Study on the Machining Parameters in Polishing Single-Crystal SiC Wafers with SG Films

2013 ◽  
Vol 589-590 ◽  
pp. 457-463 ◽  
Author(s):  
Zhi Du ◽  
Jing Lu ◽  
Cong Fu Fang ◽  
Hui Huang ◽  
Xi Peng Xu
Keyword(s):  
Surface Roughness ◽  
Single Crystal ◽  
Smooth Surface ◽  
Sol Gel ◽  
Machining Parameters ◽  
Processing Quality ◽  
Rotating Speed ◽  
Single Crystal Sic ◽  
Sic Wafer ◽  
Diamond Abrasive

In this paper, diamond abrasive SG films were prepared by means of sol-gel technology for polishing single-crystal SiC wafers. The effects of machining parameters on processing quality including pressure, rotating speed and polishing time were investigated, respectively. The results indicated that the surface roughness decreased with increasing polishing time. While for pressure and rotating speed, there were inflections existing. Polishing SiC wafer under optimized machining parameters, an ultra smooth surface with the roughness of 3.7 nm could be achieved using 40 μm diamond grits.

scholarly journals Investigation on the Material Removal and Surface Generation of a Single Crystal SiC Wafer by Ultrasonic Chemical Mechanical Polishing Combined with Ultrasonic Lapping

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2022 ◽  
Author(s):  
Yong Hu ◽  
Dong Shi ◽  
Ye Hu ◽  
Hongwei Zhao ◽  
Xingdong Sun
Keyword(s):  
Surface Roughness ◽  
Single Crystal ◽  
Material Removal Rate ◽  
Chemical Mechanical Polishing ◽  
Material Removal ◽  
Removal Rate ◽  
Surface Generation ◽  
Ultrasonic Assisted ◽  
Single Crystal Sic ◽  
Sic Wafer

A new method of ultrasonic chemical mechanical polishing (CMP) combined with ultrasonic lapping is introduced to improve the machining performance of carbide silicon (SiC). To fulfill the method, an ultrasonic assisted machining apparatus is designed and manufactured. Comparative experiments with and without ultrasonic assisted vibration are conducted. According to the experimental results, the material removal rate (MRR) and surface generation are investigated. The results show that both ultrasonic lapping and ultrasonic CMP can decrease the two-body abrasion and reduce the peak-to-valley (PV) value of surface roughness, the effect of ultrasonic in lapping can contribute to the higher MRR and better surface quality for the following CMP. The ultrasonic assisted vibration in CMP can promote the chemical reaction, increase the MRR and improve the surface quality. The combined ultrasonic CMP with ultrasonic lapping achieved the highest MRR of 1.057 μm/h and lowest PV value of 0.474 μm. Therefore this sequent ultrasonic assisted processing method can be used to improve the material removal rate and surface roughness for the single crystal SiC wafer.

Development of the Local Polishing Technique for Single-Crystal SiC Wafer

2015 ◽  
Vol 656-657 ◽  
pp. 204-207 ◽  
Author(s):  
Shin Nagae ◽  
Akihisa Kubota ◽  
Mutsumi Touge
Keyword(s):  
Hydrogen Peroxide ◽  
Surface Roughness ◽  
Single Crystal ◽  
Hydrogen Peroxide Solution ◽  
Dramatic Improvement ◽  
Single Crystal Sic ◽  
Method Effects ◽  
Sic Wafer ◽  
Surface Microroughness

We have developed a novel polishing technique by scanning a small magnetic tool in hydrogen peroxide solution for smoothing a 2-inch SiC wafer. Obtained results show that the surface roughness in almost areas on the 2-inch SiC wafer is improved markedly. Our proposed method effects a dramatic improvement in a surface microroughness from 0.699 nm Rms to 0.079 nm Rms.

