JP2015233036A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which can reduce electrical resistance among a plurality of chips.SOLUTION: A semiconductor device comprises a frame 1, first and second semiconductor chips 2, 3 and a conductive member 4. The frame 1 is bent in a manner such that the first semiconductor chip 2 and the second semiconductor chip 3 are arranged opposite to each other across the conductive member 4. The conductive member 4 is electrically connected to both of the first and second semiconductor chips 2, 3 by coming into contact with both of the first and second semiconductor chips 2, 3.

Description

  The present invention relates to a semiconductor device, and more particularly to a semiconductor device having a power semiconductor element.

  Since a semiconductor device such as a power module outputs a larger electric power than a normal semiconductor device, there is a high possibility of causing a malfunction due to heat generated during driving. Therefore, various countermeasures are taken as shown below. For example, Japanese Patent Laying-Open No. 2005-142189 (Patent Document 1) discloses a semiconductor device in which a metal conductor and a semiconductor element are arranged so that a wiring length of a current path between the metal conductor and the semiconductor element is shortened. Has been. By shortening the wiring length, temperature rise when a drain current or the like flows through the wiring can be suppressed.

  In addition, for example, in Japanese Patent Application Laid-Open No. 2012-191167 (Patent Document 2), a power semiconductor element is formed by bending a heat radiating plate for cooling heat generated from the power semiconductor element from the viewpoint of improving heat dissipation of the power module. It is arranged so that it surrounds.

  Further, for example, in Japanese Patent Application Laid-Open No. 2004-22601 (Patent Document 3), a first circuit on which a first semiconductor chip is placed and a second circuit on which a second semiconductor chip is placed are overlapped. Thus, the semiconductor device can be reduced in size.

JP 2005-142189 A JP 2012-191167 A JP 2004-22601 A

  The semiconductor device of Patent Document 1 is formed such that the distance between the metal conductor and the semiconductor element is shortened by adjusting the layout. For this reason, if the configuration of the semiconductor device is complicated, it is difficult to adjust such a layout, and it may be difficult to shorten the interval between the metal conductor and the semiconductor element.

  Although the semiconductor device of Patent Document 2 can improve the heat dissipation effect, it has not been devised to reduce the heat itself generated by the power semiconductor element, so that the heat dissipation effect may be weakened if the heat generation amount increases in the future. There is.

  In the semiconductor device of Patent Document 3, the outer size is reduced by the bent lead frame and the wiring inductance is reduced, but the two semiconductor chips mounted on the lead frame are not electrically connected to each other. Since no consideration is given to shortening the wiring between the plurality of semiconductor chips or reducing the resistance, there is a possibility that the resistance increases between these semiconductor chips and the amount of heat generation increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a semiconductor device capable of reducing electrical resistance between a plurality of chips.

  The semiconductor device of the present invention includes a frame, first and second semiconductor chips, and a conductive member. The frame is bent so that the first semiconductor chip and the second semiconductor chip are disposed so as to face each other and sandwich the conductive member. The conductive member is electrically connected to both the first and second semiconductor chips by contacting both the first and second semiconductor chips.

  According to the present invention, the first semiconductor chip and the second semiconductor chip are electrically connected at a short distance by the conductive member sandwiched between the first and second semiconductor chips facing each other. . For this reason, the value of electrical resistance and the amount of heat generated between the first semiconductor chip and the second semiconductor chip can be reduced.

