JP2015226039A - Comb tooth-shaped heat radiation pin member, manufacturing method of the same, and heat radiation plate with pins - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pin member, suitable for mass production, effective for improving a degree of freedom for a sectional shape of a pin and pin disposition.SOLUTION: The comb tooth-shaped heat radiation pin member with pins is a press molded article formed by die-punching a plate-like blank of copper or a copper alloy. A plurality of pins 1 arranged side by side in a comb shape and a substrate 2 for holding the pins at root parts form an integral structure having no joining part. The comb tooth-shaped heat radiation pin member has an end face 3 to be joined by blazing to a base plate member of a heat radiation plate on a back side of the pins 1 of the substrate 2.

Description

  The present invention relates to a member having a plurality of heat dissipation pins, which is a component of a heat dissipation plate for cooling a heating element such as a semiconductor chip, and a method for manufacturing the member. Further, the present invention relates to a pin-equipped heat sink whose heat dissipating pin member is integrated with a base plate.

  Electronic components that generate a large amount of heat, such as power semiconductor chips, are cooled by releasing heat to the heat sink. In general, a separate heat sink is fastened to one side of the heat sink via thermal grease, which is a factor that hinders heat transfer because its thermal conductivity is lower than that of a metal material.

  As a method for solving this problem, there has been proposed a method of directly forming a heat radiating fin or pin on one surface of a heat radiating plate. For example, Patent Document 1 discloses a method of forming fins or pins on a heat sink by etching. However, it takes time and cost to form deep voids by etching, and it is not always easy to form a large number of fins and pins with high accuracy.

  As a direct forming method other than etching, a hot forging method or a cutting method can be considered. However, in hot forging, high-temperature heating above the recrystallization temperature is required to reduce deformation resistance during processing, so the material softens and the heat sink tends to run out of strength, and the extrusion pressure is made uniform. The height of fins and pins is difficult to make difficult, the shapes other than round pins are difficult to remove from the mold, and shape defects are likely to occur, and when removing burrs around parts and removing the surface oxide film There are problems such as a rough surface and a very short life of the mold. Also, in the cutting method, it is mainly difficult to make a round pin because it is a method of cutting with a blade, and copper materials are very difficult to manufacture, and copper materials are inferior in productivity because of high cutting resistance and high processing speed. There are problems such as high manufacturing costs.

  On the other hand, as seen in Patent Documents 2 to 5, a method of attaching a pin member prepared in advance to a plate-like member without using thermal grease has been proposed. In this case, since the pins are erected one by one, it is necessary to devise measures for ensuring the bonding strength between the individual pins and the plate-like member. For example, a method of using a pin on which a special base is formed so that adjacent pins fit together (Patent Document 2), a pin insertion hole is provided in a plate-like member, and the pin is caulked and brazed. The method (patent documents 3-5) to fix by the method etc. is employ | adopted. However, it takes a lot of labor to form a special base for each pin. In addition, it takes time and labor to assemble the pin accurately into the hole provided in the plate member. Furthermore, in the case of caulking, it is necessary to secure a space for using a dedicated caulking jig, and the pin interval cannot be reduced so much.

JP 2004-22914 A JP-A-4-199736 JP-A-9-203595 JP 2004-103734 A JP 2006-114688 A

Although heat dissipation pins are advantageous in terms of heat dissipation compared to plate-like fins, manufacturing a “heat dissipation plate with pins” in which a large number of heat dissipation pins are integrated on the plate surface of the base plate member is as described above. However, there are many problems in terms of productivity, securing of strength, dimensional accuracy, cost, etc., and there is no rational method for manufacturing a heat sink with pins suitable for mass production.
The present invention provides a heat dissipating pin component suitable for mass production and effective in improving the flexibility of the cross-sectional shape and pin arrangement of the pin, and with the pin, the pin has excellent strength and dimensional accuracy. It aims at providing a heat sink.

  The above-mentioned object is a press-molded product obtained by punching a copper or copper alloy plate-shaped material, and a plurality of pins juxtaposed in a comb-like shape and a base portion that supports these pins at the root portion have no joint portion. This is achieved by a comb-shaped heat radiation pin member that has an integral structure and has an end surface that is brazed to the base plate member of the heat radiation plate on the back surface side of the pin of the base portion. The end face is, for example, a “flat end face”. Moreover, the said end surface can be made into the end surface (punching end surface) as formed by punching. The “integrated structure without a joint” means an integrated structure that has not undergone a step of joining and integrating a plurality of members.

In the comb-shaped heat radiation pin member, the average pin length Lp _M defined in (A) below is, for example, 3.0 to 30.0 mm, and the average projected pin diameter Dp _M is, for example, 0.8 to 5.0 mm. The average pin aspect ratio Lp _M / Dp _M expressed by the ratio of the average pin length Lp _M and the average projected pin diameter Dp _M can be set to 0.6 to 37.5. The average projection pin gap Ap _M defined by (B) below is, for example, 1.0 to 5.0 mm.
(A) On the projection plane viewed in the punching direction, a reference line that is perpendicular to the thickness direction of the base plate members to be joined is set at an arbitrary position on the back surface side of the pin from the end face of the base, and from the reference line When the distance is called “height”, the number of pins is n, and the minimum height of the base between two adjacent pins is called “inter-pin height” between the pins, The difference between the height Hp of the pin Hp and the height between the adjacent pins (the higher pin height if the height between the pins on both sides is different) Hb is expressed as the value of the pin length Lp And the distance between two intersections of the line representing the 1/2 pin height (Hp−Hb) / 2 and the pin outline is defined as the “projection pin diameter Dp” of the pin, and the Dp of the n pins Is defined as “average projection pin diameter Dp _M ”.
(B) For two adjacent pins, the distance between the intersections of the line representing the central height of the common height region between the two pins and the contour line facing both pins is the “projection pin gap Ap” between the pins. And the average value of Ap at n−1 locations is defined as “average projection pin gap Ap _M ”. Here, n is the number of pins.
Here, the “punching direction” is a punching direction in a pressing process for punching a plate material, and corresponds to the plate thickness direction of the plate material. “Thickness direction of the base plate member to be joined” refers to the thickness direction of the base plate when it is assumed that the comb-shaped heat radiation pin member is disposed at a predetermined joining position on the surface of the base plate member via a brazing filler metal layer. Means.

