JP6789965B2 - Lead frame material and its manufacturing method - Google Patents

Description

The present invention is a lead frame material used in a resin-sealed semiconductor device in which a semiconductor element and a plated lead frame are electrically connected to each other and sealed with a mold resin, and a method for manufacturing the same. Regarding.

In this type of resin-sealed semiconductor device, a semiconductor element electrically connected to each other by a wire or the like and a lead frame are sealed with a mold resin. In such a resin-sealed semiconductor device, the lead frame is mainly plated with an exterior such as Sn-Pb or Sn-Bi.

Here, in recent years, in order to simplify the assembly process and reduce costs, plating (for example, Ni /) on the surface of the lead frame in advance with specifications that enhance the wettability with solder when mounting on a printed circuit board by soldering or the like. Lead frames with Pd / Au) (Pre Plated Frame, hereinafter abbreviated as PPF) have begun to be adopted (see, for example, Patent Document 1).

On the other hand, in order to improve the adhesion between the lead frame and the mold resin in the resin-sealed semiconductor device, a technique for roughening the plated surface of the lead frame has been proposed (for example, Patent Document 2 and Patent Document). 3).

These techniques for roughening the plated surface are: (1) the effect of increasing the adhesive area of the lead frame with the mold resin by roughening the plated surface of the lead frame, and (2) the roughened plating film. It is expected that the mold resin will easily bite into the unevenness (that is, the anchor effect).

As a result, the adhesion of the lead frame to the mold resin is improved, peeling between the lead frame and the mold resin can be prevented, and the reliability of the resin-sealed semiconductor device is improved.

Japanese Patent Application Laid-Open No. 4-115558 Japanese Patent Application Laid-Open No. 6-29439 Japanese Patent Application Laid-Open No. 10-27873

The roughened plating with these shapes was able to improve the resin adhesion as compared with the conventional case. However, it has been found that there are some cases where a gap is formed between the resin and the lead frame after 168 hours in an environment of high reliability required in recent years, for example, a temperature of 85 ° C. and a humidity of 85%. It was. As for this, packages such as QFN (Quad Flat Non-Leaded Package) type and SOP (Small Outline Package) type, which have not been widely used in the past, are often used, and the required level for adhesion becomes higher. It is thought that it was because it came. In this way, it turned out that there is still room for improvement.

An object of the present invention is to provide a lead frame material suitable for producing a lead frame capable of improving resin adhesion in a high temperature and high humidity environment required in recent years, and a method for producing the same.

As a result of diligent research and development on the above-mentioned conventional problems, the present inventors focused on the shape of the roughened layer formed on the conductive substrate, and maximized the anchor effect between the lead frame material and the resin. We diligently examined the shapes that can appear only. As a result, not only the vertical roughened layer (roughened layer formed at least one layer in the vertical direction of the substrate) but also at least one layered roughened layer (roughened shape) on the upper layer thereof. Among the irregularities of the vertical roughening layer and the additional roughening layer, the distance between the vertices of the adjacent convex portions (ridges of the unevenness) of the vertical roughening layer and the adjacent convex portions of the additional roughening layer. It has been found that the resin adhesion can be remarkably improved as compared with the conventional case and the resin adhesion in the high temperature and high humidity test can be ensured by making the distance between the vertices of the (uneven mountain) different. The present invention has been completed based on this finding.