1 is a schematic perspective view of a semiconductor device in a first embodiment. It is a schematic perspective view which shows the aspect with the semiconductor chip arrange | positioned on the main surface of a flame | frame before bending the flame | frame of FIG. It is a schematic perspective view which shows the aspect by which the spring structure of FIG. 1 was connected to the external conduction member. It is a schematic sectional drawing which shows the aspect connected with the spring structure of the 1st example of Embodiment 1, and a semiconductor chip along the AA line of FIG. It is a schematic sectional drawing which shows the aspect to which the spring structure of the 1st example of Embodiment 1 and a semiconductor chip are connected along the BB line of FIG. It is a schematic sectional drawing which shows the aspect with which the spring structure of the 2nd example of Embodiment 1 and a semiconductor chip are connected along the AA line of FIG. It is a schematic sectional drawing which shows the aspect with which the spring structure of the 2nd example of Embodiment 1 and a semiconductor chip are connected along the BB line of FIG. FIG. 6 is a schematic perspective view of a semiconductor device in a second embodiment. It is a schematic perspective view which shows the aspect by which the electroconductive flat plate of FIG. 8 was connected to the external conduction member. It is a schematic perspective view which shows the aspect with the semiconductor chip arrange | positioned on the flame | frame and its main surface before bending the flame | frame of FIG. It is a schematic sectional drawing which shows the aspect connected with the spring structure of the 1st example of Embodiment 2, and a semiconductor chip along CC line of FIG. It is a schematic sectional drawing which shows the aspect connected with the spring structure of the 1st example of Embodiment 2, and a semiconductor chip along the DD line of FIG. It is a schematic sectional drawing which shows the aspect connected with the spring structure of the 2nd example of Embodiment 2, and a semiconductor chip along the CC line of FIG. FIG. 9 is a schematic cross-sectional view showing an aspect in which the spring structure of the second example of the second embodiment and the semiconductor chip are connected along line DD in FIG. 8. FIG. 6 is a schematic perspective view of a semiconductor device in a third embodiment. FIG. 16 is a schematic perspective view showing an aspect of the frame and a semiconductor chip disposed on the main surface of the frame before bending the frame of FIG. 15. FIG. 10 is a schematic perspective view of a semiconductor device in a fourth embodiment. FIG. 18 is a schematic development view showing an aspect of the frame and a semiconductor chip disposed on the main surface of the frame before bending the frame of FIG. 17. It is a schematic sectional drawing which shows the aspect to which the spring structure of Embodiment 4 and a semiconductor chip are connected along the XIX-XIX line | wire of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
Referring to FIG. 1, a power module 10 according to the present embodiment is a semiconductor device including a power semiconductor element. The power module 10 mainly includes a frame 1, a power semiconductor chip 2 (first semiconductor chip), a driving element chip 3 (second semiconductor chip), and a spring structure 4 (conductive member). ing.

  Referring to FIG. 2, frame 1 is formed of, for example, copper that can be bent, and is a flat plate-like member that has, for example, a rectangular planar shape and has a certain thickness before bending. is there. The flat shape of the frame 1 is significantly larger in one direction (left-right direction in FIG. 2) than in the other direction (depth direction in FIG. 2) intersecting the one direction (for example, left and right in FIG. 2). 2 to 4 times as long as the depth direction in FIG. 2).

  The power semiconductor chip 2 has a power semiconductor element such as an IGBT (Insulated Gate Bipolar Transistor). The drive element chip 3 has a drive element such as a smoothing capacitor. The power semiconductor chip 2 and the driving element chip 3 are arranged on one main surface of the frame 1 at a distance from each other. Specifically, the power semiconductor chip 2 and the drive element chip 3 are arranged with a space therebetween in the longitudinal direction of the flat plate formed by the frame 1 (left and right direction in FIG. 2).

  On the surface of the power semiconductor chip 2, for example, three terminals 2a, 2b, 2c for connecting to the outside are formed at intervals, and on the surface of the driving element chip 3, for example, connecting to the outside. Three terminals 3a, 3b, 3c are formed at intervals. These terminals correspond to, for example, electrode pads for electrical connection with semiconductor elements formed on the power semiconductor chip 2 and the drive element chip 3. Here, for convenience of explanation, a configuration in which three terminals are formed on each of the power semiconductor chip 2 and the drive element chip 3 is shown, but the number of the terminals is arbitrary.

  In FIG. 2, the power semiconductor chip 2 is arranged at the center in the horizontal direction in the figure, and the drive element chip 3 is arranged at one end (left side) in the horizontal direction in the figure. The arrangement of 2 and the drive element chip 3 may be reversed.

  With reference to FIG. 3, the spring structure 4 is attached to the external conducting member 5. The external conducting member 5 is a flat plate member made of copper, for example, but is not limited thereto. In FIG. 3, three spring structures 4 (spring structures 4a, 4b, 4c) are attached on one main surface (for example, relatively below) of a flat plate constituting the external conducting member 5. The number of spring structures 4 that can be attached to the conducting member 5 is arbitrary. The spring structure 4 (4a, 4b, 4c) is made of, for example, copper, and an elongated plate-like member having a length in the width direction intersecting the extending direction is w with respect to the extending direction. It is configured to have a plurality of portions (that is, portions that are curved in a wave shape) that are alternately curved at opposite intervals in the opposite direction (the upper portion and the lower portion in FIG. 3 alternate). Due to the wavyly curved portion, the spring structure 4 has a structure in which the plate-like member can expand and contract like a spring in the extending direction.

