초록 ▼

A method for physically marking, on silicon wafers, of integrated circuits deemed to be defective during a testing step, so as to modify the visual appearance of the surface of these circuits, wherein the marking is done by the exposure of the circuits to a laser beam. The disclosure also relates to

A method for physically marking, on silicon wafers, of integrated circuits deemed to be defective during a testing step, so as to modify the visual appearance of the surface of these circuits, wherein the marking is done by the exposure of the circuits to a laser beam. The disclosure also relates to an instrument enabling the method to be implemented.

대표청구항 ▼

1. A method for physically marking, on a silicon wafer, a surface of an integrated circuit deemed to be defective during a testing step so as to modify a visual appearance of the surface, the method comprising steps of: identifying a defective integrated circuit; and marking the defective integr

1. A method for physically marking, on a silicon wafer, a surface of an integrated circuit deemed to be defective during a testing step so as to modify a visual appearance of the surface, the method comprising steps of: identifying a defective integrated circuit; and marking the defective integrated circuit at a plurality of locations by exposing the surface of the defective integrated circuit to laser radiation of sufficient magnitude such that the defective integrated circuit will not operate. 2. The method according to claim 1, wherein the integrated circuit includes a plurality of layers, and wherein the step of marking includes a step of melting at least a part of each of the plurality of layers. 3. The method according to claim 1 wherein the integrated circuit is covered with at least one passivation layer having a thickness, and wherein the step of marking includes a step of melting the surface of the defective integrated circuit to a depth greater than the thickness of the passivation layer. 4. The method according to claim 1, wherein energy density of the laser radiation at the surface of the defective integrated circuit is in the range of 200 to 1200 millijoules per square millimeter. 5. The method according to claim 1, wherein the laser radiation is focused in such a way that a marking diameter is variable. 6. The method according to claim 5, wherein the marking diameter is between 300 and 1000 micrometers. 7. The method of claim 1, wherein the step of marking includes a step of marking the surface of the defective integrated circuit at a plurality of locations in a predetermined geometric pattern. 8. A method of inspecting a plurality of integrated circuits on a silicon wafer, the method comprising steps of: testing the plurality of integrated circuits; identifying defective integrated circuits; and exposing a surface of each of the defective integrated circuits to laser radiation of sufficient magnitude such that the defective integrated circuit will not operate, the step of exposing including a step of creating a mark on the surface of each of the defective integrated circuits at a plurality of locations. 9. The method according to claim 8, wherein each of the integrated circuits includes a plurality of layers, and wherein the step of exposing includes a step of melting at least a part of each of the plurality of layers of each of the defective integrated circuits. 10. The method according to claim 8 wherein the integrated circuits are covered with at least one passivation layer having a thickness, and wherein the step of exposing includes a step of melting the surface of each of the defective integrated circuits to a depth greater than the thickness of the passivation layer. 11. The method according to claim 8, wherein the step of exposing includes a step of generating an energy density of the laser radiation at the surface of the defective integrated circuit is in the range of 200 to 1200 millijoules per square millimeter. 12. The method according to claim 8, wherein the mark has a mark diameter, and wherein the step of exposing includes a step of focusing the laser radiation to control the mark diameter. 13. The method according to claim 12, wherein the mark diameter is between 300 and 1000 micrometers. 14. The method of claim 8, wherein the step of marking includes a step of marking the surface of the defective integrated circuir at a plurality of locations in a predetermined geometric pattern.