Wavy micro channels in micropatterned ceramic sheet formed by combined process of laser beam machining and imprinting

Abstract

Micro channels made of polymers are commonly used for MEMS and μTAS (micro-total analysis system) devices. In this research, we developed a process for fabricating a ceramic sheet with micro channels. The developed process is based on powder metallurgy process. A compound material, a mixture of ceramic powder and polymer, was prepared as sheet material. We employed laser machining to machine the sacrificial layer to form micro channels inside the sheet. We also employed imprinting, which is a process of pressing with a mould while heating, to form a structure with surface patterns and micro channels curving along with it. After the imprinted sheet was debound and sintered by heating, a ceramic sheet with micro-surface patterns and micro channels was obtained. As ceramics have high heat durability and low chemical reactivity, ceramic micro channels can be used for flow sensors or chemical reaction testers operated in harsh environments, such as high temperature or mechanical parts operated with reactive chemicals. In addition, by imprinting wavy patterns, the surface area can be increased. Therefore high efficiency heat exchangers can be built. Moreover, this method can be applied on SOFCs (solid oxide fuel cell) by fabricating YSZ (yttria stabilized zirconia) micro channels.