Patent ID: 9607265
Date: 2017-03-28
CPC Classifications: G06N

Claim:
1. A method of fast neural network training for library-based critical dimension (CD) metrology for a grating structure, the method comprising: providing a training target for a first neural network; training the first neural network, the training of the first neural network including use of a validation data set, the training comprising starting with a first number of neurons and iteratively increasing the number of neurons until the training target is reached using a second, larger, number of neurons, wherein the training of the first neural network includes stopping iterations for the training of the first neural network upon the occurrence of the following: generating a second neural network based on the training and the second number of neurons; providing a spectral library based on the second neural network, the spectral library including a simulated spectrum for the grating structure; and comparing the simulated spectrum to a sample spectrum for the grating structure.