A cluster tool system, including: a load lock; a first wafer transfer module; a buffer module; a second wafer transfer module; wherein the load lock, the first wafer transfer module, the buffer module, and the second wafer transfer module are positioned in a linear arrangement; a first process module connected to the first wafer transfer module on a first side of the linear arrangement; a second process module connected to the second wafer transfer module on the first side; a third process module connected to the first wafer transfer module on a second side of the linear arrangement that is opposite the first side; a fourth process module connected to the second wafer transfer module on the second side; a first ladder assembly connected to the buffer module on the first side; a second ladder assembly connected to the buffer module on the second side.