.org/10.1116/1.5111663
ABSTRACT: Self-limiting reactions of ammonium salt in CHF3/O2 downstream plasma was demonstrated for thermal-cyclic atomic layer etching (ALE) of Si3N4. In-situ X-ray photoelectron spectroscopy (XPS) analysis shows that an (NH4)2SiF6 byproduct of the same thickness forms on Si3N4 in a wide gas composition range. The (NH4)2SiF6 layer prevents etching of Si3N4 during continuous plasma exposure in that wide range. The (NH4)2SiF6 layer was sublimated by heating, which was consistent with the result of thermodynamic calculation. The reactions of the (NH4)2SiF6 layer in CHF3/O2 downstream plasma are used for thermal-cyclic atomic layer etching of Si3N4 with a newly developed 300-mm tool equipped with an in-situ ellipsometer. It was confirmed that the amount etched per cycle saturates with respect to both plasma exposure time and infrared irradiation time.
N.Okai, et al.,Development of Tilt-SEM for In-line 3D Measurement and Inspection of Semiconductor Devices
EIPBN2021,W13 Imaging and Characterization
https://eipbn.org/abstracts/2021/posters/W13.pdf
W.Sun, et al.,Evaluation of deep learning model for 3D profiling of HAR features using high-voltage CD-SEM
SPIE Advanced Lithography, 2021
https://doi.org/10.1117/12.2592052
S.Eto, et al.,Development of Film Thickness Monitor Using Multiple Databases to Improve Robustness Against W2W Device Structure Fluctuation
AEC/APC Symposium Asisa 2021
https://www.semiconportal.com/AECAPC/abstract/MPC-016.pdf
汪海林ほか 機械学習によるメソゲンエポキシ樹脂の液晶相識別
2019年 第80回応用物理学会秋期学術講演会
合同セッションN「インフォマティクス応用」[19p-PB5-3]
https://confit.atlas.jp/guide/event-img/jsap2019a/19p-PB5-3/public/pdf?type=in
Y.Shirasaki, et al.,Charging Induced Electroreflectance for Study of Insulator/Semiconductor Interface
ALC22：Excellent Presentation Award
https://www.jvss.jp/division/mba/alc/alc22/awards.php
半導体製造向け製造/計測システム
高分解能 FEB測長装置「CG7300」
https://www.hitachi-hightech.com/jp/about/news/2019/nr20191211.html
「第9回 ものづくり日本大賞 経済産業大臣賞」受賞
原子サイズレベルの計測精度を実現する寸法検査装置「ＣＧ７３００」の開発
https://www.monodzukuri.meti.go.jp/backnumber/09/index.html
新型高速レビューSEM「CR7300」
https://www.hitachi-hightech.com/jp/about/news/2020/nr20201126.html
電子線広視野検査システム「GS1000」
https://www.hitachi-hightech.com/jp/about/news/2021/nr20211213.html
高加速測長装置「CV6300」
https://www.hitachi-hightech.com/jp/about/news/2019/nr20190702.html
欠陥形状評価SEM 「CT1000」
https://www.hitachi-hightech.com/jp/about/news/2020/nr20201126_2.html
データ駆動型の研究開発を支援する新型FE-SEM「SU8600」「SU8700」
https://www.hitachi-hightech.com/jp/about/news/2021/nr20211209.html
エンハンス版マイクロ波ECRエッチングモジュール
https://www.hitachi-hightech.com/jp/about/news/2018/nr20180322.html
プラズマエッチング装置 稼働率向上のためのAI活用予兆診断システム
https://www.hitachihyoron.com/jp/archive/2020s/2021/01/15/index.html
マテリアルズインフォマティクス
マテリアルズインフォマティクス向け計測ソリューション
https://www.hitachihyoron.com/jp/archive/2010s/2018/06/11a04/index.html
マテリアルズインフォマティクスを適用した材料開発ソリューション
https://www.hitachihyoron.com/jp/archive/2020s/2020/03/03b03/index.html
