Low Defect Ceria for ILD CMP

ABSTRACTThe reduction of wafer scratching is a key goal driving the commercial development of CMP slurries. To better understand the underlying abrasive particle properties critical to the scratch performance of ILD CMP slurries, the scratching behavior of ceria slurries prepared with a range of particle size characteristics are characterized. Scratch results are presented and two effects are proposed to account for the findings. The Removal Rate Effect relies solely on the observed inverse proportionality between scratching and removal rate. This interpretation is consistent with a simple surface balance of scratches but suggests that removal rate differences dominate scratch performance. The Managed Tail Effect considers the effect of particle characteristics on both the creation and the removal of scratches. For a given particle population, the larger particles are assumed to dominate scratch creation. However, larger particles are also seen to drive removal rate which affects the removal of scratches during polishing. This interpretation implies that optimal scratch performance for a ceria ILD CMP slurry will be obtained when the width of the ceria particle's size distribution is optimized relative to its mean.

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The effect of load and abrasive particle size on the material removal rate of silicon nitride artefacts

Ceramics International ◽

10.1016/0272-8842(95)96209-8 ◽

1995 ◽

Vol 21 (5) ◽

pp. 355-366 ◽

Cited By ~ 8

Author(s):

T.A. Stolarski ◽

E. Jisheng ◽

D.T. Gawne ◽

S. Panesar

Keyword(s):

Particle Size ◽

Silicon Nitride ◽

Material Removal Rate ◽

Material Removal ◽

Removal Rate ◽

Abrasive Particle

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Effect of Abrasive Particle Size on Lapping of Sapphire Wafer by Fixed Abrasive Pad

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.764.106 ◽

2018 ◽

Vol 764 ◽

pp. 106-114

Author(s):

Jian Bin Wang ◽

Zhen Li ◽

Yong Wei Zhu ◽

Ben Chi Jiang ◽

Pei Cheng Shi

Keyword(s):

Particle Size ◽

Penetration Depth ◽

Material Removal ◽

Removal Rate ◽

Abrasive Particle ◽

Work Piece ◽

Average Surface Roughness ◽

Sapphire Wafer ◽

Fixed Abrasive Pad ◽

Fixed Abrasive

The choice of abrasive particle size is crucial to improve the lapping efficiency and surface quality in lapping of sapphire wafer by fixed abrasive (FA) pad. A model for the penetration depth of a single abrasive is developed with fixed abrasive pad. A serious of lapping tests were carried out using FA pads embedded with different size of diamond particles to verify the validity of the developed model. Results show that the penetration depth of abrasive is related not only to the particle size, but to the hardness ratio of the work-piece to the pad as well. The material removal rate of sapphire is proportional to the square of abrasive particle size, while the average surface roughness is proportional to the abrasive particle size.

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Preparation and Processing Performance of Viscoelastic Abrasive Flow

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.546.55 ◽

2013 ◽

Vol 546 ◽

pp. 55-59

Author(s):

Lu Yang ◽

Ke Hua Zhang ◽

Guang Zhen Zheng ◽

Hang Guo

Keyword(s):

Surface Roughness ◽

Silicon Carbide ◽

Particle Size ◽

Silicone Oil ◽

Removal Rate ◽

Abrasive Particle ◽

Viscosity Coefficient ◽

Advanced Technology ◽

Dielectric Characteristics ◽

Workpiece Surface

Abstract. Abrasive flow machining (AFM) is an advanced technology which can improve the uniform consistency of profiled surface. First, the dielectric characteristics of the abrasive flow (the medium features include medium types, medium viscosity coefficient, the concentration of medium and abrasive, abrasive type, abrasive size) is studied, abrasive flow including different medium is deployed by mixing and mix well of the polymer silicone fluid, silicone oil, wax, and other fats, and adding silicon carbide with different particle size and mixed for processing experiment. Within the limits of the workpiece polishing, the change direction of the surface roughness and the removal rate of workpiece surface are substantially same and approaching the linear relationship, the lowest surface roughness Ra of SiC (abrasive particle size is 200#) reduced from 3.5μm to 0.5μm. The hardness and durability of the silicon carbide abrasive in this study is quite good, and the price is low, the processing characteristics are quite consistent with the economic costs on the demand.

