Effects of Silica Slurry Temperature on Chemical Mechanical Polishing for Tetraethyl Orthosilicate Film

2inch 6H-SiC (0001) wafers were sliced from the ingot grown by a conventional physical vapor transport (PVT) method using an abrasive multi-wire saw. While sliced SiC wafers lapped by a slurry with 1~9㎛ diamond particles had a mean height (Ra) value of 40nm, wafers after the final mechanical polishing using the slurry of 0.1㎛ diamond particles exhibited Ra of 4Å. In this study, we focused on investigation into the effect of the slurry type of chemical mechanical polishing (CMP) on the material removal rate of SiC materials and the change in surface roughness by adding abrasives and oxidizer to conventional KOH-based colloidal silica slurry. The nano-sized diamond slurry (average grain size of 25nm) added in KOH-based colloidal silica slurry resulted in a material removal rate (MRR) of 0.07mg/hr and the Ra of 1.811Å. The addition of oxidizer (NaOCl) in the nano-size diamond and KOH based colloidal silica slurry was proven to improve the CMP characteristics for SiC wafer, having a MRR of 0.3mg/hr and Ra of 1.087Å.

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Colloidal Silica based High Selectivity Shallow Trench Isolation (STI) Chemical Mechanical Polishing (CMP) Slurry

MRS Proceedings ◽

10.1557/proc-867-w8.5 ◽

2005 ◽

Vol 867 ◽

Cited By ~ 2

Author(s):

Kyoung-Ho Bu ◽

Brij M. Moudgil

Keyword(s):

Silicon Nitride ◽

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Sodium Dodecyl ◽

Mechanical Polishing ◽

Wafer Surface ◽

Shallow Trench Isolation ◽

Pattern Size ◽

Trench Isolation ◽

Silica Slurry

AbstractAmong various properties of chemical mechanical polishing (CMP) slurry, selectivity plays a key role in global planarization of high density and small pattern size shallow trench isolation (STI) process. Lack of adequate selectivity can lead to defects such as dishing and erosion. To improve the selectivity of STI CMP process, CMP characteristics of silica and silicon nitride wafer were investigated using colloidal silica slurry as a function of slurry pH. Sodium dodecyl sulfate (SDS), an anionic surfactant, was added to increase the selectivity of the slurry. As a result, selectivity increased from 3 to 25. It was concluded that selective passivation layer formed on silicon nitride wafer surface at acidic slurry pH range was responsible for the observed selectivity increase. Adsorption characteristics of SDS on silica and silicon nitride were measured as a function of slurry pH and concentration of SDS. As indicated by zeta potential behavior under acidic pH conditions, SDS adsorption on silicon nitride was significantly higher han silica due to the electrostatic forces. Significantly higher SDS coating on silicone nitride seems to have resulted in lubrication layer leading to increased polishing selectivity.

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A New Poly-Si CMP Process with Small Erosion for Advanced Trench Isolation Process

MRS Proceedings ◽

10.1557/proc-612-d11.3.1 ◽

2000 ◽

Vol 612 ◽

Author(s):

Naoto Miyashita ◽

Shin-ichiro Uekusa ◽

Takeshi Nishioka ◽

Satoko Iwami

Keyword(s):

Experimental Work ◽

Chemical Mechanical Polishing ◽

Process Integration ◽

Mechanical Polishing ◽

Ph Dependency ◽

Erosion Level ◽

Organic Surfactant ◽

New Process ◽

Trench Isolation ◽

Silica Slurry

AbstractChemical-Mechanical Polishing has been revealed as an attractive technique for poly-Si of trench planalization. Major issue of the process integration is pattern erosion after over polishing. A new process with silica slurry containing organic surfactant is reported in this paper. A patterned wafer after conventional CMP process is eroded by over polishing, however, the new process conducts small erosion for wide trenches. The organic surfactant is well known as a inhibitor for the protection of poly-Si from alkaline, and the new slurry shows a large pH dependency of the viscosity. The experimental work has been focused on the viscosity, and the mechanism of the small erosion is discussed. This new process should be useful for recessing poly-Si by CMP, because it keeps the erosion level very low.