  The external conducting member 5 is a plate-like member made of, for example, copper and having a rectangular planar shape. The external conducting member 5 and the spring structure 4 are connected to each other by, for example, solder. In FIG. 3, a plurality of spring structures 4 a, 4 b, 4 c are connected to the external conducting member 5 at intervals with respect to the width direction intersecting the direction in which the spring structure 4 extends.

  Referring to FIGS. 1 and 2 again, the frame 1 is bent at the bent portions 1a, 1b, and 1c so that the extending directions in the longitudinal direction of the flat plate are changed by about 90 °. This bending is performed by using a generally known method such as bending using a mold.

  Thereby, for example, the power semiconductor chip 2 disposed in the region between the bent portion 1b and the bent portion 1c and the drive element chip 3 disposed in the region on the left side of the bent portion 1a are opposed to each other. It becomes arrangement to do. At this time, the main surface of the region between the bent portion 1b and the bent portion 1c and the main surface of the region on the left side of the drawing with respect to the bent portion 1a are arranged so as to be substantially parallel to each other. The surface of the chip 2 and the surface of the driving element chip 3 face each other so as to be substantially parallel.

  In FIG. 1, a driving element chip 3 is arranged on the upper side (particularly right above) with a gap from the power semiconductor chip 2. The power semiconductor chip 2 and the driving element chip 3 may be completely overlapped in plan view, but may be configured to overlap each other at least partially in plan view.

  The power semiconductor chip 2 and the drive element chip 3 facing each other are arranged so as to sandwich the spring structure 4. That is, referring to FIG. 4, a spring structure 4 as a conductive member is provided between the power semiconductor chip 2 and the drive element chip 3 facing each other in the vertical direction of the figure. It arrange | positions so that it may electrically connect with both of the chip | tips 3.

  Here, in particular, as shown in FIGS. 4 and 5, for example, a terminal 2b formed on the power semiconductor chip 2 and a terminal 3b formed on the drive element chip 3 are interposed between them in the vertical direction of FIG. It becomes the aspect connected by the spring structure 4b pinched | interposed. Similarly, the terminal 2a and the terminal 3a are connected by the spring structure 4a, and the terminal 2c and the terminal 3c are connected by the spring structure 4c, respectively. The spring structures 4a, 4b, and 4c are arranged so as to at least partially overlap each of the chips 2 and 3 in a plan view, but may be arranged so as to overlap the entire surfaces of both the chips 2 and 3 in a plan view. Good.

  In the first example of the present embodiment, the power semiconductor chip 2 and the driving element chip 3 and the spring structure 4 are connected to each other by so-called pressure contact. That is, for example, in the cross-sectional view of FIG. 4, both the power semiconductor chip 2 (terminal 2b) and the drive element chip 3 (terminal 3b) are connected so as to contact each other with the spring structure 4 (4b) interposed therebetween. Yes. Here, both the power semiconductor chip 2 (the terminal 2b) and the drive element chip 3 (the terminal 3b) are connected to the spring structure 4 in a state where stress is applied to the spring structure 4 side. This stress may be a stress caused by heat, or may be a stress caused by applying only pressure without applying heat.

  A through hole 1d may be formed in the frame 1 so as to penetrate from one main surface to the other main surface. A similar through hole 5 a may be formed in the external conducting member 5. For example, external wiring (not shown) for inputting an electric signal from the outside to the frame 1, the power semiconductor chip 2 mounted on the frame 1, and the driving element chip 3 is connected to the through hole 1 d of the frame 1. Similarly, an external wiring (not shown) for outputting an electrical signal output from, for example, the power semiconductor chip 2 and the drive element chip 3 is connected to the through hole 5a of the external conducting member 5. In contrast to the above, external wiring on the output side may be connected to the through hole 1d, and external wiring on the input side may be connected to the through hole 5a.

  The external conducting member 5 may be directly connected to the outside by an electric wire or the like for connecting to the outside of the power module 10, or may be electrically connected to a semiconductor chip or the like different from the frame 1.

