A robot assembly including multiple independently operable robot assemblies are provided for use in semiconductor wafer processing. The robot assembly includes independent co-axial upper and lower robot assemblies adapted to handle multiple objects. The upper robot is stacked above the lower robot and the two robots are mounted concentrically to allow fast wafer transfer. Concentric drive mechanisms may also be provided for imparting rotary motion to either rotate the robot assembly or extend an extendable arm assembly into an adjacent chamber. Each robot can be either a single blade robot or a dual blade robot. Also provided is an apparatus for processing semiconductor wafers comprising a pre/post process transfer chamber housing multiple independent robot assemblies and surrounded by a plurality of pre-process chambers and post process chambers. Within each process, pre-process and post-process chamber is an apparatus for holding a plurality of stacked wafers. The apparatus includes a wafer lifting and storing apparatus exhibiting a plurality of vertically movable lift pins surrounding the chamber pedestal. The lift pins are configured to receive and hold a plurality of stacked wafers, preferably two, therein.

A continuous motion robotic device including a first robotic arm, a second robotic arm, a third robotic arm, and a drive system. The robotic arms are coaxially arranged, each including an end effector for performing useful work on an object and can continuously rotate a full 360. The drive system commonly controls the three robotic arms and defines a central axis about which the device rotates. The device is capable of high-speed operation in that the robotic arms are sequentially presented to various work environment stations via rotation about the central axis. In one preferred embodiment, each of the robotic arms provides three degrees of freedom. In another preferred embodiment, each robotic arm includes at least a first primary joint and a second primary joint, with the first primary joints being coupled and the second primary joints being coupled. Alternatively, the primary joints are decoupled.

The present invention provides methods and apparatus for reducing particulate contamination during the processing of a substrate. In one embodiment, the method includes the step of preheating a substrate in a preheater to a desired temperature. The preheated substrate is transferred from the preheater to a buffer region having a pressure therein that is between about two (2) Torr and about seven hundred and sixty (760) Torr. The preheated substrate is transferred from the buffer region to a reaction chamber. Thermophoretic forces help repel particles away from the substrate surface during substrate transfer.

A robot assembly, including a central hub, has two arms arranged for independent rotation about the hub. Two carriers, oriented 180.degree. apart from each other, are coupled to an end of each of the arms. A drive is provided for rotating the arms in opposite directions to extend one or the other of said carriers radially from said central hub, and for rotating the arms in the same direction to effect rotation of the carriers.

A multi-layer sputter deposition chamber or cluster tool module is described. The sputter deposition chamber includes a plurality of magnetrons mounted on a rotatable member that defines an aperture. A predetermined one of the plurality of magnetrons is positionable proximate to a substrate in the sputter deposition chamber. A transport mechanism transports the substrate in a path of the sputtered ions in a first and a second direction that is substantially opposite to the first direction.