KR20120116825A - Leadframe and method of manufacturig same - Google Patents

Abstract

PURPOSE: A lead frame and a manufacturing method thereof are provided to improve binding force between metal materials and a bonding force between molding materials by producing surface roughness on a surface of a lead frame raw material or a plating pattern. CONSTITUTION: A first lead(110a), a second lead(110b), and a die pad metal layer(115) are formed by plating both sides of a metal board. An insulation part groove is formed by etching an open surface of a lower side of a metal substrate. An insulation part(130) is formed by filling the insulation part groove with insulating materials. A die pad part and a lead part(102) which are disconnected each other are formed by etching an upper side of the metal board. A second lead is formed to be arranged in an outer side which is closer to the die pad part than the first lead.

Description

Lead frame and manufacturing method thereof {LEADFRAME AND METHOD OF MANUFACTURIG SAME}

The present invention relates to a lead frame and a method of manufacturing the same.

In the manufacture of semiconductor packages, lead frames play an important role in supplying input / output means for chip mounting and signal transmission, and various types of lead frames are being developed for highly integrated signal transmission.

In general, the shape of a lead frame manufactured is a die pad and a lead portion using an etching method or a stamping method. However, the conventional method of manufacturing the lead frame is not easy to form a multi-row lead required for high integration of the semiconductor.

The conventional lead frame by two-stage etching implements a circuit pattern through a two-stage etching process with a half etching, and the lower end of the half-etched circuit pattern has been proposed a lead frame in the form of fixing with a polyimide resin film.

However, in the structure of the lead frame by the conventional two-stage etching, the implementation pitch of the circuit pattern is 120 micrometers, there is a limit in the micro-implementation has a disadvantage that the number of lead pin (lead pin) that can be implemented is limited.

In addition, the polyimide resin film supporting the lower end of the circuit pattern has a weak supporting force, and there is no special protective film on the upper part of the circuit pattern, resulting in weak stability in the assembly process.

In addition, according to the conventional method, in order to mount the lead frame on the PCB substrate, there is a process troublesome process of performing tin plating for soldering.

The present invention has been made to solve the above problems, an object of the present invention is to provide a more integrated signal transmission system, a frame with improved molding power through the surface roughness and a lead frame for implementing the same simpler process It is to provide a manufacturing method.

As a means for solving the above problems, the present invention is to plate the both sides of the metal substrate to form a first lead, a second lead and a die pad metal layer, etching the exposed surface of the lower surface of the metal substrate to form an insulating groove And filling an insulating material into the insulating part groove to form an insulating part, and etching the upper surface of the metal substrate to form a die pad part and a lead part shorted to each other, wherein the second lead is formed on the die rather than the first lead. It is possible to provide a lead frame manufacturing method which is formed so as to be disposed outside on the side close to the pad portion.

Of course, in addition to the above-described manufacturing method process, before or after forming the first lead and the second lead, it may be implemented by a lead frame manufacturing method further comprising the step of surface roughening the surface of the metal substrate. .

In addition, in the above-described process, the insulating material may be filled in the insulating part groove to form the insulating part. The insulating material layer to be filled in the insulating part groove and the insulating layer may be implemented by laminating a metal layer on the insulating material layer.

In addition, forming the die pad portion and the lead portion in the above-described manufacturing process may include etching the insulating material layer and the metal layer to expose the first lead, the second lead, and the die pad metal layer on the lower surface of the metal substrate, The upper surface of the metal substrate may be etched to form die pad portions and lead portions shorted to each other.

In addition, etching the insulating material layer and the metal layer may allow etching to be performed in a structure in which the insulating material layer covers edge portions of the first, second lead and die pad metal layers. In this case, the first, second lead and the die pad metal layer may be formed of any one of the Ni, Au, Pd, Ag, or may be formed of a structure in which at least one or more of the metal layer formed of two or more alloys.

Unlike the above-described manufacturing process, the manufacturing method according to the present invention may be changed by the following process.

