Tadahiko Takigawa

200-mm EPL stencil mask fabrication and metrology

200-mm electron-beam projection lithography (EPL) masks were fabricated starting from stress-controlled silicon-on-insulator (SOI) substrates. The internal stress of the SOI layer is controlled to be ca. 10 MPa by B doping. The blank fabrication process has been established by the Bosch deep trench etch process. EB patterning was done on a JEOL JBX9000MVII with a positive-tone chemically amplified resist of 400-nm thickness. Resist image of 200-nm wide lines-and-spaces pattern was transferred to 2-um thick SOI layer by a shallow trench etching. A dual-mode critical dimension (CD)-SEM was implemented, and used for mask characterization. Preliminary results on uniformity of CD-shift in the dry etching and final CD were reported. 200-mm EPL masks with a gate layer of a system-on-chip device pattern were fabricated.