In order to achieve a pin arrangement with high heat dissipation effect while maintaining good fluidity of the refrigerant in the pin heat sink, the pin gap ratio Rp defined by (C) below is 0.14 to 0.75. It is effective to apply a certain heat radiation pin member.
(C) The “pin gap ratio Rp” is determined by the following equation (1) using the number n of pins, the average pin interval Ap _M , and the average pin diameter Dp _M.
Rp = (n−1) Ap _M / [n · Dp _M + (n−1) Ap _M ] (1)

The minimum projected pin clearance Ap _MIN is defined by the following (D), the maximum projected pin gap Ap _MAX, the minimum projection pin clearance Ap _MIN is 0.8~2.5mm example, the maximum projected pin gap Ap _MAX The pin gap ratio Ap _MAX / Ap _MIN represented by the ratio of the minimum projected pin gap Ap _MIN may be in the range of 1.0 to 5.0, for example.
(D) The smallest value among the n−1 projection pin gaps Ap is defined as “minimum projection pin gap Ap _MIN ”, and the largest value is defined as “maximum projection pin gap Ap _MAX ”. Here, n is the number of pins.

  Further, in the present invention, a plurality of the comb-shaped heat radiation pin members are juxtaposed and joined to the back surface of the heating element mounting surface of the base plate member made of copper or copper alloy for mounting the heating element on the surface, and the flat plate Provided is a heat sink with a pin having a joining structure in which an end surface and a surface of a base plate member are in close contact with each other by brazing using a brazing material having a melting point of 300 to 600 ° C. The joining structure is formed, for example, by brazing using a brazing material made of Zn or a Zn—Al based alloy having an Al content of 0 to 10% by mass.

As a manufacturing method of the above-described comb-shaped heat radiation pin member, an intermediate product having a plurality of pins that are formed by punching a copper or copper alloy plate-like material and arranged in a comb-tooth shape and a base portion that supports these pins at the root portion Obtaining step,
A step of changing the cross-sectional shape of the pin by subjecting the intermediate product to one or more presses;
A manufacturing method is provided.

The comb-shaped heat radiation pin member according to the present invention formed by press-molding a copper or copper alloy plate material has the following merits.
(A) Productivity is high.
(B) The cross-sectional shape of the pin can be arbitrarily set such as a circle, an ellipse, or a polygon, and the pin length, pin diameter, and pin interval can also be arbitrarily set. Design of a heat sink having an efficient pin shape and pin arrangement in consideration of fluidity is facilitated.
(C) High dimensional accuracy and good surface properties to the extent that deburring is unnecessary.
(D) Since the pin has a flat end surface on the back side, good thermal conductivity can be obtained between the base plate member and the pin by brazing and joining the entire flat end surface portion to the surface of the base plate member of the heat sink. Can be ensured, and high bonding strength can be obtained.
(E) Since a plurality of pins are integrated, the assembly of the heat sink with pins is significantly facilitated as compared with the case where independent pins are attached to the base plate member one by one.
Moreover, the heat sink with a pin using this comb-tooth-shaped heat radiation pin member has the following merits.
(F) By arranging a plurality of comb-shaped heat radiation pin members having a predetermined pin arrangement on the surface of the base plate member, it is difficult to implement the conventional method in terms of productivity and cost. Pin shape and pin arrangement can be easily realized at low cost.
(G) By applying a brazing material made of Zn or a Zn-Al alloy having a relatively low melting point to the joining of the radiating pin members, the softening of the material due to the temperature rise at the time of manufacture is suppressed and the strength of the radiating plate is kept high. it can.

The figure which illustrated the shape of the comb-tooth-shaped radiation pin member by the trigonometric method. The front view for demonstrating the dimension parameter of a comb-tooth-shaped heat radiation pin member. The figure which looked at the pin installation surface side of the heat sink with a pin according to this invention in the plate | board thickness direction of the baseplate member. Sectional drawing which illustrated typically the cooling structure of the heat sink with a pin which provided the refrigerant | coolant flow path. Sectional drawing which illustrated typically the cooling structure of the heat sink with a pin which provided the refrigerant | coolant flow path. Sectional drawing which illustrated typically the cross-section of the power semiconductor unit which has a cooling structure using the heat sink with a pin according to this invention. The drawing substitute photograph which shows the external appearance of a comb-tooth type heat radiation pin member. The drawing substitute photograph which shows the external appearance of a baseplate member. Drawing substitute photograph showing appearance of heat sink with pin. The side view which illustrated the various shape seen in the base longitudinal direction of the comb-tooth-shaped heat radiation pin member. Sectional drawing which illustrated typically the cooling structure of the heat sink with a pin which provided the refrigerant | coolant flow path. The front view which illustrated the plate | board thickness direction of the baseplate member to join, and a reference line about the comb-tooth-shaped thermal radiation pin member which provided the curve.

[Comb teeth type heat radiation pin member]
In FIG. 1, the shape about an example of the comb-tooth-shaped heat radiation pin member according to this invention is shown by the trigonometric method. The comb-shaped heat radiation pin member 10 is formed by punching a copper or copper alloy plate material and press-molding it. FIG. 1A is a front view seen in the punching direction, FIG. 1B is a plan view seen in the longitudinal direction of the pin, and FIG. 1C is a side view seen in the longitudinal direction of the base. In this example, the number of pins 1 is 7, and pins 1 having a circular cross-sectional shape (so-called “round pins”) are arranged in a comb-like shape at equal intervals. One end of each pin 1 is connected by one base 2. (D) is the enlarged view of the part shown with the code | symbol A in FIG. As shown to (d), you may attach R to the base part to the base 2 of the pin 1 by press molding. Each pin 1 and the base portion 2 form an integral structure without a joint portion, and a comb-shaped heat radiation pin member 10 is formed. An end surface 3 is formed on the back side of the pin 2 of the base portion 2 to be brazed to the base plate member. The end face 3 illustrated in this figure is a “flat end face”. In the drawing, the longitudinal direction of the pin is indicated by reference numeral 4, the longitudinal direction of the base is indicated by reference numeral 5, and the punching direction is indicated by reference numeral 6. The punching direction 6 is a direction corresponding to the thickness direction of the plate material. Unless the pin is specially bent, the punching direction 6 is usually perpendicular to the longitudinal direction 4 of the pin and the longitudinal direction 5 of the base. Hereinafter, unless otherwise specified, the “front view” regarding the comb-shaped heat radiation pin member means a projection view of the comb-tooth heat radiation pin member viewed from an infinite viewpoint in the same punching direction as FIG. Further, the “side view” means a projection view viewed from a viewpoint at infinity in the longitudinal direction of the base similar to FIG.

  FIG. 10 illustrates several side views of the shape of the comb-shaped heat radiation pin member according to the present invention. (1), (5), (6) are those in which the projected width in the punching direction 6 is smaller in the pin 1 than in the base 2, and (2) is that in which the projected width in the punching direction 6 between the base 2 and the pin 1 is equal. In (3), (4), and (7), the projected width in the punching direction 6 is larger for the pin 1 than for the base 2.