That is, unlike the above-described process, first, the lower surface of the metal substrate is etched to form an insulation groove, the insulation material is filled into the insulation groove to form an insulation portion, and both surfaces of the metal substrate are plated to form a first lead, Forming a second lead and a die pad metal layer and etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other, wherein the second lead is closer to the die pad portion than the first lead. It can be carried out by deforming to the process disposed on the side.

Of course, as described above, the surface roughness treatment process may be further included on the surface of the metal substrate before or after forming the insulation grooves by etching the lower surface of the metal substrate.

In addition, the surface roughness treatment may plate both surfaces of the metal substrate to form a first lead, a second lead, and a die pad metal layer, and surface roughness the surface of the metal substrate and the first lead, the second lead, and the die pad metal layer. You can also implement the process.

The insulating part may be filled by filling an insulating material in the insulating part groove to lay up and compress a metal layer on the insulating material layer and the insulating material layer to be filled in the insulating part groove, and press the insulating material layer and the metal layer. By selectively etching may be implemented by a process of exposing the lower die pad metal layer and the metal substrate of the formation region of the second lead.

In addition, in the present invention, the lead frame may be manufactured by a different process from the two process methods described above.

Specifically, both surfaces of the metal substrate are plated to form a first lead, a second lead, and a die pad metal layer, and the exposed surfaces of both surfaces of the metal substrate are first etched to form chip mounting grooves and an insulation part groove, and the insulation Forming an insulating part by filling an insulating material in the sub groove, and forming a die pad part and a lead part which are shorted to each other by second etching the upper surface of the metal substrate, wherein the second lead is formed on the die pad rather than the first lead. It is possible to implement a manufacturing method of the lead frame formed to be disposed on the outside close to the part.

In particular, in this case, the method may further include a step of surface roughening the surface of the metal substrate before or after forming the first lead, the second lead, and the die pad metal layer.

The etching of the insulating material layer and the metal layer may include filling an insulating material in the insulating part groove to form an insulating part by laying up an insulating material layer to be filled in the insulating part groove and a metal layer on the insulating material layer. And a method of manufacturing a lead frame in which primary etching is performed in a structure in which the insulating material layer covers edge portions of the first, second lead and die pad metal layers.

The lead frame according to the present invention manufactured by the above-described various processes, the lead portion having an insulating portion groove in the lower portion; A first lead plated at a position adjacent to the die pad part of an upper surface of the lead part; The lead may include a second lead plated on a lower surface of the lead portion, and the second lead may be implemented as a lead frame disposed closer to the die pad portion than the first lead.

In particular, in this case, the lead frame may further include a lower insulating part filled in the insulating part groove to support the lead part and the die pad part in a shorted state.

In addition, in the lead frame according to the present invention, surface roughness treatment may be implemented on at least one of the lead part, the first and second leads, and the die pad part.

In addition, the lower insulating portion of the lead frame according to the present invention may be formed to have a structure overlapping the edge portion of the die pad metal layer on the lower surface of the second lead or the die pad portion.

In addition, in the lead frame according to the present invention, the thickness of the thickest portion of the die pad portion may be formed to be equal to or less than the thickness of the lead portion, and the first lead, the second lead, and the die pad metal layer may include Ni, Au, and Pd. , Ag, or may be formed of a structure in which at least one or more layers of metal layers formed of two or more alloys are laminated.

In addition, the metal layer of the lead frame according to the present invention may be composed of any one of Cu, Al, Fe.

The multi-row leadframe manufactured by the present invention can implement three or more rows of I / O pads, which are difficult to realize in existing leadframes, through the implementation of a fine circuit, and can increase molding power by forming an insulator under the leadframe. Surface roughness may be implemented on the surface of the material or the plating pattern to improve the bonding strength between the metal materials and the bonding strength with the molding material.

In particular, through the surface treatment process to enhance the surface roughness applied to the process, it is possible to enhance the adhesion between the metal member and the insulator, and the adhesion between the I / O pad, SMT pad and the metal member, The surface of the product having an increased roughness of the lead wire also increases the adhesion to the molding epoxy in the assembly process, thereby preventing delamination.

