Defect estimation device and method and inspection system and method
AssigneeNuFlare Technology, Inc.
InventorsHideo Tsuchiya, Takayuki Abe
Life of this patent
Estimating the term…
Abstract
Acquired mask data of a defect portion is sent to a simulated repair circuit 300 to be simulated. The simulation of the acquired mask data 204 is returned to the mask inspection results 205 and thereafter sent to a wafer transfer simulator 400 along with a reference image at the corresponding portion. A wafer transfer image estimated by the wafer transfer simulator 400 is sent to a comparing circuit 301. When it is determined that there is a defect in the comparing circuit 301, the coordinates and the wafer transfer image which is a basis for the defect determination are stored as transfer image inspection results 206. The mask inspection results 205 and the transfer image inspection result 206 are then sent to the review device 500.
Claims4
An inspection method characterized by comprising:
- illuminating light to a sample formed with a pattern, forming an image of the sample on an image sensor through an optical system, obtaining an optical image of the sample from the image sensor, comparing the obtained optical image with a reference image and, when a difference exceeds at least one of a plurality of threshold values, determining that there is a defect;
- reviewing the optical image including the defect and the reference image corresponding to the optical image and determining necessity of repair applied to the defect;
- determining whether or not each transfer image of the optical image and the reference image is required to be estimated;
- when each of the transfer images is required to be estimated, estimating and comparing each of the transfer images, when a difference exceeds at least one of the threshold values, determining that there is a defect, reviewing each of the transfer images, and determining the necessity of the repair applied to the defect;
- and
- when each of the transfer images is not required to be estimated, reviewing an optical image including another defect and a reference image corresponding to the optical image including another defect, and determining the necessity of the repair applied to the another defect.
A defect estimation device comprising:
- an estimation part configured to utilize a reference image of a mask pattern and a corresponding optical image, and obtain an estimated reference pattern image and a first candidate pattern image of the mask pattern transferred to a substrate by a lithography process;
- and
- a simulation repair part configured to simulate a repair to the optical image based on the reference pattern image and the first candidate pattern image,
- wherein second candidate pattern images of the mask pattern transferred to the substrate by the lithography process are estimated using a simulation repair image of the optical image to which the repair is simulated by the simulation repair part, and
- the reference pattern image and each of the second candidate pattern images are compared with each other to confirm whether a defect is eliminated.
A defect estimation device comprising:
- a first estimation part configured to utilize a reference image of a mask pattern and a corresponding optical image, and estimate a first reference pattern image and a first candidate pattern image of the mask pattern transferred to a substrate by a first lithography process;
- a simulation repair part configured to simulate a repair to the optical image based on the reference pattern image and the first candidate pattern image;
- and
- a second estimation part configured to utilize the reference image and a simulation repair image of the optical image to which the repair is simulated by the simulation repair part, and estimate a second reference pattern image and a second candidate pattern image of the mask pattern transferred to the substrate by a second lithography process which is the same as or more advanced than the first lithography process,
- wherein the second reference pattern image and the second candidate pattern image are compared with each other to confirm whether a defect is eliminated.
Dependencies are inferred from the claim text.