US 7,321,426 B1
Optical metrology on patterned samples
Leonid Poslavsky, Belmont, Calif. (US); and Carlos L. Ygartua, Palo Alto, Calif. (US)
Assigned to KLA-Tencor Technologies Corporation, Milpitas, Calif. (US)
Filed on Jun. 02, 2004, as Appl. No. 10/859,637.
Int. Cl. G01J 4/00 (2006.01); G01B 11/00 (2006.01)
U.S. Cl. 356—369  [356/401] 42 Claims
OG exemplary drawing
 
1. A method for operating an optical metrology tool, the method comprising:
collecting a first set of optical metrology data from a first patterned target, the first patterned target comprising a first set of one or more thin films on a first patterned layer;
determining a first value set for one or more metrology attributes of the first set of one or more thin films;
collecting a second set of optical metrology data from a second patterned target, the second patterned target comprising a second set of one or more thin films on a second patterned layer, the second patterned layer being substantially similar to the first patterned layer;
determining a second value set for the one or more metrology attributes of the second set of one or more thin films;
generating an empirical model using the first set of optical metrology data, the second set of optical metrology data, the first value set, and the second value set;
collecting a third set of optical metrology data from a third patterned target on a first test sample, the third patterned target comprising a third set of one or more thin films on a third patterned layer, the third patterned layer being substantially similar to the first patterned layer;
determining a third value set for the one or more metrology attributes of the third set of one or more thin films using the empirical model; and
outputting the third value set as attribute values of the first test sample.