In addition, as the distance between the chip and the wire bonding part approaches from the microcircuit pattern implementation of the lead frame according to the present invention, the use of the wire is reduced and the cost is reduced. In addition, since the wire bonding pad can be connected to the outer lead under the microcircuit by etching, a large number of signal transmission systems can be established, and the process number is simpler and manufacturing cost is lower than that of BGA with similar structure. , Circuit, that is, the lead portion and the die pad surface, because the metal member is used as it is, excellent signal transmission and thermal conductivity. Furthermore, the thickness of the entire semiconductor package can be adjusted by adjusting the depth of the chip mounting portion by etching.

As a result, a fine lead pitch can be realized in a thick material, and since the lead wire thickness is implemented at the end of the process, the stability of the product is high with respect to the process during product progress as a whole.

1A and 1B show a manufacturing process diagram for the present invention.
FIG. 2 is a conceptual diagram illustrating process features applied to the process of FIGS. 1A and 1B according to the present invention.
Figure 3 shows another embodiment of the manufacturing process of the method of manufacturing a lead frame according to the present invention.
4 is a conceptual diagram illustrating process characteristics applied to the process of FIG. 3.
5 and 6 show another manufacturing process according to the present invention.
7 to 10 are conceptual diagrams for explaining the characteristics of the process according to the present invention.
11 and 12 illustrate a concept of providing surface roughness to the first lead, the second lead, and the die pad metal layer in the manufacturing process according to the present invention.
It is a top view of the lead frame which concerns on one Embodiment of this invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description with reference to the accompanying drawings, the same reference numerals denote the same elements regardless of the reference numerals, and redundant description thereof will be omitted. Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

1. First embodiment

1A and 1B show a manufacturing process diagram for the present invention.

Both surfaces of the metal substrate are plated to form a first lead, a second lead, and a die pad metal layer, an exposed surface of the bottom surface of the metal substrate is etched to form an insulating groove, and an insulating material is filled into the insulating groove to form an insulating portion. And etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other. Particularly, in the present invention, the first lead is formed to be disposed outside the second lead. It features. Here, the outer side means that the second lead is formed at a position closer to the die pad portion than the first lead portion.

In the process according to the present invention, the method may further include a step of subjecting the surface of the metal substrate to the surface roughening before or after the formation of the first lead and the second lead.

Looking at the manufacturing process according to the present invention described above with reference to Figures 1a and 1b in detail,

In step (a), the metal substrate 100 is prepared as a member that is the main body of the circuit implementation. Here, the metal substrate 100 is preferably Cu, but a metal member such as Cu alloy, Fe, or an alloy thereof, which may be conductive, may be used. In addition, although the thickness of the metal substrate 100 is recommended to use less than 5mil to form a thin film substrate, it is also possible to use a member of less than 10mil. In the step (a), a process of performing roughness treatment on the surface of the metal substrate 100 may be further added. Such surface roughness treatment is implemented to improve the adhesion in the subsequent photosensitive material coating or plating process.

Thereafter, in step (b), the photosensitive film 120 is applied to both surfaces of the metal substrate 100, and then exposed through the photomask 130 on which the pattern is formed. Here, the pattern of the photo mask 130 is then formed to conform to the wire bonding pad (see FIG. 13 (a)) and the solder mounting pad (see FIG. 13 (c)).

On the other hand, as in step (c), the photosensitive film is removed in the unexposed portion, and the metal substrate of the removed portion is exposed (the process may be performed to remove the exposed portion). In particular, the exposed portions here correspond to the portions where the first and second leads will be formed later.

Thereafter, as in step (d), the metal substrate 100 exposed on both sides is plated to form the first lead 110a, the second lead 110b, and the die pad metal part 115. In this case, in the preferred embodiment according to the present invention, the first lead 110a is formed in a structure arranged outside the second lead 110b. That is, unlike the conventional structure, the second lead 110b is disposed close to the portion where the die pad metal layer 115 is formed, and the first lead 110a on the metal substrate 100 is formed on the die pad metal layer ( 115) is formed in a structure that is disposed at a relatively longer distance than the second lead in the formed portion.

