Semiconductor device and method of manufacture
A semiconductor device has a conductive via laterally separated from the semiconductor, an encapsulant between the semiconductor device and the conductive via, and a mark. The mark is formed from characters that are either cross-free characters or else have a overlap count of less than two. In another embodiment the mark is formed using a wobble scan methodology. By forming marks as described, defects from the marking process may be reduced or eliminated.
1. A method of manufacturing a semiconductor device, the method comprising:
placing a protective layer over a semiconductor device and a via separated from the semiconductor device, wherein the semiconductor device is electrically connected to the via, the semiconductor device and the via being surrounded by an encapsulant; and
marking the protective layer by exposing the protective layer to a plurality of offset laser pulses, wherein the marking creates a cross-free character and wherein each of the plurality of offset laser pulses removes a portion of the protective layer.
2. The method of claim 1 , wherein the cross-free character is an alphanumeric character.
3. The method of claim 1 , wherein at least one of the plurality of offset laser pulses has a diameter of between about 20 μm and about 120 μm.
4. The method of claim 1 , wherein a first one of the plurality of offset laser pulses is offset from an adjacent one of the offset laser pulses by a pitch of between about 2 μm and about 70 μm.
5. The method of claim 1 , wherein after the marking the protective layer the protective layer has multiple different kerf depths.
6. The method of claim 1 , wherein the cross-free character has a portion with a total accumulated overlap of between about 100% and about 400%.
7. The method of claim 1 , wherein the marking the protective layer forms a marking path, the marking path having an angle of between about 20° and about 30°.
8. A method of manufacturing a semiconductor device, the method comprising:
receiving a protective material over an encapsulant, the encapsulant encapsulating a semiconductor die and a conductive via laterally separated from the semiconductor die; and
exposing the protective material to a plurality of separate laser pulses to remove portions of the protective material and form a character, wherein the separate laser pulses generate a character with an overlap count of less than two and wherein the character has a bottom surface which comprises the protective material.
9. The method of claim 8 , wherein the plurality of separate laser pulses generates the character with an overlap count of less than one.
10. The method of claim 8 , wherein a first line of the character partially intersects a second line of the character at a partial intersection.
11. The method of claim 10 , wherein a laser beam pulse exposure at the partial intersection has an accumulated overlap percentage greater than about 376% and less than about 752%.
12. The method of claim 10 , wherein the partial intersection has a first depth of between about 5 μm and about 18 μm.
13. The method of claim 8 , wherein the character has a marking path, the marking path having an angle of between about 20° and about 90°.
14. The method of claim 8 , wherein the separate laser pulses generate a character with an overlap count of greater than one.
15. A method of manufacturing a semiconductor device, the method comprising:
receiving a layer of material over a semiconductor die, an encapsulant, and a via, wherein the via is laterally separated from and electrically connected to the semiconductor die; and
marking the layer of material with a plurality of laser pulses, wherein each of the plurality of laser pulses has a diameter of less than about 100 μm, removes material from the layer of material, and each of which is aligned along a circular trace path.
16. The method of claim 15 , wherein the marking the layer of material is performed at least in part with a wobble marking process.
17. The method of claim 15 , wherein the circular trace path extends from a first line to a second line parallel with the first line.
18. The method of claim 17 , wherein a distance between the first line and the second line is between about 80 μm and about 200 μm.
19. The method of claim 17 , further comprising a centerline between the first line and the second line, wherein the circular trace path crosses the centerline at a first point and at a second point, a distance between the first point and the second point between about 50 μm and about 200 μm.
20. The method of claim 15 , wherein the layer of material is a polymer layer.