Standoff height improvement for bumping technology using solder resist
A semiconductor device is made by disposing a film layer over a substrate having first conductive layer. An opening is formed in the film layer to expose the first conductive layer. A second conductive layer is formed over the first conductive layer. A first bump is formed over the second conductive layer which promotes reflow of the first bump at a eutectic temperature. A standoff bump is formed on the film layer around a perimeter of the substrate. The film layer prevents reflow of the standoff bump at the eutectic temperature. A second bump is disposed between a semiconductor die and the first bump. The second bump is reflowed to electrically connect the semiconductor die to the first bump. After reflow of the second bump, the standoff bump has a height at least 70% of the second bump prior to reflow to maintain separation between the semiconductor die and substrate.
1. A method of making a semiconductor device, comprising:
providing a substrate having a conductive layer;
disposing a solder resist film laminate layer over the substrate and conductive layer;
forming an opening in the solder resist film laminate layer to expose the conductive layer;
curing the solder resist film laminate layer after the opening is formed;
forming an under bump metallization (UBM) layer over the conductive layer;
forming a plurality of first solder bumps over the UBM layer to promote reflow of the first solder bumps at a eutectic temperature;
forming a plurality of standoff solder bumps on the solder resist film laminate layer around a perimeter of the substrate, the solder resist film laminate layer preventing reflow of the standoff solder bumps at the eutectic temperature;
providing a semiconductor die;
disposing a plurality of second solder bumps between the semiconductor die and the first solder bumps of the substrate; and
reflowing the second solder bumps to electrically connect the semiconductor die to the first solder bumps of the substrate, wherein after reflow of the second solder bumps the standoff solder bumps have a height 70-90% of a height of the second solder bumps prior to reflow to maintain a predetermined separation between the semiconductor die and substrate.
2. The method of claim 1 , wherein the solder resist film laminate layer includes a photosensitive resin film or liquid-phase curable resin.
3. The method of claim 2 , wherein the photosensitive resin film includes butadiene polymer, photo-crosslinking agent, photo-sensitizer, photo-polymerization initiator, and storage stabilizer.
4. The method of claim 2 , wherein the liquid-phase curable resin includes bisphenol type epoxy resin, phenol type epoxy resin, or cresol type epoxy resin.
5. The method of claim 4 , further including:
mixing the liquid-phase curable resin with a catalyst, filler, and defoaming agent; and
curing by heat or ultraviolet radiation.
6. The method of claim 1 , wherein the first solder bumps and standoff solder bumps each include a eutectic solder material.
7. A method of making a semiconductor device, comprising:
providing a substrate having a first conductive layer;
disposing a film layer over the substrate and first conductive layer;
forming an opening in the film layer to expose the first conductive layer;
forming a second conductive layer over the first conductive layer;
forming a first bump over the second conductive layer which promotes reflow of the first bump at a eutectic temperature;
forming a standoff bump on the film layer around a perimeter of the substrate, the film layer preventing reflow of the standoff bump at the eutectic temperature;
providing a semiconductor die;
disposing a second bump between the semiconductor die and the first bump of the substrate; and
reflowing the second bump to electrically connect the semiconductor die to the first bump of the substrate, wherein after reflow of the second bump the standoff bump has a height at least 70% of a height of the second bump prior to reflow to maintain separation between the semiconductor die and substrate.
8. The method of claim 7 , further including curing the film layer after the opening is formed.
9. The method of claim 7 , wherein the film layer includes a photosensitive resin film or liquid-phase curable resin.
10. The method of claim 9 , wherein the photosensitive resin film includes butadiene polymer, photo-crosslinking agent, photo-sensitizer, photo-polymerization initiator, and storage stabilizer.
11. The method of claim 9 , wherein the liquid-phase curable resin includes bisphenol type epoxy resin, phenol type epoxy resin, or cresol type epoxy resin.
12. The method of claim 11 , further including:
mixing the liquid-phase curable resin with a catalyst, filler, and defoaming agent; and
curing by heat or ultraviolet radiation.
13. The method of claim 7 , wherein the first bump and standoff bump each include a eutectic solder material.
14. The method of claim 7 , wherein the semiconductor die is a flip chip type semiconductor die.
15. A method of making a semiconductor device, comprising:
providing a substrate having a first conductive layer;
disposing a film layer over the substrate and first conductive layer;
forming an opening in the film layer to expose the first conductive layer;
forming a second conductive layer over the first conductive layer;
forming a first bump over the second conductive layer which promotes reflow of the first bump at a eutectic temperature;
forming a standoff bump on the film layer around a perimeter of the substrate, the film layer preventing reflow of the standoff bump at the eutectic temperature to maintain a height of the standoff bump;
providing a semiconductor die;
disposing a second bump between the semiconductor die and the first bump of the substrate; and
reflowing the second bump to electrically connect the semiconductor die to the first bump of the substrate, wherein after reflow of the second bump the standoff bump has a height at least 70% of a height of the second bump prior to reflow to maintain separation between the semiconductor die and substrate.
16. The method of claim 15 , further including curing the film layer after forming the opening.
17. The method of claim 15 , wherein the film layer includes a photosensitive resin film or liquid-phase curable resin.
18. The method of claim 17 , wherein the photosensitive resin film includes butadiene polymer, photo-crosslinking agent, photo-sensitizer, photo-polymerization initiator, and storage stabilizer.
19. The method of claim 17 , wherein the liquid-phase curable resin includes bisphenol type epoxy resin, phenol type epoxy resin, or cresol type epoxy resin.
20. The method of claim 19 , further including:
mixing the liquid-phase curable resin with a catalyst, filler, and defoaming agent; and
curing by heat or ultraviolet radiation.
21. The method of claim 15 , wherein the first bump and standoff bump each include a eutectic solder material.