Lead frame and method for manufacturing the same

Abstract

To provide a lead frame and a method for manufacturing the same that can simplify an assembly process of a semiconductor device.SOLUTION: A lead frame 10 for a semiconductor device comprises: a lead frame body 11 having a first surface 11a and a second surface 11b on the opposite side of the first surface 11a; and a first resin part 17 arranged on the lead frame body 11. The lead frame body 11 has a first area A1, a second area A2, and a third area A3 arranged in order along a surface direction of the first surface 11a and the second surface 11b. The first area A1 is reduced in thickness from a side of the first surface 11a, the second area A2 is not reduced in thickness, and the third area A3 is reduced in thickness from the side of the first surface 11a and a side of the second surface 11b. The first resin part 17 is located on the side of the first surface 11a in the third area A3, and the depth D1 of the thickness reduced from the side of the first surface 11a in the first area A1 is deeper than the depth D3a of the thickness reduced from the side of the first surface 11a in the third area A3.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a lead frame and a method for manufacturing the same. [Background technology]

[0002] In recent years, some semiconductor devices used in electrical equipment for large currents have semiconductor elements mounted on lead frames (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-68783 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a semiconductor device, the leads are electrically connected to pads of the semiconductor chip via a metal plate and a bonding material.

[0005] The present disclosure provides a lead frame and a manufacturing method thereof that can simplify the assembly process of a semiconductor device. [Means for solving the problem]

[0006] The embodiments of the present disclosure relate to the following [1] to

[11] .

[0007] [1] A lead frame for a semiconductor device, comprising: a lead frame body having a first surface and a second surface opposite to the first surface; and a first resin portion arranged on the lead frame body, wherein the lead frame body has a first region, a second region, and a third region arranged in that order along the surface direction of the first surface and the second surface, wherein the first region is thinned from the first surface side, the second region is not thinned, the third region is thinned from the first surface side and the second surface side, the first resin portion is located on the first surface side of the third region, and the depth of thinning of the first region from the first surface side is deeper than the depth of thinning of the third region from the first surface side.

[0008] [2] The lead frame described in [1], wherein the lead frame body has a fourth region located between the second region and the third region, and the fourth region is thinned from the second surface side and not thinned from the first surface side.

[0009] [3] The lead frame body has a fifth region located on the opposite side of the second region from the third region, and the fifth region is thinned from the second surface side and not thinned from the first surface side. [1] The lead frame described in [2].

[0010] [4] The lead frame body has a sixth region located between the first region and the second region, the sixth region being thinned from the first surface side and not thinned from the second surface side, and a second resin portion being located in the sixth region. [1] A lead frame described in any one of [1] to [3].

[0011] [5] A lead frame as described in [4], wherein the depth of the sixth region thinned from the first surface side is shallower than the depth of the first region thinned from the first surface side.

[0012] [6] The lead frame according to [4] or [5], wherein the first resin portion and the second resin portion are integrated with each other.

[0013] [7] A lead frame described in any one of [4] to [6], wherein the thickness of the first resin portion is thicker than the depth to which the third region is thinned from the first surface side, and the thickness of the second resin portion is thicker than the depth to which the sixth region is thinned from the first surface side.

[0014] [8] A method for manufacturing a lead frame for a semiconductor device, comprising the steps of: preparing a metal substrate having a first surface and a second surface; etching the metal substrate from the first surface side to thin regions corresponding to the first and third regions of the lead frame body without thinning a region corresponding to the second region of the lead frame body; forming a mask layer in the region of the metal substrate corresponding to the first region; forming a first resin part in the third region of the metal substrate that is not covered by the mask layer; removing the mask layer; and etching the metal substrate from the first surface side to further thin the first region of the lead frame body and thin the third region from the second surface side.

[0015] [9] The method for manufacturing a lead frame according to [8], further comprising a step of polishing the first resin portion from the first surface side by a predetermined thickness.

[0016]

[10] A method for manufacturing a lead frame described in [8] or [9], wherein in the process of thinning the regions corresponding to the first region and the third region of the lead frame body, a sixth region located between the first region and the second region is thinned from the first surface side.

[0017]

[11] The method for manufacturing a lead frame according to

[10] , wherein in the step of forming a first resin portion in the third region, a second resin portion is formed in the sixth region. [Effects of the Invention]

[0018] According to the present disclosure, the assembly process of a semiconductor device can be simplified. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view showing a lead frame according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing the lead frame according to the first embodiment (a cross-sectional view taken along line II-II in FIG. 1). [Figure 3] FIG. 3 is a cross-sectional view showing the semiconductor device according to the first embodiment. [Figure 4] 4(a) to 4(h) are cross-sectional views showing a method for manufacturing a lead frame according to the first embodiment. [Figure 5] 5(a) to 5(d) are cross-sectional views showing a method for manufacturing a semiconductor device according to the first embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing a lead frame according to a second embodiment. [Figure 7] 7(a) to 7(h) are cross-sectional views showing a method for manufacturing a lead frame according to a second embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a lead frame according to a third embodiment. [Figure 9] 9(a) to 9(g) are cross-sectional views showing a method for manufacturing a lead frame according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] (First embodiment) The first embodiment will be described with reference to Figures 1 to 5. In the following figures, the same parts are denoted by the same reference numerals, and some detailed descriptions may be omitted.

[0021] In this specification, the X direction refers to the direction in which the first region A1 to the fifth region A5 are arranged. The X direction may be a direction parallel to one side of the lead frame 10 in a plan view. The Y direction is a direction perpendicular to both the X direction and the Z direction. The Y direction may be a direction perpendicular to the side of the lead frame 10 in a plan view. The Z direction refers to a direction parallel to the thickness direction of the lead frame 10. The X direction, Y direction, and Z direction are perpendicular to one another.

[0022] In this specification, half-etching refers to etching a material to be etched partway in its thickness direction. The thickness of the material to be etched after half-etching is, for example, 30% to 70%, preferably 40% to 60%, of the thickness of the material to be etched before half-etching.

[0023] (Lead frame configuration) An outline of a lead frame for a semiconductor device according to this embodiment will be described with reference to Figures 1 and 2. Figures 1 and 2 are diagrams showing the lead frame according to this embodiment.

[0024] 1 and 2 is used when manufacturing a semiconductor device 20 (FIG. 3). The lead frame 10 includes a lead frame body 11 and a first resin portion 17. The first resin portion 17 is disposed on the lead frame body 11.

