Method for manufacturing a processed product, method for manufacturing a semiconductor device, and manufacturing apparatus for a processed product

Abstract

To provide a manufacturing method of a workpiece capable of obtaining higher connection reliability when manufacturing the workpiece using a processing target object in which a groove is previously formed along a position where the processing target object should be cut.SOLUTION: A manufacturing method of a workpiece includes: a preparation step of preparing a processing target object 1 including at least a lead frame where a groove 5 is previously formed along a position where the processing target object should be cut; a surface layer removal step of partially removing a surface layer portion 3c, where the groove 5 is formed, in the processing target object 1 before cutting the processing target object 1; and a plating step of applying plating processing to the processing target object 1, from which the surface layer portion 3c is partially removed, before cutting the processing target object 1. In a state before implementing the surface layer removal step, the surface layer portion 3c includes a cut region 3m, which is removed by cutting the processing target object 1, and a non-cut region 3n positioned between the cut region 3m and an opening end 5 of the groove 5. In the surface layer removal step, at least a part of the non-cut region 3n is removed.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] This specification relates to a method for manufacturing a processed product, a method for manufacturing a semiconductor device, and a manufacturing apparatus for a processed product.

Background Art

[0002] As disclosed in Japanese Patent Application Laid-Open No. 2011-77278 (Patent Document 1), in a workpiece such as a lead frame, various processing treatments are performed on the workpiece alone or on an integrated body of the workpiece and other members such as resin, thereby obtaining a processed product (for example, a finished product). The workpiece (lead frame) disclosed in Patent Document 1 is subjected to plating treatment on the surface of the workpiece after a predetermined process, separated into individual pieces, and mounted on a substrate or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As disclosed in Patent Document 1, when preparing a workpiece, there may be a case where a workpiece having a groove portion (concave portion) formed in advance along the position to be finally cut is prepared. Due to the presence of the groove portion, for example, a plating film provided on the inner surface of the groove portion exhibits a concave space that is recessed inward after cutting the lead frame (after separation into individual pieces in Patent Document 1). A bonding material such as solder is induced into this concave space. For example, when mounting a semiconductor device on a substrate or the like, it becomes possible to satisfactorily bond solder to both the lower surface and the side surface of the lead, improving the connection reliability.

[0005] Here, when the object to be processed is in the state prepared in the preparation stage, the inner surface of the groove portion may have a surface shape curved in a concave shape, for example. In the state where the object to be processed is as prepared in the preparation stage, the inner surface of the groove portion may not have a surface shape suitable for processing in subsequent processes such as induction of solder or joining. In order to improve the connection reliability when using solder or the like, for example, it is preferable that the concave space is provided widely and the inner surface of the groove portion has a larger bonding area.

[0006] This specification is disclosed in view of the above circumstances, and when manufacturing a processed product using an object to be processed in which a groove portion is formed in advance along the position to be cut, it is possible to obtain higher connection reliability compared to the conventional method. An object of the present disclosure is to disclose a method for manufacturing a processed product, a method for manufacturing a semiconductor device, and a manufacturing apparatus for a processed product.

Means for Solving the Problems

[0007] A method for manufacturing a processed product according to the present disclosure includes a preparation step of preparing an object to be processed including at least a lead frame in which a groove portion is formed in advance along the position to be cut, and before cutting the object to be processed, a surface layer removing step of partially removing a surface layer portion forming the groove portion in the object to be processed, and a plating step of performing a plating process on the object to be processed in which the surface layer portion has been partially removed before cutting the object to be processed. In a state before the surface layer removing step is performed, the surface layer portion includes a cutting region that will be removed when the object to be processed is cut, and a non-cutting region located between the cutting region and the opening end of the groove portion. In the surface layer removing step, at least a part of the non-cutting region is removed.

[0008] The method for manufacturing a semiconductor device according to the present disclosure uses the above-described method for manufacturing a processed product. In a state where a semiconductor chip is bonded to the lead frame, a resin encapsulation step of encapsulating the lead frame and the semiconductor chip with a resin material, a resin removal step of removing the resin material in the groove portion, and a cutting step of cutting the lead frame along the groove portion are included. As the method for manufacturing the processed product, the surface removal step and the plating step are performed between the resin removal step and the cutting step, or the surface removal step and the plating step are performed at a stage prior to the resin encapsulation step, or the surface removal step is performed at a stage prior to the resin encapsulation step, and the plating step is performed between the resin removal step and the cutting step.

