Leadframe semiconductor integrated circuit device using the same, and method of and process for fabricating the two

Abstract

In order to improve the package body cracking resistance of an LSI package at the reflow soldering and to provide both a leadframe suitable for fabricating the LSI package according to the flexible manufacturing system and an LSI using the leadframe, the adhered area between a semiconductor chip 2 and a resin is enlarged by making the external size of a die pad 3 smaller than that of the semiconductor chip to be mounted thereon. Moreover, a variety of semiconductor chips 2 having different external sizes can be mounted on the die pad 3 by cutting the leading ends of leads 5 to a suitable length in accordance with the external sizes of the semiconductor chips 2.

Description

Face face being directed upward so that the burrs 11 may be left on the back opposed to the chip mounting face.

On the other hand, the inner lead portions 5a are reluctant, if the burrs 11 are left at the lower side at a wire bonding step, to have wires bonded thereto so that the bonding is defective. When the inner lead portions 5a are to be pressed, the pressing is carried out downward with the bonding face being directed downward, to leave the burrs 11 on the wire bonding face.

Next, as shown in FIG. 4, the wire bonding regions 32 of the inner lead portions 5a are plated with Ag. In the leadframe 1 of the present embodiment, as will be described hereinafter, the area of the regions to be plated with Ag is made larger than that of the leadframe of the prior art so that the leading ends of the leads 5 to be used may be cut to a predetermined length in accordance with the external size of the semiconductor chip 2 to be mounted on the die pad 3. In the case of the prior art, for example, the distance from the leading ends of the inner leads could be within a range of about 1 mm while considering the wire bonding errors and the errors at the plating time. In the present invention, however, the distance has to be no less than 1 mm and 1.5 to 2 mm or more if the first cut and the second cut are considered.

Next, the leadframe 1 is subjected to a down-setting step. This down-setting step is a treatment to lower the height of the die pad 3 than that of the leads 5, as viewed horizontally, by bending the midway portions (as indicated at S in FIG. 5) of the suspension leads 4 downward while using a press mold 12, as shown in FIG. 5. Specifically, if the chip mounting face of the die pad 3 and the wire bonding face of the inner lead portions 5a are assumed a first face and if the face opposed to the first face is assumed a second face, the first face is positioned at the side of the second face rather than the first face of the inner lead portions 5a.

FIG. 6 is a top plan view showing the leadframe 1 which has been subjected to the down-setting treatment. For example, the distance from the center of the die pad 3 to the down-set position (S) of each suspension lead 4 is about 8.5 to 9.0 mm, and the depth of the down-set (i.e., the height from the principal face of the die pad 3 to the principal face of the leads 5) is about 0.2 mm.

Thanks to the aforementioned down-setting treatment, the resin thickness is substantially equalized at the upper face side of the semiconductor chip 2 and at the lower face side of the die pad 3 when a package is to be molded by fitting up a mold with the leadframe 1 having the semiconductor chip 2.

Next, the tape 6 is adhered to both the midway portions (i.e., wider portions) of the suspension leads 4 for supporting the die pad 3 and the inner lead portions 5a.

The adhesion of the tape 6 is carried out, as shown in FIG. 7, by positioning the tape 6 on the leadframe 1 placed on a heat stage 13 and by pushing a tool 14 downward.

For example, the tape 6 is constructed such that an adhesive 6b of an acrylic resin is applied to a thickness of about 0.02 mm onto one side of a film 6a of a polyimide resin having an external size of about 18.5 mm×18.5 mm, a width of about 1.5 mm and a thickness of about 0.05 mm.

FIG. 8 is a top plan view showing the leadframe 1 having the tape 6 adhered thereto; FIG. 9 is a section taken along line IX-IX of FIG. 9; and FIG. 10 is a section taken along line X-X of FIG. 8. In order to retain the adhesion area of the tape 6, the suspension leads 4 are made wider at their midway portions (i.e., the widened portions of the suspension leads 4) than at other portions, as shown in FIG. 8.

