Patent ID: 8091863

Claim:
A gate valve of a semiconductor manufacturing apparatus, which is arranged between a processing chamber in which processing is performed and a transfer chamber which carries a substrate on which the processing is performed, the gate valve comprising: a first gate valve at a side of the processing chamber which opens and closes an opening of the processing chamber, the first gate valve including a first valve body and a first valve box, the first valve box including a first opening facing the opening of the processing chamber; a first sealing member which is attached to the first valve body of the first gate valve and seals a clearance between the first opening and the first valve body; a second gate valve at the side of the transfer chamber which opens and closes an opening of the transfer chamber, the second gate valve including a second valve body and a second valve box, the second valve box including a second opening facing the opening of the transfer chamber; and a second sealing member which is attached to a second valve body of the second gate valve and seals a clearance between the second opening and the second valve body, wherein the first and second gate valves are attached to each other such a manner that the substrate can be transferred from the transfer chamber into the processing chamber or vice versa through the first and second openings, and a thermal insulator is inserted between the first and second gate valves to suppress heat transfer from the first gate valve to the second gate valve, and wherein the first sealing member is formed of a first material and the second sealing member is formed of a second material having material properties different from the first material in terms of vacuum sealability and resistance to an atmosphere of the processing chamber.