  A bent portion 1c is provided in the frame 1, and the main surface of at least a part of the frame 1 in FIG. 2 (that is, the region on the right side of the bent portion 1c) is along the same direction as the main surface of the external conducting member 5 (vertical direction Preferably). In this way, when a current flows during driving of the power module 10, the magnetic field is canceled between the external conducting member 5 and the frame 1, and the inductance can be reduced.

Next, the manufacturing method of the power module 10 of this Embodiment is demonstrated.
First, as shown in FIG. 2, the power semiconductor chip 2 and the driving element chip 3 are arranged and fixed on the frame 1 having the bent portions 1a, 1b, and 1c (portions to be bent). Next, for example, the spring structure 4 is in contact with at least part of the power semiconductor chip 2 (on the terminals 2a to 2c of the power semiconductor chip 2) disposed in the region between the bent portion 1b and the bent portion 1c. Placed. Thereby, the external conducting member 5 is placed on one main surface of the frame 1.

  Next, the frame 1 is bent using, for example, a mold. Thereby, for example, the drive element chip 3 (terminals 3 a to 3 c of the drive element chip 3) is placed in contact with at least a part of the spring structure 4.

  Next, in this state, for example, a step (pressure contact) is performed in which heat or pressure from above the frame 1 is applied. Thereby, the power semiconductor chip 2 (terminals 2a to 2c) and the driving element chip 3 (terminals 3a to 3c) are joined to the spring structure 4 in a state where stress is applied to the spring structure 4 side.

Next, the effect of this Embodiment is demonstrated.
First, as shown in FIG. 2, the power semiconductor chip 2 and the driving element chip 3 are arranged on one main surface of the frame 1 at an interval in the longitudinal direction of the frame 1 in plan view, and the frame 1 is bent. Consider the case where the power semiconductor chip 2 and the driving element chip 3 are electrically connected. In this case, the terminal of the power semiconductor chip 2 and the terminal of the driving element chip 3 are connected by a wire or a copper lead frame. At this time, if the distance between the power semiconductor chip 2 and the driving element chip 3 is large, the wiring such as the wire becomes long, and the electric resistance and the inductance due to the wiring become large. If the value of the electrical resistance of the wiring increases, the amount of heat generated by the wiring increases.

  Therefore, in the present embodiment, as shown in FIG. 1, the power semiconductor chip 2 and the driving element chip 3 are arranged so as to face each other, and the conductive spring structure is in contact with the terminals of both chips. The body 4 is sandwiched. Thus, the shortest distance (in the direction along the spring structure 4b) on the wiring (spring structure 4b) connecting, for example, the terminal 2b of the power semiconductor chip 2 and the terminal 3b of the drive element chip 3, for example, is as shown in FIG. 4 is the distance between the point P1 and the point P2. Here, the point P1 is one of the intersections of the terminal 3b and the spring structure 4b, and the point P2 is one of the intersections of the terminal 2b and the spring structure 4b.

  As described above, according to the present embodiment, the distance between the power semiconductor chip 2 and the drive element chip 3 can be reduced, so that the length of the spring structure 4b connecting the terminal 2b and the terminal 3b is set to the frame 1 Is shorter than the wiring connecting the terminal 2b and the terminal 3b when not bent. For this reason, the value of the electrical resistance and inductance of the wiring between the terminal 2b and the terminal 3b can be reduced. Specifically, if the frame 1 is bent as in the present embodiment without changing the distance between the power semiconductor chip 2 and the drive element chip 3 in the direction along the main surface of the frame 1, the frame Compared to the case where 1 is not bent, the shortest distance of the conductive member connecting the terminal 2b and the terminal 3b can be ½ or less.

  Further, since the conductive member sandwiched between the power semiconductor chip 2 and the driving element chip 3 has a spring structure that can expand and contract in the extending direction, the spring structure 4 is driven by the power semiconductor chip 2 and the driving element chip 3. When the element chip 3 is connected by, for example, pressure contact, the stress applied by the chips 2 and 3 to the spring structure 4 can be relaxed.

  Therefore, when the power semiconductor chip 2 and the driving element chip 3 are pressed against each other by heat, expansion and contraction of the terminals 2 b and the like due to thermal stress are alleviated by expansion and contraction of the spring structure 4. Similarly, when the power semiconductor chip 2 and the driving element chip 3 are pressed against each other by pressure, the expansion and contraction of the terminals 2b and the like due to the stress applied by the chips 2 and 3 to the spring structure 4 is similar to the expansion and contraction of the spring structure 4. Is alleviated by Since the stress applied to each chip 2 and 3 is relaxed, the life of each chip 2 and 3 can be extended.