[0009] The manufacturing apparatus for a processed product according to the present disclosure is a manufacturing apparatus for a processed product that performs processing on a processing object including at least a lead frame in which a groove portion is formed in advance along a position to be cut. The manufacturing apparatus includes a surface removal unit that partially removes a surface portion forming the groove portion of the processing object in a state where the processing object is not cut, and a plating unit that performs plating on the processing object in a state where the surface portion is partially removed in a state where the processing object is not cut. In a state before the surface removal unit partially removes the surface portion, the surface portion includes a cutting region that will be removed when the processing object is cut, and a non-cutting region located between the cutting region and the opening end of the groove portion. The surface removal unit removes at least a part of the non-cutting region.

Effects of the Invention

[0010] According to the above disclosure, when manufacturing a processed product using a processing object in which a groove portion is formed in advance along a position to be cut, it is possible to obtain a method for manufacturing a processed product, a method for manufacturing a semiconductor device, and a manufacturing apparatus for a processed product that can achieve higher connection reliability compared to conventional methods.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] The embodiments will be described below with reference to the drawings. In the following description, the same parts and corresponding parts are given the same reference numerals, and duplicate descriptions may not be repeated. First, the configuration of the processed product manufacturing apparatus 20 and the lead frame 1 used in the processed product manufacturing method (or the semiconductor device manufacturing method) will be described, and then the processed product manufacturing method (or the semiconductor device manufacturing method) will be described.

[0013] [Processed Product Manufacturing Apparatus 20] FIG. 1 is a diagram showing a manufacturing apparatus 20 for a processed product. The manufacturing apparatus 20 for a processed product performs processing on a workpiece 22 held on a stage 21. A groove portion is formed in advance in the workpiece 22 along the position to be cut. Here, the groove portion is a groove portion with a bottom, and may be referred to as a bottomed groove. When the workpiece 22 is the lead frame 1 described later, a groove portion 5 (see FIG. 5 etc.) is formed in the lead frame 1, and the manufacturing apparatus 20 for a processed product can function as a manufacturing apparatus for semiconductor devices. In the following description, the description will be made based on an example in which the manufacturing apparatus 20 for a processed product is a manufacturing apparatus for semiconductor devices.

[0014] The manufacturing apparatus 20 for a processed product includes an emission unit 23, a scanning unit 24, a control unit 25, and a plating processing unit 26. The control unit 25 controls the emission unit 23 and the scanning unit 24 according to predetermined processing conditions. The emission unit 23 generates and emits laser light. The laser light emitted from the emission unit 23 is transmitted to the scanning unit 24, and the scanning unit 24 irradiates the workpiece 22 with the laser light L using, for example, a lens and a scanner mirror. The scanning unit 24 scans the laser light L along a predetermined scanning direction on the workpiece 22 by changing the relative position between the workpiece 22 and the beam spot of the laser light L. Thereby, a part of the workpiece 22 is removed.

[0015] Although details will be described later, the emission unit 23, the scanning unit 24, and the control unit 25 can function as a "surface removal unit". The surface removal unit partially removes the surface portion (surface portion 3c in the lead frame 1) that forms the groove portion (groove portion 5 (see FIG. 4) in the lead frame 1) of the workpiece 22 in a state where the workpiece 22 is not cut.

[0016] As will be described later with reference to FIG. 4, the surface portion 3c in the lead frame 1 is partially removed by laser irradiation from the surface removal unit. The plating processing unit 26 performs plating processing on the workpiece 22 (lead frame 1) in a state where the workpiece 22 (lead frame 1) is not cut and the surface portion 3c has been partially removed.

[0017] [Method for manufacturing semiconductor device] FIG. 2 is a diagram showing a method for manufacturing a processed product and a method for manufacturing a semiconductor device using the same. Using the processed product manufacturing apparatus 20 shown in FIG. 1, the method for manufacturing a semiconductor device can be implemented. The method for manufacturing a semiconductor device includes a preparation step ST10, a resin encapsulation step ST12, a resin removal step ST13, a surface layer removal step ST14, a plating step ST15, and a cutting step ST16. The preparation step ST10 includes a groove formation step ST11.

[0018] (Method for manufacturing processed product) The preparation step ST10, the surface layer removal step ST14, and the plating step ST15 can constitute a method for manufacturing a processed product. That is, the method for manufacturing a semiconductor device may include the method for manufacturing a processed product. Hereinafter, each step will be described in order.

[0019] [Lead frame 1 (preparation step ST10)] FIG. 3 is a plan view showing the configuration of the lead frame 1 prepared in the preparation step as viewed from the back surface 1b side. FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3. FIG. 5 is a perspective view showing the configuration of a part (lead portion 3, tie bar 4, and groove portion 5) of the lead frame 1 prepared in the preparation step as viewed from the back surface 1b side.

