Finite Element Analysis on Soft-Pad Grinding of Wire-Sawn Silicon Wafers

2002 ◽  
Author(s):  
X. J. Xin ◽  
Z. J. Pei ◽  
Wenjie Liu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Material Properties ◽  
Silicon Wafers ◽  
Semiconductor Material ◽  
Surface Grinding ◽  
High Quality ◽  
Element Analysis ◽  
Conventional Grinding

Silicon is the primary semiconductor material used to fabricate microchips. The quality of microchips depends directly on the quality of starting silicon wafers. A series of processes are required to manufacture high quality silicon wafers. Surface grinding is one of the processes used to flatten the wire-sawn wafers. A major issue in grinding of wire-sawn wafers is the reduction and elimination of wire-sawing induced waviness. Several approaches (namely, combination of grinding and lapping, reduced chuck vacuum, soft-pad, and wax mounting) have been proposed to address this issue. The results of finite element analysis modeling of these approaches have shown that soft-pad grinding is the most promising approach since it is very effective in reducing the waviness and very easy to be adopted to conventional grinding environment. This paper presents a study of finite element analysis on soft-pad grinding of wire-sawn silicon wafers, covering the mechanisms of waviness reduction and the effects of pad material properties.

Finite Element Analysis on Soft-Pad Grinding of Wire-Sawn Silicon Wafers

2004 ◽  
Vol 126 (2) ◽  
pp. 177-185 ◽  
Author(s):  
X. J. Xin ◽  
Z. J. Pei ◽  
Wenjie Liu
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Material Properties ◽  
Silicon Wafers ◽  
Semiconductor Material ◽  
Surface Grinding ◽  
High Quality ◽  
Element Analysis ◽  
Conventional Grinding

Silicon is the primary semiconductor material used to fabricate microchips. The quality of microchips depends directly on the quality of starting silicon wafers. A series of processes are required to manufacture high quality silicon wafers. Surface grinding is one of the processes used to flatten the wire-sawn wafers. A major issue in grinding of wire-sawn wafers is the reduction and elimination of wire-sawing induced waviness. Several approaches (namely, combination of grinding and lapping, reduced chuck vacuum, soft-pad, and wax mounting) have been proposed to address this issue. Finite element analysis modeling of these approaches was conducted and the results were published earlier. It was shown that soft-pad grinding was a very promising approach since it was very effective in reducing the waviness and very easily adopted to conventional grinding environment. This paper presents a study of finite element analysis on soft-pad grinding of wire-sawn silicon wafers, covering the mechanisms of waviness reduction and the effects of pad material properties.

Chemical Mechanical Polishing of Silicon Wafers: Finite Element Analysis of Wafer Flatness

2005 ◽  
Author(s):  
X. H. Zhang ◽  
Z. J. Pei ◽  
Graham R. Fisher
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Integrated Circuits ◽  
Chemical Mechanical Polishing ◽  
Silicon Wafers ◽  
Mechanical Polishing ◽  
High Quality ◽  
Element Analysis ◽  
Polishing Pressure

Silicon is the primary semiconductor material used to fabricate integrated circuits. The quality of microchips depends directly on the quality of silicon wafers. A series of processes are required to manufacture the high-quality silicon wafers. Chemical mechanical polishing is a necessary step to achieve the required wafer flatness. In this paper, a finite element analysis has been conducted to study the effects of influencing factors (including Young’s modulus and Poisson’s ratio of the polishing pad, thickness of the pad, and polishing pressure) on the wafer flatness.

scholarly journals On the Design of a Biodegradable POC-HA Polymeric Cardiovascular Stent

2012 ◽  
Author(s):  
Joonas Ponkala ◽  
Mohsin Rizwan ◽  
Panos S. Shiakolas
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Material Properties ◽  
Three Dimensional ◽  
Polymeric Composite ◽  
Coronary Stent ◽  
Element Analysis ◽  
Material Models ◽  
Solid Models ◽  
Biodegradable Stents

The current state of the art in coronary stent technology, tubular structures used to keep the lumen open, is mainly populated by metallic stents coated with certain drugs to increase biocompatibility, even though experimental biodegradable stents have appeared in the horizon. Biodegradable polymeric stent design necessitates accurate characterization of time dependent polymer material properties and mechanical behavior for analysis and optimization. This manuscript presents the process for evaluating material properties for biodegradable biocompatible polymeric composite poly(diol citrate) hydroxyapatite (POC-HA), approaches for identifying material models and three dimensional solid models for finite element analysis and fabrication of a stent. The developed material models were utilized in a nonlinear finite element analysis to evaluate the suitability of the POC-HA material for coronary stent application. In addition, the advantages of using femtosecond laser machining to fabricate the POC-HA stent are discussed showing a machined stent. The methodology presented with additional steps can be applied in the development of a biocompatible and biodegradable polymeric stents.

