Study on the Motion Trajectory of Abrasives and Surface Improvement Mechanism in Ultrasonic-Assisted Diamond Wire Sawing Monocrystalline Silicon

At a Glance

Metadata	Details
Publication Date	2025-06-13
Journal	Micromachines
Authors	Honghao Li, Yufei Gao, Shaoming Hu, Zhipu Huo
Institutions	Shandong University
Analysis	Full AI Review Included

Technical Documentation: Surface Quality Enhancement in Ultrasonic-Assisted Diamond Wire Sawing (UADWS)

Executive Summary

This research provides a mechanistic analysis of how Ultrasonic-Assisted Diamond Wire Sawing (UADWS) significantly improves the surface quality of monocrystalline silicon (mono-Si) wafers compared to conventional Diamond Wire Sawing (DWS).

Core Achievement: UADWS successfully reduced both surface roughness (Ra) and wire mark Peak-Valley (PV) height on mono-Si slices.
Quantitative Improvement: Surface roughness (Ra) was reduced by 12.9% (from 0.31 µm to 0.27 µm), and wire mark PV value was reduced by over 50% (from 3.34 µm to 1.65 µm).
Mechanism of Action: Ultrasonic vibration transforms the abrasive trajectory from a straight line (DWS) into an approximately sinusoidal curve (UADWS).
Kinematic Effect: This sinusoidal trajectory increases the abrasive cutting arc length ($l_u$) while simultaneously reducing the abrasive cutting depth ($h_u$).
Material Removal Mode: The reduced cutting depth promotes material removal in the ductile regime, minimizing lateral crack propagation and large-scale spalling associated with brittle fracture.
Surface Morphology: The vibration induces a micro-grinding effect on the peaks and valleys of wire marks, resulting in a higher surface flatness characterized by numerous, small, uniformly distributed micro-pits instead of large, deep pits and parallel scratches.

Technical Specifications

The following hard data points were extracted from the experimental conditions and results comparing DWS and UADWS of mono-Si.

Parameter	Value	Unit	Context
Workpiece Material	Monocrystalline Silicon (mono-Si)	N/A	10 mm x 10 mm specimen
Wire Saw Diameter	220	µm	Electroplated diamond wire
Wire Saw Length	70	m	Experimental setup
Workpiece Feed Speed ($v_w$)	0.4	mm/min	Constant for DWS and UADWS
Wire Speed ($v_s$)	1200	m/min	Constant for DWS and UADWS
Ultrasonic Frequency ($f$)	20	kHz	UADWS condition
Ultrasonic Amplitude ($A$)	18	µm	UADWS condition
DWS Surface Roughness (Ra)	0.31	µm	Conventional DWS result
UADWS Surface Roughness (Ra)	0.27	µm	12.9% reduction
DWS Wire Mark PV Value	3.34	µm	Conventional DWS result
UADWS Wire Mark PV Value	1.65	µm	50.6% reduction

Key Methodologies

The study utilized a combination of theoretical modeling and comparative experimental validation to analyze the UADWS process.

Kinematic Modeling: Established a two-dimensional coordinate rotation rule to model the motion trajectory of single and multiple abrasives relative to the workpiece under ultrasonic vibration.
Trajectory Simulation: Used MATLAB (2021a) to visualize the abrasive motion, demonstrating the transition from a linear trajectory (DWS) to a sinusoidal trajectory (UADWS).
Parameter Analysis: Calculated the influence of wire speed ($v_s$) and ultrasonic amplitude ($A$) on the abrasive cutting arc length ($l_u$) and cutting depth ($h_u$), confirming that UADWS increases $l_u$ and decreases $h_u$.
Experimental Setup: Utilized a diamond single-wire reciprocating cutting machine (SH300) equipped with an ultrasonic system (generator, amplitude transformer, horn).
Comparative Slicing: Sliced mono-Si specimens under two conditions: DWS ($A=0$ µm) and UADWS ($A=18$ µm), keeping $v_w$ (0.4 mm/min) and $v_s$ (1200 m/min) constant.
Surface Metrology: Measured surface morphology, roughness (Ra), and wire mark PV values across five points on each slice using a laser confocal microscope (Keyence VK-X200K) at 1000x magnification.

6CCVD Solutions & Capabilities

The research demonstrates that controlling the abrasive-workpiece interaction through ultrasonic vibration is critical for achieving high surface quality in hard material slicing. 6CCVD, as an expert supplier of MPCVD diamond materials, offers the foundational components and engineering support necessary to replicate, optimize, and extend this UADWS technology to advanced applications.