[0025] The lead frame body 11 has a first surface 11a and a second surface 11b. The second surface 11b is located opposite the first surface 11a. The first surface 11a is the surface facing the opposite side to the surface to which the semiconductor element 21, described later, is bonded. The first surface 11a may be the surface facing outward from the semiconductor device 20. The first surface 11a may also be referred to as the "front surface" or "upper surface." The second surface 11b is the surface to which the semiconductor element 21, described later, is bonded. The second surface 11b may also be referred to as the "rear surface" or "lower surface."

[0026] The lead frame body 11 has a first region A1, a second region A2, a fourth region A4, a third region A3, and a fifth region A5. The first region A1, the second region A2, the fourth region A4, the third region A3, and the fifth region A5 are arranged in this order along the surface direction (X direction) of the first surface 11a and the second surface 11b.

[0027] 1, the first region A1 to the fifth region A5 of the lead frame body 11 each extend in a direction (Y direction) perpendicular to the direction in which the first region A1 to the fifth region A5 are arranged (X direction). The first region A1 to the fifth region A5 each have a rectangular shape in a plan view. The first resin portion 17 extends in a direction (Y direction) perpendicular to the direction in which the first region A1 to the fifth region A5 are arranged (X direction). The first resin portion 17 has a rectangular shape in a plan view.

[0028] The first area A1 to the fifth area A5 of the lead frame body 11 will be further described.

[0029] The first region A1 is thinned from the first surface 11a side. The first region A1 is not thinned from the second surface 11b side. A sealing resin 23 (described later) may be disposed on the first surface 11a side of the first region A1. No resin portion, such as the first resin portion 17, is provided in the first region A1. The end of the first region A1 opposite the second region A2 (the end on the negative side in the X direction) is exposed to the outside of the semiconductor device 20. This exposed portion may form an external terminal of the lead frame 10. A curved surface 11c is formed on the end of the first region A1 on the second region A2 side (the end on the positive side in the X direction). The thickness T1 of the first region A1 may be 15% to 70% of the maximum thickness T0 of the lead frame main body 11. The depth D1 of the thinning of the first region A1 from the first surface 11a side may be 30% to 85% of the maximum thickness T0 of the lead frame main body 11.

[0030] The second region A2 is directly adjacent to the first region A1. The second region A2 is not thinned from either the first surface 11a or the second surface 11b. The second region A2 may serve as a reference when adjusting the position of the lead frame 10 in the thickness direction. The second region A2 may also serve as a portion for dissipating heat from the semiconductor element 21. The second region A2 has a pair of side surfaces 11d and 11e. One side surface 11d is located on the first surface 11a side and faces the first region A1 side (the negative side in the X direction). The other side surface 11e is located on the second surface 11b side and faces the fourth region A4 side (the positive side in the X direction). Each of the pair of side surfaces 11d and 11e is exposed to the outside. The thickness T2 of the second region A2 is the same as the maximum thickness T0 of the lead frame body 11.

[0031] The fourth region A4 is directly adjacent to the second region A2. The fourth region A4 is thinned from the second surface 11b side. No resin portion such as the first resin portion 17 is provided in the fourth region A4. A side surface 11f is located on the first surface 11a side of the fourth region A4. The side surface 11f faces the third region A3 (the positive side in the X direction). The side surface 11f is in close contact with the first resin portion 17. A curved surface 11g is formed at the end of the fourth region A4 on the second region A2 side (the negative end in the X direction). The thickness T4 of the fourth region A4 may be 50% to 85% of the maximum thickness T0 of the lead frame main body 11. The depth D4 of the thinned fourth region A4 from the second surface 11b side may be 15% to 50% of the maximum thickness T0 of the lead frame main body 11.

[0032] The third region A3 is directly adjacent to the fourth region A4. The third region A3 is thinned from both the first surface 11a side and the second surface 11b side. The third region A3 is filled with a first resin portion 17. The surface of the third region A3 on the first surface 11a side is covered with the first resin portion 17. A curved surface 11h is formed at the end of the third region A3 on the fourth region A4 side (the end on the negative side in the X direction). A curved surface 11i is formed at the end of the third region A3 on the fifth region A5 side (the end on the positive side in the X direction). The thickness T3 of the third region A3 may be 15% to 50% of the maximum thickness T0 of the lead frame main body 11. A depth D3a of the thinned portion of the third region A3 from the first surface 11a side may be 20% to 70% of the maximum thickness T0 of the lead frame main body 11. A depth D3b of the third region A3 thinned from the second surface 11b side may be 10% or more and 30% or less of the maximum thickness T0 of the lead frame body 11. The surface of the third region A3 on the second surface 11b side (negative side in the Z direction) may form an internal terminal of the lead frame 10.

[0033] The fifth region A5 is directly adjacent to the third region A3. The fifth region A5 is thinned from the second surface 11b side. The fifth region A5 may be thinned from the second surface 11b side to the same extent as the third region A3 and the fourth region A4. Furthermore, the depth D5 of the fifth region A5 thinned from the second surface 11b side may be the same as the depth D3b of the third region A3 thinned from the second surface 11b side and the depth D4 of the fourth region A4 thinned from the second surface 11b side. However, the depth D5 may be different from the depths D3b and D4. The fifth region A5 is not thinned from the first surface 11a side. The fifth region A5 may serve as a reference for adjusting the position of the lead frame 10 in the thickness direction. The fifth region A5 may also serve as a region for dissipating heat from the semiconductor element 21. The semiconductor element 21, described below, may be disposed on the second surface 11b side of the fifth region A5. The fifth region A5 has a side surface 11j. The side surface 11j faces the third region A3 (the negative side in the X direction). The side surface 11j is in close contact with the first resin portion 17. The thickness T5 of the fifth region A5 may be 50% or more and 90% or less of the maximum thickness T0 of the lead frame body 11.

[0034] Next, the relationship between the thicknesses of the first region A1 to the fifth region A5 will be described.

[0035] The thickness T1 of the first region A1 is thicker than the thickness T3 of the third region A3. The thickness T4 of the fourth region A4 is thicker than the thickness T1 of the first region A1 and the thickness T3 of the third region A3. The thickness T5 of the fifth region A5 is the same as the thickness T4 of the fourth region A4, but may be different from the thickness T5 of the fifth region A5. The thickness T2 of the second region A2 is the same as the maximum thickness T0 of the lead frame body 11, and may be the thickest within the lead frame body 11.

