公开(公告)号：US11380594B2

公开(公告)日：2022-07-05

申请号：US15903693

申请日：2018-02-23

Applicant: KLA-TENCOR CORPORATION

Inventor： Tianrong Zhan ,  Yin Xu ,  Liequan Lee

IPC: H01L21/66 ,  G06N3/04 ,  G01N21/88 ,  G01N21/95 ,  G06N3/08

Abstract: Machine learning techniques are used to predict values of fixed parameters when given reference values of critical parameters. For example, a neural network can be trained based on one or more critical parameters and a low-dimensional real-valued vector associated with a spectrum, such as a spectroscopic ellipsometry spectrum or a specular reflectance spectrum. Another neural network can map the low-dimensional real-valued vector. When using two neural networks, one neural network can be trained to map the spectra to the low-dimensional real-valued vector. Another neural network can be trained to predict the fixed parameter based on the critical parameters and the low-dimensional real-valued vector from the other neural network.