Fabrication Techniques for Multilayer Metalization and Patterning, and Surface Mounting of Components on Cylindrical Substrates for Tube-Shaped Micro-Tools

This paper reports fabrication techniques for multilayer microstructures and surface mounting of small components on cylindrical substrates for tube-shaped high-performance micro-tools. A cylindrical shape is an ideal shape for micro medical tools inserted temporarily or implanted in the human body. Miniaturization, multifunctional capabilities, and high-performance are required for these tools. Tubular lumens, which are useful for the insertion of medical tools and for the injection of drugs, are necessary for endoscopes and catheters. Micro-fabrication on cylindrical substrates meets these demands. Multilayer metallization and patterning, as well as three-dimensional resist patterning have been performed using maskless lithography techniques on glass tubes with 2 and 3 mm outer diameters. Using laser soldering techniques, a high-speed OP amp has been mounted on a multilayer circuit formed on a glass tube to amplify small signals from micro medical sensors. These techniques will realize multifunctional and high-performance tube-shaped micro medical tools with small diameters