Aluminium Nitride Surface Characterization by Grinding with Laser-Ultrasonic Coupling

Area of Science:

• Materials Science and Engineering
• Surface Machining and Tribology
• Microelectronics Manufacturing

Background:

• Aluminium nitride (AlN) is crucial for heat dissipation in electronics but suffers from anisotropy and brittleness, limiting surface integrity and increasing grinding forces.
• Increasing demands for dimensional accuracy, machining efficiency, and surface quality in microelectronics necessitate advanced machining solutions for AlN.

Purpose of the Study:

• To investigate a novel laser-ultrasonic-assisted grinding (LUAG) process for aluminium nitride (AlN) substrates.
• To systematically analyze the effects of LUAG on grinding force, stress distribution, damage mechanisms, and subsurface damage depth.

Main Methods:

• Molecular dynamics (MD) simulations were employed to model the LUAG process for AlN.
• Experimental verification was conducted to validate simulation findings on grinding force, stress, damage, and subsurface characteristics.

Main Results:

• LUAG reduced grinding forces by 50% compared to traditional grinding (TG).
• Microhardness of AlN increased to over 1200 HV, with a 42.6% reduction in friction and wear coefficient.
• LUAG resulted in low subsurface damage depth, promoting material hardening and wear resistance, with interlaced dislocation lines indicating phase transformation potential.

Conclusions:

• The synergistic combination of laser, ultrasonic vibration, and abrasive processing in LUAG enhances understanding of material behavior under complex machining conditions.
• LUAG is a highly effective method for achieving high-performance machining of aluminium nitride substrate surfaces, improving material properties and surface quality.