Applicable Materials for UADWS Tooling and Substrates

While the paper utilized electroplated diamond wire, the highest performance in UADWS is achieved when cutting advanced materials like SiC, GaN, or even diamond itself. 6CCVD provides the necessary high-purity materials:

High-Purity Polycrystalline Diamond (PCD): Ideal for large-area abrasive tools or wear components in the UADWS system (e.g., guide wheels, tension components) where high wear resistance and large dimensions are required. We offer PCD plates/wafers up to 125mm in diameter.
Optical Grade Single Crystal Diamond (SCD): Suitable for developing ultra-precise abrasive grains or for use as high-quality substrates in advanced research where defect density must be minimized. We offer SCD in thicknesses ranging from 0.1 µm to 500 µm.
Boron-Doped Diamond (BDD): Available for applications requiring conductive diamond components, potentially useful for in-situ monitoring or specialized electrochemical UADWS processes.

Customization Potential for Advanced UADWS Development

6CCVD’s in-house manufacturing capabilities directly address the needs of researchers developing next-generation diamond wire saws or processing unique substrates:

Requirement from Research	6CCVD Capability	Technical Advantage
Abrasive Substrate	Custom Diamond Plates/Wafers	SCD/PCD substrates up to 125mm for tool development.
Wire Saw Metalization	Internal Metalization Services	Custom deposition of Au, Pt, Pd, Ti, W, or Cu layers, critical for bonding abrasives or creating specialized wire matrices.
Ultra-Low Roughness	Precision Polishing	Guaranteed surface roughness of Ra < 1 nm (SCD) and Ra < 5 nm (Inch-size PCD), providing ideal metrology standards for UADWS output.
Substrate Thickness	Custom Thicknesses	SCD/PCD thicknesses from 0.1 µm up to 500 µm, and substrates up to 10 mm, supporting diverse slicing requirements.

Engineering Support

6CCVD’s in-house PhD team specializes in the material science and mechanical properties of MPCVD diamond. We offer consultation services to assist engineers and scientists in:

Material Selection: Optimizing diamond grade (SCD vs. PCD) and crystal orientation for specific UADWS applications (e.g., slicing SiC, GaN, or diamond).
Process Optimization: Applying the kinematic principles derived in this study (e.g., optimizing $A$, $v_s$, and $f$) to maximize the ductile removal regime for novel materials.
Global Logistics: Ensuring reliable, DDU (Delivery Duty Unpaid) default, or DDP (Delivery Duty Paid) global shipping for time-sensitive research projects.

For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.

View Original Abstract

The surface quality of diamond wire sawing (DWS) wafers directly affects the efficiency and yield of subsequent processing steps. This paper investigates the motion trajectory of abrasives in ultrasonic-assisted diamond wire sawing (UADWS) and its mechanism for improving surface quality. The influence of ultrasonic vibration on the cutting arc length, cutting depth, and interference of multi-abrasive trajectories was analyzed through the establishment of an abrasive motion trajectory model. The ultrasonic vibration transforms the abrasive trajectory from linear to sinusoidal, thereby increasing the cutting arc length while reducing the cutting depth. A lower wire speed was found to be more conducive to exploiting the advantages of ultrasonic vibration. Furthermore, the intersecting interference of multi-abrasive trajectories contributes to enhanced surface quality. Experimental studies were conducted on monocrystalline silicon (mono-Si) to verify the effectiveness of ultrasonic vibration in improving surface morphology and reducing wire marks during the sawing process. The experimental results demonstrate that, compared with DWS, UADWS achieves a significantly lower surface roughness Ra and generates micro-pits. The ultrasonic vibration induces a micro-grinding effect on both peaks and valleys of wire marks, effectively reducing their peak-valley (PV) height. This study provides a theoretical basis for optimizing UADWS process parameters and holds significant implications for improving surface quality in mono-Si wafer slicing.

Tech Support

Original Source

DOI: https://doi.org/10.3390/mi16060708

References

2025 - Bridging efficiency and scalability: A systematic evaluation of diamond wire sawn silicon wafer texturing technologies for high-performance photovoltaics [Crossref]
2022 - Direct solar-driven reduction of greenhouse gases into hydrocarbon fuels incorporating thermochemical energy storage via modified calcium looping [Crossref]
2024 - Effect of nano-scratch speed on removal behavior of single crystal silicon
2021 - Science and art of ductile grinding of brittle solids [Crossref]
2024 - Fractal analysis on the surface topography of Monocrystalline silicon wafers sawn by diamond wire [Crossref]
2019 - Surface characteristics and wire wear of electroplated diamond wire saw slicing photovoltaic polycrystalline silicon
2013 - Study on ultrasonic vibration cutting of monocrystal silicon material with electroplated diamond wire saw
2022 - Prediction and verification of wafer surface morphology in ultrasonic vibration assisted wire saw (UAWS) slicing single crystal silicon based on mixed material removal mode [Crossref]
2023 - Theoretical and experimental investigations of surface generation induced by ultrasonic assisted grinding [Crossref]