Dual lead frame semiconductor package and method of manufacture

Abstract

A semiconductor package and a method for making the same are provided. In the method, a clip is used to conduct a lead frame and at least one chip. The clip has at least one second connection segment, at least one third connection segment, and at least one intermediate connection segment. The second connection segment is electrically connected to a second conduction region of the chip and a second pin of the lead frame respectively, and the third connection segment is electrically connected to a third conduction region of the chip and a third pin of the lead frame respectively. The intermediate connection segment connects the at least one second connection segment and the at least one third connection segment, and is removed in a subsequent process. Thereby, the present invention does not need to use any gold wire, which effectively saves the material cost and the processing time.

Claims

1. A semiconductor package, comprising: a substrate lead frame configured for mounting a first face of an integrated circuit chip, and further configured to couple a plurality of electrical signals of said integrated circuit chip to an exterior of said semiconductor package; a clip lead frame comprising: a first clip lead portion configured to couple a first conductive region of said integrated circuit chip to a first portion of said substrate lead frame; and a second clip lead portion configured to couple a second conductive region of said integrated circuit chip to a second portion of said substrate lead frame, wherein said substrate lead frame comprises the same material as said clip lead frame.

2. The semiconductor package of claim 1, wherein the first and second conductive regions of said integrated circuit chip are on an opposite face of said integrated circuit chip from said first face.

3. The semiconductor package of claim 1, wherein each of said first and second portions of said clip lead frame are non-planar.

4. The semiconductor package of claim 1, wherein said clip lead frame comprises the same material as said substrate lead frame.

5. The semiconductor package of claim 1, wherein said clip lead frame is free of gold.

6. The semiconductor package of claim 1, wherein said semiconductor package is free of wire bonds.

7. The semiconductor package of claim 1, wherein said first clip lead portion is configured to couple to a source contact of said integrated circuit chip, and said second clip lead portion is configured to couple to a gate contact of said integrated circuit chip.

8. A semiconductor package comprising: an integrated circuit chip comprising first and second opposing faces, wherein said first face is electrically and mechanically coupled to a substrate lead frame, and wherein said substrate lead frame couples a plurality of electrical signals of said integrated circuit chip to an exterior of said semiconductor package; a clip lead frame comprising: a first clip lead portion coupling a first conductive region of said integrated circuit chip to a first portion of said substrate lead frame; and a second clip lead portion coupling a second conductive region of said integrated circuit chip to a second portion of said substrate lead frame, wherein said clip lead frame consists of metal.

9. The semiconductor package of claim 8, wherein the first and second conductive regions of said integrated circuit chip are on said second face of said integrated circuit chip.

10. The semiconductor package of claim 8, wherein said first portion of said clip lead frame is non-planar.

11. The semiconductor package of claim 8, wherein said clip lead frame comprises the same material as said substrate lead frame.

12. The semiconductor package of claim 8, wherein said clip lead frame is free of gold.

13. The semiconductor package of claim 8, wherein said semiconductor package is free of wire bonds.

14. The semiconductor package of claim 8, wherein said first clip lead portion is configured to couple to a source contact of said integrated circuit chip, and said second clip lead portion is configured to couple to a gate contact of said integrated circuit chip.

15. A clip lead frame comprising: a single contiguous piece of electrically conductive material comprising: a plurality of first clip lead portions configured to couple a first conductive region of an integrated circuit chip to a first portion of a substrate lead frame; a plurality of second clip lead portions configured to couple a second conductive region of said integrated circuit chip to a second portion of said substrate lead frame; and a plurality of clip lead frame extensions coupled to said plurality of first clip lead portions and further coupled to said plurality of second clip lead portions.

16. The clip lead frame of claim 15 wherein said clip lead frame is non-planar.

17. The clip lead frame of claim 15 comprising one or more larger physical areas for providing an area required by absorption.

18. The clip lead frame of claim 15 wherein each of said first clip lead portions comprises a first clip lead portion end configured for solder reflow bonding to said first conductive region.

19. The clip lead frame of claim 15 wherein each of said first clip lead portions comprises a second clip lead recess portion configured for solder reflow bonding to said substrate lead frame.

20. The clip lead frame of claim 15 wherein said clip lead frame is free of structures joining materials together.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the present technology are illustrated by way of example and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:

(2) FIGS. 1, 2 and 3 show a schematic view illustrating various stages of a method for making a semiconductor package, according to the conventional art.

(3) FIGS. 4 through 23 show a schematic view illustrating various stages of a method for making a semiconductor package, in accordance with one embodiment of the present technology.