[0036] Putting all of the above together, the following relationship holds: Note that the magnitude relationship between the values ​​before and after the symbol "," does not matter. T3 <T1<T4<T2,T5 Although the above relationship holds in the embodiment shown in FIG. 2, the magnitude relationship between T3, T1, and T4 does not necessarily have to be as described above.

[0037] Next, the relationship between the depths of the thinned portions of the first region A1 and the third region A3 will be described.

[0038] The depth D1 of the first region A1 thinned from the first surface 11a side is deeper than the depth D3a of the third region A3 thinned from the first surface 11a side. The depth D1 of the first region A1 thinned from the first surface 11a side is deeper than the depth D3b of the third region A3 thinned from the second surface 11b side. The depth D3a of the third region A3 thinned from the first surface 11a side is deeper than the depth D3b of the third region A3 thinned from the second surface 11b side.

[0039] Putting all of the above together, the following relationship holds: D3b <D3a<D1 Although the above relationship holds in the embodiment shown in FIG. 2, the magnitude relationship between D3b and D3a does not necessarily have to be as described above.

[0040] The lead frame body 11 may be entirely made of metal. In this case, examples of the metal constituting the lead frame body 11 include copper, copper alloy, 42 alloy (Ni42% Fe alloy), stainless steel, nickel alloy, and Invar material. The maximum thickness T0 of the lead frame body 11 may be 0.1 mm or more and 0.5 mm or less.

[0041] The first resin portion 17 is located on the third region A3. The first resin portion 17 is fixed to the first surface 11a side (positive side in the Z direction) of the third region A3. The first surface 11a side (positive side in the Z direction) of the first resin portion 17 is flush with the first surface 11a of the lead frame body 11. The first resin portion 17 has a pair of curved portions 17a, 17b. The curved portions 17a, 17b are on the second surface 11b side (negative side in the Z direction) of the first resin portion 17. One curved portion 17a is in close contact with the curved surface 11h. The other curved portion 17b is in close contact with the curved surface 11i. The thickness T8 of the first resin portion 17 is equal to the depth D3a of the thinning from the first surface 11a side of the third region A3 (T8 = D3a). Furthermore, the maximum thickness T0 of the lead frame body 11 is the sum of the thickness T8 of the first resin portion 17, the thickness T3 of the third region A3, and the depth D3b of the third region A3 thinned from the second surface 11b side (T0=T8+T3+D3b). By filling the third region A3 with the first resin portion 17 in advance, it is no longer necessary to wrap the sealing resin 23 around the third region A3.

[0042] The first resin portion 17 is a member made of resin. In this case, the resin material constituting the first resin portion 17 may be a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as a PPS resin.

[0043] (Configuration of semiconductor device) Next, a semiconductor device fabricated using the lead frame 10 according to this embodiment will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing the semiconductor device according to this embodiment.

[0044] 3 is a power semiconductor device used in, for example, electrical equipment for large currents. As shown in FIG. 3, the semiconductor device 20 includes a lead frame 10, a semiconductor element 21, a metal member 22, and a sealing resin 23.

[0045] The semiconductor element 21 is mounted on a metal member 22. The semiconductor element 21 has a plurality of electrodes on both its front side (the lead frame 10 side) and its back side (the metal member 22 side). The semiconductor element 21 may be any of various semiconductor elements that have been conventionally used, and is not particularly limited. The semiconductor element 21 may be a power element. The semiconductor element 21 may also be an integrated circuit such as a MOSFET.

[0046] The metal member 22 is fixed to the semiconductor element 21 via a first bonding layer 24. The first bonding layer 24 may be a conductive adhesive layer such as silver paste. The metal member 22 is electrically connected to an electrode on the back surface side of the semiconductor element 21 via the first bonding layer 24. The metal member 22 electrically connects the semiconductor element 21 to an external wiring board (not shown). The metal member 22 may be made of a metal material with good conductivity, such as copper or aluminum.

[0047] The sealing resin 23 seals the lead frame 10, the semiconductor element 21, and the metal member 22. A thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as a PPS resin, can be used as the sealing resin 23. The sealing resin 23 seals the lead frame 10 and the metal member 22 in a state where the second surface 11b side of the lead frame 10 and the back side of the metal member 22 (the side opposite the semiconductor element 21) are exposed to the outside.

[0048] The lead frame 10 is fixed to the semiconductor element 21 via a second bonding layer 25. The second bonding layer 25 may be a conductive adhesive layer such as silver paste. The lead frame 10 is electrically connected to an electrode on the back side of the semiconductor element 21 via the second bonding layer 25. The lead frame 10 electrically connects the semiconductor element 21 to an external wiring board (not shown). Other than this, the configuration of the lead frame 10 is the same as that shown in FIGS. 1 and 2 above, so a detailed description will be omitted here.

[0049] (Lead frame manufacturing method) Next, a method for manufacturing the lead frame 10 shown in Figures 1 and 2 will be described with reference to Figures 4(a) to 4(h). Figures 4(a) to 4(h) are cross-sectional views (figures corresponding to Figure 2) showing the method for manufacturing the lead frame 10 according to this embodiment.

[0050] First, as shown in FIG. 4(a), a flat metal substrate 31 is prepared. The metal substrate 31 has a first surface 31a and a second surface 31b. The first surface 31a and the second surface 31b of the metal substrate 31 correspond to the first surface 11a and the second surface 11b of the lead frame body 11, respectively. The metal substrate 31 may be made of a metal such as copper, a copper alloy, or a 42 alloy (a 42% Ni-Fe alloy). It is preferable to use a metal substrate 31 whose both surfaces have been degreased and cleaned.

[0051] Next, photosensitive resist is applied to the entire first surface 31a and second surface 31b of the metal substrate 31, respectively, and dried. Subsequently, the photosensitive resist on the metal substrate 31 is exposed to light through a photomask and developed. This forms etching resist layers 32 and 33 (FIG. 4(b)). The etching resist layer 32 on the first surface 31a side has openings 32b. The etching resist layer 33 on the second surface 31b side has openings 33b. Note that dry film resist, for example, may be used as the etching resist layers 32 and 33. At this time, the openings 32b of the etching resist layer 32 are formed in regions corresponding to the first region A1 and third region A3 of the lead frame body 11.

