Substrate processing apparatus

Patent metadata

Field	Value
Publication number	US-12206342-B2
Application number	US-202218050300-A
Country	US
Kind code	B2
Filing date	Oct 27, 2022
Priority date	Oct 29, 2021
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

A linear electrical machine including a frame with a level reference plane, an array of electromagnets connected to the frame and coupled to an alternating current power source energizing each electromagnet, at least one reaction platen of paramagnetic, diamagnetic, or non-magnetic conductive material disposed to cooperate with the electromagnets of the array of electromagnets 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 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 the alternating current power source and configured so as to sequentially excite the electromagnets with multiphase alternating current with a predetermined excitation characteristic so that each reaction platen is levitated and propelled with up to six degrees of freedom.

First claim

What is claimed is:

1. A linear electrical machine comprising:
a frame with a level reference plane;
an array of electromagnets, connected to the frame 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, and each of the electromagnets being coupled to a multiphase alternating current power source energizing each electromagnet;
at least one reaction platen of paramagnetic, diamagnetic, or non-magnetic conductive material disposed to cooperate with the electromagnets of the array of electromagnets so that excitation of the electromagnets with multiphase 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 the multiphase alternating current power source and configured so as to sequentially excite the electromagnets with the multiphase alternating current with a predetermined excitation characteristic so that each reaction platen has six degrees of freedom reaction platen control and is levitated and propelled with at least four degrees of freedom from the six degrees of freedom reaction platen control, wherein the controller is configured so as to determine reaction platen position feedback, in at least one degree of freedom from the six degrees of freedom reaction platen control, from variance in the predetermined excitation characteristic of the alternating current of at least one electromagnet effecting levitation or propulsion of the reaction platen, wherein the variance in the predetermined excitation characteristic defines self-deterministic reaction platen position feedback of each of the at least one electromagnet, of the array of electromagnets, effecting levitation or propulsion of the reaction platen.

2. The linear electric machine of claim 1 , wherein the six degrees of freedom include at least one of attitude control and yaw control, the at least one of the attitude control and the yaw control are effected with a common set of electromagnets of the array of electromagnets, where each electromagnet 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 the up to six at least four degrees of freedom including at least one of reaction platen attitude and reaction platen yaw at least with the reaction platen levitated.

3. The linear electric machine of claim 1 , wherein the self-deterministic reaction platen position feedback is an absolute position feedback.

4. The linear electric machine of claim 1 , wherein the predetermined excitation characteristic is one or more of inductance, a power factor, and a lag between voltage and current of the multiphase alternating current.

5. The linear electric machine of claim 1 , wherein:
the at least one reaction platen comprises more than one reaction platen, each of the more than one reaction platen having a corresponding shape that defines a respective power factor signature; and
the controller is configured to determine a position of each reaction platen based on the respective power factor signature.

6. The linear electrical machine of claim 1 , wherein a frequency is superimposed on a fundamental frequency of a voltage generated by the multiphase alternating current power source, the frequency being separate and distinct from the fundamental frequency so as to decouple position feedback determination from levitation and propulsion of the at least one reaction platen.

7. The linear electrical machine of claim 1 , wherein the controller controls the at least four degrees of freedom, generated by the array of electromagnets, including at least the reaction platen attitude with the reaction platen levitated and propelled so as to move relative to the array of electromagnets along the at least one drive line from a first predetermined position with respect to the frame to a second different predetermined position with respect to the frame.

8. The linear electrical machine of claim 1 , wherein the controller controls the at least four degrees of freedom, generated by the array of electromagnets, including at least the reaction platen attitude and the reaction platen yaw with the reaction platen levitated and stationary relative to the array of electromagnets in a predetermined position along the at least one drive line with respect to the frame.

9. The linear electrical machine of claim 1 , wherein the controller controls the propulsion forces, generated by the array of electromagnets, across the reaction platen so as to impart a controlled yaw moment on the reaction platen, yawing the reaction platen about a yaw axis, substantially normal to the drive plane, from a first predetermined orientation relative to the frame, to a second different predetermined orientation relative to the frame.

10. The linear electrical machine of claim 1 , wherein the controller controls the propulsion forces, generated by the array of electromagnets, so as to impart a moment couple on the reaction platen effecting controlled yaw of the reaction platen so as to effect at least one of positioning and centering of a wafer payload on the reaction platen relative to a predetermined wafer holding location of the frame.

11. The linear electrical machine of claim 1 , wherein the controller controls the levitation forces, generated by the array of electromagnets, so as to impart differential levitation forces across the reaction platen that effect a controlled inclination of the reaction platen, relative to the drive plane, that controls a predetermined reaction platen attitude in at least one of reaction platen pitch and reaction platen roll.

12. The linear electrical machine of claim 1 , wherein the controller controls the levitation forces, generated by the array of electromagnets, so as to effect a predetermined bias attitude of the reaction platen, relative to the drive plane, that imparts a bias reaction force, from a reaction platen payload seating surface on a payload supported by the reaction platen seating surface, in a direction countering payload inertial force arising from acceleration of the reaction platen along the drive plane.

13. The linear electrical machine of claim 1 , wherein the controller controls excitation of the electromagnets of the array of electromagnets so as to set the reaction platen attitude to bias the reaction platen against inertial forces tending to displace a payload, seated against the reaction platen, relative to the reaction platen along a seat between the payload and the reaction platen.

14. The linear electrical machine of claim 1 , further comprising a passive vibration compensator having a natural frequency mode tuned to compensate for vibration of the at least one reaction platen under levitation propulsion forces so as to effect a substantially vibration free end effector with respect to the end effector natural vibration frequency modes, wherein the at least one reaction platen includes a respective end effector.

15. 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

Assignees

• Brooks Automation Us Llc

Inventors

• Moura Jairo T
• Tsang Vincent
• Saini Karanjit
• Caveney Robert T
• May Robert C
• Babbs Daniel

Classifications

• H10P72/3306

  Horizontal transfer of a single workpiece · CPC title

• H10P72/0608

  of substrates stored in a container, a magazine, a carrier, a boat or the like · CPC title

• H10P72/7602

  the wafers being placed on a robot blade or gripped by a gripper for conveyance · CPC title

• H10P72/3302

  Mechanical parts of transfer devices · CPC title

• H10P72/3216

  using a general scheme of a conveying path within a factory · CPC title