Method for cleaning micro-nano particles through shock waves induced by spatially constrained double-beam laser

Abstract

A method for cleaning micro-nano particles through shock waves induced by spatially constrained double-beam laser comprises the following steps that (1), a to-be-cleaned substrate is bonded to a three-dimensional moving platform, and the three-dimensional moving platform is moved to enable the to-be-cleaned substrate to be located at a laser pulse focus point and a cavity outlet; and (2), a first pulse laser beam and a second pulse laser beam are focused in a cavity to induce gas breakdown to generate plasma shock waves, the strength of the shock waves is enhanced through reflection of the inner surface of the cavity, and the micro-nano particle pollutants on the surface of the to-be-cleaned substrate fly away from the surface of the to-be-cleaned substrate under the action of shock wave removal force. The method for cleaning the micro-nano particles through the shock waves induced by the spatially constrained double-beam laser can effectively increase the cleaning area of the surface of a substrate and improve the cleaning efficiency.

Description

technical field [0001] The invention relates to surface cleaning technology, in particular to a method for cleaning micro-nano particles with space-constrained double-beam laser-induced shock waves. Background technique [0002] As the size of chip units continues to shrink (DRAM half-pitch is expected to reach 14nm in 2021), the size of contamination particles on the surface of silicon wafers to be cleaned has been smaller than 10nm. Particulate pollutants will reduce the performance of integrated chips, micro-machines, precision optical components and other products in the IC industry, and in severe cases will lead to product failure. Traditional mechanical cleaning and chemical cleaning methods (mechanical scrubbing, chemical solution immersion, ultrasonic cleaning, etc.) have the disadvantages of destroying the substrate and secondary pollution, and these methods have low cleaning efficiency for particles with a diameter of less than 100nm. [0003] Laser-induced plasma...

AI Technical Summary

Problems solved by technology

Recent studies have found that double-pulse induced plasma cleaning technology can effectively suppress the formation of uncleaned blind areas in single-pulse laser-induced plasma shock wave cleaning, but it does not solve the problem of small cleaning areas

Invention patent 200810165891.0 "Method and device for cleaning substrates" proposes a laser-induced shock wave cleaning method with inner chamber constraints, which has the disadvantages of small cleaning area and low cleaning efficiency

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