[0052] Next, a protective layer 37 is formed on the etching resist layer 33 on the second surface 31b side of the metal substrate 31. The protective layer 37 may be formed over the entire second surface 31b of the metal substrate 31. The protective layer 37 is also formed in the openings 33b of the etching resist layer 33. The protective layer 37 may be masking tape or a new etching resist layer. The protective layer 37 serves as a corrosion-resistant film during the etching process described below. Furthermore, the protective layer 37 serves as a buffer material when forming the mask layer 38 described below, thereby suppressing deformation of the metal substrate 31 and preventing scratches on the metal substrate 31. The provision of the protective layer 37 can suppress the occurrence of unevenness on the second surface 31b side when forming the mask layer 38.

[0053] Next, the metal substrate 31 is subjected to a first etching process (FIG. 4(c)). Specifically, the metal substrate 31 is etched with an etchant using the etching resist layers 32, 33 and the protective layer 37 as corrosion-resistant films. The etchant can be selected appropriately depending on the material of the metal substrate 31 used. For example, when copper is used as the metal substrate 31, a ferric chloride aqueous solution is usually used as the etchant, and spray etching may be performed on both sides of the metal substrate 31. As a result, the metal substrate 31 is partially thinned from the first surface 31a side by half etching. Specifically, the regions of the metal substrate 31 corresponding to the first region A1 and the third region A3 of the lead frame body 11 are thinned. The regions of the metal substrate 31 corresponding to the second region A2, the fourth region A4, and the fifth region A5 of the lead frame body 11 are not thinned and maintain the original thickness of the metal substrate 31.

[0054] At this time, the depth D1c of the region corresponding to the first region A1 thinned from the first surface 31a side is shallower than the depth D1 of the first region A1 of the completed lead frame body 11 thinned from the first surface 11a side (D1c < D1). On the other hand, the depth D3c of the region corresponding to the third region A3 thinned from the first surface 11a side is substantially the same as the depth D3 of the third region A3 of the completed lead frame body 11 (D3c = D3). Note that the depth D1c may be the same as the depth D3c.

[0055] Next, a mask layer 38 is formed on the etching resist layer 32 on the first surface 31a side of the metal substrate 31 (FIG. 4(d)).

[0056] The mask layer 38 is selectively formed in the regions of the metal substrate 31 corresponding to the first region A1 and the second region A2 of the lead frame body 11. The mask layer 38 is not formed in the regions of the metal substrate 31 corresponding to the fourth region A4, the third region A3, and the fifth region A5 of the lead frame body 11. The mask layer 38 may be formed by a printing method or a patterning method. Alternatively, a metal mask or a mesh mask may be used as the mask layer 38.

[0057] Next, a first resin portion 17 is formed in the regions of the metal substrate 31 not covered by the mask layer 38 (FIG. 4(d)). The first resin portion 17 is formed in the region corresponding to the third region A3 of the lead frame body 11. The first resin portion 17 may be formed in the regions corresponding to the fourth region A4 and the fifth region A of the lead frame body 11. The first resin portion 17 is not formed in the regions covered by the mask layer 38. That is, the first resin portion 17 is not formed in the regions corresponding to the first region A1 and the second region A2 of the lead frame body 11. The first resin portion 17 may be formed on the first surface 31a side of the metal substrate 31 by, for example, an inkjet method or a screen printing method using a thermosetting resin or a thermoplastic resin. At this time, the first resin portion 17 is filled in the recess corresponding to the third region A3. The first resin portion 17 may partially cover or entirely cover the etching resist layer 32 on the first surface 31a side.

[0058] Next, the mask layer 38 is removed from the first surface 31a side of the metal substrate 31 (FIG. 4(e)). As a result, the area on the first surface 31a side corresponding to the first region A1 of the lead frame body 11 is exposed to the outside. In addition, the protective layer 37 is removed from the second surface 31b side of the metal substrate 31. As a result, the areas on the second surface 31b side corresponding to the fourth region A4, the third region A3, and the fifth region A5 of the lead frame body 11 are exposed to the outside.

[0059] Next, the metal substrate 31 is subjected to a second etching process (FIG. 4(f)). Specifically, the metal substrate 31 is etched with an etchant using the first resin portion 17 and the etching resist layers 32 and 33 as corrosion-resistant films. The etchant may be the same as that used in the first etching process (FIG. 4(c)). As a result, the metal substrate 31 is thinned from the second surface 31b side and further thinned from the first surface 31a side. Specifically, regions of the metal substrate 31 corresponding to the fourth region A4, the third region A3, and the fifth region A5 of the lead frame body 11 are thinned from the second surface 31b. Furthermore, the region of the metal substrate 31 corresponding to the first region A1 of the lead frame body 11 is further thinned from the first surface 31a side. At this time, the depth of thinning from the first surface 11a side of the region corresponding to the first region A1 of the lead frame body 11 is substantially the same as the depth D1.

[0060] At this time, a metal portion 31c of the metal substrate 31 located at the end of the first region A1 on the opposite side (negative side in the X direction) from the second region A2 is removed. This thins the entire first region A1 from the first surface 11a side. The metal portion 31c may be left by appropriately widening the width of the etching resist layer 32. In this case, the metal portion 31c may be used as a connection portion for mounting the lead frame 10 to an external wiring board.

[0061] Next, the first resin portion 17 is polished from the first surface 31a side by a predetermined thickness (FIG. 4(g)). This positions the surface of the first resin portion 17 (the surface on the positive side in the Z direction) on the same plane as the first surface 31a (FIG. 4(g)). Specifically, the first resin portion 17 is polished from the positive side in the Z direction, and polishing of the first resin portion 17 is completed when the surface of the first resin portion 17 is on the same plane as the first surface 31a. The etching resist layer 32 may be removed simultaneously with polishing. The first resin portion 17 may be polished by a method similar to back grinding (also known as back grinding) for finishing semiconductor elements to a predetermined thickness or roll contact polishing used in the manufacture of printed circuit boards, for example.

[0062] Thereafter, the etching resist layer 33 on the second surface 31b side is removed. In this manner, the lead frame 10 shown in FIGS. 1 and 2 is obtained (FIG. 4(h)).

[0063] (Method of manufacturing a semiconductor device) Next, a method for manufacturing the semiconductor device 20 shown in FIG. 3 will be described with reference to FIGS. 5(a) to 5(d).

[0064] First, the metal member 22 is prepared (FIG. 5(a)).