When the leadframe 1 having the semiconductor chip 2 is attached to the mold to form the package body, the die pad 3 can be prevented, by adhering the tape 6, i.e., the insulating film to the midway portions of the suspension leads 4 to fix the die pad 3, from being fluctuated by the flow of the molten resin. As a result, the flow velocities of the molten resin can be equalized at the upper face side of the semiconductor chip 2 and the lower face side of the die pad 3 to prevent the molding defect such as through voids.

Since the leadframe 1 of the present embodiment thus achieved is constructed such that the area of the chip mounting face of the die pad 3 is smaller than that of either the principal face of the semiconductor chip 2 to be mounted thereon or the back face opposed to the aforementioned principal face, it can mount semiconductor chips having different external sizes thereon. By cutting the leading ends of the leads 5 to shorten them, moreover, it is possible to mount a semiconductor chip 2a or 2b having a larger area.

FIG. 11(a) is a top plan view showing a leadframe 1a in which the leading ends of the leads 5 are cut so as to mount the semiconductor chip 2a having a larger area than that of the semiconductor chip shown by double-dotted lines in FIG. 1, and FIG. 11(b) is a section taken along line XI-XI of FIG. 11(a). Broken lines appearing in FIG. 11(a) indicate the positions of the leading ends of the leads 5 before cut. FIG. 12 is a top plan view showing a leadframe 1b which has its leads 5 further cut at their leading ends. In this case, it is possible to mount the semiconductor chip 2b having a larger area than that of the semiconductor chip 2a.

Thus, in case the die pad 3 has a diameter of about 3 mm, for example, it is possible to mount a variety of semiconductor chips having external sizes ranging from about 5 mm×5 mm to about 15 mm×15 mm. The cutting step of the leads 5 is carried out by means of a press but with the wire bonding region being directed downward, so as to prevent the plated Ag layer from peeling from the wire bonding regions 32. As shown in FIG. 11(b), therefore, the molding is made with the leading ends of the inner lead portions 5a being directed upward.

Next, one embodiment of a process for fabricating a QFP by using the aforementioned leadframe 1 will be described with reference to FIGS. 13 to 30.

First of all, as shown in FIG. 13, an adhesive 15 for adhering the semiconductor chip 2 is applied to the die pad 3 of the leadframe 1. Incidentally, FIG. 13 shows the leadframe 1 in which the leads 5 have their leading ends uncut. In case, however, the wider semiconductor chip 2a or 2b is to be mounted, the leading ends of the leads 5 are cut in advance to a predetermined length prior to the step of applying the adhesive 15 to the die pad 3. In short, the leadframe 1a or 1b is formed in advance. The cutting of the leading ends is carried out by considering that the leading ends of the inner leads 5a is positioned at a position at such a distance (e.g., 0.5 mm) or more apart from the outer periphery of a chip to be mounted as is kept away from being connected with that outer periphery.

The application of the adhesive 15 is carried out, as shown in FIG. 14, by dropping the adhesive 15 onto the die pad 3 of the leadframe 1 placed on a stage 16, by means of a dispenser 17. The adhesive 15 is prepared by mixing Ag powder into a thermoset epoxy resin, for example. Incidentally, reference numerals 18 and 19 appearing in FIG. 14 designate a nozzle and a syringe, respectively. The die pad 3 may be sized to allow the adhesive 15 to be applied thereto.

Since the die pad 3 of the aforementioned leadframe 1 has a small area, the adhesive 15 may be applied to one point of the principal face of the die pad 3. This application results in such an advantage over the existing leadframe having a larger die pad that the structure of the nozzle 18 used may be simpler and that the application time of the adhesive 15 may be shorter.

As shown in FIG. 15, moreover, slightly wider small pads (or adhesion-applied portions) 20 than the suspension leads 4 may be formed around the die pad 3 so that the adhesive 1S 15 may be applied to the individual principal faces of the die pad 3 and the small pads 20.