Identification of a Significantly Non-Proportionally Damped Structure Using Force Appropriation

1995 ◽  
Author(s):  
P. S. Holmes ◽  
J. R. Wright ◽  
J. E. Cooper
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Normal Mode ◽  
Normal Modes ◽  
Dynamic Tests ◽  
High Quality ◽  
Element Analysis ◽  
Standard Curve ◽  
Complex Modes ◽  
Phase Resonance

Abstract Dynamic tests were carried out on an aluminium plate with significant non-proportional damping applied via two oil filled dampers. Normal mode force appropriation (phase resonance) methods were used to measure the undamped normal modes of the plate and the results compared with corresponding complex modes obtained using a standard curve fitting (phase separation) approach. It is demonstrated that, as long as suitable excitation positions are chosen, high quality undamped normal modes can be identified while the curve fitted modes are highly complex. A Finite Element analysis of the plate was used to show how the results of normal mode force appropriation are directly comparable, particularly when damping is non-proportional.

Warpage Simulation During Fan-Out Wafer-Level Packaging Process with Uncertainty of Material Properties

2021 ◽  
Vol 21 (5) ◽  
pp. 2987-2991
Author(s):  
Geumtaek Kim ◽  
Daeil Kwon
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Material Properties ◽  
Coefficient Of Thermal Expansion ◽  
Input Output ◽  
Wafer Level ◽  
High Input ◽  
Element Analysis ◽  
Packaging Process ◽  
Wafer Level Packaging

Along with the reduction in semiconductor chip size and enhanced performance of electronic devices, high input/output density is a desired factor in the electronics industry. To satisfy the high input/output density, fan-out wafer-level packaging has attracted significant attention. While fan-out wafer-level packaging has several advantages, such as lower thickness and better thermal resistance, warpage is one of the major challenges of the fan-out wafer-level packaging process to be minimized. There have been many studies investigating the effects of material properties and package design on warpage using finite element analysis. Current warpage simulations using finite element analysis have been routinely conducted with deterministic input parameters, although the parameter values are uncertain from the manufacturing point of view. This assumption may lead to a gap between the simulation and the field results. This paper presents an uncertainty analysis of wafer warpage in fan-out wafer-level packaging by using finite element analysis. Coefficient of thermal expansion of silicon is considered as a parameter with uncertainty. The warpage and the von Mises stress are calculated and compared with and without uncertainty.

Damage Length Predictor for High-Speed Craft

1999 ◽  
Vol 36 (04) ◽  
pp. 203-210
Author(s):  
Steven P. McGee ◽  
Armin Troesch ◽  
Nickolas Vlahopoulos
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Material Properties ◽  
High Speed ◽  
Historical Data ◽  
Element Analysis ◽  
Damage Prediction ◽  
Structural Layout ◽  
Vessel Speed ◽  
Indenter Geometry

In 1994 the International Maritime Organization adopted the Code of Safety for High-Speed Craft (HSC Code). After two years of use, several shortfalls were found, one being the damage length predictor, which is based on traditional steel, mono-hulled vessels. Other damage predictors were developed based on historical data, but they do not account for variables such as aluminum or fiberglass construction, transverse members, indenter geometry variation, or for the case where the vessel comes to rest on the grounding object. This paper proposes a damage prediction model based on material properties, structural layout, grounding object geometry, and vessel speed. The model incorporates four grounding mechanisms: plate cutting, plate tearing, crushing of plate behind transverse members, and transverse member failure. The method is used to determine the resistance energy, compared to the kinetic energy, of the vessel, to determine an effective damage length. Finite-element analysis was used to model the failure of both aluminum and steel transverse members with significant differences in the results. It was found that the transverse members provided the majority of the resistance energy in one grounding mechanism and negligible resistance energy in another.

Sign in / Sign up

Export Citation Format

Share Document