[0065] Next, the semiconductor element 21 is mounted on the metal member 22. In this case, the semiconductor element 21 is placed and fixed on the metal member 22 using a first bonding layer 24 such as silver paste (die attach process) (FIG. 5(b)). At this time, the metal member 22 is electrically connected to the electrode on the back surface side of the semiconductor element 21 via the first bonding layer 24.

[0066] Next, a lead frame 10 is prepared, for example, by the method shown in FIGS. 4(a)-(h). Next, the lead frame 10 is mounted on a semiconductor element 21. In this case, the lead frame 10 is placed and fixed on the semiconductor element 21 using a second bonding layer 25 such as silver paste (FIG. 5(c)). At this time, the portion of the lead frame body 11 in the third region A3 that is thinned from the second surface 11b side is electrically connected to the electrode on the front surface of the semiconductor element 21 via the second bonding layer 25. The semiconductor element 21 is located in the fourth region A4 of the lead frame body 11, spaced apart from the curved surface 11g located on the second surface 11b side. The area where this curved surface 11g is located can accommodate an excess portion of the second bonding layer 25. Alternatively, the semiconductor element 21 may be located so as to be in close contact with the curved surface 11g of the lead frame body 11. This allows the adhesive distance between the second bonding layer 25 and the semiconductor element 21 to be maintained and the thickness of the second bonding layer 25 to be controlled.

[0067] Next, the metal member 22, the semiconductor element 21, and the lead frame 10 are subjected to injection molding or transfer molding with, for example, a thermosetting resin or a thermoplastic resin to form the sealing resin 23 (FIG. 5(d)). The sealing resin 23 is formed in the first region A1 of the lead frame 10, around the semiconductor element 21. The sealing resin 23 is also formed on the second surface 11b side of the lead frame main body 11. The sealing resin 23 does not have to be formed on the first surface 11a side of the lead frame main body 11. In this way, the metal member 22, the semiconductor element 21, and the lead frame 10 are sealed.

[0068] In this way, the semiconductor device 20 shown in FIG. 3 is obtained (FIG. 5(d)).

[0069] According to this embodiment, the lead frame 10 includes a lead frame body 11 and a first resin portion 17 disposed on the lead frame body 11. In this case, the lead frame 10, in which the lead frame body 11 and the first resin portion 17 are integrated with each other, can be disposed on the surface of the semiconductor element 21. This eliminates the need to sequentially attach leads, a metal plate, a bonding material, and the like to the surface of the semiconductor element 21 during the assembly process of the semiconductor device 20. This simplifies the assembly process of the semiconductor device 20. Furthermore, there is no electrical junction between the internal terminals (portions in contact with the second bonding layer 25) and the external terminals (portions extending outward from the sealing resin 23) of the lead frame 10. This prevents an increase in electrical resistance at the electrical junction.

[0070] Furthermore, according to this embodiment, the depth D1 of the first region A1 thinned from the first surface 11a side is deeper than the depth D3a of the third region A3 thinned from the first surface 11a side. This allows the thickness T1 of the first region A1 of the lead frame body 11 to be thin. Furthermore, when forming the sealing resin 23, the molten resin can easily flow into the first region A1. As a result, the semiconductor device 20 can be manufactured with high quality.

[0071] Furthermore, according to this embodiment, the third region A3 is thinned from both the first surface 11a side and the second surface 11b side. This allows the semiconductor element 21 to be accommodated on the second surface 11b side of the third region A3, thereby reducing the overall thickness of the semiconductor device 20. Heat from the semiconductor element 21 can also be more easily released by appropriately adjusting the width (distance in the X direction) of the third region A3 and widening the widths (distance in the X direction) of the fourth region A4 and the fifth region A5.

[0072] Furthermore, according to this embodiment, the second region A2 is not thinned, which allows the second region A2 to be exposed to the outside of the semiconductor device 20, and allows heat from the semiconductor element 21 to be released through the second region A2.

[0073] Furthermore, according to this embodiment, the first resin portion 17 is formed in advance in the third region A3. Therefore, it is not necessary to fill the third region A3 with the sealing resin 23. This makes it possible to prevent the sealing resin 23 from not being filled into the third region A3, which is difficult for the molten resin to reach when the sealing resin 23 is formed.

[0074] Furthermore, according to this embodiment, the lead frame body 11 has a fourth region A4 located between the second region A2 and the third region A3, and the fourth region A4 is thinned from the second surface 11b side but not from the first surface 11a side, which prevents a decrease in strength of the fourth region A4 during the manufacturing of the lead frame 10.

[0075] Furthermore, according to this embodiment, the lead frame body 11 has a fifth region A5 located on the opposite side of the second region A2 with respect to the third region A3, and the fifth region A5 is thinned from the second surface 11b side but not from the first surface 11a side. This allows the fifth region A5 to be exposed to the outside of the semiconductor device 20, and heat from the semiconductor element 21 can be dissipated through the fifth region A5. Furthermore, the semiconductor element 21 can be accommodated on the second surface 11b side of the fifth region A5, thereby reducing the overall thickness of the semiconductor device 20.

[0076] (Second embodiment) Next, a second embodiment will be described with reference to Figures 6 and 7. Figures 6 and 7 are diagrams showing the second embodiment. The second embodiment shown in Figures 6 and 7 differs mainly in that a sixth region A6 exists between the first region A1 and the second region A2, and the second resin portion 18 is located on the sixth region A6, but other configurations are substantially the same as those of the first embodiment described above. In Figures 6 and 7, the same parts as those in the first embodiment shown in Figures 1 to 5 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0077] (Lead frame configuration) 6, the lead frame 10 according to the present embodiment includes a lead frame body 11, a first resin portion 17, and a second resin portion 18. The first resin portion 17 and the second resin portion 18 are disposed on the lead frame body 11.

[0078] The lead frame body 11 has a first region A1, a sixth region A6, a second region A2, a fourth region A4, a third region A3, and a fifth region A5. The first region A1, the sixth region A6, the second region A2, the fourth region A4, the third region A3, and the fifth region A5 are arranged in this order along the surface direction (X direction) of the first surface 11a and the second surface 11b.

