Patent ID: 8383296
Filing Date: 2013-02-26
Classification: G03F

Abstract:
1. A method for manufacturing photomasks, comprising at least one step of cleaning the photomask and at least one step of placing a protective pellicle onto the photomask, and further comprising at least one step of removing ammonia and sulfate residue between the cleaning step and the pellicle placement step, the step of removing ammonia and sulphate residue comprising: placing the photomask into a sealed chamber, creating a low pressure within the sealed chamber by pumping out the gases that it contains, exposing the photomask to infrared radiation, with a hashing-based infrared radiation emission control and wherein the photomask is heated at a temperature between 50° C. and 300° C., stopping the infrared radiation, waiting that the temperature of the photomask does not exceed 50° C. before restoring the atmospheric pressure, restoring the atmospheric pressure within the chamber by injecting a clean, non-reactive gas, and removing the photomask from the chamber.