Method of Keeping a Proximity Printing Mask at a Constant Temperature
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-07
A mask used for proximity printing with corpuscular beams and X-rays is kept at a constant temperature by being exposed to a heat source at times when no beam or ray is incident. The temperature of an irradiated mask increases until a thermal equilibrium has been reached and returns to the ambient value after the beam or ray has been switched off. This is illustrated in the diagram, the solid curve referring to a mask that has been radiated twice, with the temperature being plotted versus time. For a mask intermittently exposed to a heat source, e.g., a beam of infrared light, a T/t curve (dashed line in the diagram) is obtained which is identical with the solid curve in areas where there are temperature changes, provided that the heat is suitably adjusted to the radiation energy.