[0079] The sixth region A6 is located between the first region A1 and the second region A2. The sixth region A6 is thinned from the first surface 11a side. The sixth region A6 is not thinned from the second surface 11b side. The second resin portion 18 is located in the sixth region A6. The surface of the sixth region A6 on the first surface 11a side (the surface on the positive side in the Z direction) is covered with the second resin portion 18. A step portion 11k is formed on the first region A1 side of the sixth region A6. The thickness T6 of the sixth region A6 may be 30% or more and 80% or less of the maximum thickness T0 of the lead frame main body 11. The depth D6 of the thinned portion of the sixth region A6 from the first surface 11a side may be 20% or more and 70% or less of the maximum thickness T0 of the lead frame main body 11.

[0080] The thickness T6 of the sixth region A6 may be greater than the thickness T1 of the first region A1. The thickness T6 of the sixth region A6 may be greater than the thickness T3 of the third region A3.

[0081] In this embodiment, the following relationships hold for the thicknesses of the first region A1 to the sixth region A6: Note that the magnitude relationship between the values ​​before and after the symbol "," does not matter. T3 <T1<T6<T4<T2,T5 Although the above relationship holds in the embodiment shown in FIG. 6, the magnitude relationship between T3, T1, T6, and T4 does not necessarily have to be as described above.

[0082] The depth D6 of the sixth region A6 reduced from the first surface 11a side is shallower than the depth D1 of the first region A1 reduced from the first surface 11a side. The depth D6 of the sixth region A6 reduced from the first surface 11a side may be the same as or different from the depth D3a of the third region A3 reduced from the first surface 11a side.

[0083] In this embodiment, the following relationship holds for the depths of the thinned portions of the first region A1, the sixth region A6, and the third region A3. Note that the magnitude relationship between the values ​​before and after the symbol "," does not matter. D3b <D3a,D6<D1 Although the above relationship holds in the embodiment shown in FIG. 6, the magnitude relationship between D3b and D3a does not necessarily have to be as described above.

[0084] In addition, the configurations of the first area A1 to the fifth area A5 may be the same as those in the first embodiment.

[0085] The second resin portion 18 is located on the sixth region A6. The second resin portion 18 is fixed to the first surface 11a side (positive side in the Z direction) of the sixth region A6. The surface of the second resin portion 18 on the first surface 11a side (positive side in the Z direction) is flush with the first surface 11a of the lead frame body 11. The second resin portion 18 has a pair of curved portions 18a, 18b. One curved portion 18a is located on the first region A1 side (negative side in the X direction). One curved portion 18a is located closer to the first surface 11a than the step portion 11k. A portion of the second resin portion 18 may protrude onto the first region A1. The other curved portion 18b is in close contact with the curved surface 11c. A thickness T9 of the second resin portion 18 is equal to a depth D6 of the thinning from the first surface 11a side of the sixth region A6 (T9 = D6). Furthermore, the maximum thickness T0 of the lead frame body 11 is the sum of the thickness T9 of the second resin portion 18 and the thickness T6 of the sixth region A6 (T0 = T9 + T6). In this embodiment, the thickness T9 of the second resin portion 18 is the same as the depth D6 of the sixth region A6 thinned from the first surface 11a side (T9 = D6). By filling the sixth region A6 with the second resin portion 18 in advance, it is not necessary to wrap the sealing resin 23 around the sixth region A6.

[0086] The second resin portion 18 may be made of the same material as the first resin portion 17 .

[0087] (Lead frame manufacturing method) Next, a method for manufacturing the lead frame 10 shown in Fig. 6 will be described with reference to Figs. 7(a) to (h). Figs. 7(a) to (h) are cross-sectional views showing the method for manufacturing the lead frame 10 according to this embodiment.

[0088] First, a flat metal substrate 31 is prepared in substantially the same manner as in the step shown in FIG. 4(a) (FIG. 7(a)).

[0089] Next, etching resist layers 32 and 33 are formed on the metal substrate 31 (FIG. 7(b)) in substantially the same manner as the step shown in FIG. 4(b). At this time, openings 32b of the etching resist layer 32 are formed in regions corresponding to the first region A1, the sixth region A6, and the third region A3 of the lead frame body 11. Next, a protective layer 37 is formed on the etching resist layer 33 on the second surface 31b side of the metal substrate 31.

[0090] Next, the metal substrate 31 is subjected to a first etching process (FIG. 7(c)) in substantially the same manner as the process shown in FIG. 4(c), thereby thinning the areas of the metal substrate 31 corresponding to the first area A1, the sixth area A6, and the third area A3 of the lead frame body 11.

[0091] At this time, the depth D1c of the region corresponding to the first region A1 thinned from the first surface 31a side is shallower than the depth D1 of the first region A1 of the completed lead frame body 11 thinned from the first surface 11a side (D1c < D1). The depth D6c of the region corresponding to the sixth region A6 thinned from the first surface 31a side is substantially the same as the depth D6 of the sixth region A6 of the completed lead frame body 11 (D6c = D6). Also, the depth D3c of the region corresponding to the third region A3 thinned from the first surface 31a side is substantially the same as the depth D3 of the third region A3 of the completed lead frame body 11 (D3c = D3). Note that the depths D1c, D6c, and D3c may be the same as each other.

[0092] Next, in substantially the same manner as the process shown in FIG. 4(d), a mask layer 38 is formed in the region of the metal substrate 31 corresponding to the first region A1 of the lead frame body 11 on the first surface 31a side (FIG. 7(d)).

[0093] The mask layer 38 is selectively formed in the region of the metal substrate 31 corresponding to the first region A1 of the lead frame body 11. The mask layer 38 is not formed in the regions of the metal substrate 31 corresponding to the sixth region A6, the second region A2, the fourth region A4, the third region A3, and the fifth region A5 of the lead frame body 11.

[0094] Next, substantially similar to the step shown in FIG. 4(d), the first resin portion 17 and the second resin portion 18 are integrally formed in the region of the metal substrate 31 that is not covered with the mask layer 38 (FIG. 7(d)). The first resin portion 17 is formed in a region corresponding to the fourth region A4 of the lead frame main body 11. The second resin portion 18 is formed in a region corresponding to the sixth region A6 of the lead frame main body 11. The first resin portion 17 and the second resin portion 18 may also be formed in regions corresponding to the second region A2, the fourth region A4, the third region A3, and the fifth region A5 of the lead frame main body 11. The first resin portion 17 and the second resin portion 18 are connected to each other in regions corresponding to the second region A2 and the fourth region A4 of the lead frame main body 11. The first resin portion 17 is not formed in the region covered with the mask layer 38. That is, the first resin portion 17 is not formed in a region corresponding to the first region A1 of the lead frame main body 11.

