US 11,669,079 B2
Tool health monitoring and classifications with virtual metrology and incoming wafer monitoring enhancements
Jun Shinagawa, Fremont, CA (US); Toshihiro Kitao, Austin, TX (US); Hiroshi Nagahata, Miyagi (JP); and Chungjong Lee, Miyagi (JP)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Jul. 12, 2021, as Appl. No. 17/373,078.
Prior Publication US 2023/0009419 A1, Jan. 12, 2023
Int. Cl. G05B 19/418 (2006.01); H01L 21/66 (2006.01); H05H 1/46 (2006.01)
CPC G05B 19/41875 (2013.01) [H01L 22/12 (2013.01); H05H 1/46 (2013.01); G05B 2219/45031 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method of evaluating tool health of a plasma tool, the method comprising:
providing a classification model that identifies a plurality of failure modes of the plasma tool;
performing an initial test on an incoming wafer by performing a measurement on the incoming wafer;
determining that the incoming wafer meets a preset requirement based on the initial test, in response to determining that the incoming wafer meets a preset requirement based on the initial test, executing a plasma etching process, and predicting a wafer characteristic associated with the plasma etching process using a virtual metrology (VM) model that is configured to predict the wafer characteristic based on parameters measured by module sensors and in-situ sensors of the plasma tool;
determining that the wafer characteristic predicted by using the VM model is outside a pre-determined range and identifying a current failure mode using the classification model; and
based on the current failure mode, adjusting a recipe of the plasma etching process or taking a corrective action for the plasma tool.