Microfabrication techniques for thick structure of metals and PZT

Micro fabrication techniques for thick structure are developed. One method is a micro fabrication method using injection molding. And another method is the coating method using hydro gel. First method is almost same technique which is named MIM or CIM. In the process, the powder is mixed with the binder and mixture is injection molded. The molded parts are extracted the binder using supercritical carbon dioxide, and sintered. Employing this process, micro pattern which has aspect ratio more than 5 can be molded by metal powder and PZT. In this method, a micro pattern made by laser ablation is used as a die. As compared with other micro fabrication techniques, this method can utilize the molding die repeatedly. Consequently, the producing cost of micro parts can be decreased by this method on actual production process. Second method is a technique which uses the PVA hydro gel. The powder is mixed with water which contains the PVA from 3 to 15%. The mixed compound is sandwiched with PE films. It is froze and a gel sheet which has thickness from 40 to 100 μm is obtained. Using the sheet, the ceramic and metal are coated on the Silicon wafer, and thick structure is fabricated.