DETAILED DESCRIPTION

(4) Reference will now be made in detail to the embodiments of the present technology, examples of which are illustrated in the accompanying drawings. While the present technology will be described in conjunction with these embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present technology, numerous specific details are set forth in order to provide a thorough understanding of the present technology. However, it is understood that the present technology may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present technology.

(5) In this application, the use of the disjunctive is intended to include the conjunctive. The use of definite or indefinite articles is not intended to indicate cardinality. In particular, a reference to the object or a object is intended to denote also one of a possible plurality of such objects. It is also to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

(6) Embodiments of the present technology are directed toward semiconductor packaging techniques. Referring now to FIG. 4, a stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 4 will be further explained with reference to FIG. 5, which is a partially enlarged view of FIG. 4. FIGS. 4 and 5 illustrate a substrate lead frame 400 including a frame portion 405 and a plurality of lead set 410, 420, 430 portions. For each set of leads, a first substrate lead 410 is coupled to the frame portion 405 by one or more extensions 415. A second substrate lead 420 and a third substrate lead 430 are coupled to the frame portion 405 by one or more respective extensions 425, 435. The second substrate lead 420 and third substrate lead 430 are separated by a space from the first substrate lead 410 along a first side 411 of the first substrate lead 410. In one implementation, the first substrate lead 410 is a first drain interconnect, the second substrate lead 420 is a first source interconnect, and the third substrate lead 430 is a first gate interconnect. In another implementation, the first substrate lead 410 is a first source interconnect, the second substrate lead 420 is a first drain interconnect, and the third substrate lead 430 is a first gate interconnect.

(7) Referring now to FIG. 6, another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 6 will be further explained with reference to FIG. 7, which is a partially enlarged view of FIG. 6. A first solder 510 is formed on the first substrate lead 410, a second solder 520 is formed on the second substrate lead 420, and a third solder 530 is formed on the third substrate lead 430.

(8) Referring now to FIG. 8, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 8 will be further explained with reference to FIG. 9, which is a partially enlarged view of FIG. 8. An integrated circuit (IC) chip 600 is disposed on the first substrate lead 410 of each set of leads of the substrate lead frame. In one implementation, the IC chip 600 is a power metal-oxide-semiconductor field-effect transistor (MOSFET). Each IC chip 600 has an upper surface 610 and a lower surface 640 (not shown in FIGS. 8 and 9). The lower surface has a first conductive region (not shown in FIGS. 8 and 9) disposed on the second solder 520 on the first substrate lead 410 of the substrate lead frame 400. The upper surface 610 of the IC chip 600 has a second conductive region 620 and a third conductive region 630. In the one implementation, the first conductive region is a drain conductive region, the second conductive region 620 is a source conductive region, and the third conductive region 630 is a gate conductive region. In the other implementation, the first conductive region is a source conductiveregion, the second conductive region 620 is a drain conductive region, and the third conductive region 630 is a gate conductive region.

(9) Referring now to FIG. 10, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 10 will be further explained with reference to FIG. 11, which is a partially enlarged view of FIG. 10. As illustrated in FIGS. 10 and 11, a fourth solder 540 is formed on the second conductive region 620 and a fifth solder 550 is formed on the third conductive region 630 of the IC chip 600.

(10) Referring now to FIG. 12, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 12 will be further explained with reference to FIGS. 13, 14 and 15. FIG. 13 is a partially enlarged view of FIG. 12. FIG. 14 is a cross-sectional view of FIG. 12 taken along line 14-14, and FIG. 15 is a cross-section view of FIG. 12 taken along line 15-15. FIGS. 12-15 illustrate a clip lead frame 700 including a frame portion 705 and a plurality of lead set 710, 720 portions. Each set of clip leads 710, 720 are coupled to the frame portion 705 by one or more respective extensions 730. In one implementation, the frame portion 705 includes one or more larger physical areas for providing an area required by absorption. In the one implementation, a first clip lead 710 is a second source interconnect, and a second clip lead 720 is a second gate interconnect. In the other implementation, the first clip lead 710 is a second drain interconnect, and the second clip lead 720 is a second gate interconnect.

(11) Each of the first clip leads 710 includes a first end 711, a second end 712, a first recess 713 and a second recess 714. Each of the second clip leads 720 includes a first end 721, a second end 722, a first recess 723, and a second recess 724.

