Study on the Mechanism of Solid-Phase Oxidant Action in Tribochemical Mechanical Polishing of SiC Single Crystal Substrate

Na2CO3—1.5 H2O2, KClO3, KMnO4, KIO3, and NaOH were selected for dry polishing tests with a 6H-SiC single crystal substrate on a polyurethane polishing pad. The research results showed that all the solid-phase oxidants, except NaOH, could decompose to produce oxygen under the frictional action. After polishing with the five solid-phase oxidants, oxygen was found on the surface of SiC, indicating that all five solid-phase oxidants can have complex tribochemical reactions with SiC. Their reaction products are mainly SiO2 and (SiO2)x. Under the action of friction, due to the high flash point temperature of the polishing interface, the oxygen generated by the decomposition of the solid-phase oxidant could oxidize the surface of SiC and generate a SiO2 oxide layer on the surface of SiC. On the other hand, SiC reacted with H2O and generated a SiO2 oxide layer on the surface of SiC. After polishing with NaOH, the SiO2 oxide layer and soluble Na2SiO3 could be generated on the SiC surface; therefore, the surface material removal rate (MRR) was the highest, and the surface roughness was the largest, after polishing. The lowest MRR was achieved after the dry polishing of SiC with KClO3.

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Homoepitaxial Alignment of SrTiO3 Thin Films Prepared by Metallo-Organic Decomposition.

MRS Proceedings ◽

10.1557/proc-249-201 ◽

1991 ◽

Vol 249 ◽

Cited By ~ 3

Author(s):

Gabriel Braunstein ◽

Gustavo R. Paz-Pujalt

Keyword(s):

Thin Films ◽

Single Crystal ◽

Solid Phase ◽

Single Crystal Substrate ◽

Layer By Layer ◽

Extrinsic Factors ◽

Ion Channeling ◽

Random Nucleation ◽

Crystal Substrate ◽

Organic Decomposition

ABSTRACTWe demonstrate the homoepitaxial growth of SrTiO3 prepared by the method of metallo-organic decomposition (MOD). Thin films of SrTiO3 are prepared by spin-coating and thermal decomposition of a solution of metallo-organic compounds, on single crystal, <100> oriented, SrTiO3 substrates and subsequently heat treated at temperatures ranging from 650°C to 1100°C for 30 minutes. Heat treatment at 1100°C results in the formation of single-crystal SrTiO3, perfectly aligned with respect to the underlying substrate.Ion-channeling analysis shows that the transformation to singlecrystal material proceeds epitaxially from the coating-substrate interface towards the surface of the sample. Transmission electron microscopy (TEM) studies of partially regrown samples reveal two distinct phases: an epitaxially aligned single-crystal phase, adjacent to the substrate, and a polycrystalline phase on top. On the basis of these observations, it is proposed that the crystallization of the MOD films involves the competition between two processes: layer-by-layer solid phase epitaxy and random nucleation and growth of crystallites. Layerby- layer epitaxy is the predominant crystallization mechanism unless it is inhibited by extrinsic factors like the contamination of the interface between the MOD film and the single-crystal substrate.

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Combination of Plasma Electrolytic Processing and Mechanical Polishing for Single-Crystal 4H-SiC

Micromachines ◽

10.3390/mi12060606 ◽

2021 ◽

Vol 12 (6) ◽

pp. 606

Author(s):

Gaoling Ma ◽

Shujuan Li ◽

Xu Liu ◽

Xincheng Yin ◽

Zhen Jia ◽

...

Keyword(s):

Single Crystal ◽

Oxide Layer ◽

Photoelectron Spectroscopy ◽

Material Removal ◽

Smooth Surface ◽

Removal Rate ◽

Mechanical Polishing ◽

Silicon Oxycarbide ◽

X Ray ◽

Plasma Electrolytic

Single-crystal 4H-SiC is a typical third-generation semiconductor power-device material because of its excellent electronic and thermal properties. A novel polishing technique that combines plasma electrolytic processing and mechanical polishing (PEP-MP) was proposed in order to polish single-crystal 4H-SiC surfaces effectively. In the PEP-MP process, the single-crystal 4H-SiC surface is modified into a soft oxide layer, which is mainly made of SiO2 and a small amount of silicon oxycarbide by plasma electrolytic processing. Then, the modified oxide layer is easily removed by soft abrasives such as CeO2, whose hardness is much lower than that of single-crystal 4H-SiC. Finally a scratch-free and damage-free surface can be obtained. The hardness of the single-crystal 4H-SiC surface is greatly decreased from 2891.03 to 72.61 HV after plasma electrolytic processing. By scanning electron microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) observation, the plasma electrolytic processing behaviors of single-crystal 4H-SiC are investigated. The scanning white light interferometer (SWLI) images of 4H-SiC surface processed by PEP-MP for 30 s shows that an ultra-smooth surface is obtained and the surface roughness decreased from Sz 607 nm, Ra 64.5 nm to Sz 60.1 nm, Ra 8.1 nm and the material removal rate (MRR) of PEP-MP is about 21.8 μm/h.

