Substrate process apparatus

An electromagnetic conveyor substrate transport apparatus comprising:

• a chamber configured to hold a sealed atmosphere therein, and having a level reference plane and at least one substrate pass through opening for transferring a substrate in and out of the chamber through the opening;
• an array of electromagnets, connected to the chamber to form a drive plane at a predetermined height relative to the level reference plane, the array of electromagnets being arranged so that a series of electromagnets of the array of electromagnets define at least one drive line within the drive plane, electromagnets in the series of electromagnets being grouped into at least one multiphase actuator unit, and each of the at least one multiphase actuator unit being coupled to a multiphase alternating current power source;
• at least one reaction platen of paramagnetic, diamagnetic, or non-magnetic conductive material disposed to cooperate with the electromagnets of the at least one multiphase actuator unit so that excitation of the electromagnets with alternating current generates levitation and propulsion forces against the reaction platen that controllably levitate and propel the reaction platen along the at least one drive line, in a controlled attitude relative to the drive plane;
• and
• a controller operably coupled to the array of electromagnets and alternating current power source and configured so as to sequentially excite the electromagnets with multiphase alternating current so that a reaction platen is levitated and propelled, wherein each alternating current phase, of the multiphase alternating current, is dynamically allocated between respective electromagnets so that the alternating current phase of each respective electromagnet, of the electromagnet group of the at least one multiphase actuator unit, changes from a first alternating current phase to a second different alternating current phase so in effect the electromagnet group moves virtually and the at least one multiphase actuator unit formed by the electromagnet group moves virtually via dynamic phase allocation along the drive line.

A method for a linear electrical machine, the method comprising:

• providing the linear electrical machine with a frame, the frame having a level reference plane;
• forming a drive plane with an array of electromagnets connected to the frame, the drive plane is located at a predetermined height relative to the level reference plane, the array of electromagnets being arranged so that a series of electromagnets of the array of electromagnets define at least one drive line within the drive plane, and each of the electromagnets being coupled to an alternating current power source energizing each electromagnet;
• providing at least one reaction platen of paramagnetic, diamagnetic, or non-magnetic conductive material disposed to cooperate with the electromagnets of the array of electromagnets;
• and
• exciting the electromagnets with alternating current to generate levitation and propulsion forces against the reaction platen that controllably levitate and propel the reaction platen along the at least one drive line, in a controlled attitude relative to the drive plane;
• wherein the electromagnets are sequentially excited, with a controller operably coupled to the array of electromagnets and the alternating current power source, with multiphase alternating current so that each reaction platen is levitated and propelled with up to six degrees of freedom including at least one of attitude control and yaw control with a common set of the electromagnets, each of which generates, from excitation with common multiphase alternating current having a single common frequency per phase, both the levitation and the propulsion forces against the reaction platen so as to control the reaction platen with up to six degrees of freedom including at least one of reaction platen attitude and reaction platen yaw at least with the reaction platen levitated.