Chemical mechanical polishing for sapphire wafers using a developed slurry. (February 2021)

• Record Type: Journal Article
• Authors: Zhang, Zhenyu; Liu, Jie; Hu, Wei; Zhang, Lezhen; Xie, Wenxiang; Liao, Longxing
• Is Part Of: Journal of manufacturing processes. Volume 62(2021)
• Page Start: 762
• Page End: 771
• Publication Date: 2021-02
• Subjects: Sapphire -- CMP -- XPS -- IR -- Green; Production management -- Data processing -- Periodicals; Manufacturing processes -- Periodicals; Procestechnologie; Productietechniek; Production -- Gestion -- Informatique -- Périodiques; Fabrication -- Périodiques; Manufacturing processes; Production management -- Data processing; Periodicals; 670.5
• DOI: 10.1016/j.jmapro.2021.01.004
• Languages: English
• ISSNs: 1526-6125

Abstract

Abstract: At present, corrosive ingredients are widely employed in chemical mechanical polishing (CMP) of sapphire, bringing a potential threat to both people and environment. This results in high cost and long processing time on the treatment of CMP slurry of sapphire. It is a challenge to develop a novel green CMP for sapphire to meet the stringent requirements of high performance products. In this study, a novel green CMP is proposed for sapphire, consisting of silica nanoparticles of 50 nm, triethanolamine (TEA), sodium metasilicate nonahydrate, and deionized water. After green CMP, surface roughness Ra, root mean square (rms), and peak-to-valley (PV) are 0.11, 0.139, and 1.65 nm, respectively. Material removal rate is 3.31 μm/h during green CMP. To the best of our knowledge, surface roughness Ra and rms after green CMP developed are the lowest on a sapphire wafer, compared with those reported previously. The CMP mechanism is elucidated by X-ray photoelectron spectroscopy (XPS) and infrared (IR) spectra. Sapphire formed Al(OH)4 − ions in an alkaline environment, which was chelated by TEA, and removed from the surface of sapphire. These findings provide new insights to fabricate high performance devices of sapphire for the use in semiconductor and microelectronic industries.