That is, the present invention provides the following means:
(1) In a lead frame material having a roughened layer on a conductive substrate, the roughened layer is composed of a plurality of roughened layers, and the roughened layer is formed from at least one layer in the vertical direction of the conductive substrate. In addition to having a vertical roughening layer, at least one additional roughening layer is provided on the upper layer of the vertical roughening layer, and among the irregularities of the vertical roughening layer and the additional roughening layer, the additional roughening is performed. A lead frame material, characterized in that the average distance between the vertices of adjacent convex portions of the chemical layer is 1/20 or more and 3/4 or less of the average distance between the vertices of adjacent convex portions of the vertical roughening layer .
(2) Line segment length of the outermost layer cross section (line segment length of the outermost layer cross section; the line segment length of the cross section of the outermost layer of the lead frame material including the additional roughening layer) (A) and conductivity. The lead frame material according to (1), wherein the value of the ratio (A / B) of the line segment length of the base cross section (conductive base cross section line segment length) (B) is 1.2 or more and 4 or less.
(3) The lead frame material according to (1) or (2), wherein the conductive substrate is copper or a copper alloy, iron or an iron alloy, aluminum or an aluminum alloy.
(4) The plurality of roughened layers are composed of two layers, a first vertical roughened layer roughly roughened in the vertical direction of the conductive substrate, and a second additional roughened layer above the vertical roughened layer. The lead frame material according to any one of (1) to (3), wherein the components of the vertical roughening layer and the additional roughening layer are different.
( 5 ) The lead frame material according to any one of (1) to ( 4 ), wherein the component of the vertically roughened layer is made of copper or a copper alloy.
( 6 ) The lead according to any one of (1) to ( 5 ), wherein the component of the additional roughened layer is composed of any one of nickel, nickel alloy, cobalt, and cobalt alloy. Frame material.
( 7 ) The conductive substrate has a vertical roughened layer roughened in the vertical direction, has an additional roughened layer as an upper layer of the vertical roughened layer, and has palladium as an upper layer of the additional roughened layer. , Palladium alloy, rhodium, rhodium alloy, ruthenium, ruthenium alloy, platinum, platinum alloy, iridium, iridium alloy, gold, gold alloy, silver, silver alloy, all or part of the surface layer of the lead frame material The lead frame material according to any one of (1) to ( 6 ), which has a single layer or a plurality of layers.
( 8 ) The lead frame according to any one of (1) to ( 7 ), wherein either or both of the vertical roughening layer and the additional roughening layer are formed by electroplating. Material manufacturing method.
( 9 ) A semiconductor package using the lead frame material according to any one of (1) to ( 7 ) above.

In a lead frame material having a roughened layer formed on a conductive substrate, the present inventors have formed the roughened layer composed of a plurality of roughened layers, and the roughened layer is conductive. It has at least one vertical roughening layer formed in the vertical direction of the substrate, and also has at least one additional roughening layer in which the upper layer of the vertical roughening layer is roughened. Among the irregularities of the chemical layer and the additional roughening layer, the distance between the apex of the adjacent convex portion of the vertical roughening layer and the distance between the apex of the adjacent convex portion of the additional roughening layer should be different. Therefore, the resin penetrates not only in the vertical direction but also in the horizontal direction of the substrate, and not only the surface area is increased by the conventional roughening treatment, but also the bonding strength with the mechanical resin is caused by the wedge action of the additional roughening layer. Was found to increase significantly. As a result, the high-temperature and high-humidity adhesion of the resin, which could not be tolerated in the past, for example, even in a high-temperature and high-humidity environment of 168 hours at 85 ° C. and 85%, a large gap is generated between the lead frame material and the resin. It is suppressed to and excellent resin adhesion can be obtained.

FIG. 1 is a schematic cross-sectional schematic diagram according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional schematic view of another embodiment of the present invention. FIG. 3 is a schematic cross-sectional schematic view of still another embodiment of the present invention. FIG. 4 is an enlarged view of a schematic cross-sectional view according to an embodiment of the present invention. FIG. 5 is an enlarged view of a schematic cross-sectional schematic diagram of the above embodiment shown in FIG. 4 of the present invention. FIG. 6 is a schematic cross-sectional schematic diagram of a conventional form. In FIG. 6, 11 is a conductive substrate, 12 is a copper base plating layer, 13 is a nickel roughened plating layer, and 14 is a surface layer.

(Vertical roughening layer)
According to the present invention, first, a roughening layer in the direction perpendicular to a conductive substrate (hereinafter, simply referred to as a substrate), that is, a vertical roughening layer is provided. The roughened layer of the lead frame material is composed of a plurality of vertical roughened layers, and preferably has one vertical roughened layer. This vertically roughened layer indicates a roughened layer formed in the direction perpendicular to the main surface of the substrate, and means a layer formed substantially in the direction perpendicular to the main surface of the substrate. When observed from a vertical cross section in the vertical direction with respect to the substrate, it is preferable that the growth direction of the convex portion of the roughened layer (at the apex of the mountain) is formed within 20 ° from the perpendicular line of the main surface of the substrate. .. This vertical roughened layer is a roughened layer that serves as a basis for imparting resin adhesion, and is preferably made of, for example, copper, a copper alloy, nickel, a nickel alloy, cobalt, or a cobalt alloy. In particular, a vertically roughened layer made of copper or a copper alloy is more preferable from the viewpoint of improving the adhesion between the substrate and the upper film (such as the additional roughened layer described below). Examples of copper alloys, nickel alloys, and cobalt alloys include copper-tin alloys as copper alloys, nickel-zinc alloys as nickel alloys, and cobalt-tin alloys as cobalt alloys.

