Patent ID: 9333645
Filing Date: 2016-05-10
CPC Classification: B25J,G05B,G06F,H01L,Y02P,Y10S

Claim Text:
1. A computer implemented method for scheduling a dual-armed cluster tool with wafer revisiting for a transient process of a wafer fabrication system, the dual-armed cluster tool comprising a robot having two arms, and three process modules PMs, each for performing a wafer-processing Step, where PM i is used for performing a processing Step i of the three wafer-processing steps for each wafer, iεN 3 ={1, 2, 3}, the wafer revisiting comprising a wafer flow pattern as (PM 1 , (PM 2 , PM 3 ) 2 ) with (PM 2 , PM 3 ) 2 being a 2-revisiting process, the method comprising: obtaining, by a processor, a wafer processing time a determining, by a processor, a plurality of algorithms of the transient process based on a plurality of robot task sequences θs for the robot, a plurality of system states M if Π if Π if Π computing, by a processor, a time to reach the steady state from the initial state via performing each of the algorithms of the transient process based on the wafer processing time, the wafer loading time, the wafer unloading time, the moving time, and the swapping time; and determining, by a processor, a corresponding robot task sequences given by the one of the algorithms of the transient process having a minimal time to reach the steady state among the computed times, wherein the determined robot task sequences are used for scheduling the transient process.