针对单晶SiC化学机械抛光使用的抛光液，研究了产生芬顿反应Fe、FeO、Fe2O3、Fe3O4等4种铁系固相催化剂的效果。结果发现当Fe3O4作为催化剂时，SiC表面能够产生明显的化学反应，生成较软易去除的SiO2氧化层，化学机械抛光时材料去除率最高达到17.2 mg/h、表面粗糙度最低达到Ra2.5 nm。相比Fe、FeO、Fe2O3等固相催化剂，Fe3O4更适宜用作SiC的化学机械抛光。抛光液中Fe2+离子浓度和稳定性是决定芬顿反应速率和稳定性的重要因素，固相催化剂电离自由Fe2+能力的差异直接影响了化学抛光液中的Fe2+浓度，固相催化剂电离Fe2+的能力越强，抛光液中Fe2+浓度就越高，芬顿反应速率越快，与SiC进行化学反应速度越快，材料去除率越高，抛光质量越好。
徐少平
,
路家斌
,
阎秋生
,
宋涛
,
潘继生
. 单晶SiC化学机械抛光液的固相催化剂研究[J]. 机械工程学报, 2017
, 53(21)
: 167
-173
.
DOI: 10.3901/JME.2017.21.167
Aiming at the CMP solution of single crystal SiC, the catalytic efficiency of Fe-based solid catalysts such as Fe, FeO, Fe2O3 and Fe3O4 are studied. When Fe3O4 is used as the catalyst of Fenton reaction, an obviously chemical reaction happens on the surface of SiC and a relatively soft SiO2 layer which is easier to be removed is generated, and the highest material removal rate which is 17.2 mg/h and the minimum surface roughness which is Ra2.5 nm are obtained after chemical mechanical polishing. Fe3O4 is more appropriate for CMP of SiC compared with other solid catalysts such as Fe, FeO and Fe2O3. The concentration and stability of Fe2+ in chemical polishing solution are crucial factors deciding the rate and stability of Fenton reaction, and the concentration of Fe2+ is directly affected by the ability of ionizing free Fe2+ of solid catalyst. The stronger the ability of ionizing free Fe2+ of solid catalyst is, the higher the concentration of Fe2+ in polishing solution will be, and then the faster the rate of Fenton reaction will be. In this case, a higher material removal rate and a better polishing quality of SiC will be obtained in CMP.
[1] ZOLPER J C. Emerging silicon carbide power electronics components[C]//Applied Power Electronics Conference and Exposition, 2005. Twentieth Annual IEEE, 2005, 1:11-17.
[2] KATO T, WADA K, HOZOMI E, et al. High throughput SiC wafer polishing wish good surface morphology[J]. Materials Science Forum, 2007, 556:753-756.
[3] 肖强,李言,李淑娟. SiC单晶片CMP超精密加工技术现状与趋势[J]. 宇航材料工艺, 2010, 40(1):9-13. XIAO Qiang, LI Yan, LI Shujuan. The present situation and the trend of CMP ultra-precision machining technology for single SiC wafer[J]. Aerospace Materials & Technology, 2010, 40(1):9-13.
[4] ZHOU L, AUDURIER V, PIROUZ P, et al. Chemomechanical polishing of silicon carbide[J]. Journal of the Electrochemical Society, 1997, 144(6):161-163.
[5] AIDA H, DOI T, TAKEDA H, et al. Ultraprecision CMP for sapphire, GaN, and SiC for advanced optoelectronics materials[J]. Current Applied Physics, 2012, 12(9):41-46.
[6] 彭进,夏琳,邹文俊. 化学机械抛光液的发展现状与研究方向[J]. 表面技术, 2012, 41(4):95-98. PENG Jin, XIA Lin, ZOU Wenjun. The present development situation and the research direction of chemical mechanical polishing solution[J]. Surface Technology, 2012, 41(4):95-98
[7] KUBOTA A, YAGI K, MURATA J, et al. A Study on a surface preparation method for single-crystal SiC using an Fe catalyst[J]. Journal of Electronic Materials, 2009, 38(1):159-163.
[8] SHI X, PAN G, ZHOU Y, et al. Characterization of colloidal silica abrasives with different sizes and their chemical-mechanical polishing performance on 4H-SiC (0001)[J]. Applied Surface Science, 2014, 307(10):414-427.
[9] KUBOTA A, YOSHIMURA M, FUKUYAMA S, et al. Planarization of C-face 4H-SiC substrate using Fe particles and hydrogen peroxide solution[J]. Precision Engineering, 2012, 36(1):137-140.
[10] ZHOU Y, PAN G, SHI X, et al. Chemical mechanical planarization (CMP) of on-axis Si-face SiC wafer using catalyst nanoparticles in slurry[J]. Surface and Coatings Technology, 2014, 251(8):48-55.
[11] WANG L, YAN Q S, LU J B, et al. Comparison of Fe catalyst species in chemical mechanical polishing based on Fenton reaction for SiC wafer[J]. Advanced Materials Research, 2014, 1027:171-176.
[12] GRŽETA B, RISTIĆ M, NOWIK I, et al. Formation of nanocrystalline magnetite by thermal decomposition of iron choline citrate[J]. Journal of Alloys and Compounds, 2002, 334(1):304-312.
[13] 胡宗球,叶效昭,施少敏,等. 配合物[M(AAABA)2(py)2(H2O)2, M=Zn、Mn]的合成、晶体结构、荧光性质和理论研究[J]. 无机化学学报, 2009, 25(8):1389-1395. HU Zongqiu, YE Xiaozhao, SHI Shaomin, et al. The synthesis, crystal structure, fluorescence properties and theoretical research of Complexes[M(AAABA)2(py)2(H2O)2, M=Zn、Mn] [J]. Chinese Journal of Inorganic Chemistry, 2009, 25(8):1389-1395.
[14] 李建英,李盛涛,庄严. SrTiO3双功能陶瓷的施主掺杂研究[J]. 材料研究学报, 2009, 14(2):193-197. LI Jianying, LI Shengtao, ZHUANG Yan. Study on donor doping of SrTiO3 double functional ceramics[J]. Chinese Journal of Materials Research, 2009, 14(2):193-197.
[15] CAO M, LIU T, GAO S, et al. Single-crystal dendritic micrso-pines of magnetic α-Fe2O3:Large-scale synthesis, formation mechanism, and properties[J]. Angewandte Chemie International Edition, 2005, 44(27):4197-4201.
[16] 张克从. 近代晶体学[M]. 北京:科学出版社, 2011. ZHANG Kecong. Modern crystallography[M]. Beijing:Science Press, 2011.