Since a sufficient adhesion strength is thus achieved, it is possible to prevent a disadvantage that the semiconductor chip 2 rotationally goes out of position over the die pad 3. Thanks to the formation of the small pads (i.e., adhesion-applied portions) 20, moreover, the rigidity of the suspension leads 4 can be substantially enhanced to prevent the die pad 3 from being fluctuated by the flow of the molten resin when the package is to be prepared by fitting up the mold with the leadframe 1 having the semiconductor chip 2 mounted thereon.

The aforementioned small pads 20 may be formed midway of the individual suspension leads 4, namely, between the die pads 3 and the midway portions S, as shown in FIG. 16. Effects similar to the aforementioned ones can be achieved in this modification, too.

Next, as shown in FIG. 17, the semiconductor chip 2 is positioned over the die pad 3 having the adhesive 15 applied thereto, by means of a collet 21. For example, the semiconductor chip 2 is made of single crystal silicon having an external size of about 5.34 mm×5.34 mm and a thickness of about 0.4 mm.

FIG. 18 is a top plan view showing the leadframe 1 in which the suspension leads 4 supporting the die pad 3 is partially formed with V-shaped grooves 22. These V-shaped grooves 22 are used as graduations for positioning the semiconductor chip 2 accurately on the die pad 3 and are formed at a constant interval in the principal Faces of the suspension leads 4, as shown in an enlarged section in FIG. 19.

When the semiconductor chip 2 is to be positioned over the die pad 3, the locations of the V-shaped grooves 22 are detected from above the leadframe 1 by means of a (not-shown) camera, as shown in FIGS. 20(a) to 20(c). In accordance with these data, the semiconductor chips 2 having the various external sizes are moved to accurate positions.

As shown in FIG. 21, on the other hand, a plurality of projections 23 may be formed at a constant interval midway of the individual suspension leads 4, i.e., between the die pad 3 and the midway portions S so that they may be used as the graduations for positioning the semiconductor chip 2 on the die pad 3. These V-shaped grooves 22 or projections 23 can be used at a visual inspection seep after the semiconductor chip 2 have been positioned on the die pad 3.

Next, as shown in FIG. 22, the leadframe 1 having the semiconductor chip 2 positioned on the die pad 3 is heated on a heat stage 24 to set the adhesive 15. The heating conditions are at a 200° to 250° C. and for about 30 secs. to 1 min., for example. Incidentally, the setting of the adhesive 15 can also be carried out by means of an oven. FIG. 23 is a top plan view showing the leadframe 1 which has finished the step of mounting the semiconductor chip 2 on the die pad 3.

Next, as shown in FIGS. 24 to 28, the semiconductor chip 2 mounted on the die pad 3 has its bonding pads 25 bonded to the leads 5 by means of wires 28 of Au to connect them electrically. FIG. 25 is a section showing the connected relation between the inner lead 5a and the semiconductor chip 2, and FIG. 28 is a section showing the relation between the suspension lead 4 and the semiconductor chip 2.

As shown in FIG. 24, the leadframe 1 of the present embodiment is arranged with the leading ends of the leads 5 in the shape of letter “V” along the individual sides of the semiconductor chip 2 (such that the leads 5 are made longer in the vicinity of the corner portions of the semiconductor chip 2, namely, close to the suspension leads 4 and shorter in the vicinity of the central portions of the individual sides, namely, at a distance from the suspension leads 4). As a result, lengths of the wires 26 are substantially equalized between all the bonding pads 25 and the leads 5 so that they need not be changed to make the wire bonding work easy.

FIG. 27 is a top plan view showing the principal face of a heat stage of the wire bonding apparatus to be used in the present embodiment. This heat stage 27 is formed with relief grooves 28 in which are to be fitted the die pad 3 and the portions (i.e., the inner portions of the aforementioned down-set positions (S)) of the suspension leads 4 of the leadframe 1.