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An Experimental Study of the Polishing Process for MgO Single Crystal Substrate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.329.225 ◽

2007 ◽

Vol 329 ◽

pp. 225-230 ◽

Cited By ~ 4

Author(s):

Ke Wang ◽

Ren Ke Kang ◽

Zhu Ji Jin ◽

Ning Hui Wang

Keyword(s):

Surface Roughness ◽

Single Crystal ◽

Removal Rate ◽

Structural Characteristics ◽

Chemical Properties ◽

Single Crystal Substrate ◽

Polishing Process ◽

Crystal Substrate ◽

Substrate Surfaces ◽

Polishing Efficiency

In order to obtain ultra-smooth and damage free substrate surfaces for MgO single-crystal substrate with high polishing efficiency, an experimental investigation based on systemically designed polishing experiments are presented and discussed. Considering the structural characteristics and chemical properties of the MgO single crystal, the experiments use a polishing slurry containing SiO2 abrasives so that the process is performed under a combination of mechanical and chemical actions. The effects of the polishing process parameters, such as polishing pressure, rotational speed of polishing plate, and the flow rate and concentration of the polishing slurry, on the surface roughness and material removal rate (MRR) are analyzed. Finally, a recommendation is made for selecting the appropriate polishing parameters for MgO single crystal substrate, based on which a surface roughness of 0.3nm can be achieved on the MgO substrate in 20min of polishing time.

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Study on Slurry of SiC Crystal Substrate (0001) C Surface in CMP Based on Silica Sol (SiO2 Abrasive)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.983.214 ◽

2014 ◽

Vol 983 ◽

pp. 214-217

Author(s):

Zhu Qing Zhang ◽

Hai Feng Cheng ◽

Jian Xiu Su

Keyword(s):

Surface Roughness ◽

Chemical Mechanical Polishing ◽

Material Removal ◽

Removal Rate ◽

Orthogonal Design ◽

Substrate Material ◽

Silica Sol ◽

Single Crystal Substrate ◽

Test Results ◽

Crystal Substrate

SiC single crystal substrate has been become an indispensable substrate material in the field of semiconductor lighting. But, there is no report on the commercial slurry of chemical mechanical polishing (CMP) SiC substrate. In this paper, according to orthogonal design, the composition selection and optimization of CMP slurry based on silica sol (SiO2 abrasive) had been done in CMP SiC crystal substrate (0001) C surface by tests. The CMP slurry based on silica sol for SiC crystal substrate (0001) C surface had been obtained. According to the CMP test results, the material removal rate (MRR) is about 15nm/min and the surface roughness Ra is about 0.2nm.

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Dynamic studies of silicide-mediated crystallization of amorphous silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131395 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1352-1353

Author(s):

C. Hayzelden ◽

J. L. Batstone

Keyword(s):

Ion Implantation ◽

Solid Phase ◽

Metallic Phase ◽

Single Crystal Substrate ◽

Free Electrons ◽

Melt Temperature ◽

Transmission Electron ◽

Crystal Substrate ◽

High Resolution Tem

Epitaxial reordering of amorphous Si(a-Si) on an underlying single-crystal substrate occurs well below the melt temperature by the process of solid phase epitaxial growth (SPEG). Growth of crystalline Si(c-Si) is known to be enhanced by the presence of small amounts of a metallic phase, presumably due to an interaction of the free electrons of the metal with the covalent Si bonds near the growing interface. Ion implantation of Ni was shown to lower the crystallization temperature of an a-Si thin film by approximately 200°C. Using in situ transmission electron microscopy (TEM), precipitates of NiSi2 formed within the a-Si film during annealing, were observed to migrate, leaving a trail of epitaxial c-Si. High resolution TEM revealed an epitaxial NiSi2/Si(l11) interface which was Type A. We discuss here the enhanced nucleation of c-Si and subsequent silicide-mediated SPEG of Ni-implanted a-Si.Thin films of a-Si, 950 Å thick, were deposited onto Si(100) wafers capped with 1000Å of a-SiO2. Ion implantation produced sharply peaked Ni concentrations of 4×l020 and 2×l021 ions cm−3, in the center of the films.

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