Study on Nanoparticle Agglomeration During Chemical Mechanical Polishing (CMP) Performance

2021 ◽  
Vol 10 (3) ◽  
pp. 420-430
Author(s):  
Mohammed A. Y. A. Bakier ◽  
Keisuke Suzuki ◽  
Panart Khajornrungruang
Keyword(s):  
Chemical Mechanical Polishing ◽  
Shear Force ◽  
Removal Rate ◽  
Thermal Characteristics ◽  
Mechanical Polishing ◽  
Reciprocal Relationship ◽  
Surface Finishing ◽  
Slurry Flow ◽  
Nanoparticle Agglomeration ◽  
Materials Used

The materials used in base fluids and nanoparticles are varied. One- and two-step manufacturing processes are used to create stable and highly conductive nanofluids. Both methods for making nanoparticle suspensions suffer from nanoparticle agglomeration, which is a major problem in any technique that uses nanopowders. As a result, the key to substantial surface finishing at planarization treatments and increase in the thermal characteristics of nanofluids is the production and suspension of almost non-agglomerated or monodispersed nanoparticles in liquids. This unfavorable aggregation is a major problem in nanopowder technology. Primary material constituents agglomerate rapidly overcoming the stable situation, and nanoparticle agglomerates set out in liquids, making it difficult to create nanofluids using two-step techniques. This research looks at the link between nanoparticle agglomeration during slurry flow and Material Removal Rate (MRR) during chemical mechanical polishing (CMP). The reciprocal relationship between MRR and the shear force exerted by the slurry flow was qualitatively elucidated by the researchers for the theoretical investigation. However, the present manipulation is focused on quantifying the shear stress exerted by nanoparticles floating in the slurry. As a result, the MRR-aggregation model is established based on the relationship between MRR and shear force. The experiment is being carried out to support this idea. The experimental results of aggregation and shear forces have been conducted by some recent studies. However, the extension to the real CMP is very promising for accomplishing a precise style of the removal mechanism and surface finishing criterion as well.

Feature-Scale Simulations of Particulate Slurry Flows in Chemical Mechanical Polishing by Smoothed Particle Hydrodynamics

2014 ◽  
Vol 16 (5) ◽  
pp. 1389-1418 ◽  
Author(s):  
Dong Wang ◽  
Sihong Shao ◽  
Changhao Yan ◽  
Wei Cai ◽  
Xuan Zeng
Keyword(s):  
Smoothed Particle Hydrodynamics ◽  
Chemical Mechanical Polishing ◽  
Removal Rate ◽  
Mechanical Polishing ◽  
Slurry Flow ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Slurry Flows ◽  
Smoothed Particle ◽  
Feature Scale

AbstractIn this paper, the mechanisms of material removal in chemical mechanical polishing (CMP) processes are investigated in detail by the smoothed particle hydrodynamics (SPH) method. The feature-scale behaviours of slurry flow, rough pad, wafer defects, moving solid boundaries, slurry-abrasive interactions, and abrasive collisions are modelled and simulated. Compared with previous work on CMP simulations, our simulations incorporate more realistic physical aspects of the CMP process, especially the effect of abrasive concentration in the slurry flows. The preliminary results on slurry flow in CMP provide microscopic insights on the experimental data of the relation between the removal rate and abrasive concentration and demonstrate that SPH is a suitable method for the research of CMP processes.

Effect of Shear and Thermal Characteristics on Chemical Mechanical Polishing

2010 ◽  
Vol 126-128 ◽  
pp. 271-275
Author(s):  
Hung Jung Tsai ◽  
Jeng Haur Horng ◽  
Hung Cheng Tsai ◽  
Shun Jung Chiu ◽  
Pay Yau Huang
Keyword(s):  
Chemical Mechanical Polishing ◽  
Shear Force ◽  
Volume Flow Rate ◽  
Thermal Characteristics ◽  
Mechanical Polishing ◽  
Experimental Results ◽  
Theoretical Simulation ◽  
Lubrication Equation ◽  
Chemical Mechanical Polishing Process ◽  
Load Transducer

Chemical mechanical polishing has been widely used to achieve global planarization of wafers. In this paper, an improved designed test rig is used to acquire the signals on chemical mechanical polishing. The shear force and temperature-rise are measured during chemical mechanical polishing process. The polishing temperature is measured by T-type thermocouples screwed behind the polishing interface of the carrier. The shear force is measured by a load transducer mounted on the lever and connected with the polishing head. The parameters including down force, rotation speed, particle size and volume flow rate of slurry are investigated. The experimental results provide a good index to end-point-detection. The theoretical simulation by the average lubrication equation coincides with the experimental results. This study contributes to the understanding of chemical mechanical polishing mechanism.