(Film thickness of vertical roughened layer)
The thickness of the vertical roughening layer is not particularly limited, but the larger the film thickness, the larger the unevenness due to roughening tends to be. Therefore, the coating thickness of the vertical roughened layer is preferably 0.2 μm or more, more preferably 0.5 μm or more, and further preferably 0.8 μm or more in order to increase the roughened shape. On the other hand, if the coating thickness exceeds 3 μm, there is a concern that the roughened layer may fall off during transportation, so-called “powder drop”. Therefore, the coating thickness of the vertical roughening layer is preferably 3 μm or less, more preferably 2 μm or less, and further preferably 1.5 μm or less. Further, it is preferable that the number of vertical roughened layers is 2 or less in consideration of the complexity of the manufacturing process. These coating thicknesses are not determined locally, and at least any three points are measured with a collimator diameter of 0.2 mm or more by a fluorescent X-ray method (for example, a film thickness measuring device such as SFT9400 (trade name) manufactured by SII). It shall show the average film thickness.

(Additional roughening layer)
Further, according to the present invention, an additional roughening layer composed of one or more layers is provided on the upper layer of the vertical roughening layer, and preferably one additional roughening layer is provided. Due to the presence of the additional roughening layer, it is possible to impart resin adhesion at a level that cannot be achieved only by the conventional uneven roughening (see, for example, FIG. 6). This additional roughening layer is a portion that is roughened on the upper layer of the vertical roughening layer so that the distance between the peaks is narrower (smaller) than that of the vertical roughening layer. The additional roughened layer is formed to give a wedge action to the resin. It is preferable that the additional roughened layer has a portion formed at an angle of ± 20 ° or more from the 90 ° perpendicular line of the substrate as much as possible. That is, it is preferable that the additional roughened layer is more inclined with respect to the 90 ° perpendicular line of the substrate. As a result, not only the anchor effect is further increased, but also the expansion and contraction of the resin due to the high temperature environment and the high humidity environment can be followed not only two-dimensionally but also three-dimensionally. Adhesion will be improved. The additional roughened layer is preferably made of a material having good adhesion to the vertical roughened layer, and examples thereof include copper, copper alloys, nickel, nickel alloys, cobalt, cobalt alloys, silver and silver alloys. Among them, any of nickel, nickel alloy, cobalt, and cobalt alloy is preferable because it can also provide a function as a barrier layer for preventing the diffusion of the substrate component. The additional roughening layer is preferably composed of a component different from that of the vertical roughening layer. Copper alloys, nickel alloys, cobalt alloys, silver alloys include copper-tin alloys as copper alloys, nickel-zinc alloys as nickel alloys, cobalt-tin alloys as cobalt alloys, silver-tin alloys as silver alloys, etc. Can be mentioned.

(Film thickness of additional roughened layer)
The thickness of the additional roughened layer is not particularly limited, but the larger the film thickness, the larger the unevenness due to roughening tends to be. On the other hand, if it is too thick, there is a concern that the unevenness of the vertical roughening layer will be filled. Therefore, it is preferably 1/10 or more, preferably 1/5 or more of the vertical roughened layer coating thickness. On the other hand, the upper limit coating thickness of the additional roughened layer is preferably at most the same thickness as the coating thickness of the vertical roughened layer, and more preferably 2/3 or less of the vertical roughened layer thickness.