Here, the plating process is preferably Ni plating, and in addition, at least one of Au, Pd, Ag on Ni may be plated. The implementation of such a plating layer generally proceeds with electroplating, but electroless plating, or electroplating and electroless plating may be used in combination.

After the implementation of the wire bonding pad part (the first lead 110a and the solder mounting pad part (the second lead 110b and the die pad metal part 115) by plating, the photosensitive film 120 is removed, and then, the step (e) is performed. As shown in the drawing, the lower surface of the metal substrate is etched to form the insulation grooves s.

Specifically, in step (e), after the step (d), the photosensitive material is coated again to proceed to the next process, and the upper surface proceeds without a pattern, and the upper surface of the mask pattern of exposure proceeds without a pattern, and the lower surface of FIG. 13 (c) The pattern of is applied to implement the exposure mask pattern, and after removing the photosensitive material of the lighted part (or the part not receiving the light) and proceeding the etching as shown in (e) It has a structure that is The photosensitive material used in this process is not a problem when applying the liquid-type photosensitive film (LPR), but when using the film-type photosensitive film (DFR), the vacuum lamination progresses when the photosensitive film adhesion decreases due to the difference between the steps of the member and the plating layer. Therefore, it is preferable to aim at the improvement of adhesive force.

In this case, after forming the insulating groove (s) in the step (e), the surface of the metal substrate 100 and the first and second leads (110a, 110b), the die pad metal layer 115, the insulating groove (s) The process of forming the surface roughness on the entire surface of the) may be added. Further additionally after the surface roughness treatment is performed in step (a). Of course, if the surface roughness treatment step is not added in step (a), the surface roughness treatment may be performed in this step.

Thereafter, in step (h) to (g), a layer-up of an insulating material layer 130 such as epoxy processed on the bottom surface of the metal substrate 100 and a metal layer 140 serving as a support role are performed. Apply heat and pressure to make close contact. The insulating material layer 130 may be processed by a drill, laser, or punching method, and the processed cross section is formed with a hole, such as the insulating material layer shown in (f), and the hole is shown in the drawing. In (c), the part corresponds to the SMT pad part. The insulating material layer (epoxy) processing has an advantage of facilitating the etching process of the insulating material layer (epoxy) to be carried out later.

As the insulating material layer used in the present invention, an epoxy material in which glass fibers are embedded may be used to increase the rigidity of a product made of PP (Prepreg). In this case, the drill method may be used to easily remove the glass fibers. Hole processing of the SMT Pad part was performed.

The thickness of the epoxy material used is determined by the etching depth of the lower surface etched in Fig. 13 (c). In this case, it is most preferable that the difference be less than ± 5 μm from the etching depth, and it is preferable not to use a material that differs by more than 10 μm if possible.

The used metal layer 140 serves as a pattern masking so that the plated SMT pad part can remove only the portion covered by the epoxy material, and at the same time, supports the member weakened by etching, thereby facilitating the subsequent process. The metal layer 140 may be used as an etchable metal material such as Cu, Al, Fe, etc., and the thickness used is not limited. In this embodiment, a member having a thickness of 20, 35, 70, 100, or 125 um is used, and a metal member of 100 um or more may be used for a desired pattern etching. Used metal members can be removed as needed after all processes have been completed.

Thereafter, in steps (h) to (i), only the epoxy and the metal layers are selectively etched and removed to completely expose the plated surfaces of the second lead and die pad metal layers formed on the bottom surface of the metal substrate 100. In particular, in this case, as shown in FIG. 10, the edge portions of the second lead and the die pad metal layers are left in a structure in which one portion overlaps so as to be covered by the epoxy (insulating material layer). It is more desirable to maintain a firm bonding force of the pad metal layer.