FIG. 2 exemplifies a front view of a comb-shaped heat radiation pin member (projected view seen from a point of view at infinity in the punching direction) for explaining the dimensional parameters used in the present specification. In this projection plane, there is an end face 3 that is brazed to the base plate member on the back side of the pin 1 in the base portion 2. A reference line a that is perpendicular to the thickness direction of the base plate to be joined is set at an arbitrary position on the back side of the pin 1 from the end face 3. In this figure, the end surface 3 is flat, and the reference line a is a straight line parallel to the end surface 3. When the comb-shaped heat radiation pin member is brazed and joined to a base plate member that has been previously warped, a comb tooth heat radiation pin member having a curvature that matches the warp shape of the base plate member is applied. In the comb-shaped heat radiation pin member to which such a curve is given, the reference line a is a curve reflecting the curve (see FIG. 12 described later). A concave portion 7 or a convex portion 8 may be provided on the back side of the pin 1. The distance from the reference line a is called “height”. In FIG. 2, the reference height is indicated as H ₀ . The number n of pins 1 is eight in this figure. The numbers (1) to (8) are assigned to the pins from the left, and the numbers [1] to [7] are assigned between the pins. The minimum height of the base projection surface between two adjacent pins is called the “inter-pin height” between the pins.

For a certain pin, the difference Hp−Hb between the reference surface height Hp at the tip of the pin and the inter-pin height between adjacent pins (the higher inter-pin height if the height between the pins on both sides is different) Hb Is defined as “pin length Lp”. For example, the pin length Lp (1) of the pin ₍₁₎ is Hp ₍₁₎ −Hb _[1] . The pin length Lp (2) of the pin ₍₂₎ is Hp ₍₂₎ −Hb _[1] . Since Hb _[1] = Hb _[2] , Lp ₍₂₎ is equal to Hp ₍₂₎ -Hb _[2] . As for the pin length Lp ₍₃₎ of the pin (3), the height between the pins on both sides is different from Hb _[2] <Hb _[3] , so the higher Hb _[3] is adopted, and Lp ₍₃₎ is Hp ₍₃₎ -Hb _[3]

For a pin, the distance between the two intersections of the line representing the 1/2 pin height (Hp−Hb) / 2 and the pin contour is defined as the “projection pin diameter Dp” of the pin. For example, in the case of the pin (1), the intersections of the line b representing the 1/2 pin height (Hp ₍₂₎ -Hb _[1] ) / 2 and the contour line c of the pin (1) are x ₁₁ and x _12. the present two points, and their x ₁₁ and x ₁₂ projecting pin diameter Dp of the pin (1) the distance _(1). Similarly, in the case of the pin (4), the intersections of the line d representing the 1/2 pin height (Hp ₍₄₎ −Hb _[4] ) / 2 and the contour line e of the pin (4) are x ₄₁ and x _42. the present two points, and the projection pin diameter Dp of the pin a distance x ₄₁ and _{x 42 (4) (4)} . The average value of the projected pin diameters Dp of the pins thus determined is determined as the “average projected pin diameter Dp _M ” of the comb-shaped heat radiation pin member. In the example of FIG. 2, a value obtained by dividing the sum of the projection pin diameters Dp _{(1) to} Dp _{( 8) by} the number of pins n = 8 is the average projection pin diameter Dp _M.

For the pin between two adjacent pins, the distance between the intersections of the line representing the center height of the common height region of both pins and the contour line facing both pins is expressed as “projection pin between the pins. It is defined as “Gap Ap”. For example, in the inter-pin [4] sandwiched between the pin (4) and the pin (5), both pins are respectively pinned over the entire length Hb _{[4] to} Hp ₍₄₎ and Hb _{[4] to} Hp _(5). The same height region exists. Therefore, the center height of the height region is (Hp ₍₄₎ -Hb _[4] ) / 2 = (Hp ₍₅₎ -Hb _[4] ) / 2, and the line d representing the center height and both the intersections of the contour e and f of opposed pins is x ₄₂ and x ₅₁ respectively, between the pins the distance between the x ₄₂ and x ₅₁ to [4] projecting pin gap Ap _[4] of. On the other hand, in the inter-pin [6] sandwiched between the pin (6) and the pin (7), the height region of the pin (6) is Hb _{[5] to} Hp ₍₆₎ and the height region of the pin (7). Hb _{[6] to} Hp ₍₇₎ , and a common height region where both pins exist (that is, a height region in which the horizontal distance between both pins can be assumed) is Hb _{[5] to} Hp _{(7 )} Is limited. Therefore, the center height of the height region is (Hp ₍₇₎ -Hb _[5] ) / 2, and the intersection of the line g representing the center height and the contour lines h and i facing both pins is respectively a x ₆₂ and x _71, and the projection pin gap Ap _[6] of the distance x ₆₂ and x ₇₁ between pins [6]. The average value of the projection pin interval Ap between the pins thus determined is determined as “average projection pin gap Ap _M ” of the comb-shaped heat radiation pin member. In the example of FIG. 2, a value obtained by dividing becomes average projected pin gap Ap _M by the number n-1 = 7 between pin sum of the projected pin gap _{Ap [1] ~Ap [7]} . In the present specification, the smallest value among the n−1 projection pin gaps Ap is defined as “minimum projection pin gap Ap _MIN ”, and the largest value is defined as “maximum projection pin gap Ap _MAX ”.

In FIG. 12, the front view which described the reference line of the comb-tooth-shaped heat radiation pin member which provided the curve is illustrated. In the drawing, the cross-sectional shape of the base plate member 20 at the center position in the punching direction of the base portion 2 when the comb-shaped heat radiation pin member is disposed via the brazing filler metal layer 11 at a predetermined joining position of the base plate member 20 is indicated by a broken line. It is shown by. The base plate member 20 is warped in advance, and the comb-shaped heat radiation pin member is also curved in advance to match the warp shape. The plate thickness direction 9 of the base plate member 20 to be joined varies depending on the location depending on the warp shape. In this case, a curve that is always perpendicular to the plate thickness direction 9 is adopted as the reference line a. The position parameters of the reference line a in the plate thickness direction 9 are defined as “reference height H ₀ ”, and the distance from the reference line a is defined as “height”. In FIG. 12, the magnitude of the warpage (degree of curvature) is exaggerated.

As will be described later, a plurality of comb-shaped heat radiation pin members according to the present invention are brazed to the surface of the base plate member as a set to constitute a heat radiation plate with pins. The pin portion is exposed to the flow of a liquid refrigerant such as water, and is responsible for heat transfer from the heat sink to the refrigerant. In heat dissipation applications for electronic parts, it is usually desirable to set the average pin length Lp _M in the range of 3.0 to 30.0 mm and the average projected pin diameter Dp _M in the range of 0.8 to 5.0 mm. In many cases, Lp _M may be in the range of 5.0 to 15.0 mm, and Dp _M may be in the range of 1.0 to 3.0 mm. If the average case pin length Lp _M is too small or average projected pin diameter Dp _M is too large, no sufficient heat dissipation effect. On the contrary, when the average pin length Lp _M is excessive or when the average projected pin diameter Dp _M is excessively small, the pin strength is insufficient or the thermal conductivity toward the pin tip tends to be insufficient. The average aspect ratio Lp _M / Dp _M of the pins may be set in the range of 0.8 to 37.5, but it is more effective to set it to 1.5 to 20.0. The average projection pin gap Ap _M is preferably 1.0 to 5.0 mm. As Ap _M decreases, the flow resistance of the liquid refrigerant increases, and conversely, heat dissipation decreases as Ap _M increases.