(Shape (thickness) of vertical roughening layer and additional roughening layer)
Further, since the shape of the roughened layer obtained in the present invention utilizes the wedge action of the additional roughened layer, the degree cannot be expressed by the roughness measurement from the surface. Therefore, the line segment length of the cross section of the outermost layer after the formation of all the film layers (each roughened layer described above) when observed from the cross section (total length of the line segment length of the cross section of the outermost layer) is measured. The value of the ratio of the cross section of the conductive substrate to the line segment length can be used as a length index. The value of the ratio (A / B) of the line segment length of the outermost layer cross section (the line segment length of the outermost layer cross section) (A) is preferably 1 when the line segment length (B) of the conductive substrate cross section is 1. Is 1.2 times or more, more preferably 2 times or more. As a result, the specific surface area is increased and the adhesion to the resin is increased. On the other hand, when the line segment length (B) of the cross section of the conductive substrate is set to 1, powder falls off when the value of the ratio (A / B) of the line segment length (A) of the outermost layer cross section exceeds about 4 times. It is preferably 4 times or less, and more preferably 3.5 times or less because there is an easy concern.
In the present invention, the vertical roughening layer and the additional roughening layer can improve the resin adhesion with the sealing material.

(Shape of each roughened layer)
In the present invention, since the vertical roughening layer and the additional roughening layer are formed, the unevenness of each cannot be grasped only by the measurement from the outermost layer, and the adjacent convexities of each roughening layer can be observed by observing from the cross section. It is possible to observe the apex spacing of the portions (unevenness of each roughened layer). This can be confirmed from the contrast of the crystal grain size by, for example, after processing an arbitrary roughened layer cross section with Focused Ion Beam: FIB and then scanning Ion Mycroscop: SIM image, and the adjacent convex portions of each roughened layer. The spacing between vertices can be determined from the scale. In each roughened layer, the average spacing between the vertices of the convex portions adjacent to each of the vertical roughened layer and the additional roughened layer is defined as "the interval between the vertical roughened layers (the interval between the convex portions)" and "the interval between the additional roughened layers". When we say "spacing (spacing of convex parts)", the spacing of the vertical roughening layer is different from that of the additional roughening layer. It is preferable that the spacing between the vertical roughening layers is larger than that of the additional roughening layers. As a result, the resin easily penetrates between the vertical roughening layers, so that the resin adhesion can be further improved. As for the ratio of the intervals, the interval of the additional roughening layer is preferably 1/2 or less, more preferably 1/4 or less of the interval of the vertical roughening layer. On the other hand, if it exceeds 1/20, the additional roughened layer becomes too fine and the adhesion is decreasing, so that it is preferably 1/20 or more, more preferably 1/15 or more. When there are a plurality of vertical roughening layers, the vertical roughening layer having the maximum interval is the target, and when there are a plurality of additional roughening layers, the addition formed on the outermost surface thereof is targeted. you a rough layer and its target.
In vertical roughened layer, by changing the current density and coating thickness, it can be controlled groaning spacing of the additional roughened layer crystal grain size of the roughened layer is changed. By rough-plating the roughened layers of different components, it is possible to control the change in the convex-convex spacing ratio. Specifically, the thickness and average spacing of each roughened layer can be narrowed as the current density increases and wider as the current density decreases.

(Conductive substrate)
Further, as the metal substrate (conductive substrate) component to be used, copper or copper alloy, iron or iron alloy, aluminum or aluminum alloy or the like is preferable, and copper or copper alloy having good conductivity is preferable.
For example, as an example of a copper alloy, "C14410 (Cu-0.15Sn, manufactured by Furukawa Denki Kogyo Co., Ltd., trade name: EFTEC (registered trademark) -3)", "C19400 (registered trademark)", which is an alloy published in CDA (Copper Development Association). Cu-Fe alloy material, Cu-2.3Fe-0.03P-0.15Zn) "," C18045 (Cu-0.3Cr-0.25Sn-0.5Zn, manufactured by Furukawa Denki Kogyo Co., Ltd., trade name) : EFTEC-64T) ”and the like can be used. The unit of the number before each element is mass%. Since these copper alloy substrates have different conductivity and strength, they are appropriately selected and used according to the required characteristics, but it is preferable to use a copper alloy strip having a conductivity of 50% IACS or more.
Further, as the iron or iron alloy, for example, 42 alloy (Fe-42 mass% Ni), stainless steel, or the like is used. These ferroalloy substrates are not very conductive, but do not require much conductivity and can be applied to lead frames for the purpose of transmitting electrical signals.
Further, as the aluminum or the aluminum alloy, for example, A5052 or the like is used.
The thickness of the substrate is not particularly limited, but is usually 0.05 mm to 2 mm, preferably 0.1 mm to 1 mm.

