US 12,394,647 B2
Wafer shift detection
Ming-Sze Chen, Hsinchu (TW); Yuan-Hsin Chi, Taichung (TW); Hung-Chih Wang, Taichung (TW); and Sheng-Yuan Lin, Hsinchu (TW)
Assigned to TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Hsinchu (TW)
Filed on Jan. 4, 2023, as Appl. No. 18/093,085.
Claims priority of provisional application 63/409,355, filed on Sep. 23, 2022.
Prior Publication US 2024/0105480 A1, Mar. 28, 2024
Int. Cl. H01L 21/67 (2006.01); H01L 21/673 (2006.01); H01L 21/677 (2006.01)
CPC H01L 21/67265 (2013.01) [H01L 21/67326 (2013.01); H01L 21/67751 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method for detecting wafer shift of a wafer stored within a wafer storage elevator, comprising:
activating at least one laser at a first position to transmit a laser beam into an optical path that passes along a first storage elevator sidewall downward of the wafer storage elevator in an associated semiconductor manufacturing system to a first mirror arranged to reflect the laser beam to a second mirror arranged to reflect the laser beam along a second storage elevator sidewall upward to at least one receive sensor at a second position distinct from the first position;
generating a signal, in accordance with an output of the receive sensor, indicating whether a wafer alignment issue is present in the wafer storage elevator; and
continuing operation of the associated semiconductor manufacturing system in accordance with the signal indicating no wafer alignment issue;
wherein the first mirror and the second mirror are mounted on a storage elevator seat, the storage elevator seat located between a bottom of the first storage elevator sidewall and the second storage elevator sidewall, wherein in the optical path the first mirror is arranged to reflect the laser beam along the storage elevator seat to the second mirror.