Patent ID: 11869756
Assignee: TOKYO ELECTRON LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 17:
18. A method of optimizing a recipe for a plasma process comprising:
(a) building a virtual metrology (VM) model that predicts a wafer characteristic resulting from the plasma process based on a plasma parameter;
(b) building a control model that describes a relationship between the plasma parameter and a recipe parameter;
(c) measuring the wafer characteristic after performing the plasma process according to the recipe;
(d) determining whether the wafer characteristic is within a predetermined range;
(e) calibrating the VM model and the control model based on the wafer characteristic;
(f) optimizing the recipe by updating the plasma parameter based on the wafer characteristic using the VM model and updating the recipe parameter based on the plasma parameter using the control model; and
(g) repeating (c), (d), (e) and (f) until the wafer characteristic is within the predetermined range, wherein
the plasma process is an etching process,
the wafer characteristic measured is CD,
the plasma parameter comprises neutral density of Cl, and
the recipe parameter comprises a flow rate of Cl2.