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

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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Chemical Mechanical Polishing of Gallium Nitride with Colloidal Silica

Journal of The Electrochemical Society ◽

10.1149/2.024112jes ◽

2011 ◽

Vol 158 (12) ◽

pp. H1206 ◽

Cited By ~ 43

Author(s):

Hideo Aida ◽

Hidetoshi Takeda ◽

Koji Koyama ◽

Haruji Katakura ◽

Kazuhiko Sunakawa ◽

...

Keyword(s):

Gallium Nitride ◽

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Mechanical Polishing

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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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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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Preparation of Mg-doped colloidal silica abrasive and its chemical mechanical polishing performances on silicon wafer

2016 China Semiconductor Technology International Conference (CSTIC) ◽

10.1109/cstic.2016.7464032 ◽

2016 ◽

Author(s):

Pan Ma ◽

Hong Lei

Keyword(s):

Silicon Wafer ◽

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Mechanical Polishing ◽

Mg Doped

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Study on effect of the surface variation of colloidal silica abrasive during chemical mechanical polishing of sapphire

Japanese Journal of Applied Physics ◽

10.7567/jjap.56.07kb01 ◽

2017 ◽

Vol 56 (7S2) ◽

pp. 07KB01 ◽

Cited By ~ 8

Author(s):

Natthaphon Bun-Athuek ◽

Yutaka Yoshimoto ◽

Koya Sakai ◽

Panart Khajornrungruang ◽

Keisuke Suzuki

Keyword(s):

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Mechanical Polishing ◽

Surface Variation

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Chemical Mechanical Polishing of Ge Using Colloidal Silica Particles and H2O2

Electrochemical and Solid-State Letters ◽

10.1149/1.3575166 ◽

2011 ◽

Vol 14 (7) ◽

pp. H254 ◽

Cited By ~ 20

Author(s):

Shivaji Peddeti ◽

Patrick Ong ◽

L. H. A. Leunissen ◽

S. V. Babu

Keyword(s):

Chemical Mechanical Polishing ◽

Colloidal Silica ◽

Silica Particles ◽

Mechanical Polishing

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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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