  In this embodiment, since the chips 2 and 3 and the spring structure 4 are connected by pressure contact, for example, without applying heat or using a bonding material such as solder, the chips 2 and 3 3 and the spring structure 4 can be connected. For this reason, it is possible to extend the life of each of the chips 2 and 3 by eliminating the occurrence of damage due to thermal fatigue or thermal deterioration at the connection portion between the chips 2 and 3 and the spring structure 4. Furthermore, the manufacturing cost of the power module 10 can be reduced by not using solder for the connection between the chips 2 and 3 and the spring structure 4.

  However, referring to FIGS. 6 and 7, as a modification (second example) of the present embodiment, chips 2 and 3 and spring structure 4 may be connected by solder 6 instead of press contact. The solder 6 is sandwiched between the terminals 2b and 3b and the spring structure 4b, and is disposed so as to contact at least a part of the terminals 2b and 3b and the spring structure 4b. The solder 6 may be arranged so as to cover the entire surface (including side surfaces) of the terminals 2b and 3b and fill the terminals 2b and 3b. The terminals 2b and 3b and the spring structure 4b are electrically connected by the solder 6. As shown in FIG. 7, the solder 6 preferably has the same length w in the width direction as the spring structure 4, but may not have such an aspect. The terminals 2a and 3a and the spring structure 4a, and the terminals 2c and 3c and the spring structure 4c may be similarly connected by the solder 6.

  The configuration of the second example of FIGS. 6 and 7 is substantially the same as the configuration of the first example of FIGS. 4 and 5 except that the solder 6 is disposed. The description will not be repeated.

  If the solder 6 is used, the area where the terminals 2b and 3b and the spring structure 4b are joined increases. Thereby, the conductivity between the terminals 2b and 3b and the spring structure 4b is improved, and the electrical resistance and the amount of heat generated between them can be reduced.

  The method of manufacturing the power module 10 when using the solder 6 is basically the same as the method of manufacturing the power module 10 by pressure welding, but after the frame 1 is bent, the power semiconductor chip 2 (terminals 2a to 2c) and the spring Solder 6 is sandwiched between the structure 4 and between the driving element chip 3 (terminals 3 a to 3 c) and the spring structure 4. In this state, the formed product is put into a furnace, and the solder 6 is melted by heating, whereby the power semiconductor chip 2 (terminals 2a to 2c) and the driving element chip 3 (terminals 3a to 3c) are electrically connected to the spring structure 4. Are joined together.

(Embodiment 2)
Referring to FIG. 8, in power module 20 of the present embodiment, one conductive flat plate 7 having a flat plate shape is attached to external conductive member 5 as a conductive member instead of spring structure 4. . The conductive flat plate 7 is a rectangular flat plate made of a conductive material having high slidability such as copper in a plan view.

  Referring to FIG. 9, conductive flat plate 7 has a main surface of external conductive member 5 and a main surface of conductive flat plate 7 on one main surface (for example, relatively below) of the flat plate constituting external conductive member 5. The surface is fixed so as to intersect (orthogonal) each other. The external conducting member 5 is connected to the conductive flat plate 7 by, for example, solder.

  Referring to FIG. 10, also in the present embodiment, frame 1 has bent portions 1 a, 1 b, and 1 c, similar to frame 1 of FIG. 2 of the first embodiment, on one main surface thereof. The power semiconductor chip 2 and the drive element chip 3 are arranged to face each other by being bent at the bent portion.

  In FIG. 8, the power semiconductor chip 2 and the driving element chip 3 facing each other are arranged so as to sandwich the conductive flat plate 7. That is, referring to FIG. 11, a conductive flat plate 7 as a conductive member is provided between power semiconductor chip 2 and drive element chip 3 facing each other in the vertical direction of the figure, and power semiconductor chip 2 and drive element chip are used. It arrange | positions so that it may electrically connect with both of the chip | tips 3.

  In the first example of the present embodiment, as shown in FIGS. 11 and 12, for example, a terminal 2d formed on the power semiconductor chip 2 and a terminal 3d formed on the drive element chip 3 are shown in FIG. It becomes the aspect connected by the electroconductive flat plate 7 pinched | interposed between these regarding the up-down direction. The terminals 2d and 3d and the conductive flat plate 7 are connected by pressure welding as in the first example of the first embodiment.

