| 摘要 |
PURPOSE:To form a BN film for X-ray lithography mask excellent in characteristics, such as water resistance and moisture resistance, by adding specific amounts of SiF4 at the time of forming a BN film by a plasma chemical vapor deposition method by using a gaseous mixture of B2H6 and NH3. CONSTITUTION:After the pressure in a reaction vessel is reduced, a high-frequency voltage is applied to an electrode inside the reaction vessel while allowing a gaseous mixture of B2H6 and NH3 to flow to produce plasma and allow the gaseous mixture to react, by which a BN film is formed on the surface of a substrate in the vessel. At this time, the flow-rate ratio between NH3 and B2H6 is regulated to >=0.5, SiF4 is added by about 30% flow rate based on that of B2H6, and the reaction pressure of the gaseous mixture is regulated to 1-5torr, and further, the BN film vapor deposition substrate is previously heated to 200-500 deg.C. By this method, the BN film for X-ray lithography mask excellent in water resistance, moisture resistance, and tensile strength can be formed on the substrate. |