[0095] Next, in substantially the same manner as in the process shown in FIG. 4(e), the mask layer 38 is removed from the first surface 31a side of the metal substrate 31, and the protective layer 37 is removed from the second surface 31b side of the metal substrate 31 (FIG. 7(e)).

[0096] Next, the metal substrate 31 is subjected to a second etching process (FIG. 7(f)) in a manner substantially similar to the process shown in FIG. 4(f). Specifically, the metal substrate 31 is etched with an etchant using the first resin portion 17, the second resin portion 18, and the etching resist layers 32 and 33 as corrosion-resistant films. The etchant may be the same as that used in the first etching process (FIG. 7(c)). As a result, the metal substrate 31 is thinned from the second surface 31b side and further thinned from the first surface 31a side. Specifically, the regions of the metal substrate 31 corresponding to the fourth region A4, the third region A3, and the fifth region A5 of the lead frame body 11 are thinned from the second surface 31b. Furthermore, the region of the metal substrate 31 corresponding to the first region A1 of the lead frame body 11 is further thinned from the first surface 31a side. At this time, the depth to which the area corresponding to the first region A1 of the lead frame body 11 is thinned from the first surface 11a side is substantially the same as the depth D1 to which the area corresponding to the first region A1 of the completed lead frame body 11 is thinned from the first surface 11a side.

[0097] At this time, metal portion 31c of metal substrate 31, which is located at the end of first region A1 and on the opposite side of second region A2 (negative side in the X direction), is removed. Also, metal portion 31d, which is located at the end of first region A1 and on the second region A2 side (positive side in the X direction), is removed. This thins the entire first region A1 from the first surface 11a side. Metal portion 31c may be left by appropriately widening the width of etching resist layer 32. In this case, metal portion 31c may be used as a connection portion for mounting lead frame 10 to an external wiring board.

[0098] Next, in substantially the same manner as the step shown in FIG. 4(g), the first resin portion 17 and the second resin portion 18 are polished to a predetermined thickness from the first surface 31a side (FIG. 7(g)). As a result, the surfaces (the surfaces on the positive side in the Z direction) of the first resin portion 17 and the second resin portion 18 are positioned on the same plane as the first surface 31a. At this time, the first resin portion 17 and the second resin portion 18 are separated from each other. The etching resist layer 32 may be removed simultaneously with the polishing.

[0099] Thereafter, the etching resist layer 33 on the second surface 31b side is removed in substantially the same manner as in the step shown in Fig. 4(h). In this manner, the lead frame 10 shown in Fig. 6 is obtained (Fig. 7(h)).

[0100] The configuration of a semiconductor device manufactured using lead frame 10 according to this embodiment may be substantially the same as the configuration of the semiconductor device according to the first embodiment (FIG. 3). A method for manufacturing a semiconductor device using lead frame 10 according to this embodiment may be substantially the same as the method for manufacturing lead frame 10 according to the first embodiment (FIGS. 5(a)-(d)).

[0101] According to this embodiment, the lead frame body 11 has a sixth region A6 located between the first region A1 and the second region A2, and the sixth region A6 is thinned from the first surface 11a side. The second resin portion 18 is located in the sixth region A6 of the lead frame body 11. By arranging the second resin portion 18 in the sixth region A6 in advance, when forming the sealing resin 23, it is not necessary to fill the sealing resin 23 into the sixth region A6, which is difficult for the molten resin to reach.

[0102] (Third embodiment) Next, a third embodiment will be described with reference to Figures 8 and 9. Figures 8 and 9 are diagrams showing the third embodiment. The third embodiment shown in Figures 8 and 9 differs mainly in that the first resin portion 17 and the second resin portion 18 are integrated, and other configurations are substantially the same as those of the second embodiment described above. In Figures 8 and 9, parts that are the same as those in the first embodiment shown in Figures 1 to 5 and the second embodiment shown in Figures 6 and 7 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0103] (Lead frame configuration) 8, the lead frame 10 according to the present embodiment includes a lead frame body 11, a first resin portion 17, and a second resin portion 18. The first resin portion 17 and the second resin portion 18 are disposed on the lead frame body 11. The first resin portion 17 and the second resin portion 18 are integrated with each other.

[0104] In this embodiment, the configurations of the first area A1 to the fifth area A5 may be the same as those in the first embodiment, and the configuration of the sixth area A6 may be the same as that in the second embodiment.

[0105] The first resin portion 17 and the second resin portion 18 are integrated with each other via the third resin portion 19A. The third resin portion 19A is located on the first surface 11a side of the second region A2 and the fourth region A4. The fourth resin portion 19B is located on the first surface 11a side of the fifth region A5. The fourth resin portion 19B is integrated with the second resin portion 18. The surfaces (surfaces on the positive side in the Z direction) of the first resin portion 17, the second resin portion 18, the third resin portion 19A, and the fourth resin portion 19B are located on the same plane. The surfaces (surfaces on the positive side in the Z direction) of the first resin portion 17, the second resin portion 18, the third resin portion 19A, and the fourth resin portion 19B are located on the positive side in the Z direction of the first surface 11a.

[0106] The thickness T8 of the first resin portion 17 is thicker than the depth D3a of the thinning from the first surface 11a side of the third region A3 (T8>D3a). The thickness T9 of the second resin portion 18 is thicker than the depth D6 of the thinning from the first surface 11a side of the sixth region A6 (T9>D6). The thickness T8 of the first resin portion 17 may be equal to the thickness T9 of the second resin portion 18.

[0107] The maximum thickness T10 of the lead frame 10 is thicker than the maximum thickness T0 of the lead frame body 11 (T10>T0). The maximum thickness T10 of the lead frame 10 may be 105% or more and 200% or less of the maximum thickness T0 of the lead frame body 11.

[0108] (Lead frame manufacturing method) Next, a method for manufacturing the lead frame 10 shown in Fig. 8 will be described with reference to Figs. 9(a) to 9(g). Figs. 9(a) to 9(g) are cross-sectional views showing the method for manufacturing the lead frame 10 according to this embodiment.

[0109] First, a flat metal substrate 31 is prepared in substantially the same manner as in the step shown in FIG. 7(a) (FIG. 9(a)).