Ultra-precision grinding of 4H-SiC wafer by PAV/PF composite sol-gel diamond wheel

2021 ◽  
Vol 13 (9) ◽  
pp. 168781402110449
Author(s):  
Kaiping Feng ◽  
Tianchen Zhao ◽  
Binghai Lyu ◽  
Zhaozhong Zhou
Keyword(s):  
Surface Roughness ◽  
Low Temperature ◽  
Polyvinyl Alcohol ◽  
Feed Rate ◽  
Hot Pressing ◽  
Phenolic Resin ◽  
Sol Gel ◽  
Diamond Wheel ◽  
Sic Wafer ◽  
Better Than

To eliminate the deep scratches on the 4H-SiC wafer surface in the grinding process, a PVA/PF composite sol-gel diamond wheel was proposed. Diamond and fillers are sheared and dispersed in the polyvinyl alcohol-phenolic resin composite sol glue, repeatedly frozen at a low temperature of −20°C to gel, then 180°C sintering to obtain the diamond wheel. Study shows that the molecular chain of polyvinyl alcohol-phenolic resin is physically cross-linked to form gel under low-temperature conditions. Tested by mechanical property testing machines, microhardness tester, and SEM. The results show that micromorphology is more uniform, the strength of the sol-gel diamond wheel is higher, the hardness uniformity is better than that of the hot pressing diamond wheel. Grinding experiments of 4H-SiC wafer were carried out with the prepared sol-gel diamond wheel. The influence of grinding speed, feed rate, and grinding depth on the surface roughness was investigated. The results showed that by using the sol-gel diamond wheel, the surface quality of 4H-SiC wafer with an average surface roughness Ra 6.42 nm was obtained under grinding wheel speed 7000 r/min, grinding feed rate 6 µm/min, and grinding depth 15 µm, the surface quality was better than that of using hot pressing diamond wheel.

Mechanochemical Polishing of Single Crystal Diamond with Mixture of Oxidizing Agents

2006 ◽  
Vol 315-316 ◽  
pp. 852-855 ◽  
Author(s):  
Cheng Yong Wang ◽  
C. Chen ◽  
Yue Xian Song
Keyword(s):  
Surface Roughness ◽  
Single Crystal ◽  
Smooth Surface ◽  
Removal Rate ◽  
Polishing Process ◽  
Iron Plate ◽  
Oxidizing Agents ◽  
Single Crystal Diamond ◽  
Lower Temperature ◽  
And Control

In order to achieve the smooth surface of diamond, several kinds of mixture oxidizing agents have been used to polish the single crystal diamond by a designed polishing apparatus. The existing of graphite and amorphous carbon has been found in the surface of diamond after polishing. The mechanochemical actions of oxidizing agents and the polishing iron plate have been proved. The mixture of oxidizing agents can decrease the polishing temperature so that the super-smooth surface of single crystal diamond can be achieved at lower temperature. The method provided is benefit not only to simplify polishing device and control the polishing process, but also to improve the removal rate and surface roughness.

Detection and Analysis of Subsurface Cracks of Single Crystal SiC Wafers Based on Cross-Sectional Microscopy Method

2014 ◽  
Vol 1027 ◽  
pp. 240-245
Author(s):  
Qiu Sheng Yan ◽  
Sen Kai Chen ◽  
Ji Sheng Pan
Keyword(s):  
Sample Preparation ◽  
Single Crystal ◽  
Crack Detection ◽  
Preparation Method ◽  
Subsurface Crack ◽  
Cross Sectional ◽  
Preparation Methods ◽  
Subsurface Cracks ◽  
Single Crystal Sic ◽  
Sic Wafer

For subsurface crack detection of single crystal SiC wafer, this paper proposed a cross-sectional cleavage detection method and compared with traditional cross-sectional sample preparation method. The characteristics and detection results of two cross-sectional sample preparation methods were compared and the subsurface crack characteristics in SiC wafer grinding were researched. The results show that the configurations and depth of subsurface cracks measured by two cross-sectional sample preparation methods were similar. The cross-sectional cleavage sample preparation method is simpler and more rapid in subsurface crack detection. The subsurface crack system of single crystal SiC wafer grinding mainly includes lateral crack and median crack.

scholarly journals Effects of Depth of Cutting on Damage Interferences during Double Scratching on Single Crystal SiC

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 519
Author(s):  
Duan Nian
Keyword(s):  
Single Crystal ◽  
Material Removal ◽  
Single Crystal Silicon ◽  
Crystal Silicon ◽  
Particle Hydrodynamics ◽  
Single Crystal Sic ◽  
Smoothed Particle ◽  
Planarization Process ◽  
Material Removal Mode ◽  
Sic Wafer