  The layout of the plurality of comb-shaped heat radiation pin members arranged in parallel on the base plate member can be considered in various modes depending on the design of the heat dissipation device. However, considering both the reduction of the refrigerant flow resistance and the securing of heat dissipation, the average flow direction of the refrigerant (specifically, for example, in the examples of FIGS. 4 and 5 described later, the refrigerant is placed on the pin side of the base plate member 20). The arrangement of the pins as viewed in the direction from the refrigerant inlet 32 to the refrigerant outlet 33 of the cooling jacket 31 provided for forming the flow path is important. If the average interval between adjacent pins through which the refrigerant passes is too narrow, the flow resistance becomes excessive, and conversely, if it is too wide, the heat dissipation is reduced. Therefore, each comb-shaped heat radiation pin member is prepared with a pin arrangement in which the pin interval (pin density) in the base longitudinal direction (reference numeral 5 in FIGS. 1 and 2) is optimized, and the base lengths thereof. The direction of the hand is close to the direction perpendicular to the flow direction of the refrigerant (specifically, for example, the angle between the average flow direction of the refrigerant and the longitudinal direction of the base is 90 ° ± 45 °) ) If a method of juxtaposing on the surface of the base plate member is adopted, a desired pin arrangement considering the refrigerant flow resistance and heat dissipation can be easily realized.

The inventors have studied various pin arrangements of comb-shaped heat radiation pin members suitable for realizing such pin arrangement. As a result, it has been found that it is effective to apply a radiating pin member having a pin gap ratio Rp defined by (C) below of 0.14 to 0.75. Those having Rp of 0.25 to 0.50 are more suitable targets.
(C) The “pin gap ratio Rp” is determined by the following equation (1) using the number n of pins, the average pin interval Ap _M , and the average pin diameter Dp _M.
Rp = (n−1) Ap _M / [n · Dp _M + (n−1) Ap _M ] (1)
If the pin gap ratio Rp is too small, for example, the flow resistance when the comb-shaped heat radiation pin members are arranged so that the angle between the average flow direction of the refrigerant and the longitudinal direction of the base is 90 ° ± 45 ° is excessive. It is easy to become. On the other hand, if the pin gap ratio Rp is too large, it is difficult to obtain sufficient heat dissipation.

In addition, in order to more efficiently achieve both reduction of the refrigerant flow resistance and securing of heat dissipation, the pin density in the portion corresponding to the back of the electronic component mounting position in the center of the base plate member is increased, and the pins in the peripheral portion thereof are increased. A pin arrangement that lowers the density is effective. In such a case, each comb-shaped heat radiation pin member is prepared with a pin arrangement in which the pin interval is small near the center and large near both ends in the longitudinal direction of the base (reference numeral 5 in FIGS. 1 and 2). The base longitudinal direction is close to the direction perpendicular to the refrigerant flow direction (specifically, for example, the angle formed between the average refrigerant flow direction and the base longitudinal direction is 90 ° ± 45). By arranging them side by side on the surface of the base plate member, the desired pin arrangement can be easily realized. In this case, it is effective to set the pin gap ratio Rp as described above. Further, with respect to the minimum projection pin gap Ap _MIN and the maximum projection pin gap Ap _MAX defined in the following (D), the minimum projection pin gap It is effective to set Ap _MIN to 0.8 to 2.5 mm and pin gap ratio Ap _MAX / Ap _MIN to a range of 1.0 to 5.0. In particular, the minimum projection pin gap Ap _MIN may be controlled to 1.0 to 2.0 mm, and the pin gap ratio Ap _MAX / Ap _MIN may be managed to 1.5 to 3.0.
(D) The smallest value among the n−1 projection pin gaps Ap is defined as “minimum projection pin gap Ap _MIN ”, and the largest value is defined as “maximum projection pin gap Ap _MAX ”. Here, n is the number of pins.
In addition, since it is possible to arrange a desired pin by adjusting the width of the base and the shape of the pin, an angle other than the angle 90 ° ± 45 ° formed by the average flow direction of the refrigerant and the longitudinal direction of the base ( For example, 0 °) is not excluded.

  The material of the comb-shaped heat radiation pin member is preferably copper or a copper alloy having a conductivity of 70% IACS or more, more preferably 85% IACS or more. If the thermal conductivity is defined, it is preferable that the thermal conductivity near room temperature (5-35 ° C.) is 300 W / (m · K) or more, more preferably 350 W / (m · K) or more. From the viewpoint of heat conduction, oxygen-free copper (alloy number C1020 of JIS H3100) is advantageous, but considering the strength, the purity of a small amount of alloy elements such as Fe, Ni, Sn, Zn, and P is 99.9%. It is desirable to use level copper material.

  The comb-shaped heat radiation pin member according to the present invention can be obtained by punching and pressing a copper or copper alloy plate material. Specifically, first, an intermediate product having a plurality of pins that are punched from a copper or copper alloy plate-like material and arranged in a comb-like shape and a base portion that supports these pins at the root portion is obtained. In this intermediate product, the punching direction corresponds to the plate thickness direction of the plate material, and the longitudinal direction of the pin and the longitudinal direction of the base are both parallel to the plate surface of the plate material, that is, the punching direction (the plate thickness of the material). Direction). The end surface on the back surface side of the pin is a surface for brazing and joining to the surface of the base plate member. If necessary, the concave portion 7 and the convex portion 8 shown in FIG. 2 may be formed on the back surface side of the pin. However, in order to ensure sufficient thermal conductivity between the base plate member and the comb-shaped heat radiation pin member, the flat end surface serving as the brazed joint surface is 80% or more of the length in the longitudinal direction of the base, and further 90% or more. It is desirable to occupy.

