Ceramic Material Working by UV Light Irradiation in several Atmosphere

本研究提出了紫外光增强表面改性的方法。为了实现这一点，准分子激光束照射到陶瓷材料在一些大气中的气体。结果，在氮化硅陶瓷上出现小的突起。另一方面，随着脉冲次数的增加，氧化铝陶瓷的表面变得更光滑。这一现象可以解释为激光辐照氧化铝产生的水蒸气在氧化铝表面重新聚集，表面变得光滑，水在其网状结构中可以分解气体。因此，水可以被认为是气体的微室。在控制溶解气体浓度的水中，用准分子激光辐照陶瓷。结果表明，通过控制浓度可以改变氧化层的厚度。在高氧分解水中，层变厚。而且该层比非氧化层更容易去除，而且ZnSe在高温下与水反应，对波长大于500nm的光是透明的。然后在纯水中用紫外光（ArF：193nm）照射ZnSe。只有辐照部分与水反应，并且其温和地溶解。处理后的表面变得更光滑。总结出激光辐照可以实现水热处理。该技术可应用于立方氮化硼材料，有望成为一种先进的材料。

In this research, Ultra-violet light enhansed surface modification is proposed. In order to realize this, excimer laser beam was irradiated on to the ceramic materials in some atmospheric gases. As the results, small projection appeared on a silicon nitride ceramic. On the other hand, surface became smoother on alumina ceramics as the number of pulse increased. This phenomena can be explained that vapor from alumina by laser irradiation gathered again on the aluminasurface then surface came smoother.Water can resolve gases in its net structure. There fore water can be recognized as a micro-chamber of gases. Ceramics were irradiated by excimer laser beam in the water of resolved gas concentration controlled. It became clear that the oxidation layr can be changed by controling the concentration. In highly oxygen resolved water, the layr became thicker. And this layr is much easier to remove than non-oxidation layr.By the way ZnSe reacts with water in high temperature and is transparent for the light longer wave length than 500nm. Then UV light (ArF : 193nm) was irradiated on ZnSe in the pure water. Only the irradiated part reacted with water and it solved away gently. The treated surface became smoother. Then it can be summarize that the laser irradiation can realize hydro-thermal processing. This technique will be available to cubic boron nitride which is expected be a advanced material.