| 摘要 |
PURPOSE: A method for preparing stencil mask is provided, to reduce the dimness of beam due to the coulomb repulsive force generated in photo print or mask preparation using an electron beam, thereby improving the resolution. CONSTITUTION: The method comprises the steps of patterning on a SOI wafer by using photo resist; etching it by the depth capable of blocking the incident electron selectively; coating Si3N4 with a pattern protection layer and back window patterning on the rear side of a wafer by using photo resist; etching Si3N4/Si/SiO2 of the rear side and removing a Si3N4 layer; coating platinum for preventing the electron charging; coating W/TiN/Ti on a silicon wafer by evaporation and deposition; patterning on the wafer by using photo resist and etching it; coating a Si3N4 layer with a pattern protection layer and back window patterning on the rear side of a wafer by using photo resist; etching Si3N4/Si of the rear side and removing a Si3N4 layer; and adhering two masks to the wafer by using silver paste. The size of mask is determined to reduce the dimness of beam with minimizing the energy loss of incident electrons; the mask is made of Au, W, Pt or Pd; and the thickness of the mask is 500-3,000 Angstrom. |