Subsequently, in the step (j), the photosensitive film is coated, and the upper surface of the metal substrate is subjected to an exposure process without a pattern as shown in FIG. 13 (b), and the lower surface is patterned to form a photosensitive material, followed by etching of the upper surface of the metal substrate. Proceeding to the above, the lower insulating layer is made possible to divide the members connected together due to the exposure of the epoxy, it is possible to divide into the die pad portion 101 and the two lead portion 102. Here, if the mask pattern used in the process (c) of FIG. 1 is applied to FIG. 13 (b) and the bottom surface is etched by applying the pattern of FIG. 13 (c), it is easy to implement a fine circuit pattern in a subsequent process.

FIG. 2 is a process feature applied to the process of FIGS. 1A and 1B according to the present invention, and in steps (a) or (e) of FIG. 1A, that is, before or after the formation of the first and second leads. The result of performing the process of forming the surface roughness on the metal substrate 100 or the first and second leads is shown.

That is, the rough Cu is plated on the entire surface of the member by increasing the surface roughness. This is because after the lower surface etching is performed in step (a) of FIG. 1a or step (e), before or after plating the wire bonding pad part and the solder mounting pad part (SMT pad part). You can proceed later.

This rough surface roughness is 100-400nm and its thickness can be 0.3 ~ 1.5um. Roughly formed surface roughness enhances the adhesion to the epoxy bonded to the lower surface portion, and the roughness of the upper lead wire is effective to prevent delamination by increasing the adhesion to the molding epoxy. In addition, rough Cu plating before the wire bonding pad and the solder mounting pad portion (SMT pad portion) plating may increase the adhesion between the member and the plating pad and may also increase the surface roughness of the plating portion.

2. Second Embodiment

Figure 3 shows another embodiment of the manufacturing process of the method of manufacturing a lead frame according to the present invention.

The basic process is (a) etching the bottom surface of the metal substrate 100 (b) to form an insulating groove (s) first, and in step (c) ~ (d) the insulating material layer 130 and the metal layer 140 After the process of laminating and compressing is performed, only the epoxy and the metal layers are selectively etched and removed to completely expose the lower surface of the metal substrate 100 in steps (e) to (f).

In this case, in the process of forming the insulating portion groove (s), after implementing the pattern to plate the die pad metal layer in the center, it is preferable to implement the pattern so that the second lead can be formed on both sides. Of course, in this case, a step of roughening the surface in step (a) or step (b) may be added.

Subsequently, in step (g), after forming the first lead 110a, the second lead 110b, and the die pad metal part 115 through plating as in steps (b) to (d) of FIG. In step (h), the upper surface of the metal substrate is etched 111 to expose the insulating material layer, thereby forming the die pad portion 101 and the lead portion 102 shorted to each other. In particular, in this case, the first lead 110a is formed to have a structure disposed outside the second lead 110b. That is, unlike the conventional structure, the second lead 110b is disposed close to the portion where the die pad metal layer 115 is formed, and the first lead 110a on the metal substrate 100 is the die pad metal layer. The portion 115 is formed to have a structure that is disposed at a relatively longer distance than the second lead.

The process of this embodiment is different from the first embodiment in that the lower insulating grooves are formed before the first lead 110a, the second lead 110b, and the upper and lower die pad metal portions 115 are formed. . In addition, in the second embodiment, a surface roughening process may be performed in steps (a) and (b) of FIG. 3, and FIG. 4 illustrates a result of performing such surface roughness treatment.

This rough surface roughness is 100-400nm and its thickness can be 0.3 ~ 1.5um. Roughly formed surface roughness enhances the adhesion to the epoxy bonded to the lower surface portion, and the roughness of the upper lead wire is effective to prevent delamination by increasing the adhesion to the molding epoxy. In addition, the rough Cu plating before the wire bonding pad and the solder mounting pad portion (SMT pad portion) may increase the adhesion between the member and the plating pad and may also increase the surface roughness of the plating portion. same.

3. Third Embodiment

5 shows another manufacturing process according to the present invention.