  Here, since the single conductive flat plate 7 is arranged, only the single terminals 2d and 3d are formed on each of the chips 2 and 3, and this is connected to the conductive flat plate 7. When a plurality of flat plates 7 are arranged, a plurality of terminals, that is, the number of terminals equal to the number of conductive flat plates 7 may be formed on each of the chips 2 and 3.

  The conductive flat plate 7 is disposed so as to overlap in at least a part of the power semiconductor chip 2 and the driving element chip 3 in plan view, but the entire surface and the plane of both the power semiconductor chip 2 and the driving element chip 3 are flat. You may arrange | position so that it may overlap in view.

  12, length w in the width direction of conductive flat plate 7 is preferably longer than, for example, length w in the width direction of spring structure 4 of the first embodiment. The length w in the width direction of the conductive flat plate 7 may be substantially the same as the length in the width direction intersecting the extending direction of the frame 1.

  Since the configuration of the second embodiment is substantially the same as the configuration of the first embodiment except that the conductive flat plate 7 is arranged as described above, the same elements are denoted by the same reference numerals, and the description thereof is omitted. Does not repeat.

Next, the effect of this Embodiment is demonstrated.
When the conductive flat plate 7 is used instead of the spring structure 4 as the conductive member as in the power module 20 of the present embodiment, the conductive flat plate 7 is for the power semiconductor chip 2 and the drive element facing each other. The chip 3 is connected (particularly, the terminal 2d and the terminal 3d). As a result, the shortest distance (within the conductive flat plate 7) between, for example, the terminal 2d of the power semiconductor chip 2 and the terminal 3d of the driving element chip 3, for example, is the distance between the point P3 and the point P4 in FIG. In particular, if the terminal 2d and the terminal 3d are at least partially overlapped in plan view, the shortest distance between the points P3 and P4 is equal to the thickness of the conductive flat plate 7 (in the vertical direction in FIGS. 11 and 12).

  Therefore, also in the present embodiment, as in the first embodiment, the terminal 1d and the terminal 2 are connected to each other by bending the frame 1 so that the power semiconductor chip 2 and the driving element chip 3 face each other, and the distance between the two is reduced. The distance to 3d is shorter than the wiring connecting the terminal 2b and the terminal 3b when the frame 1 is not bent. For this reason, the value of the electrical resistance and inductance between the terminal 2d and the terminal 3d can be reduced.

  Note that the conductive flat plate 7 of the present embodiment usually has a longer length w in the width direction than the spring structure 4, so that the cross-sectional area that intersects the direction in which the current flows increases. For this reason, the conductive plate 7 has a smaller electrical resistance value than the spring structure 4, and the amount of heat generated when a current flows is reduced. Further, the conductive flat plate 7 does not have a wave-shaped curved portion like the spring structure 4. Also from this point of view, the conductive flat plate 7 has a smaller electrical resistance value than the spring structure 4, and the amount of heat generated when a current flows is reduced.

  Further, by using a flat plate made of copper as the conductive flat plate 7, the value of the electric resistance of the conductive flat plate 7 can be further reduced as compared with the case of using another metal material.

  Referring to FIGS. 13 and 14, as a modification (second example) of the present embodiment, terminals 2 d and 3 d and conductive flat plate 7 are replaced by press-contact as in the second example of the first embodiment. May be connected by solder 6. Also in the present embodiment, the solder 6 may be disposed so as to cover the entire surface (including side surfaces) of the terminals 2b and 3b and fill the terminals 2b and 3b.

(Embodiment 3)
Referring to FIGS. 15 and 16, power module 30 of the present embodiment includes a plurality of (for example, two) power semiconductor chips 2 and drive element chips 3 on one main surface of frame 1, respectively. They are spaced apart from each other in plan view.

  Specifically, as shown in FIG. 16, two power semiconductor chips 2 are provided in the region between the bent portion 1b and the bent portion 1c, and two drive elements are provided in the region on the left side of the bent portion 1a. Each chip 3 is arranged. However, the arrangement of the power semiconductor chip 2 and the drive element chip 3 may be reversed.

