Pulsed laser melting in liquid for crystalline spherical submicrometer particle fabrication– Mechanism, process control, and applications

Pulsed laser melting in liquid (PLML) has been developed to fabricate crystalline spherical submicrometer particles (SMPs) by irradiating lasers onto raw particles dispersed in liquid. This technique differs from highly energetic pulsed laser ablation in liquid for nanoparticle (NP) fabrication and is based on the photothermal processing of particles dispersed in liquid that is developed from the well-studied NP reshaping of noble metals, such as Au and Ag. However, this phenomenon can be extended beyond Au and Ag using appropriate raw particles and laser fluences for various materials (semiconductors, oxides, carbides, etc.) to reshape or melt agglomerated raw particles. Since well-defined dense and smooth crystalline particles in this size range are difficult to fabricate by other particle fabrication methods, the generated spherical SMPs are useful for realizing miniaturized bulk functionality and submicrometer-specific functionality. This review comprehensively summarizes the historical background, the basic mechanism behind the process, parameters affecting particle size and morphology, possible application examples, specialized issues for characterization and mass production, and future directions of this method. This review will be helpful, especially for those seeking well-defined spherical SMPs with various functionalities.