[0020] Although FIG. 3 does not represent the cross-sectional configuration of the lead frame 1, for the sake of illustration, hatching lines extending in an oblique direction are given to the portions constituting the lead frame 1. Here, two types of hatching lines are used, and the difference between them will be described later. In FIGS. 3 to 5, for the sake of explanation, the length direction S, the width direction W, and the height direction H are illustrated, and in the following description, these directions will be referred to as appropriate. These directions are also appropriately illustrated in the drawings after FIG. 6.

[0021] As shown in FIG. 3, the lead frame 1 has a substantially plate-like shape extending along both the length direction S and the width direction W. The lead frame 1 has a front surface 1a located on the side where the semiconductor chip 6 (FIG. 6) is mounted and a back surface 1b located on the side opposite to the front surface 1a, and is made of a metal such as copper. The lead frame 1 includes a plurality of die pads 2, a plurality of lead portions 3, and a plurality of tie bars 4.

[0022] (Die pad 2, lead portion 3, tie bar 4) The plurality of die pads 2 are arranged at intervals along both the length direction S and the width direction W. Lead frame 1 On the front surface 1a, the semiconductor chip 6 is mounted (see FIG. 6). Around each of the plurality of die pads 2 (on all four sides), a plurality of lead portions 3 are arranged side by side in a rectangular shape. A plurality of tie bars 4 are arranged in a grid pattern so as to surround each of the plurality of die pads 2. A plurality of lead portions 3 are provided on both sides of one tie bar 4, and the plurality of lead portions 3 are arranged at intervals along the extending direction of the tie bar 4. Each of the plurality of lead portions 3 has a thick portion 3a and a thin portion 3b (FIGS. 3 and 5). In the lead portion 3, the thick portion 3a is connected to the tie bar 4 via the thin portion 3b. In the height direction H, the die pad 2 and the thick portion 3a have a height dimension (i.e., thickness) larger than that of the thin portion 3b.

[0023] Hatching lines extending from the upper right side to the lower left side of the paper surface of FIG. 3 are provided on the die pad 2 and the thick portion 3a. Hatching lines extending from the upper left side to the lower right side of the paper surface of FIG. 3 are provided on the thin portion 3b of the lead portion 3 and the tie bar 4.

[0024] (Groove portion 5) Referring to FIG. 5, here, regarding the tie bar 4, the thick portion 3a and the thin portion 3b of the lead portion 3, when paying attention to the surfaces located on the "negative side of the height direction H" shown in FIG. 5, the height positions of these surfaces are the same. On the other hand, when paying attention to the surfaces located on the "positive side of the height direction H" shown in FIG. 5, the height position of the surface of the thick portion 3a of the lead portion 3 is higher than the height positions of the surface of the tie bar 4 and the surface of the thin portion 3b of the lead portion 3.

[0025] That is, the positive-side surface of the tab 4 and the positive-side surface of the thin-walled portion 3b of the lead portion 3 have a shape recessed with respect to the positive-side surface of the thick-walled portion 3a of the lead portion 3. With this structure, in the lead frame 1, a lattice-shaped groove portion 5 extending along the height direction H and the width direction W and extending along the height direction H and the length direction S is formed on the back surface 1b (FIG. 3) side of the tab 4.

[0026] The groove portion 5 does not penetrate the lead frame 1 in the height direction H. For example, it has a groove depth that is half of that of the lead frame 1 (thick-walled portion 3a) and can be formed by etching (wet etching) the lead frame 1. The groove width is, for example, 0.30 mm to 0.50 mm. The groove width and the groove depth may be set in consideration of ensuring a strength such that no problems such as deformation occur in subsequent processes, enabling a good appearance inspection in subsequent processes, and good mounting strength of the semiconductor device that is the finished product.

[0027] As shown in FIG. 4, the groove portion 5 is a space and is defined by a bottom portion 5a of the groove portion 5, a side portion 5b of the groove portion 5, and an opening end 5c of the groove portion 5. The opening end 5c of the groove portion 5 is the inner edge portion of the back surface 1b of the lead frame 1 where the groove portion 5 is formed and extends linearly (FIG. 5). The bottom portion 5a of the groove portion 5 generally has the shape of a flat surface. The side portion 5b of the groove portion 5 is curved so as to be positioned closer to the center in the width direction than the opening end 5c of the groove portion 5 as it approaches the bottom portion 5a of the groove portion 5.