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

2008 ◽  
Vol 600-603 ◽  
pp. 831-834 ◽  
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.

Optimization of chemical mechanical polishing parameters on surface roughness of steel substrate with aluminum nanoparticles via Taguchi approach

2014 ◽  
Vol 66 (6) ◽  
pp. 685-690 ◽  
Author(s):  
De-Xing Peng
Keyword(s):  
Flow Rate ◽  
Chemical Mechanical Polishing ◽  
Steel Substrate ◽  
Value Added ◽  
Mechanical Polishing ◽  
Slurry Flow ◽  
Average Roughness ◽  
Content Type ◽  
Optimization Parameters ◽  
Slurry Flow Rate

Purpose – The purpose of this paper is to investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Chemical mechanical polishing (CMP) is now widely used in the aerospace industry for global planarization of large, high value-added components. Design/methodology/approach – Optimal parameters are applied in experimental trials performed to investigate the effects of abrasive contents, oxidizer contents, slurry flow rate and polishing time in achieving a mirror-like finish on polished surfaces. Taguchi design experiments are performed to optimize the parameters of CMP performed in steel specimens. Findings – Their optimization parameters were found out; the surface scratch, polishing fog and remaining particles were reduced; and the flatness of the steel substrate was guaranteed. The average roughness (Ra) of the surface was reduced to 6.7 nm under the following process parameters: abrasive content of 2 weight per cent, oxidizer content of 2 weight per cent, slurry flow rate of 100 ml/min and polishing time of 20 min. Originality/value – To meet the final process requirements, the CMP process must provide a good planarity, precise selectivity and a defect-free surface. Surface planarization of components used to fabricate aerospace devices is achieved by CMP process, which enables global planarization by combining chemical and mechanical interactions.

Modeling of Polishing Regimes in Chemical Mechanical Polishing

2005 ◽  
Vol 867 ◽  
Author(s):  
Suresh B. Yeruva ◽  
Chang-Won Park ◽  
Brij M. Moudgil
Keyword(s):  
Chemical Mechanical Polishing ◽  
Material Removal ◽  
Removal Rate ◽  
Mechanical Polishing ◽  
Operating Conditions ◽  
Comprehensive Model ◽  
Mechanical Effects ◽  
Microelectronic Devices ◽  
Asperity Distribution ◽  
Modification Of The Surface

AbstractChemical mechanical polishing (CMP) is widely used for local and global planarization of microelectronic devices. It has been demonstrated experimentally in the literature that the polishing performance is a result of the synergistic effect of both the chemicals and the particles involved in CMP. However, the fundamental mechanisms of material removal and the interactions of the chemical and mechanical effects are not well understood. A comprehensive model for CMP was developed taking into account both the chemical and mechanical effects for monodisperse slurries. The chemical aspect is attributed to the chemical modification of the surface layer due to slurry chemistry, whereas the mechanical aspect is introduced by indentation of particles into the modified layer and the substrate depending on the operating conditions. In this study, the model is extended to include the particle size and pad asperity distribution effects. The refined model not only predicts the overall removal rate but also the surface roughness of the polished wafer, which is an important factor in CMP. The predictions of the model show reasonable agreement with the experimental observations.

A Model for Optimizing Material Removal Rate in Low-Pressure CMP: Effects of Pad Porosity and Abrasive Concentration

2008 ◽  
Author(s):  
Dinc¸er Bozkaya ◽  
Sinan Mu¨ftu¨
Keyword(s):  
Material Removal Rate ◽  
Chemical Mechanical Polishing ◽  
Material Removal ◽  
Removal Rate ◽  
Applied Pressure ◽  
Low Pressure ◽  
Mechanical Polishing ◽  
Low K

The necessity to planarize ultra low-k (ULK) dielectrics [1], and the desire to reduce polishing defects leads to use of lower polishing pressures in chemical mechanical polishing (CMP). However, lowering the applied pressure also decreases the material removal rate (MRR), which causes the polishing time for each wafer to increase. The goal of this work is to investigate effects of pad porosity and abrasive concentration on the MRR.

