Patent Number: 
Section: claims

1. An exposure apparatus, comprising: an exposure system for executing an exposure operation by use of an exposure beam to transfer a pattern of a mask onto a substrate, the mask having a photocatalyst portion;  an auxiliary space for irradiating therewithin, the mask with an auxiliary radiation different from the exposure beam, to accelerate a photocatalytic reaction of the photocatalyst portion; and  humidity control means for controlling humidity inside said auxiliary space. 2. An apparatus according to  claim 1 , further comprising an exposure space for executing the exposure operation therewithin. claim 1 3. A method according to  claim 1 , further comprising a mask storing space for keeping therein the mask during a non-exposure period. claim 1 4. An apparatus according to  claim 3 , wherein said mask storing space is different from said auxiliary space, and wherein said apparatus further comprises an exposure space, an auxiliary light source for irradiating the mask kept in said auxiliary space, and second control means for controlling humidity of said mask storing space independently of said exposure space. claim 3 5. An apparatus according to  claim 3 , wherein said mask storing space functions also as said auxiliary space, and wherein said apparatus further comprises an exposure space, an auxiliary light source for irradiating the mask kept in said mask storing space, and second control means for controlling humidity of said mask storing space independently of said exposure space. claim 3 6. An apparatus according to  claim 2 , wherein said exposure space functions as said auxiliary space, and wherein said apparatus further comprises an auxiliary light source for irradiating the mask kept in said exposure space. claim 2 7. An apparatus according to  claim 2 , wherein said exposure space and said auxiliary space are separated from each other by one of a wall and a differential exhausting system. claim 2 8. An apparatus according to  claim 1 , wherein said humidity control means controls the humidity in said auxiliary space in a range of 1-90%. claim 1 9. An apparatus according to  claim 1 , wherein said humidity control means controls the humidity in said auxiliary space in a range of 4-80%. claim 1 10. An apparatus according to  claim 1 , wherein the auxiliary radiation comprises one of an ultraviolet ray, an extreme ultraviolet ray and an X-ray. claim 1 11. An apparatus according to  claim 1 , wherein the exposure beam comprises one of an extreme ultraviolet ray and an X-ray. claim 1 12. An apparatus according to  claim 1 , wherein the mask has the photocatalyst portion doped with metal. claim 1 13. An apparatus according to  claim 12 , wherein the metal is one of Cr and V. claim 12 14. An apparatus according to  claim 1 , further comprising an exhaust port communicated with said auxiliary space. claim 1 15. An apparatus according to  claim 1 , wherein the mask comprises one of a transparent type mask and a refractive type mask. claim 1 16. A device manufacturing method, comprising the steps of: executing an exposure operation by use of an exposure beam to transfer a pattern of a mask onto a substrate, the mask having a photocatalyst portion;  irradiating, in an auxiliary space, the mask with an auxiliary radiation different from the exposure beam to accelerate photocatalytic reaction of the photocatalyst portion; and  controlling the humidity inside the auxiliary space. 17. A method according to  claim 16 , wherein the humidity in the auxiliary space is controlled in a range of 1-90%. claim 16 18. A method according to  claim 16 , wherein the humidity in the auxiliary space is controlled in a range of 4-80%. claim 16 19. A method according to  claim 16 , wherein the auxiliary radiation comprises one of an ultraviolet ray, an extreme ultraviolet ray and an X-ray. claim 16 20. A method according to  claim 16 , wherein the exposure beam comprises one of an extreme ultraviolet ray and an X-ray. claim 16 21. A method according to  claim 16 , further comprising exhausting an inside gas of the auxiliary space. claim 16 22. A method according to  claim 16 , further comprising conveying the mask from an exposure space into the auxiliary space for the irradiation of the same with the auxiliary radiation when contamination of the mask reaches a predetermined level. claim 16 23. A method according to  claim 16 , further comprising conveying the mask from an exposure space into said auxiliary space for irradiation of the same with the auxiliary radiation when a transmittancy of the mask is reduced. claim 16 24. A method according to  claim 16 , wherein the mask comprises one of a transparent type mask and a refractive type mask. claim 16 25. A method according to  claim 16 , further comprising producing a semiconductor device by use of the exposed substrate. claim 16