Scanning framing blade apparatus

A lithographic system, comprising:

• an illumination source that projects radiation in the form of an illumination slot;
• a reticle stage that moves a reticle across the illumination slot during a substrate scanning process;
• a scanning framing blade apparatus that controls illumination onto the reticle by blocking portions of the reticle from the illumination slot, the scanning framing blade apparatus comprising:
• a) a stationary assembly having a plurality of magnets;
• b) first and second carriage assemblies, each of said first and second carriage assemblies having a plurality of coils, wherein said first and second carriage assemblies are supported on said stationary assembly by a plurality of air bearings, said air bearings permitting said first and second carriage assemblies to move in only one degree of freedom;
• c) first and second framing blades attached to said first and second carriage assemblies, respectively;
• and
• d) a controller coupled to said plurality of coils, wherein said controller is adapted to energize at least one of said plurality of coils, thereby causing at least one of said carriage assemblies and corresponding framing blade to move in said one degree of freedom to control illumination onto the reticle during a substrate scanning process;
• and
• a substrate stage that scans a substrate in synchronization with the motion of the reticle stage.

In a scanning framing blade apparatus comprising a stationary assembly, first and second carriage assemblies, each of said first and second carriage assemblies having a plurality of coils, first and second framing blades attached to said first and second carriage assemblies, respectively, a controller coupled to said plurality of coils, wherein said controller is adapted to energize at least one of said plurality of coils, and a position determination mechanism that provides framing blade position information to said controller, a method for performing a scanning operation, the method comprising

• receiving a command from a master control system;
• receiving framing blade position information from the position determination mechanism;
• processing the position information;
• and
• energizing the coils in at least one of the carriage assemblies, thereby driving the first and second framing blades in a manner that is consistent with the command received from the master control system.