  About the intermediate product after the punching, the pin portion corresponding to the comb teeth is pressed to adjust the cross-sectional shape of the pin. According to the press working, a round pin having a circular cross section can be produced with high accuracy. If a predetermined mold is used, a pin having an elliptical cross section or a polygonal cross section can be formed. When brazing and joining to a flat base plate member that has not been warped, the longitudinal direction of the pin and the longitudinal direction of the base are generally perpendicular, and the longitudinal direction of the pin and the longitudinal direction of the base Are finished in a shape perpendicular to the punching direction (the thickness direction of the material). When brazing and joining to a flat base plate member that has not been warped, the base is usually not bent and the brazed joint surface of the base is a flat end face. In this case, the base longitudinal direction (reference numeral 5 in FIGS. 1 and 2) is uniform in any part of the base. On the other hand, when brazing and joining to a base plate that has been warped in advance, the base is also curved in accordance with the warped shape of the base plate. As a method for imparting curvature, a method of punching into a curved shape or a method of bending after punching can be applied. Usually, since the longitudinal direction of the pin is made to coincide with the thickness direction of the base plate, in the comb-shaped heat radiation pin member to which the curve is given, both the longitudinal direction of the pin and the longitudinal direction of the base portion change depending on the position of the base portion. The “base longitudinal direction” at a position where the base is located is a direction perpendicular to the thickness direction of the base plate viewed from that position. The said end surface used as a brazing joining surface has smoothness which can join the whole surface to a baseplate member by brazing. Even an end face that has been punched into a flat shape can usually be subjected to brazing without maintenance without deburring.

[Heat sink with pin]
FIG. 3 illustrates a view in which the pin installation surface side of the heat sink with pins according to the present invention is viewed in the thickness direction of the base plate member. In this example, two types of comb-shaped heat radiation pin members 10 having different pin arrangements are alternately arranged in the center of the surface of the base plate member 20 to form a pin group having a dual pin arrangement. The longitudinal direction of each pin 1 is perpendicular to the plate surface of the base plate member 20 (that is, parallel to the plate thickness direction). Each comb-shaped heat radiation pin member 10 has a flat end surface (reference numeral 3 in FIGS. 1 and 2) on the back side of the pin 1 of the base portion 2, and the end surface and the surface of the base plate member 20 have a melting point of 300 to 600 ° C. A heat sink 30 with a pin is formed by brazing using a brazing material, and the base plate member 20 and each comb-shaped heat radiation pin member 10 are integrated. That is, the pin-equipped heat sink 30 according to the present invention is constituted by the comb-shaped heat dissipating pin members 10, the base plate member 20, and the brazing material layer of the brazed joint portion. A substrate on which a heat generating component such as a power semiconductor is mounted is attached to the back surface of the pin group of the pin-equipped heat sink 30.

  The material of the base plate member 20 is preferably copper or a copper alloy having a normal-temperature conductivity of 70% IACS or more, more preferably 85% IACS or more, like the comb-shaped heat radiation pin member 10. If the thermal conductivity is defined, it is preferable that the thermal conductivity near room temperature (5-35 ° C.) is 300 W / (m · K) or more, more preferably 350 W / (m · K) or more. From the viewpoint of heat conduction, oxygen-free copper (alloy number C1020 of JIS H3100) is advantageous, but considering the strength, the purity of a small amount of alloy elements such as Fe, Ni, Sn, Zn, and P is 99.9%. It is desirable to use level copper material. The base plate member 20 and the comb-shaped heat radiation pin member 10 do not necessarily need to be made of the same kind of copper or copper alloy.

  For accurate and easy positioning during brazing, the base plate member 20 has a counterbore of a size that fits the bases 2 of the plurality of comb-shaped heat radiation pin members 10 arranged side by side (a flat surface having a step difference from the surroundings). It is effective to form a depression having a bottom surface in advance. In addition, concave portions and convex portions as indicated by reference numerals 7 and 8 in FIG. 2 are formed in the base portion 2 of the comb-shaped heat radiation pin member 10, and the surface of the base plate member 20 is also fitted into the concave portions and convex portions. It is also effective to form protrusions, grooves, holes and the like.

  As the brazing material, it is preferable to use a brazing material having a melting point of 600 ° C. or lower. A brazing material having a melting point of 500 ° C. or lower is more preferable, and a brazing material having a melting point of 450 ° C. or lower is more preferable. It is extremely effective to apply a sheet of Zn or Zn-Al alloy having an Al content of 0 to 10% by mass. Since the melting point of general silver brazing is around 780 ° C., the brazing temperature becomes higher, the copper or copper alloy material of the base plate member 20 and the comb-shaped heat radiation pin member 10 is easily softened, and deformation due to refrigerant pressure is a problem. It may become. On the other hand, joining with tin solder softens or melts the solder joint portion of the comb-shaped heat radiation pin member 10 when a semiconductor component is attached by soldering in a later step. On the other hand, since Zn or Zn—Al alloy having an Al content of 0 to 10% by mass has a melting point of around 400 ° C., significant softening of the copper or copper alloy material does not occur. In particular, a Zn—Al-based alloy having an Al content of 2 to 8 mass%, the balance Zn and inevitable impurities is preferable because of its low melting point. Even in this case, there is no problem because the brazing material layer is softened or melted at the time of soldering in the subsequent process. The sheet thickness of the brazing material may be 0.1 to 0.8 mm. The melting point of the brazing material may be higher than the soldering temperature in the subsequent step, but for example, a brazing material having a melting point of 300 ° C. or higher is preferably selected, and a melting point of 330 ° C. or higher is more preferable.

  FIG. 4 schematically illustrates a cooling structure in which a refrigerant flow path is provided in a heat sink with pins according to the present invention. This corresponds to a cross-sectional view cut across the pin in a plane parallel to the base plate member 20. A cooling jacket 31 having a refrigerant inlet 32 and a refrigerant outlet 33 is joined to the base plate member 20 so as to cover the pin group, and a refrigerant flow path is formed in the internal space of the cooling jacket 31. The refrigerant introduced from the refrigerant inlet 32 in the direction of the arrow flows through the cooling jacket 31 while receiving heat by contacting each pin 1 and is discharged from the refrigerant outlet 33 in the direction of the arrow. Usually, water may be used as the refrigerant. The cooling jacket 31 and the base plate member 20 are attached through packing or the like so as to maintain airtightness, or are joined by brazing. In FIG. 4, the base longitudinal direction 5 of each comb-shaped heat radiation pin member 10 and the average flow direction 34 of the refrigerant are indicated by arrows. The flow resistance of the refrigerant is greatly affected by the pin arrangement viewed from the average flow direction 34 of the refrigerant. In the example of this figure, since the base longitudinal direction 5 of the comb-shaped heat radiation pin member 10 and the average flow direction 34 of the refrigerant are substantially perpendicular to each other, the flow of the comb-tooth heat radiation pin member 10 is adjusted by adjusting the pin arrangement of each comb-tooth heat radiation pin member 10. Resistance can be easily controlled.

  FIG. 5 schematically illustrates a cooling structure in which a refrigerant flow path is provided in a heat sink with pins according to the present invention, as in FIG. In this example, the density of the pins 1 as viewed from the average flow direction 34 of the refrigerant is increased at the center of the base plate member 20. In this case, it is possible to increase the heat conduction efficiency in a portion located behind the heating element mounting position such as a semiconductor chip and to reduce the flow resistance of the refrigerant. Such a unique pin arrangement pattern can also be easily realized by adjusting the pin arrangement in each comb-shaped heat radiation pin member 10.