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Effects of manganese oxide–mixed abrasive slurry on the tetraethyl orthosilicate oxide chemical mechanical polishing for planarization of interlayer dielectric film in the multilevel interconnection

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.2936225 ◽

2008 ◽

Vol 26 (4) ◽

pp. 996-1001 ◽

Cited By ~ 5

Author(s):

Yong-Jin Seo ◽

Sung-Woo Park ◽

Woo-Sun Lee

Keyword(s):

Manganese Oxide ◽

Chemical Mechanical Polishing ◽

Dielectric Film ◽

Tetraethyl Orthosilicate ◽

Mechanical Polishing ◽

Interlayer Dielectric

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Fumed Silica Slurry Stabilizing Methods for Chemical Mechanical Polishing

Japanese Journal of Applied Physics ◽

10.1143/jjap.42.418 ◽

2003 ◽

Vol 42 (Part 1, No. 2A) ◽

pp. 418-423 ◽

Cited By ~ 9

Author(s):

Shinichi Haba ◽

Keiji Fukuda ◽

Yoshiharu Ohta ◽

Yasushi Koubuchi ◽

Takashi Katouda

Keyword(s):

Chemical Mechanical Polishing ◽

Fumed Silica ◽

Mechanical Polishing ◽

Silica Slurry

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A New Poly-Si CMP Process with Small Erosion for Advanced Trench Isolation Process

MRS Proceedings ◽

10.1557/proc-613-e5.3.1 ◽

2000 ◽

Vol 613 ◽

Cited By ~ 1

Author(s):

Naoto Miyashita ◽

Shin-ichiro Uekusa ◽

Takeshi Nishioka ◽

Satoko Iwami

Keyword(s):

Experimental Work ◽

Chemical Mechanical Polishing ◽

Process Integration ◽

Mechanical Polishing ◽

Ph Dependency ◽

Erosion Level ◽

Organic Surfactant ◽

New Process ◽

Trench Isolation ◽

Silica Slurry

ABSTRACTChemical-Mechanical Polishing has been revealed as an attractive technique for poly-Si of trench planalization. Major issue of the process integration is pattern erosion after over polishing. A new process with silica slurry containing organic surfactant is reported in this paper. A patterned wafer after conventional CMP process is eroded by over polishing, however, the new process conducts small erosion for wide trenches. The organic surfactant is well known as a inhibitor for the protection of poly-Si from alkaline, and the new slurry shows a large pH dependency of the viscosity. The experimental work has been focused on the viscosity, and the mechanism of the small erosion is discussed. This new process should be useful for recessing poly-Si by CMP, because it keeps the erosion level very low.

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Dynamic Contact Characteristics During Chemical Mechanical Polishing (CMP)

MRS Proceedings ◽

10.1557/proc-767-f1.10 ◽

2003 ◽

Vol 767 ◽

Cited By ~ 2

Author(s):

Wonseop Choi ◽

Seung-Mahn Lee ◽

Rajiv K. Singh

Keyword(s):

Friction Force ◽

Chemical Mechanical Polishing ◽

Dynamic Contact ◽

Mechanical Polishing ◽

Force Measurements ◽

Solids Loading ◽

Silica Slurry ◽

Contact Mechanism ◽

Lateral Friction

AbstractIn chemical mechanical polishing (CMP), it is critical to understand dynamic contact at the pad-particles-wafer interface for desired CMP performance. The dynamic contact is dependent on process variables (platen velocity and down pressure) and particle characteristics (size and concentration), which in turn affect friction force. In this study, we have characterized the dynamic contact at the pad-particles-wafer interface as a function of platen velocity and down pressure. In situ lateral friction force measurements were carried out for silica slurry / sapphire wafer system in order to investigate the dynamic contact during polishing. As solids loading increases, the slope in the friction force vs. platen velocity curve changes from a negative to a positive value. Friction force increases with down pressure for different solids loading conditions. Consequently, friction force is determined as a function of down pressure and platen velocity, validating a dynamic contact mechanism during CMP.

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