Controllable synthesis and characterization of spherical CeO₂ abrasives for chemical mechanical polishing

Abstract

Cerium oxide (CeO₂) is a critical abrasive in chemical mechanical polishing (CMP) due to its chemical-mechanical reactivity and planarization capability. This study developed a controllable hydrothermal synthesis strategy for spherical CeO₂ abrasives and systematically evaluated their CMP performance on silicon wafers. Uniform CeO₂ particles with a fluorite structure were synthesized, as confirmed by scanning electron microscopy, X-ray diffraction, and high-resolution transmission electron microscopy analyses. Mechanistic studies reveal that CeO₂ formation occurred via nitrate-induced oxidation of Ce³⁺. The subsequent precipitation of CeO₂, coupled with acetate decomposition, thermodynamically drove the reaction forward under hydrothermal conditions. By adjusting water volume, the particle size was precisely tuned from 32 to 531 nm while maintaining excellent sphericity and dispersity. CMP tests showed that 343 nm CeO₂ achieved the highest material removal rate (73.7 nm∙min^–1) with low surface roughness (Ra  =  0.31 nm). Optimal polishing with 0.5 wt% CeO₂ achieved a balance between removal efficiency and surface quality, while higher concentrations led to residue defects. Moreover, the hydrothermally synthesized CeO₂ exhibited better CMP performance than commercial abrasives in both short- and long-term polishing, owing to its uniform morphology. Overall, this work demonstrates a simple, effective, and scalable strategy for synthesizing size-controlled CeO₂ abrasives with excellent performance in precision surface processing.

Graphical abstract

Keywords

cerium oxide / controllable synthesis / chemical mechanical polishing

References

[1] Montini T , Melchionna M , Monai M , Fornasiero P . Fundamentals and catalytic applications of CeO₂-based materials. Chemical Reviews, 2016, 116(10): 5987–6041

[2] Zhang W , Zhang P , Wu Y , Li X , Wang X , Wang M , Jin S , Bi W , Zhao Y , Zhou W . et al. Preparation of CeO₂ polishing powder and its performance and mechanism for chemical mechanical polishing of optical glass. ACS Applied Materials & Interfaces, 2025, 17(13): 20394–20410

[3] Li K , Lyu T , He J , Jang B W L . Selective hydrogenation of acetylene over Pd/CeO₂. Frontiers of Chemical Science and Engineering, 2020, 14(6): 929–936

[4] Atzori L , Cutrufello M G , Meloni D , Onida B , Gazzoli D , Ardu A , Monaci R , Sini M F , Rombi E . Characterization and catalytic activity of soft-templated NiO-CeO₂ mixed oxides for CO and CO₂ co-methanation. Frontiers of Chemical Science and Engineering, 2021, 15(2): 251–268

[5] Schmitt R , Nenning A , Kraynis O , Korobko R , Frenkel A I , Lubomirsky I , Haile S M , Rupp J L M . A review of defect structure and chemistry in ceria and its solid solutions. Chemical Society Reviews, 2020, 49(2): 554–592

[6] Krishnan M , Nalaskowski J W , Cook L M . Chemical mechanical planarization: slurry chemistry, materials, and mechanisms. Chemical Reviews, 2010, 110(1): 178–204

[7] Zhang J H , Huang H , Greene A M , Xie R , Seo S C , Montanini P , Tseng W T , Tsai S , Malley M , Fang Q . et al. CMP challenges for advanced technology nodes. MRS Advances, 2017, 2(44): 2361–2372

[8] Han X , Zhang S , Liu R , Wang F , Tan B , Zhao X , Zhao J , Shi Y . The effect of amino acid addition in CeO₂-based slurry on SiO₂/Si₃N₄ CMP: removal rate selectivity, morphology, and mechanism research. Journal of Molecular Liquids, 2024, 412: 125855

[9] Calvache-Muñoz J , Prado F A , Rodríguez-Páez J E . Cerium oxide nanoparticles: synthesis, characterization, and tentative mechanism of particle formation. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017, 529: 146–159

[10] Kim Y H , Kim S K , Kim N , Park J G , Paik U . Crystalline structure of ceria particles controlled by the oxygen partial pressure and STI CMP performances. Ultramicroscopy, 2008, 108(10): 1292–1296

[11] Lee H , Lee D , Jeong H . Mechanical aspects of the chemical mechanical polishing process: a review. International Journal of Precision Engineering and Manufacturing, 2016, 17(4): 525–536

[12] Ma Y , Wang B , Li L , Qiao J , Su Y , Wang D , Wang J . Study on the preparation process of large particle cerium oxide. Journal of Rare Earths, 2010, 28: 136–138

[13] Hu P , Chen Y , Sun R , Chen Y , Yin Y , Wang Z . Synthesis, characterization, and frictional wear behavior of ceria hybrid architectures with {111} exposure planes. Applied Surface Science, 2017, 401: 100–105

[14] Oh M H , Nho J S , Cho S B , Lee J S , Singh R K . Polishing behaviors of ceria abrasives on silicon dioxide and silicon nitride CMP. Powder Technology, 2011, 206(3): 239–245

[15] Kim N Y , Hwang U , Sung J , Park I K , Kim T , Suhr J , Nam J D . Particle size dependence of nanoclustered ceria abrasives on surface activity and chemical mechanical planarization performance. Applied Surface Science, 2024, 663: 160123

[16] Wang Z , Wang T , Zhang L , Lu X . Synthesis of CeO₂ nanoparticles derived by urea condensation for chemical mechanical polishing. Electronic Materials Letters, 2023, 19(6): 580–587