[0028] As shown in FIGS. 4 to 5 (particularly FIG. 4), the lead frame 1 has a surface layer portion 3c that forms the groove portion 5. In FIG. 4, the surface layer portion 3c is represented using a dashed line. The surface layer portion 3c of the lead frame 1 is a portion defined within a range from the outer surface of the lead frame 1 to a predetermined depth, and is a portion that forms the groove portion 5. The surface shape of the surface layer portion 3c forms (defines) the groove portion 5 as a space. As shown in the cross-sectional shape of FIG. 4, the surface layer portion 3c has a predetermined thickness and extends here in a U-shaped or C-shaped form. Here, the "range up to a predetermined depth" and the "predetermined thickness" do not limit to the configuration where the surface layer portion 3c has a constant (uniform) thickness in the width direction W. As long as it forms the groove portion 5, the surface layer portion 3c can have an arbitrary thickness in the width direction W, and may have different thicknesses in the width direction W.

[0029] Details will be described later, but the lead frame 1 is individualized by performing a cutting process ST16 (see FIG. 14). The surface layer portion 3c includes a cutting region 3m that will be removed when the lead frame 1 is cut, and a non-cutting region 3n located between the cutting region 3m and the opening end 5c of the groove portion 5. In FIG. 4, the blade 12 used in the cutting process ST16 is virtually illustrated using a two-dot chain line.

[0030] The cutting region 3m is located inside the frame of the two-dot chain line indicating the blade 12, and the non-cutting region 3n is located outside the frame of the two-dot chain line indicating the blade 12. The surface layer portion 3c includes a boundary portion 3t between the cutting region 3m and the non-cutting region 3n. The surface 3q of the boundary portion 3t is located on the two-dot chain line indicating the blade 12. Note that the width and position of the frame of the two-dot chain line are both schematically described, and the actually removed range by cutting is wider than the width of the blade 12.

[0031] The surface shape 3p of the cutting region 3m corresponds to the bottom 5a of the groove portion 5. The surface shape 3r of the non-cutting region 3n corresponds to the side portion 5b of the groove portion 5. The upper end portion 3s of the surface shape 3r of the non-cutting region 3n corresponds to the opening end 5c of the groove portion 5. In the example shown in FIG. 4, all of the side portion 5b of the groove portion 5 is included in the surface shape 3r of the non-cutting region 3n. The bottom 5a (flat surface) of the groove portion 5 may be included in the lower end portion of the surface shape 3r of the non-cutting region 3n (in other words, a part of the bottom 5a of the groove portion 5 may be included in the non-cutting region 3n).

[0032] (Resin encapsulation process) FIG. 6 is a cross-sectional view showing a state in which a semiconductor chip 6 is bonded onto a lead frame 1 (die pad 2) prepared in the preparation process. As shown in FIG. 6, a plurality of electrodes provided on each semiconductor chip 6 are electrically connected to the lead portion 3 (thick portion 3a) via bonding wires 7.

[0033] FIG. 7 is a cross-sectional view showing a state in which the resin encapsulation process has been performed. In the resin encapsulation process, with the semiconductor chip 6 being bonded, the lead frame 1 and the semiconductor chip 6 are encapsulated with a resin material 9. Before the resin encapsulation process, a protective film 8 (for example, a polyimide resin tape) may be attached to the side of the groove portion 5 of the lead frame 1, and the resin encapsulation may be performed after the protective film 8 is attached.

[0034] The method for manufacturing a semiconductor device may further include a step of performing laser marking by irradiating a laser beam L1 onto the surface 9a (FIG. 7) on the side opposite to the groove portion 5 of the lead frame 1 somewhere between the resin encapsulation process and the cutting process described later. By scanning with a scanning optical system using a pulsed laser, arbitrary information such as a model number and a serial No can be printed.

[0035] As shown in FIG. 8, before performing the resin removal process described below, the protective film 8 is peeled off from the lead frame 1. By removing the protective film 8, the resin material 9 (9b) formed in the groove portion 5 of the lead frame 1 is exposed. Note that the protective film 8 may be peeled off from the lead frame 1 before the laser marking process described with reference to FIG. 7.

[0036] (Resin Removal Process) FIG. 9 is a cross-sectional view showing a state in which the resin removal process is being performed. In the resin removal process, the resin material 9 (9b) in the groove portion 5 is irradiated with the laser beam L2, and the laser beam L2 is scanned along the length direction S. As a result, the resin material in the groove portion 5 is removed. As the laser beam L2, for example, an infrared laser, a green laser, or an ultraviolet laser can be used as a pulsed laser.

[0037] Regarding the pulse width, a laser that generates a pulse width such as nanoseconds or picoseconds can be used. Further, by controlling the emitting unit 23 and the scanning unit 24 by the control unit 25 (FIG. 1), the processing conditions by the laser beam L2 can be changed. The wavelength, output, laser beam condensing diameter, irradiation time, etc. of the laser beam L2 are optimized so that the resin material 9 (9b) can be efficiently removed according to the material of the resin material 9 (9b) and the size of the resin material 9 (9b) (such as the groove width of the groove portion 5).

