| 摘要 |
<p>PURPOSE: To maintain the uniformity of the thickness of phase transition films by etching 80 to 90% of the entire etching quantity by dry process etching and remaining 20 to 10% by wet process etching at the time of etching the phase transition films. CONSTITUTION: The phase transition mask is produced by successively depositing the phase transition film 22 and light shielding film 23 on a quartz layer 21, etching part of this light shielding film 23, patterning a photoresist and etching part of the phase transition film 22, i.e., 80 to 90% of the entire etching quantity by the dry process etching method and the remaining 20 to 10% by the wet process etching method. Namely, the phase transition film 22 is partly etched by the dry process etching method and thereafter, the remaining parts R are further etched by the wet process etching. The dry process etching is executed by anisotropic etching and the wet process etching by isotropic etching using an etching agent HF and HF4 +CH3 COOH.</p> |