(Upper layer and surface layer of roughened plating)
Further, according to the present invention, in order to impart properties such as solder wettability, wire bonding property, and die bonding property of the lead frame to the upper layer (surface layer) of the additional roughening layer, a palladium, palladium alloy, rhodium, and rhodium alloy are provided. , Luthenium, ruthenium alloy, platinum, platinum alloy, iridium, iridium alloy, gold, gold alloy, silver, silver alloy, all or part of the lead frame material, with a single layer or multiple layers. It may be formed. Among these, typical layer configurations include Pd / Au coating, Pd / Ag / Au coating, Pd / Rh / Au coating, Ru / Pd / Au coating, and the like in order from the roughened layer side to the surface. There is no particular limitation on the coating thickness, but if it is too thick, it may fill the unevenness of the roughened layer and fail to function, or it may increase the cost because it is mainly composed of precious metals. In this document, "mainly precious metal" means that 50% by mass or more of the constituents are precious metals. From these, the total coating thickness is preferably 1 μm or less. Palladium alloys, rhodium alloys, ruthenium alloys, platinum alloys, iridium alloys, gold alloys, as silver alloys, palladium-silver alloys as palladium alloys, rhodium-palladium alloys as rhodium alloys, ruthenium-iridium alloys as ruthenium alloys, Examples of the platinum alloy include a platinum-gold alloy, an iridium alloy includes an iridium-lutenium alloy, a gold alloy includes a gold-silver alloy, and a silver alloy includes a silver-tin alloy.

(Coating part of roughened layer)
The roughened layer may be formed in at least a part of the resin-molded portion in the present invention. For example, the lead frame is preferably formed in an area of at least 1/5 or more of the resin-molded portion, and more preferably in an area of 1/2 or more, thereby exhibiting an effect of improving adhesion. Most preferably, it is applied to the entire surface to be resin-molded. The shape of the partially provided roughened layer can take various forms such as a stripe shape, a spot shape, and a ring shape. Further, in a product in which the resin mold has only one side, for example, it is possible to form the roughened layer on only one side.

Further, according to the present invention, since roughening plating can be controlled relatively easily by current density and stirring and is simple, either or both of the vertical roughening layer and the additional roughening layer are formed. It is preferable to form by an electroplating method. Further, it is more preferable to form both by wet plating from the viewpoint of productivity.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic cross-sectional schematic diagram according to an embodiment of the present invention. A vertical roughening layer 2 is formed on the upper layer of the conductive substrate 1, and an additional roughening layer 3 is formed on the upper layer thereof. The upper part of the additional roughening layer 3 is covered with a resin mold (not shown). In a product (semiconductor package) in which the resin mold has only one side as in this embodiment, for example, the roughened layer can be formed on only one side, or of course, it may be formed on both sides.

FIG. 2 is a schematic cross-sectional schematic view of another embodiment of the present invention. A vertical roughening layer 2 is formed on the upper layer of the conductive substrate 1, an additional roughening layer 3 is formed on the upper layer thereof, and the solder wettability, wire bonding property, and die bonding property of the lead frame are further formed on the surface layer thereof. A film layer made of any of palladium, palladium alloy, rhodium, rhodium alloy, ruthenium, ruthenium alloy, platinum, platinum alloy, iridium, iridium alloy, gold, gold alloy, silver, and silver alloy in order to impart such properties. (Surface layer) 4 is entirely formed of a single layer. The upper part of the film layer 4 is covered with a resin mold (not shown). The film layer 4 is a layer formed to impart properties such as solder wettability, wire bonding property, and die bonding property of the lead frame, and even if it is partially formed on a resin-molded portion, for example. Good. The shape may also be striped, spot-shaped, ring-shaped or the like.