  FIG. 11 schematically illustrates a cooling structure in which a refrigerant flow path is provided in a heat sink with pins according to the present invention, as in FIG. In this example, two types of comb-shaped heat radiation pin members 10 are arranged in parallel so that the base longitudinal direction 5 is parallel to the average flow direction 34 of the refrigerant, and the same pin arrangement as that in FIG. 4 is realized. In this case, the comb-shaped heat radiation pin member 10 combines two types of shapes appearing in the side view, the type shown in FIG. 10 (1) and the type shown in FIG. 10 (4). Compared with FIG. 4, the number of the comb-tooth-shaped heat radiation pin members 10 required is small. However, for example, as shown in FIG. 5, when realizing a pin arrangement in which the density of the pins 1 as viewed from the average flow direction 34 of the refrigerant is increased at the center portion of the base plate member 20, there are many types of comb-shaped heat radiation pins. The member 10 needs to be prepared.

  FIG. 6 schematically illustrates a cross-sectional structure of a power semiconductor unit having a cooling structure using a heat sink with pins according to the present invention. This corresponds to a cross-sectional view of the power semiconductor unit having the cooling structure shown in FIG. 4 taken along the line AA in FIG. A counterbore is provided on the surface of the base plate member 20 on the pin 1 side, and the base portions 2 of the comb-shaped heat radiation pin members 10 are accommodated side by side in the counterbore of the base plate member 20 and the brazing material layer 11 is interposed therebetween. A spliced joint is formed. The pin-mounted heat sink 30 includes the base plate member 20, the brazing material layer 11, and each comb-shaped heat sink pin member 10. The cooling jacket 31 is attached to the base plate member 20 so as to maintain airtightness. The description of the mechanism (packing, brazing material layer, etc.) for maintaining the airtightness was omitted. A heat radiating copper plate 45, an aluminum nitride insulating substrate 42, a circuit copper plate 46, and a semiconductor chip 41 are mounted on the surface on the back side with respect to the pins 1 of the base plate member 20. The heat-dissipating copper plate 45 and the circuit copper plate 46 are integrated with the aluminum nitride insulating substrate 42 via the active metal-containing Ag—Cu brazing material layer 47, and this integrated structure (copper-clad aluminum nitride insulating substrate) is used for heat dissipation. The surface on the copper plate 45 side is joined and attached to the surface of the base plate member 20 via the solder layer 43. A semiconductor chip 41 is attached to the surface of the circuit copper plate 45 via a solder layer 43. Good heat conduction is realized from the base plate member 20 to the surface of each pin 1 by an integral structure made of a metal material. In addition, the cross-sectional shape of the pin 1 and the design freedom of pin arrangement are high, and in particular, it is easy to realize a high-density pin arrangement. Therefore, compared to conventional heat dissipation structures using cooling fins and cooling pins, Easy to implement efficient cooling.

[Example 1]
As a plate-like material, DSC-3N, 1 / 2H material (manufactured by DOWA Metal Co., Ltd., in mass%, Fe, Ni, Sn, P total is 0.1%, remaining Cu, conductivity 88% IACS, thermal conductivity A copper plate having a plate thickness of 2.0 mm made of 361 W / (m · K) was prepared. The copper plate was subjected to press punching and press working to produce a press-formed product of a comb-shaped heat radiation pin member having a shape as shown in FIG.
The press process is a first press process in which the cross section of the pin is rectangular, the pin length and the pin interval are uniform, the pin length is 10.0 mm, and the length of one side of the rectangular press direction is 2. The length of the other side is 1.6 mm, the distance between the pins is 2.9 mm, the number of pins is 9, and the base of the pin is 1 mm in height and 37.6 mm in width. It was pressed to become. The back side of the base pin was flat.
Next, the 2nd press work which makes the cross-sectional shape of a pin circular is performed. Each of the upper mold and the lower mold of the mold has a shape having a substantially semicircular cross section so that the pin can be accommodated, and the cross section of the pin is rounded by pressing with the upper and lower molds. The press working was performed at room temperature by a progressive feeding method, and comb-shaped heat radiation pins with nine pins were produced. A comb-shaped heat radiation pin having eight pins was produced by the same pressing process.
In this way, two types of comb-shaped heat radiation pin members having 9 and 8 pins were prepared. In both types, the cross-section of the pins is circular, the pin diameter, the pin length, and the pin interval are uniform, the average pin length Lp _M : 10.0 mm, the average projection pin diameter Dp _M : 1.6 mm, and the average projection pin gap Ap _M : 2.9 mm (all are common). One of the pin gap ratios Rp determined by the equation (1) is 0.62 and the other is 0.61. The end face of the base on the back side of the pin has a flat finish (no care such as deburring) as it is punched. The pin portion was formed into a round pin by press molding. In FIG. 7, the external appearance photograph of the comb-tooth-type heat radiation pin member used here is shown.

  On the other hand, a 137.6 mm × 106.6 mm base plate member was produced from a DSC-3N, 1 / 2H copper plate having a thickness of 3.0 mm. A counterbore portion 70 mm × 37.6 mm having a flat bottom surface with a depth of 1.0 mm was formed by milling at the center of the surface on one side. FIG. 8 shows a photograph of the appearance of the base plate member used here.

  As the brazing material, a brazing material sheet having a melting point of about 400 ° C. and having a thickness of 0.4 mm made of a Zn—Al-based alloy with 95% by mass of Zn and 5% by mass of Al was prepared. The brazing material sheet was laid on the entire surface of the counterbore bottom surface of the base plate member, and the two types of comb-shaped heat radiation pin members were alternately arranged on the counterbore portion thereon. With a comb made of stainless steel, each comb-shaped radiating pin member is pressed against the surface of the base plate member so as to maintain an accurate positional relationship, and brazed at a maximum temperature of 480 ° C. in a vacuum furnace. A heat sink was obtained. In FIG. 9, the external appearance photograph of the heat sink with a pin obtained here is shown. This means that 18 comb-type heat radiation pin members with 8 pins and 17 comb-type heat radiation pin members with 9 pins will be used as the base plate member. It is in contact.

  The obtained heat sink with pins was subjected to warping in the opposite direction in order to cancel out the “warping” generated during soldering, and then subjected to electroless nickel plating. As shown in FIG. 6, a structure in which a heat radiating copper plate 45, an aluminum nitride insulating substrate 42, and a circuit copper plate 46 are integrated through an active metal-containing Ag—Cu brazing material layer 47 is used. The surface on the back side with respect to the pins was soldered with tin solder of Ag: 3 mass%, Cu: 0.7 mass%, and remaining Sn. A semiconductor chip 41 as a heat source is mounted on the surface of the circuit copper plate 46 via a solder layer 43. Thereafter, the cooling jacket 31 and the cover 44 were attached. The cooling jacket 31 was attached in an airtight structure using a packing, and a refrigerant flow path was formed.

