Computer-aided analysis of cutting processes for brittle materials
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2017-01-01 |
| Journal | AIP conference proceedings |
| Authors | A. I. Ogorodnikov, Đ. Đ. ĐąĐžŃ ĐŸĐœĐŸĐČ |
| Institutions | Ural Federal University |
| Citations | 2 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Diamond Machining of Brittle Materials
Section titled âTechnical Documentation & Analysis: Diamond Machining of Brittle MaterialsâThis documentation analyzes the research on computer-aided analysis of cutting processes for brittle materials, focusing on the requirements for high-precision diamond tools and substrates, and aligning them with 6CCVDâs advanced MPCVD diamond capabilities.
Executive Summary
Section titled âExecutive Summaryâ- Application Focus: 3D Finite Element Analysis (FEA) was successfully used to model and simulate ultra-precision diamond scribing and dicing processes on brittle materials, specifically silicon wafers.
- Tool Geometry Validation: The study validated the use of a four-sided pyramid diamond tool (Berkovich geometry) with a 120° included angle and a 15° inclination angle, confirming these parameters minimize chipping and defect propagation.
- Critical Stress Control: The FE model accurately calculated the distribution of stress intensity and tangential stresses, demonstrating that internal stresses and defect dimensions are critically dependent on the diamond tip radius and applied normal force (0.1 N to 1 N range).
- Quality Requirement: The primary engineering goal is to achieve a minimal defect zone near the scratch line and ensure safe separation, necessitating diamond tools capable of maintaining nanoscale edge radii for ductile mode machining.
- Verification Method: The numerical model was verified against full-scale experiments using optical microscopy (infrared and dark-field techniques), confirming scratch widths of approximately 10 ”m under low load conditions.
- 6CCVD Value Proposition: This research underscores the absolute necessity of high-purity, ultra-hard Single Crystal Diamond (SCD) for manufacturing the precision tools required to replicate or advance these ultra-precision machining techniques.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the simulation and experimental verification of the scribing process:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Tool Geometry Type | Four-sided pyramid | N/A | Corresponds to Berkovich indenter |
| Tool Included Angle | 120 | ° | Large included angle used for simulation |
| Tool Inclination Angle | 15 | ° | Angle to the normal axis; cutting possible with inclination less than 15° |
| Applied Loading Force Range | 0.1 to 1 | N | Normal force applied during scribing |
| Visible Scratch Width (0.1 N load) | ~10 | ”m | Measured via optical microscopy |
| Crystallographic Direction | [-1-1 2] | N/A | Direction of scribing on single Si crystal |
| Stress Calculation Accuracy | Up to 4 | % | Correspondence to theoretical values for silicon |
| Minimum Chipping Requirement | < 15 | ° | Inclination angle required for minimum chipping |
Key Methodologies
Section titled âKey MethodologiesâThe research combined advanced computational modeling with experimental verification to analyze the mechanics of brittle material cutting.
- Computational Modeling: 3D computer simulation of the cutting process was performed using ANSYS CAE (Computer-Aided Engineering) software.
- Parametric Geometry: A parametric model of the silicon workpiece and the diamond tool was created using the ANSYS APDL (ANSYS Parametric Design Language) pre-processor.
- Boundary Conditions: The silicon plate was modeled as being glued to a flexible film with a z-fixed support constraint. Force loading (0.1 N to 1 N) was applied along the z-axis (normal force).
- Tool Specification: The diamond tool was modeled as a four-sided pyramid with a 120° included angle and a 15° inclination angle to the normal axis.
- Stress Analysis: The model calculated the distribution of stress intensity (maximum shear stresses) and tangential stresses, focusing on the compression zone under the diamond tip and the tension area on the surface (where cracking initiates).
- Experimental Verification: Scratches were produced on silicon wafers using a corresponding diamond tip. The resulting surfaces were analyzed using optical microscopy with special add-on devices for infrared and dark-field techniques to verify defect dimensions and model accuracy.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThis research confirms that the success of ultra-precision machining, scribing, and dicing of brittle materials hinges entirely on the quality and geometric precision of the diamond tool. 6CCVD is uniquely positioned to supply the necessary MPCVD diamond materials and customization services to support and extend this research.
| Research Requirement | 6CCVD Applicable Materials & Services | Technical Advantage for Researchers |
|---|---|---|
| Ultra-Hard Tool Material (Berkovich Indenter Geometry) | Optical Grade Single Crystal Diamond (SCD) | SCD provides the highest purity and crystallographic consistency required to manufacture tools that maintain the critical 120° angle and nanoscale tip radius necessary for ductile mode machining. |
| Analysis of Coated/Layered Workpieces | Custom Metalization Services | The paper mentions analyzing coatings. 6CCVD offers in-house metalization (Au, Pt, Pd, Ti, W, Cu) on SCD or PCD substrates, allowing researchers to test adhesion and stress propagation on custom layered diamond components or test fixtures. |
| Large-Scale Wafer Processing (Dicing/Scribing Platforms) | Polycrystalline Diamond (PCD) Plates | We supply PCD plates/wafers up to 125mm in diameter and up to 500”m thick, ideal for use as high-stiffness, wear-resistant platforms or components in large-scale machining systems. |
| Achieving Ductile Mode Machining (Minimal Defect Zone) | Ultra-Precision Polishing (Ra < 1nm) | 6CCVD guarantees SCD polishing to Ra < 1nm. This ensures the diamond tool blank has the surface quality necessary to achieve the minimum cutting edge radius, which is critical for maintaining small chip thickness and preventing crack propagation. |
| Custom Tool Dimensions & Substrates | Custom Dimensions and Thickness | We provide SCD and PCD wafers in thicknesses ranging from 0.1”m to 500”m, and substrates up to 10mm thick, allowing for precise material selection based on required tool stiffness and geometry. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in the material science of diamond for extreme applications. We can assist engineers and scientists with material selection, crystallographic orientation, and surface preparation (polishing and metalization) for similar ultra-precision machining, scribing, and optical component projects.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
This paper is focused on 3D computer simulation of cutting processes for brittle materials and silicon wafers. Computer-aided analysis of wafer scribing and dicing is carried out with the use of the ANSYS CAE (computer-aided engineering) software, and a parametric model of the processes is created by means of the internal ANSYS APDL programming language. Different types of tool tip geometry are analyzed to obtain internal stresses, such as a four-sided pyramid with an included angle of 120° and a tool inclination angle to the normal axis of 15°. The quality of the workpieces after cutting is studied by optical microscopy to verify the FE (finite-element) model. The disruption of the material structure during scribing occurs near the scratch and propagates into the wafer or over its surface at a short range. The deformation area along the scratch looks like a ragged band, but the stress width is rather low. The theory of cutting brittle semiconductor and optical materials is developed on the basis of the advanced theory of metal turning. The fall of stress intensity along the normal on the way from the tip point to the scribe line can be predicted using the developed theory and with the verified FE model. The crystal quality and dimensions of defects are determined by the mechanics of scratching, which depends on the shape of the diamond tip, the scratching direction, the velocity of the cutting tool and applied force loads. The disunity is a rate-sensitive process, and it depends on the cutting thickness. The application of numerical techniques, such as FE analysis, to cutting problems enhances understanding and promotes the further development of existing machining technologies. © 2017 Author(s).