Patent Number: 046510095
Section: claims

1. An apparatus wherein a first member bearing a pattern and a second member are placed in close contact facing each other and the second member is exposed to a pattern on the first member with radiation through the first member, said apparatus comprising: means for aligning the first and second members is a predetermined positional relation;  means provided to cooperate with a first surface of the first member facing the second member for defining a first substantially gas-tight chamber;  means provided to cooperate with a second surface of the first member not facing the second member for defining a second substantially gas-tight chamber which is independent of said first gas-tight chamber; and  means for supplying a vacuum to said first and second gas-tight chambers, said vacuum supplying means being operative to maintain said first and second gas-tight chambers substantially at the same vacuum and then operative to reduce the vacuum in said second gas-tight chamber as compared with that in said first gas-tight chamber thereby bringing the first and second members into close contact with each other.  aligning the first and second members in a predetermined positional relation;  supplying a vacuum to a first substantially gas-tight chamber which includes a surface of the first member facing the second member and to a second substantially gas-tight chamber which is defined independently from said first gas-tight chamber which includes another surface of the first member not facing the second member, so that said first and said second gas-tight chambers are maintained substantially at the same vacuum; and  reducing the vacuum in said second gas-tight chamber as compared with that in said first gas-tight chamber to bring the first and second members into close contact with each other. 2. An apparatus according to claim 1, wherein said vacuum supplying means supplies the vacuum to said first and second gas-tight chambers at the same time. 3. An apparatus according to claim 1, wherein said vacuum supplying means is operative to reduce the vacuum in said second chamber to an atmospheric pressure level. 4. An apparatus according to claim 1, wherein said aligning means includes a holder for holding the second member and wherein said apparatus further comprises means provided to cooperate with said holder for defining a third substantially gas-tight chamber which is independent of said first and said second gas-tight chambers. 5. An apparatus according to claim 4, wherein said vacuum supplying means is operative to supply a vacuum to said third gas-tight chamber at the same time as the vacuum supplied to said first and second gas-tight chambers. 6. An apparatus according to claim 1, wherein said first gas-tight chamber defining means has a transmitting portion for allowing passage of the radiation with which the second member is exposed to the pattern of the first member. 7. An apparatus according to claim 6, wherein said aligning means includes a holder for holding the first member and wherein said first gas-tight chamber defining means has an element for elastically forcing the first member to said holder. 8. A method wherein a first member bearing a pattern and a second member are placed in close contact with each other and the second member is exposed to the pattern of the first member with radiation through the first member, said method comprising the steps of: 9. A method according to claim 8, wherein said first and second gas-tight chambers are maintained substantially at the same vacuum while keeping a predetermined gap between the first and second members. 10. A method according to claim 9, wherein the first and second members are brought substantially into contact with each other prior to reducing the vacuum in said second gas-tight chamber.