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Effects of Nano-scale Colloidal Abrasive Particle Size on SiO2 by Chemical Mechanical Polishing

MRS Proceedings ◽

10.1557/proc-671-m1.6 ◽

2001 ◽

Vol 671 ◽

Cited By ~ 6

Author(s):

Chunhong Zhou ◽

Lei Shan ◽

S.H. Ng ◽

Robert Hight ◽

Andrew. J. Paszkowski ◽

...

Keyword(s):

Particle Size ◽

Material Removal Rate ◽

Surface Finish ◽

Material Removal ◽

Removal Rate ◽

Abrasive Particle ◽

Single Crystal Silicon ◽

Weight Percent ◽

Crystal Silicon ◽

P Type

ABSTRACTThis paper reports on the effect of colloidal abrasive particle size in the polishing of thermally grown silicon dioxide on 100mm diameter, P-type, (100), single crystal silicon wafers. The abrasive particle sizes were varied in six (6) slurries with pH values of 10.97 ± 0.08. The abrasive sizes were 10, 20, 50, 80, 110 and 140nm in diameter, and the slurry contained 30 weight percent abrasives. The experimental results indicate that the material removal rate (MRR) varies with the volume of the particle size. Results also confirm that there exists an optimum abrasive particle size with respect to material removal rate and surface finish. For a pad surface roughness of 5.2μm (Ra), the slurry containing 80nm particles resulted in the highest material removal rate and best surface finish. A nano-film model based on the pad roughness is used to explain the results.

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Micro Ultrasonic Machining Using Oil Based Abrasive Slurry

ASME 2008 International Manufacturing Science and Engineering Conference, Volume 2 ◽

10.1115/msec_icmp2008-72138 ◽

2008 ◽

Cited By ~ 4

Author(s):

Murali M. Sundaram ◽

Sreenidhi Cherku ◽

K. P. Rajurkar

Keyword(s):

Particle Size ◽

Material Removal Rate ◽

Surface Finish ◽

Material Removal ◽

Removal Rate ◽

Abrasive Particle ◽

High Wear Resistance ◽

Ultrasonic Machining ◽

Influence Of Process Parameters ◽

Slurry Concentration

Advanced engineering materials posses excellent properties such as high wear resistance, and inertness to corrosion and chemical reactions. Since these materials are usually hard, brittle, chemically inert, and electrically nonconductive, they pose serious machinability challenges. Micro ultrasonic machining (Micro USM) is an emerging method for the micromachining of hard and brittle materials without any thermal damage. This paper presents the results of micro ultrasonic machining using oil based abrasive slurry. Details of the in-house built experimental setup used to conduct the experiments are explained. The influence of process parameters such as slurry medium, slurry concentration, and abrasive particle size on the performance of micro USM are reported. It was noticed that the evidence of three body material removal mechanism is predominant for micro USM using oil based slurry. In general, the material removal rate increases with the increase in the abrasive particle size for both aqueous abrasive slurry and oil based abrasive slurry. Further, material removal rate is consistently higher for experiments conducted with aqueous abrasive slurry medium. On the other hand, it is noticed that the oil based slurry medium provides better surface finish. It is also noticed that the smaller abrasive grains provide better surface finish for both aqueous, and oil based abrasive slurry mediums. Role of slurry concentration is ambiguous, as no clear trend of its effect of on process performance is evident in the available experimental results.