[0038] (Surface Layer Removal Process) FIG. 10 is a cross-sectional view showing a state in which the surface layer removal process is being performed. FIG. 11 is a plan view for explaining the range in which the surface layer removal process is performed. In the surface layer removal process, before cutting the lead frame 1 (in other words, before the cutting process is performed), the surface layer portion 3c forming the groove portion 5 of the lead frame 1 is partially removed. The surface layer removal process is performed, for example, using a laser. To efficiently process the material of the lead frame 1 (such as copper) and suppress the thermal influence, it is preferable to use an oscillator with a short pulse (less than picoseconds). The surface layer removal process may be performed by other grinding means or other polishing means.

[0039] Referring to FIG. 10, in the state before the surface removal process is performed, the surface portion 3c of the lead frame 1 includes a cutting region 3m that will be removed by cutting the lead frame 1, and a non-cutting region 3n located between the cutting region 3m and the opening end 5c of the groove portion 5. In the state before the surface removal process is performed, the surface shape 3r of the non-cutting region 3n is curved so as to be located closer to the center in the groove width direction than the opening end 5c of the groove portion 5 as it approaches the bottom 5a of the groove portion 5. Note that in FIG. 10, only the side wall portion of the blade 12 used in the cutting step ST16 is virtually illustrated using a two-dot chain line.

[0040] In the surface removal process, at least the non-cutting region 3n is irradiated with the laser beam L3, and the laser beam L3 is scanned along the length direction S (see FIG. 11). As a result, at least a part of the non-cutting region 3n is removed. For example, it is preferable to remove a depth of 30 μm to 40 μm from the surface portion 3c. As the laser beam L3, a short pulse laser such as a picosecond pulse laser may be used, for example.

[0041] FIG. 12 is a cross-sectional view showing an enlarged part of FIG. 10 and shows the state after the surface removal process is performed. In the example shown in FIGS. 10 and 12, the portion slightly below the central portion in the height direction in the non-cutting region 3n (closer to the bottom 5a of the groove portion 5) is removed. Further, both side portions in the width direction of the cutting region 3m are also slightly removed. That is, in the surface removal process here, in addition to at least a part of the non-cutting region 3n, the portion of the cutting region 3m closer to the non-cutting region 3n is also removed.

[0042] After the surface removal process is performed and before the lead frame 1 is cut, in the state of the surface portion 3c of the lead frame 1, the boundary portion 3t is included between the cut region 3m and the non-cut region 3n. When the position of the surface of the surface portion 3c in the depth direction of the groove portion 5 is defined as "height", after the surface removal process is performed and before the lead frame 1 is cut, the height H1 of the surface of the cut region 3m is equal to the height H2 of the surface 3q of the boundary portion 3t, or at least a part of the surface of the cut region 3m has a height H1 higher than the height H2 of the surface 3q of the boundary portion 3t (the height position of the surface 3q of the boundary portion 3t is at a height position lower than at least a part of the surface of the cut region 3m).

[0043] (Plating process) FIG. 13 is a cross-sectional view showing the state after the plating process is performed. After the surface removal process is carried out and before the lead frame 1 is cut, a plating treatment is performed on the lead frame 1 in which the surface portion 3c is partially removed. A plating layer 10 is formed on the surface of the die pad 2 of the lead frame 1, the surface of the tie bar 4 of the lead frame 1, the surface of the thin portion 3b of the lead portion 3, and the surface on which the surface removal process has been performed among the surface portions 3c. By forming the plating layer 10, the manufacturing method of the processed product is completed, and at this point, the lead frame 1 on which the plating layer 10 is formed constitutes the "processed product".

[0044] As the material of the plating layer 10, a material with good solder wettability can be selected according to the solder material used for mounting. For example, when using Sn (tin)-based solder, tin (Sn), tin-copper alloy (Sn-Cu), tin-silver alloy (Sn-Ag), tin-bismuth (Sn-Bi), etc. can be used.

[0045] In the plating process, it is advisable to perform a predetermined cleaning treatment on the lead frame 1 before the plating treatment. As surface treatment of the lead frame 1 in the pretreatment of the plating process, in addition to the cleaning treatment, treatment for removing an oxide film, surface activation, etc. may be performed. The resin material 9 in the groove portion 5 may be modified (for example, carbonized) by irradiation with laser light. Even when some resin material 9 remains, the modified resin material 9 can be removed from the groove portion 5 by surface treatment such as cleaning treatment before the plating treatment.