(Heat dissipation test)
Water was used as a coolant and passed through the cooling jacket 31. The temperature of the water introduced into the cooling jacket 31 was controlled to be constant by a temperature controller, and the water supply pressure was also constant. A constant current load was applied to the semiconductor chip using a test electronic circuit, the temperature change on the surface of the semiconductor chip was measured with a thermocouple (see FIG. 6, reference numeral 51), and the heat dissipation performance was evaluated according to the following criteria. The temperature of water introduced into the cooling jacket 31, the water supply pressure, and the current load applied to the semiconductor chip are common in the following examples unless otherwise specified.
(Double-circle): It will be in a steady state in the range whose surface temperature of a semiconductor chip is 100 degrees C or less.
◯: A steady state is obtained when the surface temperature of the semiconductor chip is in the range of 100 ° C. to 120 ° C.
(Triangle | delta): It will be in a steady state in the range whose surface temperature of a semiconductor chip exceeds 120 degreeC and 140 degrees C or less.
X: The surface temperature of the semiconductor chip exceeds 140 ° C.
Under this test condition, if it is Δ, it can be determined that it has practical heat dissipation. ○ Evaluation has better heat dissipation than that, and ◎ Evaluation means extremely excellent heat dissipation.

(Airtightness test)
A case that simulates a cooling jacket (with no refrigerant inlet and refrigerant outlet and an air introduction pipe) on a heat sink with pins of the same specifications as above (finished with warping and nickel plating), and the cooling jacket It was attached in the same way. This pin-mounted heat sink is submerged in 300 mm deep water from an air inlet pipe with a gauge pressure of 200 kPa, and held for a maximum of 10 minutes. Examined. If no air leakage is observed under these test conditions, it is determined that the product exhibits good airtightness.

  In this example, the heat dissipation was: ○ evaluation, and the air tightness: ○ evaluation.

[Example 2]
DK-3, 1 / 2H material (mass% Fe: 0.20%, Sn: 0.07%, Ni: 0.15%, P: 0.06%, balance Cu, conductivity) The test was performed under the same conditions as in Example 1 except that a copper alloy plate having 75% IACS and thermal conductivity of 313 W / (m · K) was used. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

Example 3
The same as in Example 1 except that the material of the base plate member is a copper plate of C1020, 1 / 2H material (99.96 mass% Cu, conductivity 101% IACS, thermal conductivity 391 W / (m · K)) The test was conducted under conditions. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

Example 4
The test was performed under the same conditions as in Example 1 except that the material of the comb-shaped heat radiation pin member was a C1020, 1 / 2H copper plate. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

Example 5
The test was performed under the same conditions as in Example 1 except that both the material of the comb-shaped heat radiation pin member and the material of the base plate member (base plate) were C1020 and 1 / 2H copper plates. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

Example 6
The test was performed under the same conditions as in Example 1 except that the brazing material was a Zn: 100% by mass zinc brazing sheet having a melting point of about 419 ° C. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

Example 7
The test was performed under the same conditions as in Example 1 except that the brazing material was a Zn—Al alloy sheet having a melting point of about 380 ° C. of Zn: 90 mass% and Al: 10 mass%. As a result, the heat dissipation was: ○ evaluation, and the airtightness: ○ evaluation.

[Comparative Example 1]
Example 1 except that the material of the base plate member (base plate) is C1020, 1 / 2H material, and the brazing material is silver solder with a melting point of about 770 ° C. Ag: 72 mass% and Cu: 28 mass% The test was conducted under the following conditions. As a result, the heat dissipation was: o evaluation, and the airtightness: x evaluation.
Since the material of the base plate member is C1020, the strength level is relatively low and the temperature of the silver brazing is as high as 800 ° C., so that the base plate member is softened. Therefore, the strength of the obtained heat radiating plate with the pin was lowered, and air leakage occurred due to the deformation of the base plate member due to the air pressure in the airtightness test.

[Comparative Example 2]
The test was performed under the same conditions as in Example 1 except that the brazing material was tin solder of Ag: 3% by mass, Cu: 0.7% by mass, and the remaining Sn having a melting point of about 220 ° C. As a result, a part of the comb-shaped heat radiation pin member dropped off due to the temperature rise when the insulating substrates on which the power semiconductor chips were mounted were joined by soldering, and could not be used for the heat dissipation test.

Example 8
The two types of comb-shaped heat radiating pin members used were tested under the same conditions as in Example 1 except that the number of pins was both increased. In this case, one of the comb-shaped heat radiation pin members has n pins: 17 pins, an average pin length Lp _M : 10.0 mm, an average projection pin diameter Dp _M : 3.0 mm, and an average projection pin gap Ap _M : 1 0.0 mm, pin gap ratio Rp: 0.24. The other comb-shaped radiating pin member has 16 pins, average pin length Lp _M : 10.0 mm, average projection pin diameter Dp _M : 3.0 mm, average projection pin gap Ap _M : 1.0 mm, The pin gap ratio Rp is 0.23. The base plate member is brazed with 10 comb-shaped radiating pin members with n pins: 17 and 9 comb-shaped heat radiating pin members with n pins: 16 pins. The pin member was just large enough to fit. As a result of the test, heat dissipation: Δ evaluation, air tightness: ○ evaluation.
As the flow resistance of the refrigerant (water) increased, the refrigerant flow rate decreased at the same water supply pressure as in Example 1, and as a result, the heat dissipation decreased. It is considered that it is possible to obtain heat dissipation equal to or higher than that of Example 1 by increasing the water supply pressure and increasing the refrigerant flow rate.

Example 9
The two types of comb-shaped heat radiation pin members used were tested under the same conditions as in Example 1 except that the number of pins was reduced. In this case, one of the comb-shaped heat dissipation pin members has n pins: 17 pins, an average pin length Lp _M : 10.0 mm, an average projection pin diameter Dp _M : 1.0 mm, and an average projection pin gap Ap _M : 3 0.0 mm, pin gap ratio Rp: 0.74. The other comb-shaped radiating pin member has 16 pins, average pin length Lp _M : 10.0 mm, average projection pin diameter Dp _M : 1.0 mm, average projection pin gap Ap _M : 3.0 mm, The pin gap ratio Rp is 0.73. The base plate member is brazed with 10 comb-shaped radiating pin members with n pins: 17 and 9 comb-shaped heat radiating pin members with n pins: 16 pins. The pin member was just large enough to fit. As a result of the test, heat dissipation: Δ evaluation, air tightness: ○ evaluation.
In contrast to Example 1, the pin density was low and the pin spacing was wide, resulting in low heat dissipation.

