The effect of yielding of dense silica slurry on the uniformity of coated layer

ABSTRACTSilica slurry used as abrasives in wafer polishing process is made by dispersing silica particles in an alkali solution. Since commercially available colloidal or fumed silica particles need some modifications to be directly used as abrasive slurry due to their small sizes, irregular shapes or broad size distribution, we have prepared silica abrasives by particle growth of fumed silica or colloidal silica as seeds by sol-gel method. Silica slurries prepared by this step-wise growth from commercial seeds were tested using one-armed polisher for the comparison with commercial slurries and showed the performance comparable to commercial slurries. Microstructures of polishing slurries were investigated using transmission electron microscopy and ARES rheometer. From the result, stability of the slurry was found to be more important than the primary particle sizes for the polishing performance.

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Effect of Process Parameters on Material Removal Rate in Chemical Mechanical Polishing of 6H-SiC(0001)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.831 ◽

2008 ◽

Vol 600-603 ◽

pp. 831-834 ◽

Cited By ~ 9

Author(s):

Joon Ho An ◽

Gi Sub Lee ◽

Won Jae Lee ◽

Byoung Chul Shin ◽

Jung Doo Seo ◽

...

Keyword(s):

Material Removal Rate ◽

Chemical Mechanical Polishing ◽

Material Removal ◽

Colloidal Silica ◽

Removal Rate ◽

Mechanical Polishing ◽

Diamond Particles ◽

Average Grain Size ◽

Silica Slurry ◽

Sic Wafer

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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Formability of the Layer Additive Ceramic Part

Materials Science Forum ◽

10.4028/www.scientific.net/msf.594.241 ◽

2008 ◽

Vol 594 ◽

pp. 241-248 ◽

Cited By ~ 4

Author(s):

Fwu Hsing Liu ◽

Yunn Shiuan Liao ◽

Hsiu Ping Wang

Keyword(s):

Surface Roughness ◽

Laser Scanning ◽

Selective Laser Sintering ◽

Single Layer ◽

Dimensional Accuracy ◽

Scanning Speed ◽

Laser Sintering ◽

Single Line ◽

Laser Scanning Speed ◽

Silica Slurry

The material in powder state has long been used by selective laser sintering (SLS) for making rapid prototyping (RP) parts. A new approach to fabricate smoother surface roughness RP parts of ceramic material from slurry-sate has been developed in this study. The silica slurry was successfully laser-gelling in a self-developed laser sintering equipment. In order to overcome the insufficient bonding strength between layers, a strategy is proposed to generate ceramic parts from a single line, a single layer, to multi-layers of gelled cramic in this paper. It is found that when the overlap of each single line is 25% and the over-gel between layers is 30%, stronger and more accurate dimensional parts can be obtained under a laser power of 15W, a laser scanning speed of 250 mm/s, and a layer thickness of 0.1 mm. The 55:45 wt. % of the proportion between the silica powder and silica solution results in suitable viscosity of the ceramic slurries without precipitation. Furthermore, the effects of process parameters for the dimensional accuracy and surface roughness of the gelled parts are investigated and appropriate parameters are obtained.

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Effects of Coated Layer on Spot Weldability of Electro-conductive Vibration Damping Steel Sheets. Spot Weldability of Resin Composite Type Vibration Damping Steel Sheets. (4th Report).

QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY ◽

10.2207/qjjws.14.502 ◽

1996 ◽

Vol 14 (3) ◽

pp. 502-509

Author(s):

Makoto Kabasawa ◽

Yasunori Matsuda ◽

Yasusi Fujii

Keyword(s):

Resin Composite ◽

Vibration Damping ◽

Steel Sheets ◽

Composite Type ◽

Coated Layer

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Evaluation and observation of latex distribution in coated paper by means of EPMA. 1. Study for evaluating latex distribution at coated layer surfaces.

JAPAN TAPPI JOURNAL ◽

10.2524/jtappij.39.477 ◽

1985 ◽

Vol 39 (5) ◽

pp. 477-485 ◽

Cited By ~ 1

Author(s):

Tadahira Hamada ◽

Masahiro Kohno

Keyword(s):

Coated Paper ◽

Coated Layer

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Preparation of PVC composite using reinforced Iraqi Bentoniet clay as a filler & study their mechanical and thermal properties

Baghdad Science Journal ◽

10.21123/bsj.9.3.450-458 ◽

2012 ◽

Vol 9 (3) ◽

pp. 450-458

Author(s):

Baghdad Science Journal

Keyword(s):

Particle Size ◽

Thermal Properties ◽

Polyvinyl Chloride ◽

Bentonite Clay ◽

Mechanical And Thermal Properties ◽

Chloride Solutions ◽

Modified Bentonite ◽

Coated Layer

In this study , Iraqi Bentonite clay was used as a filler for polyvinyl chloride polymer. Bentonite clay was prepared as a powder for some certain particle size ,followed by calcinations process at (300,700,900) OC ,then milled and sieved. The selected sizes were D ~75 µm and D ~150. After that polyvinyl Al-Cohool solution prepared and used as a coated layer covered the Bentonite powder before applied as a filler ,followed by drying , milling and sieving for limited recommend sizes. polyvinyl chloride solutions were prepared and adding of modified Bentonite power at certain quantities were followed .Sheet of these variables on the mechanical and thermal properties of the prepared reinforced particular polyvinyl chloride composite Experimentally, it was found that the composite prepared by adding modified Iraqi Bentonite powder , that calcined at 700 oC as a filler have an advantage in heating insulator properties by 30 from that found for PVC as it is ,and the value of stress strength exceed by three times as that for original value.

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