[0046] (Cutting Process) As shown in FIG. 14, the plated lead frame 1 is cut along the groove portion 5. In this cutting process, the blade 12 is used to cut the entire thickness portion of the lead frame 1 and the resin material 9. By carrying out the cutting process, semiconductor devices 11 as a plurality of unit resin molded products are obtained. As shown in FIG. 15, the semiconductor device 11 is a non-leaded type product of the QFN (Quad Flat Non-leaded Package) type in which leads for electrical connection do not protrude outward of the product in a plan view.

[0047] FIG. 16 is a cross-sectional view showing a state in which the semiconductor device 11 is implemented. As shown in FIG. 16, in the semiconductor device 11, a step is formed in a side portion (one portion) of each lead portion 3, and on the side surface 3d of the lead portion 3, no plating layer 10 is formed and the original metal is exposed. The semiconductor device 11 is mounted on a printed circuit board, for example, with the side of the resin material 9 facing up and the side of the lead portion 3 facing down. Lands 13 are formed on the printed circuit board at positions corresponding to the lead portions 3, and the lead portions 3 and the lands 13 are connected via solder 14.

[0048] At this time, the solder 14 accumulates in the inside (recess) of the portion where the surface removal process has been performed in the surface layer portion 3c (FIG. 12) of the lead frame 1, so that the wettability of the solder 14 is improved and a better solder joint structure can be obtained. By carrying out the surface removal process, the joint area (surface area) of the above-mentioned recess portion has become larger, and further, the volume of the recess portion capable of guiding the solder 14 has also become larger.

[0049] FIG. 17 is a cross-sectional view showing a state in which a semiconductor device obtained by the manufacturing method of the comparative example is mounted. In the case of the comparative example, since the surface layer removal step is not performed, both the bonding area (surface area) and the volume of the portion corresponding to the recess are small. On the other hand, according to the above-described embodiment (FIG. 16), when manufacturing a processed product using a workpiece in which a groove portion is formed in advance along the position to be cut, it is possible to obtain higher connection reliability than the conventional method. Further, by performing the surface layer removal step, the height HS of the above-described recess portion can be made higher, the inspection using an automatic inspection machine for inspecting the solder 14 becomes easier, and it is also possible to obtain a result with higher accuracy.

[0050] When the groove portion 5 of the lead frame 1 is formed by wet etching, the surface shape 3r of the non-cut region 3n is likely to be curved so as to be located closer to the center in the groove width direction than the opening end 5c of the groove portion 5 as it approaches the bottom portion 5a of the groove portion 5. When wet etching is performed, the above-described effect can be obtained by performing the surface layer removal step on the surface shape 3r of the non-cut region 3n as described above.

[0051] As shown in FIG. 18, in the above-described embodiment, when the position of the surface of the surface layer portion 3c in the depth direction of the groove portion 5 is defined as "height", after the surface layer removal step is performed and before the lead frame 1 is cut, the height H1 of the surface of the cut region 3m is equal to the height H2 of the surface 3q of the boundary portion 3t, or at least a part of the surface of the cut region 3m has a height H1 higher than the height H2 of the surface 3q of the boundary portion 3t. In the latter case, the height position of the surface 3q of the boundary portion 3t is at a height position lower than at least a part of the surface of the cut region 3m. According to this configuration, when cutting is performed using the blade 12, the blade 12 first contacts the portion having the height H1 in the cut region 3m. At this point, gaps 3w (FIG. 18) are formed below both sides in the width direction of the blade 12. Thereafter, the blade 12 comes into contact with the portion having the height H2 (the surface 3q of the boundary portion 3t) in the boundary portion 3t. Thus, since the thickness of the lead frame 1 becomes thinner at both ends of the blade 12, it is possible to reduce the occurrence of burrs at the boundary portion 3t.

[0052] [First Modified Example] FIG. 19 corresponds to FIG. 12 and is a cross-sectional view for explaining the surface layer removal step according to the first modified example of the embodiment. In the above example (FIG. 18, etc.), in addition to at least a part of the non-cut region 3n, the end portion of the cut region 3m (the portion corresponding to the gap 3w shown in FIG. 18) is also removed. Such a configuration is not essential. As shown in FIG. 19, when the cut region 3m is flat and the side portion 5b of the groove portion 5 is not included in the cut region 3m, the cut region 3m may not be removed in the surface layer removal step. The purpose of forming the above-described recesses that contribute to solder induction and bonding can also be achieved by performing the surface layer removal step only on the non-cut region 3n and not performing the surface layer removal step on the cut region 3m. By not performing the surface layer removal step on the cut region 3m, the manufacturing time can be shortened.