Since the heat stage 27 is formed in its principal face with the aforementioned relief grooves 28, either the leadframe 1 (as shown in FIG. 28(a)) having the large semiconductor chip 2b mounted on the die pad 3 or the leadframe 1 (as shown in FIG. 28(b)) having the small semiconductor chip 2 mounted can be wirebonded to eliminate the troubles of replacing the heat stage 27 each time the external sizes of the semiconductor chip 2 change. Incidentally, reference characters t₁ appearing in FIG. 28(a) indicate the thickness (e.g., about 0.15 mm in the present embodiment) of the leadframe 1, and characters t₂ indicate the amount of down-set (e.g., about 0.2 mm in the present embodiment) of the die pad 3. The wire length is about 1.0 to 5.0 mm, as taken in a linear distance, from the bonding pads to the bonding points of the inner lead portions 5a.

Next, the aforementioned leadframe 1 is fitted in the mold, and the semiconductor chip 2, the die pads 3, the inner lead portions 5a and the wires 26 are molded of an epoxy resin, as shown in FIGS. 29 and 30, into a package body 29. After this, the unnecessary portions of the leadframe 1, that is, the dam bar 7, the outer frame 8 and the inner frame 9 exposed to the outside of the package body 29 are cut away by means of a press. Finally, the leads 5 left at the outside of the package body 29 are shaped into a predetermined shape to complete a QFP type surface-mounting semiconductor device 30. Then, this QFP type surface-mounting semiconductor device 30 is mounted over a wiring substrate 34 by the fellow soldering method. Numeral 33 designates land pads for placing the leads 5 thereon, and numeral 36 designates the solder.

Since the QFP 30 thus fabricated by using the leadframe 1 of the present embodiment has its die pad made smaller than the semiconductor chip 2 mounted thereon, the peripheral portion of the semiconductor chip 2 has its back contacting closely to the sealing resin.

Since the adhesion of the interface between the sealing resin and the die pad 3 is sufficient, the interface can be suppressed from peeling even if it should be expanded by the moisture having invaded and been heated at the fellow soldering step. Thus, it is possible to provide the QFP 30 having an improved reflow cracking resistance.

Moreover, since the leadframe 1 of the present embodiment can mount a variety of semiconductor chips 2 of different external sizes, the troubles of preparing a leadframe for each of the semiconductor chips having different external sizes are eliminated. As a result, the leadframe 1 can be standardized to reduce its production cost thereby to provide the QFP 30 at a reasonable cost.

Still moreover, since the leadframe 1 of the present embodiment reduces the external size of the die pad 3, the amount of the adhesive 15 to be used for mounting the semiconductor chip 2 on the die pad 3 can also be reduced to provide the QFP 30 at a more reasonable cost.

Although our invention has been specifically described in connection with the embodiments thereof, it should not be limited to the foregoing embodiments but can naturally be modified in various manners without departing from the gist thereof.

The shape of the die pad should not be limited to the circle but may be another such as a rectangle, if the adhering strength of the chip to the die pad and the minimum application region of the adhesive are retained. As shown in FIG. 31, moreover, the package cracking resistance at the reflow soldering can be better improved by forming a through hole 31 in a portion of the die pad 3 having a smaller area than that of the semiconductor chip 2 to increase the adhesion area between the semiconductor chip 2 and the resin.

As shown in FIG. 32, still moreover, the intersections of the four suspension leads 4 may be widened to use this wide area as the die pad 3.

In the foregoing embodiments, the present invention has been described in case it is applied to the leadframe for fabricating the QFP, but can also be applied generally to the leadframes to be used for assembling the surface-mounting LSI package. The present invention can also be applied to a leadframe to be used for fabricating a pin-inserted LSI package such as DIP (i.e., Dual In-line Package).

The effects to be achieved by the representatives of the invention disclosed herein will be briefly summarized in the following:

(1) According to the present invention, it is possible to provide an LSI package having an improved reflow cracking resistance; and

(2) According to the present invention, a leadframe matching the flexible manufacturing system of the LSI package can be provided to reduce the production cost of the LSI package.