In the present exemplary embodiment, in the steps (a) to (d), the photosensitive material 120 is coated on the upper and lower surfaces of the metal substrate 100, and the photosensitive material 120 is disposed on the upper and lower surfaces of the metal substrate through an exposure mask m. A pattern is formed, and the first lead 110a, the second lead 110b, and the die pad metal part 115 are formed through plating, and the photosensitive material is peeled off. In particular, even in this case, unlike the conventional structure, the second lead 110b is disposed close to the portion where the die pad metal layer 115 is formed, and the first lead 110a on the metal substrate 100 is disposed. The die pad metal layer 115 may be disposed at a relatively longer distance than the second lead.

In this case, after the step (a) or (d), a step of performing roughness treatment on the surface of the metal substrate 100 may be further added. Such surface roughness treatment is implemented to improve the adhesion in the subsequent photosensitive material coating or plating process.

Subsequently, in step (e), the photosensitive material 120 is secondly applied, exposed and developed through a mask (m) to implement a pattern as in (f), and then, as in step (g), a metal substrate Both surfaces of the 100 are first etched.

In this case, it is important that the primary etching is such that the metal substrate 100 does not penetrate. This is because when the metal substrate 100 is drilled, the formation of a fine circuit that proceeds later may not proceed smoothly. As such, the thickness of the metal substrate 100 remaining after the upper and lower etching of the metal substrate 100 is preferably 10-30 μm. It may be less than 10um, but the puncture of the member may appear, so care should be taken during the etching process. In particular, in this step, the chip mounting groove is formed by etching a portion of the upper surface of the metal substrate 100 on which the chip is to be mounted. In particular, after the completion of the step (g), the surface of the metal substrate 100 where the etching is performed, the surface of the insulator groove, the surface of the upper first lead 110a, the die pad metal layer 115 and the second lead 110b are performed. Surface roughness treatment may be performed on the surface of the.

Subsequently, in steps (h) to (i) of FIG. 6, the insulating material layer 130 and the metal layer 140 are formed on the lower surface of the metal substrate 110, and the metal substrate (j) to (k) is formed. Only the epoxy and metal layers are selectively etched away so as to be fully exposed to the plated surfaces of the second lead and die pad metal layers formed on the bottom surface of 100). Then, as in (l), the upper surface of the metal substrate is etched to separate the two lead portions 102 and the die pad portion 101.

In the third embodiment, a surface roughness treatment process may be added in the processes (a), (d), and (g). In addition, in the subsequent process, an additional secondary etching is performed on the portion etched on the metal substrate 100 in the process step (l) in the first etched portion on the metal substrate.

Not only can the thickness of the lead wire connecting the wire bonding portion and the solder mounting portion be thinned through the simultaneous etching of the portion of the metal substrate 100 which is pre-etched on the upper portion of the metal substrate 100, but also the etching of the member surface which is not etched. Enables fine circuit line width implementation. In particular, it is possible to implement a thin thickness of 5 ~ 10um as needed.

This is made possible by applying the pattern of FIG. 13 (a) to the upper surface mask pattern of the exposure that proceeds to make the structure as shown in FIG. 1 (c) described above. That is, the etching of Fig. 13 (a) or Fig. 13 (b) on the upper surface of the metal substrate can reduce the height of not only the lead wire but also the portion where the die chip is placed as shown in Fig. 7.

As a result, the thickness and line width of the lead wire, and the height of the die pad portion can be adjusted simply by adjusting the etching depth and the ratio of the preprocess. Such a process has an advantage that the lower etching is not required to be excessively performed in the previous process in order to implement a fine circuit pattern and lower the thickness of the lead wire.

The epoxy filled in the insulator groove in the lower portion of the metal substrate serves to support the divided lead wire later, and furthermore, the adhesion force with the molding material can be effectively maintained during molding after die chip mounting.

FIG. 8 is an implementation of the first and second etching processes of FIG. 7, to show that the thickness of the lead wire may be controlled by adjusting the etching depth. For example, suppose that the upper etch depth t1 is 30 um and the lower etched depth t2 is 65 um when using a 5 mil member. The member a1, which is protected by the photosensitive film and is not etched, is left at a thickness t3 of 60 um.

