Provided is a high purity tin (Sn) having an extremely low oxygen content. A high purity tin having a tin purity of 5N (99.999% by mass, provided that carbon, nitrogen, oxygen and hydrogen are excluded) or more, wherein the high purity tin has an oxygen content of less than 10 ppb by mass, as measured by elemental analysis using Dynamic-SIMS.

Provided is high purity tin having purity of 5N (99.999% by mass), which can suppress generation of particles. According to the high purity tin, the number of particles each having a particle diameter of 0.5 μm or more is 50,000 or less per a gram.

Provided is high purity tin having purity of 5N (99.999% by mass), which can suppress generation of particles. According to the high purity tin, the number of particles each having a particle diameter of 0.5 μm or more is 50,000 or less per a gram.

Any metal having a low -ray emission, the metal being any one of tin, silver, copper, zinc, or indium, wherein an emission of an -ray after heating the metal at 100 C. in an atmosphere for six hours is 0.002 cph/cm.sup.2 or less. Any metal of tin, silver, copper, zinc and indium each including lead as an impurity is dissolved to prepare a hydrosulfate aqueous solution of the metal and lead sulfate is precipitated and removed in the solution. The lead sulfate is precipitated in the hydrosulfate aqueous solution by adding a lead nitrate aqueous solution including lead having an a-ray emission of 10 cph/cm.sup.2 or less to the hydrosulfate aqueous solution, from which the lead sulfate has been removed, and, at the same time, the solution is circulated while removing the lead sulfate to electrowinning the metal using the hydrosulfate aqueous solution as an electrolytic solution.

Any metal having a low -ray emission, the metal being any one of tin, silver, copper, zinc, or indium, wherein an emission of an -ray after heating the metal at 100 C. in an atmosphere for six hours is 0.002 cph/cm.sup.2 or less. Any metal of tin, silver, copper, zinc and indium each including lead as an impurity is dissolved to prepare a hydrosulfate aqueous solution of the metal and lead sulfate is precipitated and removed in the solution. The lead sulfate is precipitated in the hydrosulfate aqueous solution by adding a lead nitrate aqueous solution including lead having an a-ray emission of 10 cph/cm.sup.2 or less to the hydrosulfate aqueous solution, from which the lead sulfate has been removed, and, at the same time, the solution is circulated while removing the lead sulfate to electrowinning the metal using the hydrosulfate aqueous solution as an electrolytic solution.

A deoxidation system for purifying target material for an EUV light source includes a furnace having a central region and a heater for heating the central region in a uniform manner. A vessel is inserted in the central region of the furnace, and a crucible is disposed within the vessel. A closure device covers an open end of the vessel to form a seal having vacuum and pressure capability. The system also includes a gas input tube, a gas exhaust tube, and a vacuum port. A gas supply network is coupled in flow communication with an end of the gas input tube and a gas supply network is coupled in flow communication with an end of the gas exhaust tube. A vacuum network is coupled in flow communication with one end of the vacuum port. A method and apparatus for purifying target material also are described.

Provided is a high purity tin (Sn) having an extremely low oxygen content. A high purity tin having a tin purity of 5N (99.999% by mass, provided that carbon, nitrogen, oxygen and hydrogen are excluded) or more, wherein the high purity tin has an oxygen content of less than 10 ppb by mass, as measured by elemental analysis using Dynamic-SIMS.

Provided is a high purity tin (Sn) having an extremely low oxygen content. A high purity tin having a tin purity of 5N (99.999% by mass, provided that carbon, nitrogen, oxygen and hydrogen are excluded) or more, wherein the high purity tin has an oxygen content of less than 10 ppb by mass, as measured by elemental analysis using Dynamic-SIMS.

A deoxidation system for purifying target material for an EUV light source includes a furnace having a central region and a heater for heating the central region in a uniform manner. A vessel is inserted in the central region of the furnace, and a crucible is disposed within the vessel. A closure device covers an open end of the vessel to form a seal having vacuum and pressure capability. The system also includes a gas input tube, a gas exhaust tube, and a vacuum port. A gas supply network is coupled in flow communication with an end of the gas input tube and a gas supply network is coupled in flow communication with an end of the gas exhaust tube. A vacuum network is coupled in flow communication with one end of the vacuum port. A method and apparatus for purifying target material also are described.

A deoxidation system for purifying target material for an EUV light source includes a furnace having a central region and a heater for heating the central region in a uniform manner. A vessel is inserted in the central region of the furnace, and a crucible is disposed within the vessel. A closure device covers an open end of the vessel to form a seal having vacuum and pressure capability. The system also includes a gas input tube, a gas exhaust tube, and a vacuum port. A gas supply network is coupled in flow communication with an end of the gas input tube and a gas supply network is coupled in flow communication with an end of the gas exhaust tube. A vacuum network is coupled in flow communication with one end of the vacuum port. A method and apparatus for purifying target material also are described.