[0110] Next, in substantially the same manner as the step shown in Fig. 7(b), etching resist layers 32 and 33 are formed on the metal substrate 31 (Fig. 9(b)). Next, a protective layer 37 is formed on the etching resist layer 33 on the second surface 31b side of the metal substrate 31.

[0111] Next, the metal substrate 31 is subjected to a first etching process (FIG. 9(c)) in substantially the same manner as the process shown in FIG. 7(c), thereby thinning the areas of the metal substrate 31 corresponding to the first area A1, the sixth area A6, and the third area A3 of the lead frame body 11.

[0112] Next, the etching resist layer 32 on the first surface 31a side is removed, leaving the etching resist layer 33 on the second surface 31b side.

[0113] Next, a mask layer 38 is formed on the first surface 31a of the metal substrate 31 (FIG. 9(d)) in substantially the same manner as the step shown in FIG. 7(d). The mask layer 38 is selectively formed on the metal substrate 31 in a region corresponding to the first region A1 of the lead frame body 11.

[0114] Next, in substantially the same manner as in the step shown in FIG. 7(d), the first resin portion 17 and the second resin portion 18 are integrally formed in the area of ​​the metal substrate 31 that is not covered by the mask layer 38 (FIG. 9(d)).

[0115] Next, in substantially the same manner as in the process shown in FIG. 7(e), the mask layer 38 is removed from the first surface 31a side of the metal substrate 31, and the protective layer 37 is removed from the second surface 31b side of the metal substrate 31 (FIG. 9(e)).

[0116] Subsequently, a second etching process is performed on the metal substrate 31 in substantially the same manner as the process shown in Fig. 7(f) (Fig. 9(f)). As a result, the metal substrate 31 is thinned from the second surface 31b side and further thinned from the first surface 31a side.

[0117] Thereafter, the etching resist layer 33 on the second surface 31b side is removed, thereby obtaining the lead frame 10 shown in FIG. 8 (FIG. 9(g)).

[0118] In the present embodiment, there is no step of polishing the first resin portion 17 and the second resin portion 18. However, the present invention is not limited to this, and the first resin portion 17 and the second resin portion 18 may be polished to an extent that does not reach the first surface 31a of the metal substrate 31, thereby flattening the first resin portion 17 and the second resin portion 18.

[0119] The configuration of a semiconductor device manufactured using lead frame 10 according to this embodiment may be substantially the same as the configuration of the semiconductor device according to the first embodiment (FIG. 3). A method for manufacturing a semiconductor device using lead frame 10 according to this embodiment may be substantially the same as the method for manufacturing lead frame 10 according to the first embodiment (FIGS. 5(a)-(d)).

[0120] According to this embodiment, the thickness T8 of the first resin portion 17 is thicker than the depth D3a of the thinning from the first surface 11a side of the third region A3 (T8>D3a). Furthermore, the thickness T9 of the second resin portion 18 is thicker than the depth D6 of the thinning from the first surface 11a side of the sixth region A6 (T9>D6). Therefore, when manufacturing the semiconductor device 20, by forming the sealing resin 23 so as to surround the first resin portion 17 and the second resin portion 18, the semiconductor device 20 can be obtained in which the metal surface of the lead frame body 11 is not exposed on the surface. This allows the first resin portion 17 and the second resin portion 18 to be utilized as part of the sealing resin of the semiconductor device 20.

[0121] It is also possible to combine the multiple components disclosed in the above embodiments and modifications as needed, or to delete some of the components disclosed in the above embodiments and modifications. [Explanation of symbols]

[0122] 10 Lead Frame 11 Lead frame body 11a 1st page 11b Side 2 17 First resin part 18 Second resin part 20 Semiconductor Devices 21 Semiconductor elements 22 Metallic parts 23 Sealing resin 24 1st bonding layer 25 Second bonding layer

Claims

1. In a lead frame for a semiconductor device, a lead frame body having a first surface and a second surface opposite the first surface; a first resin portion disposed on the lead frame body, the lead frame body has a first region, a second region, and a third region that are arranged in this order along a surface direction of the first surface and the second surface, The first region is thinned from the first surface side, the second region is not thinned; the third region is thinned from the first surface side and the second surface side, the first resin portion is located on the first surface side of the third region, A lead frame, wherein a depth of the first region thinned from the first surface side is greater than a depth of the third region thinned from the first surface side.

2. the lead frame body has a fourth region located between the second region and the third region; The lead frame according to claim 1 , wherein the fourth region is thinned from the second surface side and is not thinned from the first surface side.

3. the lead frame body has a fifth region located on the opposite side of the second region with respect to the third region; The lead frame according to claim 1 , wherein the fifth region is thinned from the second surface side and is not thinned from the first surface side.

4. the lead frame body has a sixth region located between the first region and the second region, the sixth region is thinned from the first surface side and is not thinned from the second surface side, The lead frame according to claim 1 , wherein a second resin portion is located in the sixth region.

5. The lead frame according to claim 4 , wherein a depth of the sixth region thinned from the first surface side is shallower than a depth of the first region thinned from the first surface side.

6. The lead frame according to claim 4 , wherein the first resin portion and the second resin portion are integrated with each other.

7. The lead frame of claim 4, wherein the thickness of the first resin portion is thicker than the depth to which the third region is thinned from the first surface side, and the thickness of the second resin portion is thicker than the depth to which the sixth region is thinned from the first surface side.

8. 1. A method of manufacturing a lead frame for a semiconductor device, comprising: providing a metal substrate having a first surface and a second surface; a step of thinning the regions corresponding to the first region and the third region of the lead frame body by etching the metal substrate from the first surface side, without thinning the region corresponding to the second region of the lead frame body; forming a mask layer on the metal substrate in a region corresponding to the first region; forming a first resin portion in the third region of the metal substrate that is not covered by the mask layer; removing the mask layer; A method for manufacturing a lead frame, comprising a step of etching the metal substrate from the first surface side to further thin the first region of the lead frame body and thin the third region from the second surface side.

9. The method for manufacturing a lead frame according to claim 8 , further comprising the step of polishing the first resin portion from the first surface side by a predetermined thickness.

10. 9. A method for manufacturing a lead frame as described in claim 8, wherein in the process of thinning the regions corresponding to the first region and the third region of the lead frame body, a sixth region located between the first region and the second region is thinned from the first surface side.

11. The method for manufacturing a lead frame according to claim 10 , wherein in the step of forming a first resin portion in the third region, a second resin portion is formed in the sixth region.

Images