FIG. 3 is a schematic cross-sectional schematic view of still another embodiment of the present invention. A vertical roughening layer 2 is formed on the upper layer of the conductive substrate 1, an additional roughening layer 3 is formed on the upper layer thereof, and the solder wettability, wire bonding property, and die bonding property of the lead frame are further formed on the surface layer thereof. A film layer made of any of palladium, palladium alloy, rhodium, rhodium alloy, ruthenium, ruthenium alloy, platinum, platinum alloy, iridium, iridium alloy, gold, gold alloy, silver, and silver alloy in order to impart such properties. 4'(first surface layer) and film layer 5 (second surface layer) are formed by two layers. The upper part of the film layer 5 is covered with a resin mold (not shown). At this time, the film layers 4'and 5 are formed from different metal species. For example, the film layer 4'is preferably Pd, Rh, Ru, Ir or the like, and the film layer 5 is preferably Au, Ag, Pt or the like. In FIG. 3, the film layers 4'and 5 are formed on the entire surface, but in order to reduce the amount of precious metal used, the film layers 4'and 5 are formed only on the parts that require actions such as wire bonding and soldering. By forming it, it is possible to take an environment-friendly and low-cost form by saving precious metals.

FIG. 4 is an enlarged view of a schematic cross-sectional view according to an embodiment of the present invention, in which a vertical roughening layer 2 is formed on an upper layer of a conductive substrate 1, and an additional roughening layer 3 is formed on the upper layer thereof. However, it is a schematic diagram which shows the interval 6 of the vertical roughening layer and the interval 7 of an additional roughening layer. As described above, the intervals (6 and 7 respectively) between the vertical roughening layer 2 and the additional roughening layer 3 are different. Further, it is preferable that the distance 7 between the additional roughening layers is smaller (narrower) than the distance 6 between the vertical roughening layers. This is because the resin to be molded enters the gap of the relatively large vertical roughening layer 2, and the additional roughening layer 3 formed by the present invention acts as a wedge against the resin, so that it is stronger than before. This is because it adheres to the resin, and as a result, the resin adhesion can be maintained even in harsh tests such as high temperature and high humidity.

FIG. 5 is an enlarged view of a schematic cross-sectional schematic view of the above embodiment shown in FIG. 4 of the present invention, in which a vertical roughening layer 2 is formed on an upper layer of a conductive substrate 1, and a vertical roughening layer 2 is formed on the upper layer thereof. FIG. 3 is a schematic view showing the conductive substrate cross-sectional line segment length 8 (B) and the surface layer cross-sectional line segment length 9 (A) of which the additional roughened layer 3 is formed. Here, the cross-sectional line segment length 9 of the outermost layer means the total length of the illustrated jagged length (the length 9a obtained by extending the jaggedness shown in FIG. 5). In the present invention, the total length 9a (A) of the cross-sectional line segment length of the outermost layer is divided by the cross-sectional line segment length 8 (B) of the conductive substrate, and the value of the ratio (A / B) (outermost layer). The specific surface area is increased by preferably 1.2 or more, more preferably 2 or more (the value of the ratio obtained by dividing the total length of the cross-sectional line segment length 9a (A) by the cross-sectional length 8 (B) of the conductive substrate). As a result, the adhesion with the resin is increased. On the other hand, if the value of the ratio of line segment lengths (A / B) exceeds about 4, there is a concern that powder may easily fall off, so the value of this ratio of line segment lengths (A / B) is preferable. It is 4 or less, more preferably 3.5 times or less.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Various conductive substrates shown in Table 1 having a plate thickness of 0.2 mm cut into a test piece size of 40 mm × 40 mm were prepared in advance, and after undergoing the pretreatment of the cathode electrolytic degreasing and pickling steps shown below, the invention example is vertical. A roughened layer and an additional roughened layer were formed. As a comparative example, after the vertical roughening layer was formed, a Ni layer was usually formed as an additional roughening layer. Further, as a conventional example, a roughened layer having only a roughened Ni layer formed was prepared. Further, as a further upper layer of each sample, 0.02 μm of Pd plating was formed on the upper layer of the additional roughening layer, and then 0.01 μm of Au plating was further formed on the upper layer to form the outermost layer. Examples 1 to 15 are the forms shown in FIG. Comparative Example 1 is a form shown in FIG. 6 in which the Cu base plating 12 is not provided. Conventional example 1 is the form shown in FIG. As for the thickness and average spacing of each roughened layer, the higher the current density, the narrower the spacing, and the lower the current density, the wider the spacing.
In the vertical roughened layer, the crystal grain size of the vertical roughened layer was changed by changing the current density and the coating thickness, and the convex-convex spacing of the additional roughened layer was controlled. The spacing (ratio) was controlled by changing the spacing between the convex and convex by rough-plating the layers of different components. The roughening thickness could be determined by the processing time, and the average interval could be created by the current density. Further, the outermost layer cross-sectional line segment length (total length of the outermost layer cross-sectional line segment length) (A) and the conductive substrate cross-sectional line segment length (B) are measured and their ratios (outermost surface layer cross-sectional line segment length) are measured. The value of (A / B) was obtained by dividing the total length 9a (A) of the above by the conductive substrate cross-sectional line segment length 8 (B). This is shown in the table as "surface cross-sectional line segment length ratio".

