摘要 |
<p>A Mg source 3 is received in a vessel 1 having an opening 8, and the vessel 1 is heated at 670 DEG C or higher to effuse Mg vapor through the opening 8. Since the vessel 1 is filled with Mg vapor, Mg is evaporated from molten state under stable condition without fluctuations in evaporation speed. The Mg vapor is effectively consumed for vapor deposition. A reflector plate may be provided at the outlet of the opening 8, or a duct for introducing Mg vapor from the vessel to the surface of a substrate sheet may be provided. In order to evaporate Mg from stabilized molten state, operational conditions are preferably determined so as to satisfy the relationships of W1/W2 < 0.6 x (PMg/V<3>) and W1/W2 < 0.04 x PMg, wherein W1 represents the area (mm<2>) of the opening 8, W2 represents the evaporation surface area (mm<2>) of the Mg source 3, PMg represents Mg vapor pressure (torr.) and V represents the degree of vacuum. <IMAGE></p> |