Chemical vapor deposition of ordered structures in YAG-alumina eutectic system

The eutectic structure of metals and ceramics is the result of a self-organization phenomenon in which multiple solid phases solidify with an ordered structure from a liquid phase. Hence, a melt-solidification process was the only way to generate ordered structures in a ceramic eutectic system. Here, we prepared ordered structures of Y3Al5O12 (YAG)-Al2O3 composites via chemical vapor deposition in the YAG-Al2O3 eutectic system. Spatially periodic YAG rod and lamellar structures were generated in an alumina matrix homoepitaxially grown on the sapphire substrates on the Al2O3-rich side of the eutectic composition, whereas alpha-Al2O3 rod and lamellar structures were generated in a YAG matrix on the Y2O3-rich side. The results reveal that the pattern formation of ordered structures in a ceramic eutectic system can occur not only during in the melt-solidification process but also during the vapor deposition process. The Ce3+-doped YAG-Al2O3 composite film converts some of the blue light into yellow light, allowing some of it to pass through, and emitting white light. The Eu3+-doped YAG-Al2O3 composite film can be utilized as a scintillation screen for a high-resolution X-ray imaging test to see though a semiconductor storage device.