Method for cleaning laser film

Abstract

The invention relates to a method for cleaning a laser film. The method specifically comprises the steps that a cotton swab dipped with acetone is used for slightly wiping the surface of the laser film, the wiped laser film is put in a first cleaning tank, alkaline solution is filled into the first cleaning tank to clean a sample, and the solution temperature is the room temperature; the volume ratio of the alkaline solution is that NH4OH: H2O2: H2O equals to 1: 10: 50; the obtained solution is respectively subjected to ultrasound for 2-4 minutes at the frequencies of 120 kilohertz-180 kilohertz and 200 kilohertz-300 kilohertz; the obtained sample is put in a second cleaning tank and is rinsed through deionized water, and the temperature of the deionized water is the room temperature; the sample is put in a third cleaning tank 3, the deionized water is added into the third cleaning tank, and the sample is respectively subjected to ultrasound for 3-6 minutes at the frequencies of 120 kilohertz-180 kilohertz and 200 kilohertz-300 kilohertz; and the sample is taken out, repeatedly cleaned and dried to obtains the required product. The method has the advantages that the high cleaning efficiency is realized, organic pollutants and contamination particles on the surface are effectively removed, meanwhile, the laser film cannot be physically damaged, the film is prevented from being eroded and damaged due to the particles which are absorbed to the surface of the film when the film is used in a high-power laser system, and the laser film is enabled to have high damage threshold when being used in the high-power laser system.

Description

technical field [0001] The invention relates to a cleaning method combining alkaline solution and ultrasonic waves, in particular to a high-efficiency cleaning method for the surface of a laser thin film with a high damage threshold. Background technique [0002] Laser thin films are key components in high-power laser systems and one of the key factors to achieve the optical performance of the system. Thin film is also the most vulnerable link in the laser system. Film damage not only reduces the output quality of the laser, but also causes distortion of the beam front and phase, and the modulation of the laser beam can easily cause damage to other optical components in the system, thus causing damage to the entire optical system. The system brings catastrophic damage. Therefore, with the expansion of high-power lasers and their application range, the laser damage of thin films has become an important factor affecting the stability and service life of various laser systems,...

AI Technical Summary

Problems solved by technology

Among them, the wiping method is more effective for large-scale particles above microns, but it is difficult to remove sub-micron particles; RCA cleaning belongs to chemical cleaning, which can reduce the adsorption force between particles and films, but if the concentration of chemical solutions is not properly controlled, it will cause Severe corrosion of the film increases the surface roughness of the film, increases the light loss caused by the light scattering of the film, and changes the spectral characteristics; ultrasonic cleaning can efficiently remove various scales from micron to submicron on the surface of the substrate through the selection of frequency. However, when the ultrasonic frequency is selected improperly or the ultrasonic time is too long, it will cause physical damage such as film shedding

Therefore, for the selection of optical thin film cleaning process, we should not only pay attention to the cleaning efficiency of pollutants, but also avoid damage to the film during the cleaning process. However, there are no relevant reports on the effective cleaning method of laser thin film at home and abroad.

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