(12) Referring now to FIG. 16, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. The stage illustrated in FIG. 16 will be further explained with reference to FIGS. 17 and 18. FIG. 17 is a partially enlarged view of FIG. 16. FIG. 18 is a cross-sectional view of FIG. 16 taken along line 18-18. FIGS. 16-18 illustrate assembly of the substrate lead frame 400, the IC chips 600, and the clip lead frame 700. The first clip lead 710 is disposed at the first recess 712 on the second solder 520 on the second substrate lead 420, and the second end 712 of the first clip lead 710 is disposed on the fourth solder 540 on the second conductive region 620 of the IC chip 600. The second clip lead 720 is disposed at the first recess 724 on the third solder 530 on the third substrate lead 430, and the second end 722 of the second clip lead 720 is disposed on the fifth solder 550 on the third conductive region 630 of the IC chip 600.

(13) A solder reflow process is performed to electrically and mechanically connect the clip leads 710, 720 of the clip lead frame 700, the IC chips 600 and the substrate leads 410, 420, 430 of the substrate lead frame 400 together. As a result, the first clip lead 710 is electrically and mechanically coupled at the first recess 712 to the second substrate lead 420, and the second end 712 of the first clip lead 710 is electrically and mechanically coupled to the second conductive region 620 of the IC chip 600. The second clip lead 720 at the first recess 724 is electrically and mechanically coupled to the third substrate lead 430, and the second end 722 of the second clip lead 720 is electrically and mechanically coupled to the third conductive region 630 of the IC chip 600.

(14) Referring now to FIG. 19, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. In FIG. 19 a molding process is performed. The substrate lead frame 400, the IC chips 600 and the clip lead frame 700 coupled together are placed in a mold cavity (riot shown), and then a molding compound 800 is filled in the mold cavity to encapsulate the substrate lead frame 400, the IC chips 600 and the clip lead frame 700. In one implementation, the first, second and third substrate leads 410, 420, 430 are exposed outside the molding compound 800.

(15) Referring now to FIGS. 20 and 21, yet another stage in the manufacture of a semiconductor package, in accordance with one embodiment of the present technology, is shown. As illustrated in FIG. 20, a cutting, process may be performed along first cutting lines L1. As illustrated in FIG. 21, an alternative cutting process may be performed along second cutting lines L2. Cutting along lines L1 or L2 separates the substrate leads 410, 420, 430 from the substrate frame 405 and from each other. Cutting along lines L1 or L2 also separates the clip leads 710, 720 from the clip frame 705 and from each other. However, the second substrate lead 420 remains electrically and mechanically coupled to the first clip lead 710 and the third substrate lead 430 remains electrically and mechanically coupled to the second clip lead 720.

(16) Referring now to FIGS. 22 and 23, yet another stage in the manufacture of a semiconductor package, in accordance with another embodiment of the present technology, is shown. FIG. 22 shows a top view of a semiconductor package 900 inside the molding compound. FIG. 23 shows a side sectional view of the semiconductor package 900. FIG. 22 illustrates the semiconductor package 900 including two IC chips 600 resulting from cutting along cut lines L2 in FIG. 21.

(17) The semiconductor package 900, in accordance with embodiments of the present invention includes one or more IC chips 600. A first conductive region on a first surface of a respective IC chip 600 is electrically and mechanically coupled to a first substrate lead 410. A first clip lead 710 is electrically and mechanically coupled between a second conductive region on the second surface of the respective IC chip 600 and a second substrate lead 420. A second clip lead 720 is electrically and mechanically coupled between a third conductive region on the second surface of the respective IC chip 600 and a third substrate lead 420. The one or more IC chips 600, the respective first, second and third substrate leads 410, 420, 430 and the first and second clip leads 710, 720 are encapsulated, except for package contact portions of the first, second and third substrate leads 410, 420, 430. In the one implementation, the first substrate lead 410 is a drain interconnect, the coupled together first clip lead 710 and second substrate lead 420 is a source interconnect, and the coupled together second clip lead 720 and third substrate lead 430 is a gate interconnect of the respective IC chip 600 within the package 900. In the other implementation, the first substrate lead 410 is a source interconnect, the coupled together first clip lead 710 and second substrate lead 420 is a drain interconnect, and the coupled together second clip lead 720 and third substrate lead 430 is a gate interconnect of the respective IC chip 600 within the package 900.

(18) Embodiments of the present technology are advantageously adaptable to manufacturing integrated circuit packages including one or more IC chips. Moreover, embodiments of the present technology do not utilize gold wires to may package interconnects, which effectively saves on material cost. In addition, the whole clip lead frame 700 of the present technology is integrally placed to effectively save processing time. The clip lead frame 700 may be fabricated through etching or other sophisticated techniques to narrow a space between the clip leads 710, 720, so that the clip lead frame 700 is applicable to IC chips 600 having a small size.

(19) The foregoing descriptions of specific embodiments of the present technology have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present technology and its practical application to thereby enable others skilled in the art to best utilize the present technology and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.