Laser pulse sequence silicon hole processing system with adjustable sub-pulse time interval

Abstract

The invention discloses a laser pulse sequence silicon hole processing system with an adjustable sub-pulse time interval. The laser pulse sequence silicon hole processing system is characterized in that a silicon hole processing system consisting of a Fabry-Perot cavity, a light source input unit, a sample processing unit and a coaxial monitoring unit is adopted to generate a pulse sequence with a continuously adjustable sub-pulse time interval in a range of 1-3500 ps, and silicon hole processing for realizing secondary ablation of ejected substances can be realized; the light source input unit is composed of a laser and a light path formed by connecting a circular gradually-changing neutral optical filter, a polarization beam splitting cube and a quarter-wave plate; the sample processing unit consists of a light path connected to a reflecting mirror and an objective lens and a three-dimensional translation table; and the coaxial monitoring unit is composed of a beam splitter, a light path connected to a white light source and a CCD camera. Compared with the prior art, the system has the advantages that the time for subsequent sub-pulses to reach the surface of a sample is accurately controlled, secondary ablation of ejected substances is achieved, accumulation of remelting substances around holes is reduced, and the processing quality is improved.

Description

technical field [0001] The invention relates to the technical field of ultrafast laser processing, in particular to a silicon hole processing system with adjustable sub-pulse time interval laser pulse sequences. Background technique [0002] The femtosecond laser is famous for its ultra-fast and super-powerful features. It has the advantages of high resolution, small thermal effect, and high flexibility. It can meet the needs of high-quality and high-precision processing in industry. The rapid development of laser processing and manufacturing technology has led to its irreplaceable advantages in laser drilling, laser surface modification, laser additive manufacturing, laser welding, and laser cutting. The femtosecond laser with lower pulse energy can meet the industrial requirements in processing quality, but the corresponding low processing efficiency greatly limits its application in production. When using a high-energy femtosecond laser with an energy flux density far ex...

AI Technical Summary

Problems solved by technology

Femtosecond lasers with lower pulse energy can meet industrial requirements in terms of processing quality, but the corresponding low processing efficiency greatly limits their application in production

When using a high-energy femtosecond laser with an energy flux density far exceeding the ablation threshold, although the processing efficiency is improved, at the same time, the heat-affected zone caused by the laser is enlarged, the remelted material is increased, and the deposition of ablation ejecta is harmful to the substrate. The damage and contamination of the chip, the accuracy and flatness of the ablation are significantly reduced

[0003] The quality of high-energy femtosecond laser processing in the existing technology cannot be guaranteed, and the decline in processing quality leads to a series of important application problems. For example, the performance and life of core components in the manufacturing industry will be affected. The chemical reaction kinetics cannot be precisely controlled, safety and efficiency are difficult to guarantee, and normal tissues and skin around the ablation site in the medical beauty industry are easily "accidentally injured", etc.

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