Optimization of the CMP Process with Colloidal Silica Performance for Bulk AlN Single Crystal Substrate
| Autor: | Won Il Park, Hee Ae Lee, Sung Chul Yi, Jae Hwa Park, Seung Min Kang, Joo-Hyung Lee, Hyo Sang Kang |
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| Rok vydání: | 2019 |
| Předmět: |
Materials science
020502 materials Colloidal silica Metals and Alloys Polishing Substrate (chemistry) 02 engineering and technology Surface finish 021001 nanoscience & nanotechnology Surfaces Coatings and Films Electronic Optical and Magnetic Materials Adsorption 0205 materials engineering Chemical engineering Modeling and Simulation Chemical-mechanical planarization Zeta potential Particle size 0210 nano-technology |
| Zdroj: | Korean Journal of Metals and Materials. 57:582-588 |
| ISSN: | 2288-8241 1738-8228 |
| DOI: | 10.3365/kjmm.2019.57.9.582 |
| Popis: | Chemical mechanical polishing (CMP) of bulk AlN was performed with colloidal silica slurry at pH 9 for different times. The result shows that colloidal silica slurry at pH 9, which has the relatively high surface charge of -50.7 mV is most stable, and it was selected as chemically optimum condition in this study. The ultra-smooth surface was shown in CMP 90 min with the roughness average (Ra) value of 0.172 nm. It was demonstrated that the damaged layers including subsurface defects and micro scratches in the whole machining process were successfully removed and atomically flat surface can be shown. With increasing process time, the zeta potential and mean particle size of the colloidal silica decreased and increased by -35.07 mV and 143.4 nm, respectively. While the silica particles agglomerated and densely packed slurry particles were formed by mechanical shearing. These increased the Ra value above 0.5 nm of AlN substrate and generated additional surface damages. In terms of the surface chemistry, the carbon compounds and organic impurities adsorbed on the substrate during mechanical polishing (MP) can be removed and aluminum oxidehydroxide; AlOOH and Al(OH)3 were observed during the CMP. It was determined that the chemically polished AlN substrate was continuously hydrated with generating the AlOOH and Al(OH)3 on the surface. (Received June 4, 2019; Accepted July 15, 2019) |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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