A Three-Dimensional Hydrodynamic Lubrication Model for Chemical-Mechanical Polishing Considering Pad Roughness

2010 ◽  
Vol 44-47 ◽  
pp. 1213-1217
Author(s):  
Fei Yan Lou
Keyword(s):  
Experimental Data ◽  
Film Thickness ◽  
Tilt Angle ◽  
Chemical Mechanical Polishing ◽  
Applied Load ◽  
Rotation Speed ◽  
Hydrodynamic Lubrication ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model

A three-dimensional hydrodynamic lubrication model based on lubrication theory is developed which accounts for pad roughness and slurry flow. The distribution of the slurry film thickness and pressure between the pad and the wafer are predicted using the model. The effects of the pad roughness, the polishing applied load and rotation speed on slurry film thickness and tilt angle are discussed. At last, a CMP experiment is carried out. It is found that the results are proved the three-dimensional model considering pad roughness agrees well with our experimental data. The results improve the previous models so that the CMP process can be better simulated using the model. Furthermore, they are useful in the processing of CMP and the design of the pad roughness.

Numerical and Experimental Research of the Slurry Film in Chemical Mechanical Polishing (CMP)

2010 ◽  
Vol 102-104 ◽  
pp. 669-674
Author(s):  
Fei Yan Lou ◽  
Qian Fa Deng ◽  
Ju Long Yuan
Keyword(s):  
Film Thickness ◽  
Chemical Mechanical Polishing ◽  
Applied Load ◽  
Reynolds Equation ◽  
Rotation Speed ◽  
Hydrodynamic Lubrication ◽  
Three Dimensional ◽  
Mechanical Polishing ◽  
Film Pressure ◽  
Minimum Film Thickness

A three-dimensional hydrodynamic lubrication model for chemical-mechanical polishing is presented based on the Reynolds equation and Reynolds boundary condition. By solving the Reynolds equation, the slurry film pressure distribution has been obtained. The effects of minimum film thickness and the wafer tile angle on the film pressure are analyzed, and the influence of the polishing applied load and rotation speed on slurry film thickness and tilt angle are discussed. At last, by experiment, it is found that the simulation results are similar to experiment results which film thickness is increasing with the increasing of rotation speed, decreasing of the applied load. It is proved that the simulation is reliable.

Modeling and Kinematics Simulation of HT-CVT Based on Virtual Prototype Technology

2010 ◽  
Vol 44-47 ◽  
pp. 884-888
Author(s):  
Qing Gong Zhang ◽  
Hua Li ◽  
Jin Yao
Keyword(s):  
Hydrodynamic Lubrication ◽  
Three Dimensional ◽  
Gear Ratio ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Traction Drive ◽  
Kinematics Simulation ◽  
Contact Constraint ◽  
Variable Transmission ◽  
Angular Velocities

The three-dimensional model of a Half Toroidal Continuously Variable Transmission (HT-CVT) was established by CAXA solid design. The kinematics simulation of the HT-CVT was realized by replacing the traction drive of elasto-hydrodynamic lubrication (EHL) oil film with the contact constraint joints in ADAMS. The angular velocity curves of the power rollers and the output cone disk on the HT-CVT were obtained. Simulation results demonstrate the fluctuation of the angular velocities on the two power rollers and the output cone disk compares well with the conclusion derived from the actual gear ratio of the HT-CVT.

Stable Platform Based on Workbench Vehicle Structure Analysis

2013 ◽  
Vol 477-478 ◽  
pp. 132-134
Author(s):  
Jin Xia Liu ◽  
Chong Chen ◽  
Liang Wang ◽  
Cong Zhang
Keyword(s):  
Numerical Analysis ◽  
Structural Analysis ◽  
Structure Analysis ◽  
Tilt Angle ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Vehicle Structure ◽  
Platform Tilt

This paper has conducted a structural analysis by workbench after establishing a stable platform for automotive three-dimensional model, primarily concerning whether the platform can provide a benchmark to meet the requirements of equipment, including the numerical analysis of whether the platform tilt angle under load can achieve the requirements as well as the scheme of improvement direction of the structure.