[0053] [Second Modified Example] FIG. 20 corresponds to FIG. 12 and is a cross-sectional view for explaining the surface removal process according to the second modification of the embodiment. After the surface removal process is performed and before the lead frame 1 is cut, the portion where the surface of the cut region 3m and the surface of the non-cut region 3n are connected to each other (that is, the surface of the boundary portion 3t) has a flat surface shape, and the flat surface may be substantially orthogonal to the depth direction of the groove portion 5 (the direction orthogonal to the back surface 1b). Also with this configuration, it is possible to reduce the generation of burrs at the boundary portion 3t.

[0054] FIG. 21 corresponds to FIG. 12 and is a cross-sectional view for explaining the surface removal process according to the third modification of the embodiment. As shown in FIG. 21, after the surface removal process is performed and before the lead frame 1 is cut, the surface shape 3r of the non-cut region 3n (that is, the side portion 5b of the groove portion 5) may extend so as to be substantially parallel to the depth direction of the groove portion 5 (the direction orthogonal to the back surface 1b). By performing the surface removal process to the extent shown in FIG. 21, it becomes possible to sufficiently form recesses that contribute to solder induction and bonding. Also, as the recesses become deeper, the solder wetting height on the mounting side surface is ensured during mounting of the semiconductor device, and inspection using an automatic inspection machine becomes easier.

[0055] Also, similar to the case described with reference to FIG. 20, as shown in FIG. 21, the portion where the surface of the cut region 3m and the surface of the non-cut region 3n are connected to each other (that is, the surface of the boundary portion 3t) has a flat surface shape, and the flat surface may be substantially orthogonal to the depth direction of the groove portion 5 (the direction orthogonal to the back surface 1b). In the configuration shown in FIG. 21, the surface shape 3r of the non-cut region 3n (that is, the side portion 5b of the groove portion 5) and the surface shape 3p of the cut region 3m (that is, the bottom portion 5a of the groove portion 5) are orthogonal to each other. Even with such a configuration, it is possible to reduce the generation of burrs at the boundary portion 3t.

[0056] [Fourth Modification Example] As described above, the preparation step ST10, the surface removal step ST14, and the plating step ST15 can constitute the manufacturing method of the processed product. In the case of the above-described embodiment (FIG. 2), the surface removal step ST14 and the plating step ST15 are performed between the resin removal step ST13 and the cutting step ST16.

[0057] FIG. 22 is a diagram showing a manufacturing method of a processed product and a manufacturing method of a semiconductor device using the same according to a fourth modification of the embodiment. As shown in FIG. 22, after performing each of these steps (preparation step ST10, surface removal step ST14, and plating step ST15) related to the manufacturing method of the processed product, a resin sealing step ST12, a resin removal step ST13, and a cutting step ST16 may be performed. In the example shown in FIG. 22, the surface removal step ST14 and the plating step ST15 are performed at a stage prior to the resin sealing step ST12. In the plating step in this case, for example, Palladium Pre Plated plating (for example, Ni / Pd / Au plating) or full-surface Pd plating can be used.

[0058] As an implementation entity, for example, a lead frame manufacturer can perform up to the plating step ST15, and a semiconductor device manufacturer can perform all of the steps after the resin sealing step ST12. Alternatively, a lead frame manufacturer can perform up to the surface removal step ST14, and a semiconductor device manufacturer can perform the steps after the plating step ST15.

[0059] [Fifth Modification Example] FIG. 23 is a diagram showing a manufacturing method of a processed product and a manufacturing method of a semiconductor device using the same according to a fifth modification of the embodiment. As shown in FIG. 23, these steps related to the manufacturing method of the processed product do not have to be performed continuously. After performing the preparation step ST10, the surface removal step ST14, the resin sealing step ST12, the resin removal step ST13, the plating step ST15, and the cutting step ST16 may be performed in order. In the example shown in FIG. 23, the surface removal step ST14 is performed at a stage prior to the resin sealing step ST12, and the plating step ST15 is performed between the resin removal step ST13 and the cutting step ST16.

[0060] As an implementation entity, for example, a lead frame manufacturer can perform up to the preparation process ST10, and a semiconductor device manufacturer can perform all processes after the surface removal process ST14. Alternatively, the lead frame manufacturer can perform up to the surface removal process ST14, and the semiconductor device manufacturer can perform the subsequent processes.

[0061] Although the embodiments have been described above, the above disclosure is illustrative in all respects and not restrictive. The technical scope of the present invention is indicated by the scope of the claims, and it is intended that all modifications within the meaning and scope equivalent to the scope of the claims be included.