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A Scratch Intersection Model of Material Removal During Chemical Mechanical Planarization (CMP)

Journal of Manufacturing Science and Engineering ◽

10.1115/1.1949616 ◽

2004 ◽

Vol 127 (3) ◽

pp. 545-554 ◽

Cited By ~ 38

Author(s):

Wei Che ◽

Yongjin Guo ◽

Abhijit Chandra ◽

Ashraf Bastawros

Keyword(s):

Particle Size ◽

Material Removal ◽

Removal Rate ◽

Chemical Mechanical Planarization ◽

Abrasive Particle ◽

Interaction Mechanism ◽

Local Deformation ◽

Deformation Pattern ◽

Proposed Model ◽

Intersection Model

A scratch intersection based material removal mechanism for CMP processes is proposed in this paper. The experimentally observed deformation pattern by SEM and the trends of the measured force profiles (Che et al., 2003) reveal that, for an isolated shallow scratch, the material is mainly plowed sideway along the track of the abrasive particle with no net material removal. However, it is observed that material is detached close to the intersection zone of two scratches. Motivated by this observation, it is speculated that the deformation mechanism changes from ploughing mode to shear-segmentation mode as the abrasive particle approaches the intersection of two scratches under small indentation depth for ductile metals. The proposed mechanistic material removal rate (MRR) model yields Preston constant similar to those observed experimentally for CMP processes. The proposed model also reveals that the nature of the slurry-pad interaction mechanism, and its associated force partitioning mechanism, is important for determining the variation of MRR with particle size and concentration. It is observed that under relatively soft pads, small particles and low particle concentration, the pad undergoes local deformation, yielding an increased MRR with increasing particle size and concentration. At the other extreme, the intact walls of the surface cells and the connecting cell walls between the surface pores deform globally, resembling a beam or a plate, and a decreasing trend in MRR is observed with increasing particle size and concentration. The predicted MRR trends are compared to existing experimental observations.

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The Optimization of Lapping Process Parameters Based on Extension Theory

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.531-532.262 ◽

2012 ◽

Vol 531-532 ◽

pp. 262-265

Author(s):

Fan Jiang ◽

Jian Hua Xiang ◽

Zhong Wei Liang ◽

Chun Liang Zhang

Keyword(s):

Particle Size ◽

Process Parameters ◽

Removal Rate ◽

Abrasive Particle ◽

Optimization Theory ◽

Parameters Optimization ◽

Slurry Flow ◽

Load Pressure ◽

Fluid Concentration ◽

Optimum Solution

This paper introduced Extension optimization theory into the parameters optimization of lapping process, the five process parameters of the lapping load pressure, the platen speed, the abrasive particle size, slurry flow, lapping fluid concentration are considered, the target extension decision models and integrated decision-making correlation function are established. According to the selection criteria, the optimum solution is obtained. The results showed that: as the lapping speed of 35rpm, the pressure of 11 MPa, the abrasive particle size of W7.95, the slurry flow rate of 228.75ml/min, the slurry concentration of 25%, the surface removal rate increased, the surface roughness decreases, flatness decreases.

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Effect of Abrasive Waterjet Parameters on Volume Removal Trends in Turning

Journal of Engineering for Industry ◽

10.1115/1.2803524 ◽

1995 ◽

Vol 117 (4) ◽

pp. 475-484 ◽

Cited By ~ 20

Author(s):

A. I. Ansari ◽

M. Hashish

Keyword(s):

Experimental Investigation ◽

Particle Size ◽

Flow Rate ◽

Removal Rate ◽

Abrasive Particle ◽

Sweep Rate ◽

Abrasive Waterjet ◽

Orifice Diameter ◽

Abrasive Waterjets ◽

Rate Limit

An experimental investigation was conducted to investigate the influence of abrasive waterjet parameters on the volume removal rate in abrasive waterjet turning. Abrasive mass flow rate, abrasive particle size, waterjet pressure, and orifice diameter were the principal variables that were investigated. Limited tests were also conducted with abrasive mixtures. The results show that the volume removal trends in abrasive waterjet turning are similar to those in linear cutting with abrasive waterjets. Increasing waterjet pressure, orifice diameter, and abrasive flow rate generally resulted in an increase in volume removal rate. However, the volume removal rate levels off either due to volume sweep rate limit or due to the abrasive waterjet limit. The results also suggest a potential for optimizing the abrasive flow rate and abrasive composition. The volume removal rate showed only a weak dependence on the abrasive particle size.

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