Claims

1. A semiconductor integrated circuit device comprising:

a semiconductor chip having a main surface including semiconductor elements and a plurality of bonding pads;

a leadframe having:

a chip mounting portion for mounting said semiconductor chip;

suspension leads unitarily formed with said chip mounting portion, a width of said chip mounting portion being wider than a width of each of said suspension leads,

a plurality of inner lead portions arranged to surround said semiconductor chip and being electrically connected with said bonding pads by bonding wires, and

a plurality of outer lead portions individually connected with said inner lead portions; and

a resin member sealing said semiconductor chip, said inner lead portions, said chip mounting portion, said suspension leads and said bonding wires;

wherein said chip mounting portion is smaller than said semiconductor chip and is positioned under a substantially central portion of said semiconductor chip, said semiconductor chip is fixed to said chip mounting portion by adhesive, said semiconductor chip is fixed to a part of each of said suspension leads by adhesive which is located under a peripheral portion of said semiconductor chip, and an adhesive region of said chip mounting portion and said semiconductor chip and an adhesive region of each of said suspension leads and said semiconductor chip are separated from each other and wherein said suspension leads and said chip mounting portion of said leadframe are continuously formed in an area of said semiconductor chip.

2. A semiconductor integrated circuit device according to claim 1, wherein each of said suspension leads includes a first portion and a second portion which is wider than said first portion, wherein said second portion is separated from said chip mounting portion and is positioned under said peripheral portion of said semiconductor chip, and wherein said semiconductor chip is fixed at said second portion of each of said suspension leads.

3. A semiconductor integrated circuit device according to claim 1, wherein said semiconductor chip is of a tetragonal shape.

4. A semiconductor integrated circuit device according to claim 1, wherein said semiconductor chip includes a rear surface opposing said main surface and is fixed to said chip mounting portion and said suspension leads at one portion of said rear surface, and wherein the other portion of said rear surface which is exposed from said chip mounting portion and said suspension leads is directly contacted to said resin member.

5. A semiconductor integrated circuit device according to claim 2, wherein said semiconductor chip is a rectangular shape and said suspension leads include four suspension leads, and wherein four corners of said rectangular-shaped semiconductor chip are supported by said four suspension leads.

6. A semiconductor integrated circuit device according to claim 5, wherein said resin member has a rectangular shape, and wherein said outer lead portions are extended outwardly from four sides of said rectangular-shaped resin member.

7. A semiconductor integrated circuit device according to claim 6, further comprising:

a plurality of grooves for positioning the semiconductor chip, said grooves each formed on said four suspension leads.

8. A semiconductor integrated circuit device according to claim 6, further comprising:

a plurality of projections for positioning the semiconductor chip, said projections each formed on said four suspension leads.

9. A semiconductor integrated circuit device according to claim 7, wherein said grooves are arranged on said four suspension leads so as to accord to four corners of said rectangular-shaped semiconductor chip.

10. A semiconductor integrated circuit device according to claim 8, wherein said projections are arranged on said four suspension leads so as to accord to four corners of said rectangular-shaped semiconductor chip.

11. A semiconductor integrated circuit device comprising:

a semiconductor chip having a main surface including semiconductor elements and a plurality of bonding pads;

a leadframe having:

a cracking suppression means for mounting said semiconductor chip thereon and for suppressing, during a reflow soldering processing, device cracking, wherein said cracking suppression means is a chip mounting portion which is smaller than said semiconductor chip and which is positioned under a substantially central portion of said semiconductor chip,

suspension leads unitarily formed with said chip mounting portion, a width of said chip mounting portion being wider than a width of each of said suspension leads,

a plurality of inner lead portions arranged to surround said semiconductor chip and being electrically connected with said bonding pads by bonding wires, and

a plurality of outer lead portions individually connected with said inner lead portions; and

a resin member sealing said semiconductor chip, said inner lead portions, said chip mounting portion, said suspension leads and said bonding wires;

wherein said semiconductor chip is fixed to said chip mounting portion by adhesive, said semiconductor chip is fixed to a part of each of said suspension leads by adhesive which is located under a peripheral portion of said semiconductor chip, and an adhesive region of said chip mounting portion and said semiconductor chip and an adhesive region of each of said suspension leads and said semiconductor chip are separated from each other and wherein said suspension leads and said chip mounting portion of said leadframe are continuously formed in an area of said semiconductor chip.