The Numerical Simulation Research of Gas Entrainment Based on Three-Dimensional Model

2017 ◽  
Author(s):  
Yilin Zhang ◽  
Shanfang Huang
Keyword(s):  
Experimental Data ◽  
Mass Flow Rate ◽  
Cross Section ◽  
Flow Rate ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Gas Entrainment ◽  
Simulation Results

Two kinds of three-dimensional model are built to simulate the gas entrainment process through a small break in the horizontal coolant pipe at the bottom of the stratified flow. The results were compared with the two-dimensional simulation results and the experimental data. In terms of the two-phase distribution, the simulation results agree well with the experimental data and show much superiority compared with the two-dimensional model. The results verify the reliability of model building, condition setting and calculating method qualitatively and quantitatively. In general, after gas entrainment, the average velocity over cross section increases obviously, but the mass flow rate decreases contrarily. This is because that void fraction meanwhile reduces the fluid density. In addition, it is found that the larger the void fraction of vapor is, the higher the average discharge velocity of the fracture cross-section fluid is. Besides, with the larger internal and external pressure difference, the gas volume fraction and the flow velocity in the break increase, resulting in the mass flow rate increasing along with them. However, since the critical height increases as well, the total loss amount of liquid in the stable effluent stage decreases, and the time before entrainment becomes shorter.

Numerical and Experimental Analysis for Large Radius Deformation of Stainless Steels by Laser Forming Process

2005 ◽  
Author(s):  
J. Pennuto ◽  
J. Choi
Keyword(s):  
Experimental Data ◽  
Phase Transformation ◽  
Experimental Testing ◽  
Three Dimensional ◽  
Laser Forming ◽  
Bend Angle ◽  
Large Radius ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Forming Process

In an effort to develop a process free of dedicated tooling, this research seeks to study large radius deformation by laser forming. Experimental testing was conducted to determine how the laser parameters affect the single pass output bend angle as well as the additive bend angle from successive parallel, evenly spaced laser irradiations. As an extension of the previous developments, this work seeks to develop a three-dimensional model to simulate the multi-scan laser process. It is of interest to determine how sophisticated a three-dimensional case is required for sufficient agreement to experimental data. The simulated results of bending angle are compared with experimental data and suggestions for future study include the implementation of phase transformation and microstructure data within the model to account for stress development resulting from phase transformation and grain growth.

The Effects of Three-Dimensional Model Surface Roughness Features on Lubricant Film Thickness in EHL Contacts

2003 ◽  
Vol 125 (3) ◽  
pp. 533-542 ◽  
Author(s):  
Jian W. Choo ◽  
Romeo P. Glovnea ◽  
Andrew V. Olver ◽  
Hugh A. Spikes
Keyword(s):  
Surface Roughness ◽  
Film Thickness ◽  
Three Dimensional ◽  
Lubricant Film ◽  
Imaging Method ◽  
Dimensional Model ◽  
Lubricant Film Thickness ◽  
Model Surface ◽  
Three Dimensional Model ◽  
Spacer Layer

The Spacer Layer Imaging method has been used to investigate the influence of three-dimensional roughness features on the thickness and shape of elastohydrodynamic (EHL) films. An array of near-hemispherical bumps was employed to represent asperities. A micro-EHL film developed at the bumps whose orientation depended on that of the inlet boundary at the location at which the bump had entered the contact. Rolling-sliding conditions induced a micro-EHL film with a classical horseshoe shape at the bumps. The flow of lubricant around the bumps appeared to differ between thin and thick films.

Liquid Flow Characteristics in Microchannels

2011 ◽  
Vol 130-134 ◽  
pp. 1484-1490
Author(s):  
Yan Feng Liu ◽  
Hong Wei Li ◽  
Jing Wei Zhang ◽  
Jin Xue
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Fluid Flow ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Simulation Methods ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Simulation Results ◽  
Poiseuille Number

A three-dimensional model was developed to simulate the laminar flow and convective heat transfer in rectangular silicon microchannels，which have hydraulic diameter of 95.3，92.3 ,85.8 , 80 and 75μm respectively．The rationality of the simulation methods and results were validated by comparing with experimental data. The simulation results indicate that the aspect ratio has a significant impact on the Poiseuille number. Conventional fluid flow theory is fit for researching the fluid flow in microchannels, Po is a constant that is not dependent on the Reynolds number.

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