After the secondary etching proceeds in the process to a depth of 30 um, t1 depth is t4 and lead wire separation proceeds. At the same time, the thickness of the lead wire enables a thin lead with a thickness of 30 um from t3 to t5.

At the same time, as shown in Fig. 13B, the etching depth to the portion where the die chip is raised can be adjusted. That is, the die chip is placed on the etched portion, thereby making it possible to slim down the package, which can be thickened due to the use of a thick member.

In FIG. 10 (a), d1 is the bump diameter, d2 is the diameter of the exposed metal layer pattern, d3 is the diameter of the plating first and second lead or die pad metal layers, and d3 is larger than d1 and d2 as shown in the drawing. And d2 may be large or the same. Taking d1 smaller than d3 strengthens the bonding of the insulating layer and the member in such a manner that the plating end portion enters the insulating layer as shown in FIG. 10 (b).

Taking d2 smaller than d3 is to prevent the inside epoxy from being damaged as the etching liquid penetrates into the metal layer during the epoxy etching. In addition, in order for a smooth epoxy etching to proceed, it is preferable that the epoxy thickness t6, which is the remaining insulating material layer, does not exceed 20 μm, and it is most preferable to leave it below 5 μm (Fig. 10 (b)).

11 and 12 illustrate a concept of providing surface roughness to a plating pattern (a first lead, a second lead, and a die pad metal layer) used as a wire bonding pad and a solder mounting pad in a manufacturing process according to the present invention.

Basically, the plating pattern according to the present invention may be formed of any one of Ni, Au, Pd, Ag, or may be formed in a structure in which at least one or more layers of metal layers formed of two or more alloys are stacked.

In this case, various plating lamination patterns such as (a) to (f) may be implemented, and FIG. 12 illustrates a rough Ni plating process to give a separate surface roughness to the plating layer. Rough Ni plating exhibited a surface roughness of between 300 and 800 nm, and its thickness can be adjusted as needed from 0.3 to 1.2 um.

In the lead frames manufactured in the first to third embodiments described above, referring to the structures of FIGS. 1B, 3H, and 6L, the metal substrate 100 may be etched. Implemented through patterning, but consequently includes a lead portion 102 having an insulation groove in the lower portion.

In particular, in this case, the second lead formed on the lower surface of the lead part may have a structure in which it is disposed at a position adjacent to the die pad part 101 relative to the first lead 110a and d. In addition, the structure further includes a lower insulator 130, which is filled in the insulator groove and supports the lead unit and the die pad unit in a shorted state, and particularly, the lead unit, Surface roughness treatment is implemented on at least one of the first and second leads and the die pad unit.

Although described in the embodiment of each manufacturing process, in the structure having an epoxy filled in the lower insulating portion groove of the lead frame according to the present invention, the lower insulating portion, the die pad metal layer on the lower surface of the second lead or the die pad portion The structure described above in FIG. 10 overlapping an edge portion of the die pad may be formed in such a manner that the thickness of the thickest portion of the die pad portion is laminated to at least one or more layers of metal formed below the thickness of the lead portion. .

In the foregoing detailed description of the present invention, specific examples have been described. However, various modifications are possible within the scope of the present invention. The technical spirit of the present invention should not be limited to the above-described embodiments of the present invention, but should be determined by the claims and equivalents thereof.

110: metal substrate
101: die pad portion
102: lead portion
110a: first lead
110b: second lead
115: die pad metal layer
130: insulating material layer / insulation
140: metal layer

Claims (20)

