| 摘要 |
PURPOSE:To form a drum-shaped hexagonal boron nitride film on a substrate, by bringing a nitrogen compd. and boron compd. at a specific temp. into reaction by a CVD method to deposit the hexagonal boron nitride film on the substrate and removing part of the substrate. CONSTITUTION:The substrate 2 (quartz glass sheet, etc., having about 0.3-2.0mm thickness is disposed in a reaction tube of a CVD device. The nitrogen compd. (NH3, etc.) and the boron compd. [B(CH3O)3, etc.] are introduced with hydrogen gas as a carrier gas into the reaction tube and are brought into reaction at 700-1,700 deg.C to deposit the hexagonal boron nitride film to about 0.5-50mu on the substrate 2. The front and side faces of the film 1 and the peripheral edge of the substrate 2 to be made to remain are coated with wax 3 so as not to contact an etching liquid, then the substrate is immersed into the etching liquid, by which the exposed part of the substrate 2 is removed. Further, the wax 3 is removed to extend the hexagonal boron nitride film 1 on the substrate 2, by which the drum-shaped hexagonal boron nitride film adequate as the mask substrate for X-ray lithography is formed. |