12. A semiconductor integrated circuit device according to claim 11, wherein said semiconductor chip includes a rear surface opposing said main surface and is fixed to said chip mounting portion and said suspension leads at one portion of said rear surface, and wherein the other portion of said rear surface which is exposed from said chip mounting portion and said suspension leads is directly contacted to said resin member.

13. A semiconductor integrated circuit device comprising:

a semiconductor chip having a main surface including semiconductor elements and a plurality of bonding pads;

a leadframe having:

a chip mounting portion for mounting said semiconductor chip,

suspension leads unitarily formed with said chip mounting portion, a width of said chip mounting portion being wider than a width of each of said suspension leads,

a plurality of inner lead portions arranged to surround said semiconductor chip and being electrically connected with said bonding pads by bonding wires, and

a plurality of outer lead portions individually connected with said inner lead portions; and

a resin member sealing said semiconductor chip, said inner lead portions, said chip mounting portion, said suspension leads and said bonding wires;

wherein said chip mounting portion is smaller than said semiconductor chip and is positioned under a substantially central portion of said semiconductor chip, said semiconductor chip is fixed to said chip mounting portion by adhesive, said semiconductor chip is fixed to a part of each of said suspension leads by adhesive which is located under a peripheral portion of said semiconductor chip, and an adhesive region of said chip mounting portion and said semiconductor chip and an adhesive region of each of said suspension leads and said semiconductor chip are separated from each other.

14. A semiconductor integrated circuit device comprising:

a semiconductor chip having a main surface including semiconductor elements and a plurality of bonding pads;

a leadframe having:

a cracking suppression means for mounting said semiconductor chip thereon and for suppressing, during a reflow soldering processing, device cracking, wherein said cracking suppression means is a chip mounting portion which is smaller than said semiconductor chip and which is positioned under a substantially central portion of said semiconductor chip,

suspension leads unitarily formed with said chip mounting portion, a width of said chip mounting portion being wider than a width of each of said suspension leads,

a plurality of inner lead portions arranged to surround said semiconductor chip and being electrically connected with said bonding pads by bonding wires, and

a plurality of outer lead portions individually connected with said inner lead portions; and

a resin member sealing said semiconductor chip, said inner lead portions, said chip mounting portion, said suspension leads and said bonding wires;

wherein said semiconductor chip is fixed to said chip mounting portion by adhesive, said semiconductor chip is fixed to a part of each of said suspension leads by adhesive which is located under a peripheral portion of said semiconductor chip, and an adhesive region of said chip mounting portion and said semiconductor chip and an adhesive region of each of said suspension leads and said semiconductor chip are separated from each other.

15. A semiconductor device comprising:

(a) a semiconductor chip having a plurality of semiconductor elements and bonding pads formed on a main surface thereof;

(b) a lead frame having:

a chip mounting portion having one surface for mounting said semiconductor chip;

suspension leads continuously formed with said chip mounting portion; and

a plurality of leads each having an inner lead portion and an outer lead portion continuously formed with said inner lead portion and being arranged at a periphery of said chip mounting portion, said inner lead portions of said plurality of leads being electrically connected with said bonding pads of said semiconductor chip; and

(c) a resin member sealing said semiconductor chip, said chip mounting portion and said inner lead portions of said plurality of leads,

wherein a size of said chip mounting portion is smaller than that of said semiconductor chip, and

wherein said one surface of said chip mounting portion is a surface on which burrs are not formed, during formation of said chip mounting portion,

wherein said chip mounting portion is positioned under a substantially central portion of said semiconductor chip,

wherein said semiconductor chip is fixed to said chip mounting portion by an adhesive,

wherein said semiconductor chip is fixed to a part of each of suspension leads by an adhesive, and

wherein said suspension leads and said chip mounting portion of said lead frame are continuously formed in an area of said semiconductor chip.

