Development of high frequency piezocomposite with hexagonal pillars via cold ablation process.

Ultrasonic transducers are widely used in medical imaging and non-destructive testing. Traditional fabrication methods like the dice-and-fill technique have limitations in achieving high-frequency performance and complex geometries. Prior research has shown that the shape and arrangement of piezoelectric pillars significantly influence transducer performance. However, the variability in pillar design and the ability to achieve smaller structural sizes remain unresolved. This gap motivated the exploration of alternative fabrication techniques. Cold ablation has emerged as a promising method for precision material processing. It allows for high-resolution patterning of piezoelectric materials. The need for improved transducer performance at higher frequencies has driven the search for new fabrication strategies. This paper introduces a novel approach using hexagonal pillars in a 1-3 piezocomposite structure. The study addresses the challenge of achieving both high resonance frequencies and structural flexibility in piezocomposite design.

The aim of this research was to develop a high-frequency ultrasonic transducer using a 1-3 piezocomposite with hexagonal pillars. The specific problem addressed is the limitation of conventional fabrication methods in achieving optimal pillar geometry and structural variability. The motivation stems from the need for improved transducer performance in medical and industrial applications. The study sought to evaluate the cold ablation process as a viable alternative to traditional techniques. The goal was to fabricate a piezocomposite with enhanced resonance frequency and coupling coefficient. The researchers focused on the design and simulation of hexagonal pillars as a novel structural configuration. They aimed to compare the performance of hexagonal pillars against other shapes like square. The study also aimed to demonstrate the feasibility of the cold ablation process in achieving precise and variable pillar designs.

The study employed a cold ablation process using an ultraviolet picosecond laser to fabricate the 1-3 piezocomposite. The hexagonal pillars were designed with an edge length of 10 μm and a height of 36 μm. The kerf width was approximately 5 μm. The design was first simulated to predict performance characteristics. The simulation results guided the fabrication process. The cold ablation technique allowed for precise control over pillar geometry and distribution. The fabricated piezocomposite was integrated into a transducer prototype. The transducer was characterized to evaluate its resonance frequency and coupling coefficient. The performance was compared against conventional techniques like the dice-and-fill method.

The fabricated 1-3 piezocomposite achieved a resonance frequency of 51.2 MHz and a coupling coefficient of 0.69. The hexagonal pillar design outperformed square-shaped pillars in terms of performance metrics. The cold ablation process enabled the creation of smaller and more variable pillar structures. The edge length and height of the hexagonal PZT pillars were precisely 10 μm and 36 μm, respectively. The kerf width was maintained at approximately 5 μm. The transducer prototype demonstrated high-frequency performance suitable for advanced applications. The coupling coefficient of 0.69 indicates strong energy transfer efficiency. The results suggest that the cold ablation process is effective in fabricating high-frequency piezocomposites with improved structural variability.

The study concludes that the cold ablation process is suitable for fabricating high-frequency 1-3 piezocomposites with hexagonal pillars. The hexagonal pillar design offers better performance compared to conventional shapes like square. The fabricated transducer achieved a resonance frequency of 51.2 MHz and a coupling coefficient of 0.69. The cold ablation process allows for greater variability in pillar design and distribution. The structural size of the piezocomposite was smaller than that achieved with traditional methods. The results suggest that the cold ablation process is a viable alternative to the dice-and-fill technique. The study highlights the potential of hexagonal pillars in enhancing transducer performance. The findings indicate that the cold ablation process can be used to develop high-frequency ultrasonic transducers with improved structural flexibility.