Method for establishing a wafer testing recipe
A method and a system for establishing a wafer testing recipe are disclosed. The method may include acquiring images of a number of dice from a produced wafer; using at least part of the images to compose a reference-image; defining on the reference-image multiple “zones of interest; determining the Detection-Policy for each kind of zone of interest and determining the algorithm that will be used by each of the Detection-Policy; determining the parameters of each of the Detection-Policy's algorithms; determining the Reporting-policy; determining the Inspection-policy; and creating a “wafer testing recipe” by integrating of the testing reference of a typical die image, the zones of interest, the Detection-Policies, the parameters of the Detection-Policies' algorithms, the Reporting-Policies and the Inspection-Policies.
1. A method for establishing a wafer testing recipe comprising:
acquiring, by an automatic optical inspection (AOI) system, images of a number of dies from a produced wafer;
using, by an off-line system, at least a part of said images to compose a reference-image to be used as testing reference of a typical die image;
defining, by the off-line system, on said reference-image elements of a die pattern that differ from each other as different kinds of zones of interest;
determining, by the off-line system, Detection-Policies that comprise a Detection-Policy for each kind of zone of interest;
determining a Detection-Policy algorithm of each Detection-Policy;
determining, by the off-line system, parameters of each of said Detection-Policy algorithm;
determining, by the off-line system, Reporting-Policies that comprise a Reporting-policy for each kind of zone of interest by defining a set of defect classes that could be used during inspection of a specific lot of wafers;
determining, by the off-line system, Inspection-Policies that comprise an Inspection-policy for each kind of zone of interest, each Inspection-policy defining a behavior of an inspection system as a set of pre-defined logical rules;
establishing, by the off-line system, a wafer testing recipe by integrating of said testing reference of a typical die image, said defined zones of interest, Detection-Policies, parameters of said each Detection-Policy algorithm, said Reporting-Policies and said Inspection-Policies; wherein the wafer testing recipe comprises a sub-recipe for each kind of area of interest; and
performing, by the AOI system, an AOI process to recognize defects using the wafer testing recipe.
2. The method of claim 1 , comprising receiving, by the off-line system, a definition of at least one zone of interest from a user and detecting at least one other zone of interest said definition.
3. The method of claim 1 , further comprising fine tuning the wafer testing recipe by running the wafer testing recipe on another part of the images of the number of dies from the produced wafer and receiving from an operator at least one of a parameter overwrite and a decision overwrite.
4. The method of claim 1 , wherein at least one kind of zone of interest comprises multiple zones of interest that are similar to each other.
5. The method of claim 1 , further comprising importing a pre-defined geometrical figure as a zone of interest from other sources.
6. The method of claim 1 , comprising defining a priority of a pixel in a case that said pixel belongs to a number of zones of interest.