(Pretreatment conditions)
[Cathode electrolytic degreasing]
Solventing liquid: NaOH 60 g / liter Degreasing conditions: 2.5 A / dm ² , temperature 60 ° C, degreasing time 60 seconds [pickling]
Pickling solution: 10% Sulfate pickling conditions: 30 seconds, immersion, room temperature

(Roughened plating conditions)
[Roughened Cu plating (forms vertical roughened layer)]
Plating solution: Copper sulfate: Copper concentration 5-10 g / liter, Sulfate: 30-120 g / liter, Ammonium molybdate: 0.1-5.0 g / liter as Mo metal Plating conditions: Bath temperature 20-60 ° C, current Density 10-60A / dm ²
[Roughened Ni plating (forms roughened layer)]
Plating liquid: WDB-321 (trade name) manufactured by World Metal Co., Ltd.
Plating conditions: current density 8A / dm ² , temperature 70 ° C

(Normal intermediate plating conditions)
[Ni plating] (normally Ni plating)
Plating _{solution: Ni (SO 3 NH 2)} 2 · 4H 2 O 500g / l, NiCl ₂ 30 g / _l, H ₃ BO ₃ 30g / l Plating Conditions: current density 10A / dm ^2, temperature 50 ° C.

[Co plating (forming a roughened layer)]
Plating _{solution: Co (SO 3 NH 2)} 2 · 4H 2 O 500g / l, CoCl ₂ 30 g / _l, H ₃ BO ₃ 30g / l Plating Conditions: current density 10A / dm ^2, temperature 50 ° C.

(Pd plating conditions)
[Pd plating (forming the first surface layer)]
Plating solution: Pd (NH ₃ ) ₂ Cl ₂ 45 g / liter, NH ₄ OH 90 ml / liter, (NH ₄ ) ₂ SO ₄ 50 g / liter, Parasigma brightener (trade name, manufactured by Matsuda Sangyo Co., Ltd.) 10 ml / Liter plating conditions: current density 5A / dm ² , temperature 60 ° C

(Au plating conditions)
[Au plating (forming the second surface layer)]
Plating solution: KAu (CN) ₂ 14.6 g / liter, C ₆ H ₈ O ₇ 150 g / liter, K ₂ C ₆ H ₄ O ₇ 180 g / liter Plating conditions: Temperature 40 ° C

In the prepared test pieces of the invention example, the comparative example, and the conventional example, a pudding-like test piece having a contact area of 4 mm ² was formed by using a transfer mold test device (product name: Model FTS) manufactured by Kotaki Seiki Co., Ltd. for the resin mold. The test piece was put into a high temperature and high humidity test (85 ° C., 85% RH, 168 hours), and the test piece was evaluated for resin adhesion and the like. The results are shown in Table 1.

(Resin adhesion evaluation)
Evaluation resin: G630L, manufactured by Sumitomo Bakelite (trade name)
Evaluation conditions: Equipment: 4000Plus, manufactured by Nordson Advanced Technology (trade name),
Load cell: 50 kg
Measurement range: 10 kg
Test speed: 100 μm / s
Test height: 10 μm
"A" (excellent) if it is on average 10 kgf / mm ² or more, "B" (good) if it is 10 kgf / mm less than ² 5 kgf / mm ² or more on average, "D" (No) on average It is shown that the case is 0 kgf / mm ² or more and less than 5 kgf / mm ² .

(Evaluation of powder removal property)
Sensitivity evaluation was performed visually. "A" (excellent) is "D" when no powder drop is observed, "B" (good) is when powder drop occurs a little, and "C" (possible) is when powder drop occurs a little more. (Impossible) indicates that when a large amount of powder falling occurs. A to C are levels for practical use.

