Extreme ultraviolet light source and extreme ultraviolet light source target

An extreme ultraviolet light source comprising:

• a hopper having an outlet from which frost can be discharged;
• a freezing machine for cooling the hopper;
• a heater which can heat a wall of the hopper intermittently;
• and
• a vacuum chamber for keeping around the hopper in a vacuum state and having a first window for guiding a laser beam from the outside to the vicinity of the outlet, and a second window for taking out extreme ultraviolet light.

A method of manufacturing an extreme ultraviolet light source target, characterized in that a density of the heavy-metal oxide of the target is made to be 0.5% to 80% of a crystal density of a heavy-metal oxide,

• with a process comprising:
• a step of manufacturing a gel containing a heavy-metal oxide by solving a heavy-metal chloride in dehydrated alcohol and mixing this with water;
• and
• a step of drying the gel.

A method of manufacturing an extreme ultraviolet light source target, characterized in that a density of the heavy-metal oxide of the target is made to be 0.5% to 80% of a density of a heavy-metal oxide crystal

• with a process comprising:
• a step of manufacturing a gel containing a heavy-metal oxide by solving a heavy-metal chloride in dehydrated alcohol and mixing this with water;
• and
• a step of forming a target by mixing the gel with nanoparticles of polystyrene and heating the gel to a temperature which is 240° C. or more but below a decomposition temperature of the heavy-metal oxide.