制備、表征及其化學(xué)機(jī)械拋光性能
(1. 常州大學(xué) 材料科學(xué)與工程學(xué)院，常州 213164；2. 蘇州科技學(xué)院 化學(xué)與生物工程學(xué)院，蘇州 215011)
摘 要: 以無(wú)皂乳液聚合法制備的不同粒徑聚苯乙烯(Ploystrene, PS)微球?yàn)閮?nèi)核，以硝酸鈰和六亞甲基四胺為原料，采用液相工藝制備具有核殼結(jié)構(gòu)的PS-CeO2復(fù)合微球。利用X射線衍射儀(XRD)、透射電子顯微鏡(TEM)、場(chǎng)發(fā)射掃描電鏡(FESEM)、傅里葉轉(zhuǎn)換紅外光譜儀(FT-IR)和熱重分析儀(TGA)等對(duì)樣品的成分、物相結(jié)構(gòu)、形貌、粒徑以及團(tuán)聚情況進(jìn)行表征。將所制備的PS-CeO2復(fù)合微球作為磨料用于二氧化硅介質(zhì)層的化學(xué)機(jī)械拋光，用原子力顯微鏡(AFM)觀察拋光表面的微觀形貌，測(cè)量表面粗糙度。結(jié)果表明：所制備的3種PS微球呈單分散規(guī)則球形，粒徑分別約為120、170和240 nm；3種PS-CeO2復(fù)合微球具有核殼結(jié)構(gòu)，粒徑分別約為140、190和260 nm，CeO2殼厚約為10 nm。隨著PS-CeO2復(fù)合磨料粒徑的減小，拋光表面粗糙度隨之降低，經(jīng)樣品F1拋光后表面在10 μm×10 μm面積范圍內(nèi)粗糙度的平均值(Ra)及其均方根(Rms)分別為0.372和0.470 nm。
關(guān)鍵字: PS-CeO2復(fù)合磨料；核殼結(jié)構(gòu)；化學(xué)機(jī)械拋光
core-shell PS-CeO2 composite abrasives with different particle sizes
（1. School of Materials Science and Engineering, Changzhou University, Changzhou 213164, China;
2. School of Chemistry and Biological Engineering,
Suzhou University of Science and Technology, Suzhou 215011, China）
Abstract:Polystyrene (PS) microspheres were prepared by soap-free emulsion polymerization method. Core-shell structured PS-CeO2 composite microspheres were synthesized by liquid phase process using cerium nitrate and hexamethylene tetramine as raw materials. The composition, phase structure, morphology, grain size and agglomeration of the as-prepared composite microspheres were characterized by XRD, TEM, FESEM, FT-IR and TGA. The as-prepared composite microspheres were collocated into polishing abrasives for chemical mechanical polishing (CMP) of silicon dioxide dielectric layer. The morphologies of the dielectric layer after polishing by the composite abrasives were investigated by AFM. The results indicate that the three kinds of PS microspheres are monodispersive and uniform, and the particle size of PS is about 120, 170 and 240 nm, respectively. The particle size of the three kinds of the as-prepared PS-CeO2 composite microspheres is about 140, 190 and 260 nm, respectively, and the thickness of CeO2 shell is about 10 nm. After CMP, the surface roughness of SiO2 dielectric layer decreases with the decrease of the particle size of the composite microspheres. The average roughness Ra and root mean square of roughness Rms of dielectric layer polished by PS-CeO2 composite abrasives in the area of 10 μm ×10 μm are 0.372 and 0.470 nm, respectively.
Key words: PS-CeO2 composite abrasives; core-shell structure; chemical mechanical polishing (CMP)
