Integrated rework modules on resist track
Original Publication Date: 2002-Jun-01
Included in the Prior Art Database: 2003-Jul-23
Ralf Schuster: AUTHOR [+2]
Lithography tools have set examples for productivity improvement in IC manufacturing. They have evolved from single tools to lithography photocells with integrated exposure tools and photoresist tracks that handle wafers from a common loadport. The next step has been to integrate metrology modules (such as a ashing chamber) on the track.
Integrated rework modules on re-sist track
Idee: Ralf Schuster, Dresden;
David Zeglinski, Dresden
Lithography tools have set examples for productivityimprovement in IC manufacturing. They haveevolved from single tools to lithography photocellswith integrated exposure tools and photoresist tracksthat handle wafers from a common loadport. Thenext step has been to integrate metrology modules(such as a ashing chamber) on the track.
One of the major additions to cycle time in the li-thography area is wafers waiting for rework proc-essing that is usually done by stripping the photore-sists in a wet clean or a ash chamber. These additionsto the cycle time include transfer times, operatoravailability and tool availability.
This invention proposes to integrate an ash chamberand/or a wet clean spray tool into a photoresist track.The rework modules would become additional mod-ules which would solve logistic and transportationissues. In comparison to a stand-alone rework mod-ule, cost would be reduced since all wafers handlingis done by the track.
Together with integrated metrology modules suchCD, overlay or macro inspection tools this techniqueshould significantly reduce the cycle time, simplifythe material handling and reduce overall hardwarecost. One of the main advantages of this approach isthe flexibility to measure all wafers and rework onlythose wafers of a lot that are out spec. This wouldalso increase product yield that is impacted by there...