In this work, the damage interference during scratching of single crystal silicon carbide (SiC) by two cone-shaped diamond grits was experimentally investigated and numerically analyzed by coupling the finite element method (FEM) and smoothed particle hydrodynamics (SPH), to reveal the interference mechanisms during the micron-scale removal of SiC at variable Z-axis spacing along the depth of cutting (DOC) direction. The simulation results were well verified by the scratching experiments. The damage interference mechanism of SiC during double scratching at micron-scale was found to be closely related to the material removal modes, and can be basically divided into three stages at different DOCs: combined interference of plastic and brittle removal in the case of less than 5 µm, interference of cracks propagation when DOC was increased to 5 µm, and weakened interference stage during the fracture of SiC in the case of greater than 5 µm. Hence, DOC was found to play a determinant role in the damage interference of scratched SiC by influencing the material removal mode. When SiC was removed in a combined brittle-plastic mode, the damage interference occurred mainly along the DOC direction; when SiC was removed in a brittle manner, the interference was mainly along the width of cutting; and more importantly, once the fragment of SiC was initiated, the interference was weakened and the effect on the actual material removal depth also reduces. Results obtained in this work are believed to have essential implications for the optimization of SiC wafer planarization process that is becoming increasingly important for the fabrication of modern electronic devices.

Processing Single Crystal SiC with Semi-Consolidated Polishing Film

2016 ◽  
Vol 874 ◽  
pp. 401-406
Author(s):  
Jing Lu ◽  
Guang Qiu Hu ◽  
Hua Guo ◽  
Xi Peng Xu
Keyword(s):  
Single Crystal ◽  
Sol Gel ◽  
Wide Band ◽  
Wafer Surface ◽  
Work Piece ◽  
Wide Band Gap ◽  
Flexible Tool ◽  
Diamond Grit ◽  
Single Crystal Sic ◽  
Process Material

Single crystal SiC has been considered as a leading wide band gap semiconductor for its excellent properties even in severe environments. While the outstanding chemical and mechanical inertness also makes it a difficult to process material. In this work, a flexible machining method was proposed to polish 6H-SiC wafers with semi-consolidated diamond tools prepared by sol-gel technology. To confirm the machining mechanism of this newly developed method, free abrasive polishing slurry and fixed abrasive lapping film were also used for comparative experiments. The results indicated that high quality wafer surface with roughness of Ra 0.962 nm was achieved by using semi-consolidated polishing film with diamond grit size of 1 μm. And compared to the other two machining methods, the abrasive in this flexible tool would take a retraction when polishing, leading to a smoother and scratch-free surface of the work piece.

Preliminary Study on Highly Efficient Polishing of 4H-SiC by Utilization of Anodic Oxidation

2014 ◽  
Vol 1017 ◽  
pp. 509-514 ◽  
Author(s):  
Kazuya Yamamura ◽  
Kenji Hosoya ◽  
Yusuke Imanishi ◽  
Hui Deng ◽  
Katsuyoshi Endo
Keyword(s):  
Surface Roughness ◽  
Phosphoric Acid ◽  
Single Crystal ◽  
Anodic Oxidation ◽  
Chemical Mechanical Polishing ◽  
Oxidation Rate ◽  
Removal Rate ◽  
Experimental Results ◽  
Single Crystal Sic ◽  
Preliminary Study

Preliminary study on anodic-oxidation-assisted polishing (AOAP) of 4H-SiC (0001) using ceria polishing film was demonstrated. In the case of using deionized (DI) water as an electrolyte, rms roughness of 0.16 nm was obtained, which is almost the same as roughness of the surface finished by conventional chemical mechanical polishing (CMP). However, the polishing rate was very low and was 23 nm/h. In contrast, the polishing rate of 0.84 μm/h, which is equal to that of conventional CMP of single-crystal SiC or greater, was obtained when we used 1 wt% of phosphoric acid (H3PO4) as the electrolyte, although the surface roughness increased to rms roughness of 1 nm order. These experimental results indicate that the polishing rate greatly depends on the oxidation rate of anodic oxidation and the balance between the oxidation rate and the removal rate of oxide by abrasive greatly affects the roughness of the processed surface.

Sign in / Sign up

Export Citation Format

Share Document