Investigation on ultimate results and formation mechanism of the micro-nano particles removal by laser plasma

Abstract

Micro/nanoparticles contamination is one of the key factors affecting the quality of precision manufacturing, and the traditional cleaning methods cannot function effectively. The laser plasma has high temperature and pressure, which can be used as a new and potential method to implement the removal of micro/nanoparticle, and it has become the focus of attention. This paper aims to analyze the particles removal process under the action of repetitively pulsed laser plasma, which is mainly composed of the changes in particle morphologies, the ultimate removal results, as well as the corresponding academic analysis based on the thermodynamic effects. Investigation results show that the particles removal characteristics depend heavily on the number of pulsed plasma, micrometer-size particles can be removed at the beginning, and then particles with the size about several hundred nanometers in the following stages. Analyzed from the morphological properties of particles, the refinement can be found, more specifically, the particle can be broken up into more smaller ones under the action of laser plasma with high pressure and temperature. The particles refinement will deepen the difficulty on removal efficiency, and when the particles ultimately convert into ultrasmall nanoparticles with several nanometers, which will attach to substrate presenting as flocculent aggregate, and cannot be completely wiped out.

The spatial phase transition of micro/nano particles and its effect on the cleaning efficiency of laser-plasma shock wave cleaning

“…Cetinkaya 7 noted that such particles can be removed at high temperatures due to thermodynamic effects. In 2020, Luo 8 proposed that particles would melt and break under the action of thermodynamics. In 2021, Lai 9 also studied the damage of particles to the base and proposed that particles would increase the damage to the base.…”

Femtosecond laser interferometry of microsized absorptive plasma

“…The investigation of laser plasma produced as a result of ionization of the transparent medium by intense (>10 12 W cm −2 ) laser pulses is an important direction in the physics of radiation interaction with condensed matter. A large number of works devoted to the study of these phenomena are aimed at understanding the mechanisms of formation and dynamics of a non-equilibrium, inhomogeneous plasma, controlling its physical properties, and development of new plasma-assisted technologies [1][2][3][4][5][6][7][8][9][10]. Of particular interest are the novel laser technologies utilizing such plasmas for micro-and nanosized modification of condensed matter: nanolithography [11,12], surface and bulk structuring of solids [13][14][15], nanocavitation of liquids, and nanosurgery of bioobjects [16,17].…”