Sub-nanosecond Lasers Applied to Micromachining of Hard And Brittle Materials

Non-metallic hard and brittle materials include a variety of gemstones, glass, silicon crystals, quartz crystals, ceramics, rare earth magnetic materials, etc. Most of these materials are non-conductors or semiconductors, and they are usually characterized by high hardness, brittleness, abrasion resistance, corrosion resistance, oxidation resistance, and high temperature resistance. As non-metallic hard and brittle materials have many metal materials are difficult to compare the excellent characteristics of its scope of application has been gradually expanded from the traditional construction industry, crafts manufacturing industry to aerospace, machinery, automotive, electronics, chemical industry and other fields. Non-metallic hard and brittle materials and the continuous broadening of the field of application of its processing of low efficiency, high cost of the contradiction is increasingly prominent, resulting in the current traditional processing methods can not adapt to the needs of many industries. Laser energy density of up to 108 ~ 1010W/cm2, direct action on the local surface of non-metallic hard and brittle materials, resulting in instantaneous energy generated by the high temperature melting material or directly destroy the molecular bond of the material. Compared with the traditional processing methods, the efficiency of 8 to 20 times, saving 20% to 30% of the material, can greatly reduce production costs, improve processing accuracy and product quality, but also has the ability to shorten the production cycle, selective processing and precision machining and other advantages.

Traditional hard and brittle materials processing laser used for nanosecond lasers, pulse width is generally more than 5ns, huge volume, high environmental requirements, poor stability, and thermal effects, for many materials processing effect is not ideal. In addition, picosecond and femtosecond lasers have better performance in micromachining, but they are expensive and bulky.

High-power, high-frequency sub-nanosecond lasers are a class of cost-effective quasi-ultrafast lasers, combining the processing accuracy of picosecond lasers and the price advantage of ordinary nanosecond lasers, which have a broad application prospect in the field of precision micromachining, and are favored by industrial customers.

Principle Introduction
Micromachining of hard and brittle materials usually consists of laser, CCD camera, laser collimation and focusing and imaging optical system, galvanometer control system or multi-dimensional mobile rotary platform, input/output control module, computer and control software. Utilizing the high-energy characteristics of laser, through the interaction of photons and materials to achieve the material marking, punching, scribing, cutting, internal carving and other processing; because of its high efficiency, high precision, non-contact and other advantages, it is widely used in microelectronics, micro-mechanical and micro-optical processing and other fields.

Application Market
Hard and brittle materials can be broadly divided into: semiconductor material micromachining, ceramic material micromachining, diamond and gemstone marking and scribing, transparent material micromachining (tempered glass, sapphire glass, etc.), thin-film material ablation, transparent conductive oxides and dielectric ablation, and so on.