Plating both sides of the metal substrate to form a first lead, a second lead, and a die pad metal layer;
Etching the exposed surface of the lower surface of the metal substrate to form an insulating portion groove,
Filling an insulating material into the insulating part groove to form an insulating part,
Etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other,
The lead frame manufacturing method of the second lead is formed to be disposed on the outside closer to the die pad portion than the first lead.
The method according to claim 1,
Before or after forming the first lead and the second lead,
Lead frame manufacturing method further comprising the step of performing a surface roughness treatment on the surface of the metal substrate.
The method according to claim 2,
Filling the insulating material in the insulating portion groove to form an insulating portion,
A method of manufacturing a lead frame in which an insulating material layer to be filled in the insulating part groove and a metal layer are laid up and pressed on the insulating material layer.
The method according to claim 3,
Forming the die pad portion and the lead portion,
Etching the insulating material layer and the metal layer to expose the first lead, the second lead, and the die pad metal layer on the lower surface of the metal substrate;
And etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other.
The method of claim 4,
Etching the insulating material layer and the metal layer,
And the etching is performed in such a manner that the insulating material layer covers edge portions of the first, second lead and die pad metal layers.
The method of claim 4,
The first, second lead and the die pad metal layer,
The Ni, Au, Pd, Ag made of any one, or a method of manufacturing a lead frame formed of a structure laminated at least one or more of the metal layer formed of two or more alloys.
The lower surface of the metal substrate is etched to form an insulating groove.
Filling an insulating material into the insulating part groove to form an insulating part,
Plating both surfaces of the metal substrate to form a first lead, a second lead, and a die pad metal layer;
Etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other,
And the second lead is disposed closer to the die pad portion than the first lead.
The method of claim 7,
Before or after forming the insulation grooves by etching the lower surface of the metal substrate,
Lead surface manufacturing method further comprises a surface roughening process on the surface of the metal substrate.
The method of claim 7,
Plating both surfaces of the metal substrate to form a first lead, a second lead, and a die pad metal layer;
And a surface roughening process on the surface of the metal substrate and the first lead, the second lead, and the die pad metal layer.
The method according to claim 8 or 9,
Filling the insulating material into the insulating portion groove to form the insulating portion,
Lay-up and compress the insulating material layer to be filled in the insulating portion groove and the metal layer on the insulating material layer,
Selectively etching the insulating material layer and the metal layer to expose a metal substrate at a portion where the lower die pad metal layer and the second lead are formed.
Plating both sides of the metal substrate to form a first lead, a second lead, and a die pad metal layer;
First etching the exposed surfaces of both sides of the metal substrate to form chip mounting grooves and insulating part grooves;
Filling an insulating material into the insulating part groove to form an insulating part,
Secondarily etching the upper surface of the metal substrate to form a die pad portion and a lead portion shorted to each other,
And the second lead is formed to be disposed outward from a side closer to the die pad portion than the first lead.
The method of claim 11,
And a surface roughening process on the surface of the metal substrate before or after the first lead, the second lead, and the die pad metal layer are formed.
The method of claim 12,
Etching the insulating material layer and the metal layer,
Filling an insulating material into the insulating part groove to form an insulating part,
Lay-up and compress the insulating material layer to be filled in the insulating portion groove and the metal layer on the insulating material layer,
And a first etching is performed in such a manner that the insulating material layer covers edge portions of the first, second lead, and die pad metal layers.
A lead portion having an insulation portion groove in a lower portion thereof;
A first lead plated at a position adjacent to the die pad part of an upper surface of the lead part;
It includes a second lead plated on the lower surface of the lead portion,
And the second lead is disposed closer to the die pad portion than the first lead.
The method according to claim 14,
And a lower insulating part filled in the insulating part groove to support the lead part and the die pad part in a shorted state.
15. The method according to claim 14 or 15,
A lead frame in which a surface roughness treatment is implemented on at least one of the lead part, the first and second leads, and the die pad part.
18. The method of claim 16,
The lower insulation portion,
And a lead frame formed to overlap an edge portion of the die pad metal layer below the second lead or the die pad part.
18. The method of claim 16,
And a thickness of the thickest portion of the die pad portion is less than or equal to the thickness of the lead portion.
18. The method of claim 16,
The first lead, the second lead and the die pad metal layer,
Lead frame formed of any one of the Ni, Au, Pd, Ag, or a structure in which at least one or more of the metal layer formed of two or more alloys are laminated.
18. The method of claim 16,
The metal layer may include,
Lead frame is any one of Cu, Al and Fe.

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