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US 9,437,506 B2Granted
Semiconductor defect characterization
AssigneeLattice Semiconductor Corporation
InventorsUwe Hessinger, Brett Schafman, Wendy Chan
Life of this patent
Estimating the term…
Abstract
The defect-containing die identified from an inspection layer analysis subsequent to a manufacturing step for a wafer including a plurality of die and as well as the faulty die identified from a fault testing of the wafer are processed to identify a subset of the die that both contain a defect and are faulty. A probability analysis is performed to determine a confidence level of whether the die in the subset are faulty due to their defects.
Claims18
A method of semiconductor manufacture, comprising:
- in a computer for analyzing a wafer having a number of die (N), counting a number (H) of the die that are included in both a subset of the N die, with a number (D) members, having a defect, as identified from an inspection layer analysis of the wafer, and which also are included in a subset of the N die, which are failing, having a number of failing die (F) identified from a fault test of the wafer;
- in the computer, dividing H into a number (Hk) of die that are postulated to have a defect that caused a die failure and into a number (Hb) of the die that are postulated to have a defect that did not cause a die failure, wherein the division is based upon the numbers H, D, F, and N, and H=Hk+Hb;
- in the computer, calculating a number (Hr) of die that has the same proportionality to F as does D to N;
- in the computer, computing a probability (P(H)) of H occurring and a probability (P(Hr)) of Hr occurring;
- and
- adjusting a wafer manufacturing step based at least on P(H) and P(Hr).
3 more elements
A system, comprising:
- a computer configured to:
- count a number (H) of the die on a wafer that are included in both a number D of die on the wafer that have a defect as identified from an inspection layer analysis and included in a number (F) of failing die on the wafer identified from a fault test;
- divide the number H into a number (Hk) of die that are postulated to have a defect that caused a die failure and into a number (Hb) of the die that are postulated to have a defect that did not cause a die failure, wherein the division is based upon the numbers H, D, F, and N;
- calculate a number (Hr) of die that has the same proportionality to F as the proportionality of D to N;
- and
- compute a probability (P(H)) of H occurring and a probability (P(Hr)) of Hr occurring.
3 more elements
Dependencies are inferred from the claim text.