16. A semiconductor device according to claim 15, wherein said burrs are formed when said lead frame is made by pressing.

17. A semiconductor device according to claim 15, wherein said chip mounting portion has a substantially circular form in a plane view.

18. A semiconductor device according to claim 16, wherein said chip mounting portion has a substantially cross form in a plane view.

19. A semiconductor device according to claim 15, wherein said inner lead portions of said plurality of leads are electrically connected with said bonding pads of said semiconductor chip by a plurality of bonding wires.

20. A semiconductor device according to claim 19, wherein parts of said inner lead portions of said plurality of leads, to which said plurality of bonding wires are connected, are plated.

21. A semiconductor device comprising:

(a) a semiconductor chip having a plurality of semiconductor elements and bonding pads formed on a main surface thereof;

(b) a lead frame having:

a chip mounting portion for mounting said semiconductor chip;

suspension leads continuously formed with said chip mounting portion; and

a plurality of leads each having an inner lead portion and an outer lead portion continuously formed with said inner lead portion and being arranged at a periphery of said chip mounting portion,

(c) a plurality of bonding wires electrically connecting said inner lead portions of said plurality of leads with said bonding pads of said semiconductor chip respectively, each of said inner lead portions of said plurality of leads having one surface to which a corresponding bonding wire among said plurality of bonding wires is connected; and

(d) a resin member sealing said semiconductor chip, said plurality of bonding wires, said chip mounting portion and said inner lead portions of said plurality of leads,

wherein said one surface of said inner lead portion of each of said plurality of leads is a surface on which burrs are not formed, said burrs being resultant from formation of said plurality of leads,

wherein said chip mounting portion is positioned under a substantially central portion of said semiconductor chip,

wherein said semiconductor chip is fixed to said chip mounting portion by an adhesive,

wherein said semiconductor chip is fixed to a part of each of suspension leads by an adhesive, and

wherein said suspension leads and said chip mounting portion of said lead frame are continuously formed in an area of said semiconductor chip.

22. A semiconductor device according to claim 21, wherein a size of said chip mounting portion is smaller than that of said semiconductor chip.

23. A semiconductor device according to claim 21, wherein said burrs are formed when said lead frame is made by pressing.

24. A semiconductor device according to claim 22, wherein said chip mounting portion has a substantially circular form in a plane view.

25. A semiconductor device according to claim 22, wherein said chip mounting portion has a substantially cross form in a plane view.

26. A semiconductor device comprising:

(a) a semiconductor chip having a plurality of semiconductor elements and bonding pads formed on a main surface thereof;

(b) a lead frame having:

a chip mounting portion having a first surface for mounting said semiconductor chip;

suspension leads continuously formed with said chip mounting portion; and

a plurality of leads each having an inner lead portion and an outer lead portion continuously formed with said inner lead portion and being arranged at a periphery of said chip mounting portion;

(c) a plurality of bonding wires electrically connecting said inner lead portions of said plurality of leads with said bonding pads of said semiconductor chip respectively, each of said inner lead portions of said plurality of leads having a second surface to which a corresponding bonding wire among said plurality of bonding wires is connected; and

(d) a resin member sealing said semiconductor chip, said plurality of bonding wires, said chip mounting portion and said inner lead portions of said plurality of leads,

wherein a size of said chip mounting portion is smaller than that of said semiconductor chip,

wherein said first surface of said chip mounting portion is a surface on which burrs are not formed, and

wherein said second surface of said inner lead portion of each of said plurality of leads is a surface on which said burrs are formed, said burrs resultant from formation of said chip mounting portion and said plurality of leads,

wherein said chip mounting portion is positioned under a substantially central portion of said semiconductor chip,

wherein said semiconductor chip is fixed to said chip mounting portion by an adhesive,

wherein said semiconductor chip is fixed to a part of each of suspension leads by an adhesive, and

wherein said suspension leads and said chip mounting portion of said lead frame are continuously formed in an area of said semiconductor chip.