A substrate processing tool, comprising: a vacuum transfer module; and at least one process module comprising a plurality of processing stations (1, 2, 3, 4), the at least one process module coupled to the vacuum transfer module, wherein at least one of the at least one process modules includes a mechanical indexer, the mechanical indexer comprising: a first arm (208,324) having a first end effector (216, 332) and a second end effector (220, 336), and a first spindle (240, 348), wherein the first arm is configured to rotate on the first spindle (240, 348) to (i) selectively position the first end effector (216, 332) of the first arm (208, 324) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the first arm at the plurality of processing stations of the substrate processing tool; and a second arm (212, 328) having a first end effector (224, 340) and a second end effector (228, 344) and a second spindle (244, 352), wherein the second arm is configured to rotate on the second spindle (244, 352) to (i) selectively position the first end effector (224, 340) of the second arm (212, 328) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the second arm at the plurality of processing stations of the substrate processing tool, wherein at least one of the plurality of processing stations (1, 2, 3, 4) is configured to correspond to a load station of the substrate processing tool, and wherein the first arm is configured to rotate independently of the second arm such that the first end effector (208, 324) or the second end effector (220, 336) of the first arm (208, 324) may be positioned over or below the first end effector (224, 340) or the second end effector (228, 344) of the second arm (212, 328) while positioned at the load station. a vacuum transfer module; and at least one process module comprising a plurality of processing stations (1, 2, 3, 4), the at least one process module coupled to the vacuum transfer module, wherein at least one of the at least one process modules includes a mechanical indexer, the mechanical indexer comprising: a first arm (208,324) having a first end effector (216, 332) and a second end effector (220, 336), and a first spindle (240, 348), wherein the first arm is configured to rotate on the first spindle (240, 348) to (i) selectively position the first end effector (216, 332) of the first arm (208, 324) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the first arm at the plurality of processing stations of the substrate processing tool; and a second arm (212, 328) having a first end effector (224, 340) and a second end effector (228, 344) and a second spindle (244, 352), wherein the second arm is configured to rotate on the second spindle (244, 352) to (i) selectively position the first end effector (224, 340) of the second arm (212, 328) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the second arm at the plurality of processing stations of the substrate processing tool, wherein at least one of the plurality of processing stations (1, 2, 3, 4) is configured to correspond to a load station of the substrate processing tool, and wherein the first arm is configured to rotate independently of the second arm such that the first end effector (208, 324) or the second end effector (220, 336) of the first arm (208, 324) may be positioned over or below the first end effector (224, 340) or the second end effector (228, 344) of the second arm (212, 328) while positioned at the load station. a first arm (208,324) having a first end effector (216, 332) and a second end effector (220, 336), and a first spindle (240, 348), wherein the first arm is configured to rotate on the first spindle (240, 348) to (i) selectively position the first end effector (216, 332) of the first arm (208, 324) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the first arm at the plurality of processing stations of the substrate processing tool; and a second arm (212, 328) having a first end effector (224, 340) and a second end effector (228, 344) and a second spindle (244, 352), wherein the second arm is configured to rotate on the second spindle (244, 352) to (i) selectively position the first end effector (224, 340) of the second arm (212, 328) at the plurality of processing stations (1, 2, 3, 4) of the substrate processing tool and (ii) selectively position the second end effector of the second arm at the plurality of processing stations of the substrate processing tool, wherein at least one of the plurality of processing stations (1, 2, 3, 4) is configured to correspond to a load station of the substrate processing tool, and wherein the first arm is configured to rotate independently of the second arm such that the first end effector (208, 324) or the second end effector (220, 336) of the first arm (208, 324) may be positioned over or below the first end effector (224, 340) or the second end effector (228, 344) of the second arm (212, 328) while positioned at the load station.