Chemical Mechanical Polishing of Gallium Nitride with Colloidal Silica

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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Study on Chemical Mechanical Polishing Technology of Copper

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.373-374.820 ◽

2008 ◽

Vol 373-374 ◽

pp. 820-823

Author(s):

Sheng Li Wang ◽

Y.J. Yuan ◽

Yu Ling Liu ◽

X.H. Niu

Keyword(s):

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Removal Rate ◽

Mechanical Polishing ◽

Alkali Concentration ◽

Copper Films ◽

Optimum Conditions ◽

Slurry Flow Rate ◽

Polishing Pressure ◽

Oxidizer Concentration

Chemical mechanical polishing (CMP) of copper films in alkaline slurries was investigated. In the copper CMP, the slurry was made by adding colloidal silica abrasive to de-ionized water.The organic alkali was added to adjust the pH, H2O2 was used as an oxidizer.The effects of varying polishing temperature, polishing pressure, slurry flow rate, organic alkali concentration and oxidizer concentration on removal rate were investigated in order to determine the optimum conditions for those parameters. It is shown the chemical composition of the slurry was 2%~3% oxidizer concentration, 3% organic alkali concentration and proper amount surfactant is reasonable. The solid concentration of the polishing slurry was fixed at 20% by weight. The removal rate of copper could reach 700nm/min and the surface roughness after CMP was 0.49nm.

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Preparation of cobalt‐doped colloidal silica abrasives and their chemical mechanical polishing performances on sapphire

Micro & Nano Letters ◽

10.1049/mnl.2015.0292 ◽

2015 ◽

Vol 10 (11) ◽

pp. 657-661 ◽

Cited By ~ 7

Author(s):

Pan Ma ◽

Hong Lei ◽

Ruling Chen

Keyword(s):

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Mechanical Polishing

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Chemical mechanical polishing mechanisms for gallium nitride: Quantum chemical molecular dynamics simulations

Proceedings of International Conference on Planarization/CMP Technology 2014 ◽

10.1109/icpt.2014.7017241 ◽

2014 ◽

Author(s):

Kentaro Kawaguchi ◽

Takehiro Aizawa ◽

Yuji Higuchi ◽

Nobuki Ozawa ◽

Momoji Kubo

Keyword(s):

Molecular Dynamics ◽

Gallium Nitride ◽

Molecular Dynamics Simulations ◽

Chemical Mechanical Polishing ◽

Quantum Chemical ◽

Mechanical Polishing ◽

Dynamics Simulations ◽

Quantum Chemical Molecular Dynamics

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Chemical-Mechanical Polishing of Wafers with Copper Film by Nano-Scale Abrasives

Materials Science Forum ◽

10.4028/www.scientific.net/msf.594.181 ◽

2008 ◽

Vol 594 ◽

pp. 181-186

Author(s):

Jhy Cherng Tsai ◽

Jin Fong Kao

Keyword(s):

Citric Acid ◽

Size Effect ◽

Surface Quality ◽

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Removal Rate ◽

Copper Film ◽

Mechanical Polishing ◽

Al2o3 Powder ◽

Abrasive Size

In this paper, experiments are designed and conducted to investigate the effects of abrasive size for Chemical-Mechanical Polishing (CMP) of copper film under different additives in HNO3-based polishing slurries. Alumina modified colloidal silica 100S (φ26nm), 200S (φ40nm) and Al2O3 (φ90nm), are used as polishing abrasives in this study. Experiments showed the following results. (1) With citric acid as an additive to slurry, the removal rate (RR) of the CMP process increases with abrasive size. Surface quality, however, becomes worse at the same time. (2) With benzotriazole (BTA) as an additive, RR of the slurry with Al2O3 powder is slightly higher but it does not increase with the abrasive size in general. Surface quality tends to be worse at the same time though it is not as strong as that in the slurry with citric acid as the additive. (3) The size effect of abrasive on RR with citric acid as additive is stronger than that with BTA.

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Effect of abrasive material properties on polishing rate selectivity of nitrogen-doped Ge2Sb2Te5to SiO2film in chemical mechanical polishing

Journal of Materials Research ◽

10.1557/jmr.2008.0397 ◽

2008 ◽

Vol 23 (12) ◽

pp. 3323-3329 ◽

Cited By ~ 9

Author(s):

Jin-Hyung Park ◽

Hao Cui ◽

Sok-Ho Yi ◽

Jea-Gun Park ◽

Ungyu Paik

Keyword(s):

Crystal Structure ◽

Material Properties ◽

Chemical Mechanical Polishing ◽

Fumed Silica ◽

Colloidal Silica ◽

Mechanical Polishing ◽

Abrasive Material ◽

Nitrogen Doped ◽

The Difference ◽

Abrasive Hardness

We investigated the polishing rate and selectivity of nitrogen-doped Ge2Sb2Te5(NGST) to SiO2film for different abrasive materials (colloidal silica, fumed silica, and ceria abrasives). They both were strongly dependant on abrasive material properties. The polishing rate of nitrogen-doped NGST decreased in the order ceria, fumed silica, and colloidal silica abrasives, which was determined by abrasive material properties, such as abrasive hardness, crystal structure, and primary and secondary abrasive sizes. In addition, the polishing rate slope of NGST film was not significantly different for different abrasive materials, indicating that the polishing of NGST film is mechanical dominant polishing. In contrast, the polishing rate slope of SiO2film decreased in the order ceria, fumed silica, and colloidal silica abrasives, indicating that the polishing of SiO2film is chemical dominant polishing. Furthermore, the difference in polishing rate slopes between NGST and SiO2film gave a polishing rate selectivity of NGST to SiO2film higher than 100:1 with colloidal silica abrasive.

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