[17] Ren G , Wang L , Wang S . Innovative synthesis of CeO₂ nanoparticles for advanced chemical mechanical polishing. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2025, 705: 135764

[18] Li Y , Wang X , Ding L , Li Y , He R , Li J . Changing the calcination temperature to tune the microstructure and polishing properties of ceria octahedrons. RSC Advances, 2022, 12(26): 16554–16560

[19] Ma J , Xu N , Hu J , Luo Y , Lin Y , Pu Y . Doping strategy on properties and chemical mechanical polishing performance of CeO₂ Abrasives: a DFT assisted experimental study. Applied Surface Science, 2023, 623: 156997

[20] Zhang J , Qu X , Yin J , Wang N . Controllable synthesis of core-shell SiO₂@CeO₂ composite abrasives for chemical mechanical polishing of EMC-Si-Cu multi-heterointerfaces. Materials Chemistry and Physics, 2025, 334: 130509

[21] Jiang S , Liu L , Wang J , Li X , Mei M , Liu S , Xu Z . Ultrasonic vibration assisted chemical mechanical polishing research of PS/CeO₂ core-shell abrasives on SiC ceramics. Applied Surface Science, 2025, 713: 164355

[22] Wang L , Ren G , Xie W , Zhang J , Pan D , Su H , Wang S . Controllable synthesis of core-shell SiO₂@CeO₂ abrasives for chemical mechanical polishing on SiO₂ film. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2024, 682: 132901

[23] Zheng R , Zhu J , Jin L , Cao Z , Zhang C , Han G , Liu Y . Modulation of the chemical mechanical polishing performance of core-shell SnO₂@CeO₂ abrasives via the shape change. Applied Surface Science, 2025, 702: 163378

[24] Panahi-Kalamuei M , Alizadeh S , Mousavi-Kamazani M , Salavati-Niasari M . Synthesis and characterization of CeO₂ nanoparticles via hydrothermal route. Journal of Industrial and Engineering Chemistry, 2015, 21: 1301–1305

[25] Janoš P , Ederer J , Pilařová V , Henych J , Tolasz J , Milde D , Opletal T . Chemical mechanical glass polishing with cerium oxide: effect of selected physico-chemical characteristics on polishing efficiency. Wear, 2016, 362: 114–120

[26] Wang R , Dangerfield R . Seed-mediated synthesis of shape-controlled CeO₂ nanocrystals. RSC Advances, 2014, 4(7): 3615–3620

[27] Oh M H , Singh R K , Gupta S , Cho S B . Polishing behaviors of single crystalline ceria abrasives on silicon dioxide and silicon nitride CMP. Microelectronic Engineering, 2010, 87(12): 2633–2637

[28] Zhou C , Xu X , Dai L , Gong H , Lin S . Chemical-mechanical polishing performance of core-shell structured polystyrene@ceria/nanodiamond ternary abrasives on sapphire wafer. Ceramics International, 2021, 47(22): 31691–31701

[29] Suchak N J , Jethani K , Joshi J B . Absorption of nitrogen oxides in alkaline solutions: selective manufacture of sodium nitrite. Industrial & Engineering Chemistry Research, 1990, 29(7): 1492–1502

[30] Kameoka Y , Pigford R L . Absorption of nitrogen dioxide into water, sulfuric acid, sodium hydroxide, and alkaline sodium sulfite aqueous solutions. Industrial & Engineering Chemistry Fundamentals, 1977, 16(1): 163–169

[31] Lim D S , Ahn J W , Park H S , Shin J H . The effect of CeO₂ abrasive size on dishing and step height reduction of silicon oxide film in STI-CMP. Surface and Coatings Technology, 2005, 200(5): 1751–1754

[32] Li M , Wang M , Liu Z , Hu Y , Wu J . Cerium dioxide with large particle size prepared by continuous precipitation. Journal of Rare Earths, 2009, 27(6): 991–996

[33] Liang X , Xiao J , Chen B , Li Y . Catalytically stable and active CeO₂ mesoporous spheres. Inorganic Chemistry, 2010, 49(18): 8188–8190

[34] Ma J , Xu N , Cheng J , Pu Y . A review on the development of ceria for chemical mechanical polishing. Powder Technology, 2024, 444: 119989

[35] Xie L , Cheng J , Wang T , Lu X . Mechanical wear behavior between CeO₂(100), CeO₂(110), CeO₂(111), and silicon studied through atomic force microscopy. Tribology International, 2021, 153: 106616

[36] Luo J , Dornfeld D A . Material removal mechanism in chemical mechanical polishing: theory and modeling. IEEE Transactions on Semiconductor Manufacturing, 2001, 14(2): 112–133

[37] Lin Y , Wu Z , Wen J , Poeppelmeier K R , Marks L D . Imaging the atomic surface structures of CeO₂ nanoparticles. Nano Letters, 2014, 14(1): 191–196

[38] Hao X , Yoko A , Chen C , Inoue K , Saito M , Seong G , Takami S , Adschiri T , Ikuhara Y . Atomic-scale valence state distribution inside ultrafine CeO₂ nanocubes and its size dependence. Small, 2018, 14(42): 1802915

[39] Deshpande S , Patil S , Kuchibhatla S V , Seal S . Size dependency variation in lattice parameter and valency states in nanocrystalline cerium oxide. Applied Physics Letters, 2005, 87(13): 133113

[40] Kwak D , Oh S , Kim J , Yun J , Kim T . Study on the effect of ceria concentration on the silicon oxide removal rate in chemical mechanical planarization. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2021, 610: 125670

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