(Evaluation of average interval)
As the ratio of the spacing between the roughened layers, a convex portion of any arbitrary layer is determined in an image observed with a scanning electron microscope (SEM) from a vertical cross section, and 10 adjacent convex portions continuous to the right are defined. The convex spacing (peak spacing) was measured, and the ratio was calculated from the average value. Further, the interval ratio (applied / vertical) means a value obtained by calculating the ratio of the interval of the attached roughened layer to the interval of the vertically roughened layer. As shown in FIG. 4, the measurement of each convex-convex interval is performed by measuring the interval between the convex apex confirmed by the vertical cross-sectional observation and the adjacent convex apex (vertical roughening layer interval 6, roughening roughening). The "average spacing" is shown in Table 1 by taking the average value of the layer spacing 7). In addition, SEM observation was performed at each location divided into approximately 10 equal parts in the TD direction of the strip, and from the obtained SEM image, the line segment length of the cross section of the outermost layer (total length of the line segment length of the cross section of the outermost layer) (A). ) And the line segment length (B) of the conductive substrate cross section, and the ratio (the total length 9a (A) of the line segment length of the outermost layer cross section is the line segment length 8 (B) of the conductive substrate cross section. ) Divided by) (A / B). This is shown in the table as "surface cross-sectional line segment length ratio".

1 Conductive substrate 2 Vertical roughened layer 3 Attached roughened layer 4 Surface layer 4'First surface layer 5 Second surface layer 6 Vertical roughened layer spacing 7 Attached roughened layer spacing 8 Base cross-section length 9 Outermost surface layer cross section Length 9a Total length of outermost surface cross-sectional length 11 Conductive substrate (copper, copper alloy, iron, iron alloy, etc.)
12 Copper base plating layer 13 Nickel roughened plating layer 14 Surface layer (grown along the nickel roughened plating layer)

Claims (9)

In a lead frame material having a roughened layer on a conductive substrate, the roughened layer is composed of a plurality of roughened layers, and the roughened layer is a vertical coarse layer composed of at least one layer in the vertical direction of the conductive substrate. and has a layer further has its top in the additional roughened layer of vertical roughened layer at least one layer, among irregularities the vertical roughened layer and additional roughened layer has each of the additional roughened layer A lead frame material characterized in that the average distance between the vertices of adjacent convex portions is 1/20 or more and 3/4 or less of the average distance between the vertices of adjacent convex portions of the vertical roughening layer . The lead frame according to claim 1, wherein the value of the ratio (A / B) of the line segment length (A) of the outermost layer cross section to the line segment length (B) of the conductive substrate cross section is 1.2 or more and 4 or less. Material. The lead frame material according to claim 1 or 2, wherein the conductive substrate is copper or a copper alloy, iron or an iron alloy, or aluminum or an aluminum alloy. The plurality of roughened layers are composed of two layers, and have a first vertical roughened layer that is roughly roughened in the vertical direction of the conductive substrate, and a second additional roughened layer that is an upper layer of the vertical roughened layer. The lead frame material according to any one of claims 1 to 3, further characterized in that the components of the vertical roughening layer and the additional roughening layer are different. The lead frame material according to any one of claims 1 to 4 , wherein the component of the vertical roughening layer is made of copper or a copper alloy. The lead frame material according to any one of claims 1 to 5 , wherein the component of the additional roughened layer is made of any one of nickel, a nickel alloy, cobalt, and a cobalt alloy. The conductive substrate has a vertical roughened layer roughened in the vertical direction, an additional roughened layer as an upper layer of the vertical roughened layer, and a palladium-palladium alloy as an upper layer of the additional roughened layer. , Rhodium, rhodium alloy, ruthenium, ruthenium alloy, platinum, platinum alloy, iridium, iridium alloy, gold, gold alloy, silver, silver alloy on the surface layer of any of the following, all or part of the lead frame material. The lead frame material according to any one of claims 1 to 6 , wherein the lead frame material has one layer or a plurality of layers. The method for producing a lead frame material according to any one of claims 1 to 7 , wherein either or both of the vertical roughening layer and the additional roughening layer are formed by electroplating. A semiconductor package using the lead frame material according to any one of claims 1 to 7 .

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