Example 10
Same as Example 1 except that the pin arrangement (pin arrangement similar to FIG. 5) with a higher pin density at the central part in the direction perpendicular to the average flow direction of the refrigerant (hereinafter referred to as “the central part in the width direction”) is adopted. The test was conducted under the following conditions. Of the two types of comb-shaped heat radiation pin members used, one has n pins: 21 pins, average pin length Lp _M : 10.0 mm, average projection pin diameter Dp _M : 2.0 mm, average projection pin gap Ap _M : 1.1 mm, pin gap ratio Rp: 0.39, minimum projection pin gap Ap _MIN : 1.0 mm, maximum projection pin gap Ap _MAX : 2.0 mm. On the other hand, the number of pins n is 20, the average pin length Lp _{M is} 10.0 mm, the average projected pin diameter Dp _{M is} 2.0 mm, the average projected pin gap Ap _{M is} 1.05 mm, and the pin gap ratio Rp is 0.00. 38, the minimum projection pin gap Ap _MIN : 1.0 mm, and the maximum projection pin gap Ap _MAX : 2.0 mm. The base plate member is brazed with 10 comb-shaped radiating pin members with n: 21 pins and 9 comb-shaped radiating pin members with n: 20 pins. The counterbore of the base plate member is radiated with comb teeth. The pin member was just large enough to fit. As a result of the test, the heat dissipation was evaluated as ◎, and the airtightness was evaluated as ○.
By increasing the pin density only at the site just behind the mounting position of the semiconductor chip, efficient heat dissipation was achieved while suppressing an increase in the flow resistance of the refrigerant.

[Comparative Example 3]
Individual pins were attached to the base plate member by caulking. The pin was produced by processing a C1020 wire. A hole for inserting a pin was provided in a base plate member made of C1020, 1 / 2H material, and the pin member was inserted into the hole and fixed by a caulking jig. The cross-sectional shape of the pins, the pin length, the pin diameter, the size of the base plate member, and the region where the pins on the surface of the base plate member are arranged are the same as in the first embodiment. However, the distance between the pins was made larger than that in Example 1 because of the need for caulking. The total number of pins in the heat sink with pins was 77% with respect to Example 1. Except for these, the test was performed under the same conditions as in Example 1. As a result, heat dissipation: x evaluation, air tightness: o evaluation.
Possible causes of inferior heat dissipation are that the total number of pins was small and that some heat transfer loss occurred in the caulking portion. In addition, compared with Example 1, preparation of the heat sink with a pin required much effort and time. In addition, fluctuations were observed in the height and mounting angle of the pins, and the dimensional accuracy as a heat sink with pins was inferior.

DESCRIPTION OF SYMBOLS 1 Pin 2 Base part 3 End surface brazed and joined with a baseplate member 4 Pin longitudinal direction 5 Base longitudinal direction 6 Punching direction 7 Concave part 8 Convex part 9 Thickness direction of the baseplate member to join 10 Comb-shaped heat radiation pin member 11 Brazing material layer 20 Base plate member 30 Pinned heat sink 31 Cooling jacket 32 Refrigerant inlet 33 Refrigerant outlet 34 Average flow direction of refrigerant 41 Semiconductor chip 42 Aluminum nitride insulating substrate 43 Solder layer 44 Cover 45 Heat dissipating copper plate 46 Circuit copper plate 47 Active metal containing Ag-Cu Brazing material layer 51 Thermocouple

Claims (8)

  A press-molded product obtained by punching a copper or copper alloy plate-like material, and a plurality of pins arranged in a comb-like shape and a base portion supporting these pins at the root portion form an integrated structure without a joint portion. And the comb-shaped heat radiation pin member for a heat sink with a pin which has the end surface brazed to the base plate member of a heat sink on the pin back surface side of the said base. The comb-shaped heat radiation pin member according to claim 1, wherein an average pin length Lp _M defined by (A) below is 3.0 to 30.0 mm, and an average projected pin diameter Dp _M is 0.8 to 5.0 mm. .
(A) On the projection plane viewed in the punching direction, a reference line that is perpendicular to the thickness direction of the base plate members to be joined is set at an arbitrary position on the back surface side of the pin from the end face of the base, and from the reference line When the distance is called “height”, the number of pins is n, and the minimum height of the base between two adjacent pins is called “inter-pin height” between the pins, The difference between the height Hp of the pin Hp and the height between the adjacent pins (the higher pin height if the height between the pins on both sides is different) Hb is expressed as the value of the pin length Lp And the distance between two intersections of the line representing the 1/2 pin height (Hp−Hb) / 2 and the pin outline is defined as the “projection pin diameter Dp” of the pin, and the Dp of the n pins Is defined as “average projection pin diameter Dp _M ”. Comb teeth radiation fins according to claim 2 mean aspect ratio Lp _M / Dp _M pins is expressed by the ratio of the average projected pin diameter Dp _M and the average pin length Lp _M is 0.6 to 37.5 Element. 4. The comb-shaped heat radiation pin member according to claim 2, wherein an average projected pin gap Ap _M defined by (B) below is 1.0 to 5.0 mm.
(B) For two adjacent pins, the distance between the intersections of the line representing the central height of the common height region between the two pins and the contour line facing both pins is the “projection pin gap Ap” between the pins. And the average value of Ap at n−1 locations is defined as “average projection pin gap Ap _M ”. Here, n is the number of pins. The comb-shaped heat radiation pin member according to any one of claims 2 to 4, wherein a pin gap ratio Rp defined by (C) below is 0.14 to 0.75.
(C) The “pin gap ratio Rp” is determined by the following equation (1) using the number n of pins, the average projected pin gap Ap _M , and the average projected pin diameter Dp _M.
Rp = (n−1) Ap _M / [n · Dp _M + (n−1) Ap _M ] (1)   A plurality of comb-shaped radiating pin members according to any one of claims 1 to 5 are juxtaposed and joined to the back surface of the heating element mounting surface of a base plate member made of copper or a copper alloy for mounting the heating element on the surface. And a heat sink with a pin having a joint structure in which the end surface and the surface of the base plate member are in close contact with each other by brazing using a brazing material having a melting point of 300 to 600 ° C.   The heat sink with a pin according to claim 6, wherein the joining structure is formed by brazing using a brazing material made of Zn or a Zn—Al-based alloy having an Al content of 0 to 10 mass%. A step of punching a copper or copper alloy plate-like material to obtain an intermediate product having a plurality of pins arranged in a comb-like shape and a base part supporting these pins at the root part,
A step of changing the cross-sectional shape of the pin by subjecting the intermediate product to one or more presses;
The manufacturing method of the comb-tooth-shaped radiation | emission pin member of any one of Claims 1-5 which have these.