Method and apparatus for flip-chip bonding
View Patent ↗Provided are a laser flip-chip bonding method having high productivity and excellent bonding reliability and a flip-chip bonder employing the same. The flip-chip bonder includes: a bonding stage on which a substrate rests; a bonding head picking up a semiconductor chip and attaching the semiconductor chip to the substrate; and a semiconductor chip heating unit heating the semiconductor chip to a bonding temperature. The semiconductor chip heating unit includes: a laser light source; and a lens assembly refracting a laser beam emitted by the laser light source to a top surface of the semiconductor chip so that a central position of the laser beam varies across the top surface of the semiconductor chip.
1. A flip-chip bonding method comprising:
disposing a semiconductor chip on a substrate;
aligning bumps of the semiconductor chip with bumps of the substrate;
generating a laser beam by a laser light source;
moving the laser beam on a top surface of the semiconductor chip to substantially irradiate the top surface; and
pressing the semiconductor chip on the substrate to bond said bumps of the semiconductor chip with said bumps of the substrate.
2. The flip-chip bonding method of claim 1 , wherein the moving step comprises:
disposing a first scan mirror in an optical path between the laser light source and the semiconductor chip; and
rotating the first scan mirror continuously about a first axis to refract the laser beam along the top surface of the semiconductor chip in a first direction.
3. The flip-chip bonding method of claim 2 wherein the moving step further comprises:
disposing a second scan mirror in optical communication with the first scan mirror; and
rotating the second scan mirror continuously about a second axis to refract the laser beam along the top surface of the semiconductor chip in a second direction.
4. The flip-chip bonding method of claim 3 , wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam with a constant linear velocity along the top surface.
5. The flip-chip bonding method of claim 3 wherein the first and second scan mirrors are rotated independently.
6. The flip-chip bonding method of claim 3 further comprising the step of orienting the first axis and the second axis to be generally perpendicular.
7. The flip-chip bonding method of claim 3 wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam along at least one of a polylinear and a curvilinear path.
8. The flip-chip bonding method of claim 1 , further comprising:
determining a size of the semiconductor chip; and
adjusting a diameter of the laser beam according to the size from the determining step.
9. A flip-chip bonding method comprising:
moving a laser beam emitted from a laser light source on a surface of a semiconductor chip, the surface being opposite of a bump surface of the semiconductor chip; and
contacting bumps on the bump surface to bumps on a surface of a substrate,
wherein the moving step comprises:
configuring a first scan mirror in an optical path between the laser light source and the semiconductor chip; and
rotating the first scan mirror about a first axis to direct the laser beam along the top surface of the semiconductor chip in a first direction.
10. The method of claim 9 wherein the moving step further comprises:
configuring a second scan mirror in optical communication with the first scan mirror; and
rotating the second scan mirror about a second axis to direct the laser beam along the top surface of the semiconductor chip in a second direction.
11. The method of claim 10 wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam with a constant linear velocity along the top surface.
12. The method of claim 10 wherein the first and second scan mirrors are rotated independently.
13. The method of claim 10 further comprising the step of orienting the first axis and the second axis to be generally perpendicular.
14. The method of claim 10 wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam along at least one of a polylinear and a curvilinear path.
15. The method of claim 9 further comprising:
determining a size of the semiconductor chip; and
adjusting a diameter of the laser beam according to the size from the determining step.
16. A flip-chip bonding method comprising:
determining a size of the semiconductor chip;
adjusting a diameter of the laser beam according to the size from the determining step;
moving a laser beam emitted from a laser light source on a surface of a semiconductor chip, the surface being opposite of a bump surface of the semiconductor chip; and
contacting bumps on the bump surface to bumps on a surface of a substrate.
17. The method of claim 16 wherein the moving step comprises:
configuring a first scan mirror in an optical path between the laser light source and the semiconductor chip; and
rotating the first scan mirror about a first axis to direct the laser beam along the top surface of the semiconductor chip in a first direction.
18. The method of claim 17 wherein the moving step further comprises:
configuring a second scan mirror in optical communication with the first scan mirror; and
rotating the second scan mirror about a second axis to direct the laser beam along the top surface of the semiconductor chip in a second direction.
19. The method of claim 18 wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam with a constant linear velocity along the top surface.
20. The method of claim 18 wherein the first and second scan mirrors are rotated independently.
21. The method of claim 18 further comprising the step of orienting the first axis and the second axis to be generally perpendicular.
22. The method of claim 18 wherein the first and second scan mirrors cooperate in the steps of rotating the first scan mirror and rotating the second scan mirror to move the laser beam along at least one of a polylinear and a curvilinear path.