Device for producing extreme UV radiation
An extreme UV radiation producing device in which adhesion of solid tin in the vacuum pump of an evacuation device is restricted, so that the maintenance period and the replacement period of the pump is prolonged is achieved by the provision of a treatment unit between a radiation source chamber and the evacuation device. The treatment device has a hydrogen radical producing part in which tin and/or a tin compound in the evacuated gas from the radiation source chamber is/are made into a tin hydride; and a heat treatment part in which the tin hydride is thermally decomposed and in which the tin produced liquefied and separated from the evacuated gas. The liquid tin is fed into a collecting/storage vessel and the evacuated gas from which the tin and/or a tin compound has been removed fed to the evacuation device.
1. Device for producing extreme UV radiation, comprising:
a vessel for producing a high density and high temperature plasma;
a raw material supply means for supplying a raw material which contains at least one of tin and a tin compound in order to feed as a species for extreme UV radiation into the vessel;
a means for heating and excitation which heats and excites the raw material which has been delivered to the vessel and which produces a high density and high temperature plasma;
an evacuation device which is connected to the vessel;
an extreme UV radiation exit part which extracts extreme UV radiation which is emitted from the high density and high temperature plasma; and
a treatment unit between the vessel and the evacuation device, the treatment unit having means for separating at least one of tin and a tin compound from a evacuated gas which is released from the vessel and which contains at least one of tin and a tin compound.
2. Device for producing extreme UV radiation as claimed in claim 1 , wherein the treatment unit has a collecting-storage vessel for capturing the separated at least one of tin and a tin compound.
3. Device for producing extreme UV radiation as claimed in claim 1 , further comprising means for supplying the evacuated gas from which the at least one of tin and a tin compound has essentially been removed to the evacuation device.
4. Device for producing extreme UV radiation as claimed in claim 1 , wherein the treatment unit contains a hydrogen radical treatment part for producing hydrogen radicals that react with the evacuated gas which contains at least one of tin and at in compound for converting the at least one of tin and a tin compound which is contained in the evacuated gas into tin hydride.
5. Device for producing extreme UV radiation as claimed in claim 4 , wherein, downstream of the hydrogen radical treatment part, there is a heating means for heating the evacuated gas which contains tin hydride and which is released from the hydrogen radical treatment part to at least the temperature at which tin is liquefied, thermally decomposing tin hydride to the tin, converting the tin produced by decomposition into liquid tin and separating it from the evacuated gas.
6. Device for producing extreme UV radiation as claimed in claim 4 , wherein downstream of the hydrogen radical treatment part,
there is a cooling means for cooling the discharge gas which contains tin hydride and which is released from the hydrogen radical treatment part to at most the temperature at which the tin hydride is liquefied, converting the tin hydride to the liquid tin hydride and separating the liquid tin hydride from the evacuated gas.