Investigation on Smoothing Silicon Carbide Wafer With a Combined Method of Mechanical Lapping and Photocatalysis Assisted Chemical Mechanical Polishing

2018 ◽  
Author(s):  
Zewei Yuan ◽  
Kai Cheng ◽  
Yan He ◽  
Meng Zhang
Keyword(s):  
Silicon Carbide ◽  
Chemical Mechanical Polishing ◽  
Material Removal ◽  
Removal Rate ◽  
Mechanical Polishing ◽  
Combined Method ◽  
Polishing Process ◽  
High Quality ◽  
Quality Surface ◽  
High Quality Surface

The high quality surface can exhibit the irreplaceable application of single crystal silicon carbide in the fields of optoelectronic devices, integrated circuits and semiconductor. However, high hardness and remarkable chemical inertness lead to great difficulty to the smoothing process of silicon carbide. Therefore, the research presented in this paper attempts to smooth silicon carbide wafer with photocatalysis assisted chemical mechanical polishing (PCMP) by using of the powerful oxidability of UV photo-excited hydroxyl radical on surface of nano-TiO2 particles. Mechanical lapping was using for rough polishing, and a material removal model was proposed for mechanical lapping to optimize the polishing process. Several photocatalysis assisted chemical mechanical polishing slurries were compared to achieve fine surface. The theoretical analysis and experimental results indicate that the material removal rate of lapping process decreases in index form with the decreasing of abrasive size, which corresponds with the model developed. After processed with mechanical lapping for 1.5 hours and subsequent photocatalysis assisted chemical mechanical polishing for 2 hours, the silicon carbide wafer obtains a high quality surface with the surface roughness at Ra 0.528 nm The material removal rate is 0.96 μm/h in fine polishing process, which is significantly influenced by factors such as ultraviolet irradiation, electron capture agent (H2O2) and acidic environment. This combined method can effectively reduce the surface roughness and improve the polishing efficiency on silicon carbide and other hard-inert materials.

scholarly journals Study on the Influence of Sapphire Crystal Orientation on Its Chemical Mechanical Polishing

2020 ◽  
Vol 10 (22) ◽  
pp. 8065
Author(s):  
Linlin Cao ◽  
Xiang Zhang ◽  
Julong Yuan ◽  
Luguang Guo ◽  
Teng Hong ◽  
...  
Keyword(s):  
Material Removal Rate ◽  
Material Properties ◽  
Chemical Mechanical Polishing ◽  
Crystal Orientation ◽  
Material Removal ◽  
Removal Rate ◽  
Substrate Material ◽  
Mechanical Polishing ◽  
Sapphire Crystal ◽  
Research Objects

Sapphire has been the most widely used substrate material in LEDs, and the demand for non-C-planes crystal is increasing. In this paper, four crystal planes of the A-, C-, M- and R-plane were selected as the research objects. Nanoindentation technology and chemical mechanical polishing technology were used to study the effect of anisotropy on material properties and processing results. The consequence showed that the C-plane was the easiest crystal plane to process with the material removal rate of 5.93 nm/min, while the R-plane was the most difficult with the material removal rate of 2.47 nm/min. Moreover, the research results have great guiding significance for the processing of sapphire with different crystal orientations.

Effect of Different Abrasives on Chemical Mechanical Polishing for Magnesia Alumina Spinel

2020 ◽  
Vol 866 ◽  
pp. 115-124
Author(s):  
Zhan Kui Wang ◽  
Ming Hua Pang ◽  
Jian Xiu Su ◽  
Jian Guo Yao
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Chemical Mechanical Polishing ◽  
Removal Rate ◽  
Mechanical Polishing ◽  
Key Factors ◽  
Particle Size Analyzer ◽  
Scanning Electron ◽  
Shape And Size

In this paper, a series of chemical mechanical polishing (CMP) experiments for magnesia alumina (Mg-Al) spinel were carried out with different abrasives, and the materials removal rate (MRR) and surface quality was evaluated to explore their different effects. The scanning electron microscope (SEM) and laser particle size analyzer were also employed to test the micro-shape and size distribution of abrasives. Then, the mechanism of different effects with different abrasives was analyzed in CMP for Mg-Al spinel. Those experimental results suggest that different subjecting pressure ratios of abrasives to polishing pad with different abrasive are the key factors leading to difference polishing performances in CMP.

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