Method of manufacturing semiconductor device

Abstract

A method of manufacturing a semiconductor device includes a bonding step of bonding a chip on a wiring board by means of a bonding layer, and a wire bonding step of bonding a wire to a pad on the chip while applying ultrasonic vibration after the bonding step. A material having an elastic modulus of 100 MPa or higher at a process temperature in the wire bonding step is used as the bonding layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a wiring board showing the entire appearance of the wiring board;

FIG. 2 is a plan view of the wiring board;

FIG. 3 is a sectional view of the wiring board;

FIG. 4 is an enlarged sectional view of an essential portion of the wiring board shown in FIG. 3;

FIG. 5 is a plan view showing the process of manufacturing a semiconductor device according to an embodiment of the present invention;

FIG. 6 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 7 is an enlarged sectional view of an essential portion of the semiconductor device shown in FIG. 6;

FIG. 8 is a plan view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 9 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 10 is a sectional view showing a wire bonding step;

FIG. 11 is a plan view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 12 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 13 is a plan view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 14 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 15 is a plan view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 16 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 17 is a sectional view showing the process of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 18 is an enlarged sectional view of an essential portion of the semiconductor device shown in FIG. 17; and

FIG. 19 is a plan view showing a wiring board in which the proportion of portions where Cu wiring exists in the surface area for bonding of the chip is 90% or more.

Claims

1. A method of manufacturing a semiconductor device comprising; a bonding step of bonding a chip on a wiring board by means of a bonding layer; anda wire bonding step of bonding a wire to a pad on the chip while applying ultrasonic vibration after the bonding step,wherein a material having an elastic modulus of 100 MPa or higher at a process temperature in the wire bonding step is used as the bonding layer.

2. The method according to claim 1, wherein the chip used has a chip size of a 3 mm square or smaller.

3. The method according to claim 1, wherein the shorter side of the chip used has a length of 3 mm or less.

4. The method according to claim 1, wherein the chip used has an area of 9 mm2 or less.

5. The method according to claim 1, wherein the process temperature in the wire bonding step is set to 100° C. or higher.

6. The method according to claim 1, wherein the process temperature in the wire bonding step is set to 150° C. or higher.

7. The method according to claim 1, further comprising a resin encapsulation step of performing resin encapsulation on the wiring board by transfer molding after the wire bonding step.

8. The method according to claim 7, wherein in the resin encapsulation step the pressure at the time of resin encapsulation is 8 MPa or higher.

9. The method according to claim 1, wherein a film is used as the bonding layer.

10. The method according to claim 9, wherein the distance between ends of the chip and wiring on the wiring board is 0.5 mm or less.

11. The method according to claim 9, wherein the chip used has a thickness of 100 μm or less.

12. The method according to claim 9, further comprising a step of, after attaching the bonding layer to a back surface of a wafer on which a plurality of the chips are formed, cutting the wafer between each adjacent pair of the chips.

13. The method according to claim 9, wherein a material containing 10 wt % or more of an inorganic filler is used as the bonding layer.

14. The method according to claim 9, wherein a material containing 50 wt % or more of an inorganic filler is used as the bonding layer.

15. The method according to claim 1, wherein a wiring board in which the proportion of portions where wiring exists in the surface area for bonding of the chip is 90% or more is used as the wiring board.

16. The method according to claim 1, wherein a wiring board in which the height/depth of protrusions/recesses in the surface is 2 μm or less is used as the wiring board.

17. The method according to claim 1, wherein a wiring board in which the height/depth of protrusions/recesses in the surface is 10 μm or less is used as the wiring board.

18. The method according to claim 1, further comprising a resin encapsulation step of performing resin encapsulation on the wiring board by transfer molding after the wire bonding stepwherein a material having an elastic modulus of 1 GPa or less at the process temperature in the transfer molding is used as the bonding layer.