Substrate processing system and substrate transfer apparatus and method

1. A substrate processing system comprising:

a first substrate processing chamber;

a first substrate transfer chamber connected to the first substrate processing chamber;

a second substrate processing chamber;

a second substrate transfer chamber connected to the second substrate processing chamber; and

a buffer chamber connected between the first substrate transfer chamber and the second substrate transfer chamber, the buffer chamber having at least one substrate holder,

wherein at least a part of the buffer chamber and at least one of the first substrate transfer chamber or the second substrate transfer chamber are overlapped with each other when viewed from a top of the substrate processing system,

wherein the first substrate transfer chamber has a first transfer port communicable with the first substrate processing chamber and a stepped side portion, a lower portion of the stepped side portion protruding more toward the buffer chamber than an upper side of the stepped side portion to form a rectangular protruding part, wherein the rectangular protruding part is entirely overlapped with at least the part of the buffer chamber when viewed from the top,

wherein at least a part of the first transfer port and the rectangular protruding part are overlapped with each other when viewed from a side of the substrate processing system,

wherein the first transfer port is not overlapped with the buffer chamber, when viewed from the side of the substrate processing system, and

wherein an upper surface of the buffer chamber, an upper surface of the first substrate transfer chamber, and an upper surface of the second substrate transfer chamber form the same plane.

2. The substrate processing system of claim 1 , wherein the first substrate transfer chamber has a first substrate transfer robot configured to transfer a substrate,

the first substrate transfer robot is movable between a first height and a second height different from the first height, and

the first substrate transfer robot is configured to transfer a substrate between the first substrate transfer chamber and the first substrate processing chamber at the first height and to transfer a substrate between the first substrate transfer chamber and the buffer chamber at the second height.

3. The substrate processing system of claim 2 , wherein the second substrate transfer chamber has a second substrate transfer robot configured to transfer a substrate,

the second substrate transfer robot is movable between the first height and the second height, and

the second substrate transfer robot is configured to transfer a substrate between the second substrate transfer chamber and the second substrate processing chamber at the first height and to transfer a substrate between the second substrate transfer chamber and the buffer chamber at the second height.

4. The substrate processing system of claim 3 , wherein

the second substrate transfer chamber has a second transfer port communicable with the second substrate processing chamber, and

at least the part of the buffer chamber is disposed above at least one of the first transfer port or the second transfer port when viewed from the side.

5. The substrate processing system of claim 4 , wherein the second height is higher than the first height.

6. The substrate processing system of claim 2 , wherein

the second substrate transfer chamber has a second transfer port communicable with the second substrate processing chamber, and

at least the part of the buffer chamber is disposed above at least one of the first transfer port or the second transfer port when viewed from the side.

7. The substrate processing system of claim 6 , wherein the second height is higher than the first height.

8. A substrate transfer apparatus comprising:

a substrate transfer chamber connected to a substrate processing chamber; and

a buffer chamber connected to the substrate transfer chamber, the buffer chamber also connectable to a different substrate transfer chamber,

the buffer chamber having at least one substrate holder,

wherein at least a part of the buffer chamber and the substrate transfer chamber are vertically overlapped with each other when viewed from a top of the substrate transfer apparatus,

wherein the substrate transfer chamber has a transfer port communicable with the substrate processing chamber and a stepped side portion, a lower portion of the stepped side portion protruding more toward the buffer chamber than an upper side of the stepped side portion to form a rectangular protruding part, wherein the rectangular protruding part is entirely overlapped with at least the part of the buffer chamber when viewed from the top,

wherein at least a part of the transfer port and the rectangular protruding part are overlapped with each other when viewed from a side of the substrate processing system,

wherein the transfer port is not overlapped with the buffer chamber, when viewed from the side of the substrate transfer apparatus, and wherein an upper surface of the buffer chamber, an upper surface of the substrate transfer chamber, and an upper surface of the different substrate transfer chamber form the same plane.