Explanation of Reference Numerals

[0062] 1 Lead frame (object to be processed), 1a, 3q, 9a Surfaces, 1b Back surface, 2 Die pad, 3 Lead portion, 3a Thick portion, 3b Thin portion, 3c Surface layer portion, 3d Side surface, 3m Cutting region, 3n Non-cutting region, 3p, 3r Surface shapes, 3s Upper end portion, 3t Boundary portion, 3w Gap, 4 Tie bar, 5 Groove portion, 5a Bottom portion, 5b Side portion, 5c Open end, 6 Semiconductor chip, 7 Bonding wire, 8 Protection film, 9 Resin material, 10 Plating layer, 11 Semiconductor device, 12 Blade, 13 Land, 14 Solder, 20 Manufacturing apparatus for processed product, 21 Stage, 22 Object to be processed, 23 Emission portion, 24 Scanning portion, 25 Control portion, 26 Plating processing portion, H1, H2, HS Heights, L, L1, L2, L3 Laser beams, ST10 Preparation process, ST11 Groove formation process, ST12 Resin encapsulation process, ST13 Resin removal process, ST14 Surface removal process, ST15 Plating process, ST16 Cutting process.

Claims

1. A method for manufacturing a processed product, comprising: a preparation step of preparing a workpiece including at least a lead frame in which a groove portion is formed in advance along a position to be cut; a surface removal step of partially removing a surface layer portion of the workpiece that forms the groove portion before cutting the workpiece; a plating step of plating the workpiece with the surface layer portion partially removed before cutting the workpiece, wherein, in a state before the surface removal step is performed, the surface layer portion includes a cutting region that will be removed when the workpiece is cut and a non-cutting region located between the cutting region and an opening end of the groove portion; in the surface removal step, at least a part of the non-cutting region is removed; after the surface removal step is performed and before the workpiece is cut, the surface layer portion includes a boundary portion between the cutting region and the non-cutting region; when a position of a surface of the surface layer portion in a depth direction of the groove portion is defined as a height; after the surface removal step is performed and before the workpiece is cut, a height of a surface of at least a part of the non-cutting region is lower than a height of a surface of the boundary portion; after the surface removal step is performed and before the workpiece is cut, a height of a surface of at least a part of the cutting region is higher than a height of a surface of the boundary portion; A method for manufacturing a processed product.

2. In the surface removal step, in addition to the at least a part of the non-cutting region, a portion of the cutting region closer to the non-cutting region is also removed. The method for manufacturing a processed product according to Claim 1.

3. In a state before the surface removal step is performed, a surface shape of the non-cutting region is curved so as to be located closer to a center in a groove width direction than an opening end of the groove portion as it approaches a bottom portion of the groove portion. The method for manufacturing a processed product according to Claim 1 or 2.

4. The surface removal step is performed using a laser. The method for manufacturing a processed product according to any one of Claims 1 to 3.

5. The workpiece prepared in the preparation step has the groove portion formed by wet etching. The method for manufacturing a processed product according to any one of Claims 1 to 4.

6. A method for manufacturing a semiconductor device, which uses the method for manufacturing a processed product according to any one of claims 1 to 5, comprising: A resin encapsulation step of encapsulating the lead frame and the semiconductor chip with a resin material in a state where the semiconductor chip is bonded to the lead frame; A resin removal step of removing the resin material in the groove portion; A cutting step of cutting the lead frame along the groove portion, and As the method for manufacturing the processed product, The surface removal step and the plating step are performed between the resin removal step and the cutting step, The surface removal step and the plating step are performed at a stage prior to the resin encapsulation step, or The surface removal step is performed at a stage prior to the resin encapsulation step, and the plating step is performed between the resin removal step and the cutting step. A method for manufacturing a semiconductor device.

7. A manufacturing apparatus for a processed product that performs processing on a processing object including at least a lead frame in which a groove portion is formed in advance along a position to be cut, comprising: A surface removal unit that partially removes a surface layer portion forming the groove portion of the processing object in a state where the processing object is not cut; A plating unit that performs plating treatment on the processing object from which the surface layer portion has been partially removed in a state where the processing object is not cut, and In a state before the surface removal unit partially removes the surface layer portion, the surface layer portion includes a cutting region that will be removed when the processing object is cut, and a non-cutting region located between the cutting region and the open end of the groove portion. The surface removal unit removes at least a part of the non-cutting region. In a state before the surface removal unit partially removes the surface layer portion, the surface layer portion includes a boundary portion between the cutting region and the non-cutting region. When the position of the surface of the surface layer portion in the depth direction of the groove portion is defined as height, In a state before the surface removal unit partially removes the surface layer portion, the height of the surface of at least a part of the non-cutting region is lower than the height of the surface of the boundary portion. In a state before the surface removal unit partially removes the surface layer portion, the height of the surface of at least a part of the cutting region is higher than the height of the surface of the boundary portion. A manufacturing apparatus for a processed product.

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