  Referring to FIG. 15, in the present embodiment, two external conducting members 5 and spring structure 4 are arranged at a distance from each other in the depth direction of the figure. Specifically, the spring structure 4 on the near side in FIG. 15 is sandwiched between the chips 2 and 3 on the far side in the depth direction of FIG. 16 so as to be sandwiched between the chips 2 and 3 on the near side in the depth direction in FIG. 15 is arranged so that the spring structure 4 is connected to the chips 2 and 3 (terminals thereof). In FIG. 15, the spring structure 4 is fixed to the external conducting member 5, but the conductive flat plate 7 may be fixed instead of the spring structure 4. Further, the conductive member (spring structure 4 or conductive flat plate 7) and the chips 2 and 3 may be connected by pressure contact or may be connected by solder 6.

  As shown in the power module 30, in the application of the present embodiment, the number of power semiconductor chips 2 and drive element chips 3 is not questioned.

(Embodiment 4)
Referring to FIGS. 17 to 19, in the power module 40 of the present embodiment, the extending direction of the short direction is changed by about 90 ° with respect to the short direction in which the frame 1 intersects the long direction in plan view. The bent portion 1e is bent and the bent back preventing portion 1f is formed by the bent portion 1e. In this respect, the power module 40 is different from the power module 10 of the first embodiment.

  For example, the bending back preventing portion 1f extends from one end and the other end 1g in the depth direction of FIG. 17 in the region where the driving element chip 3 on the left side of the bent portion 1a of FIG. 18 is disposed. However, the present invention is not limited to this, and the bending back prevention portion 1f may extend from one end and the other end in the depth direction of FIG. 17 in the region between the bent portion 1b and the bent portion 1c of FIG.

  The bending back preventing portion 1f extending from the pair of end portions 1g in the region where the driving element chip 3 on the left side of the bent portion 1a in FIG. 18 is disposed is 1 in the region between the bent portion 1b and the bent portion 1c. It extends to the end 1g of the pair. As shown in FIG. 19, the bending back prevention portion 1f is fixed so as to contact a pair of end portions 1g in a region between the bent portion 1b and the bent portion 1c, for example. This fixing may be performed by, for example, solder, or the bending back prevention portion 1f may be fitted into a shallow concave portion formed in the end portion 1g of the frame 1. Alternatively, the anti-bending portion 1f that reaches the end 1g of the frame 1 may be further bent there and fixed by having a form that wraps around the bottom not shown in FIG. Further, for example, a hole (not shown) is provided on the surface of the bending back prevention portion 1f, a protrusion (not shown) is provided on the surface of the end 1g, and the bending back prevention portion 1f is kept bent by fitting the protrusion into the hole. May be fixed.

  17 and 18 has a rectangular shape in plan view, but is not limited to this, and may have any shape such as a trapezoidal shape.

  In FIG. 17, the spring structure 4 is used as a conductive member. In FIG. 19, the spring structures 4a, 4b, 4c and the chips 2, 3 are connected by pressure contact. However, also in the present embodiment, the conductive plate 7 may be used as the conductive member as in the other embodiments, or the conductive member and the chips 2 and 3 may be connected by solder.

  The configuration of the fourth embodiment is substantially the same as the configuration of the first embodiment except that the bending back prevention portion 1f is arranged as described above, and therefore the same elements are denoted by the same reference numerals, The explanation will not be repeated.

Next, the effect of this Embodiment is demonstrated.
If the bending back preventing portion 1f is not disposed on the frame 1 as in the first embodiment, even when the frame 1 is bent as shown in FIG. 1 at the bent portions 1a and 1b, the power module 10 is not driven. Due to thermal stress due to heat generation, the bent portions 1a and 1b may not be kept bent and may be unfolded again. That is, for example, the left region (where the drive element chip 3 is formed) in FIG. 18 of the frame 1 tends to float upward in FIG. In this case, there is a possibility that the spring structure 4 that connects the power semiconductor chip 2 and the driving element chip 3 receives a large stress and is broken, for example.

  Therefore, in the power module 40 according to the present embodiment, the frame 1 is provided with a bending back prevention portion 1f, which is fixed to a portion facing the portion where the bending back prevention portion 1f is formed when the frame 1 is bent. As a result, even if thermal stress is applied to the frame 1 to return to the state in which the bent portions 1a and 1b are not bent during driving, the region where the power semiconductor chip 2 of the frame 1 is formed and the driving element chip 3 are formed. It is possible to maintain a state in which the region is opposed to each other, and it is possible to maintain a state in which the frame 1 is bent at the bent portions 1a and 1b.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1 frame, 1a, 1b, 1c, 1e bent part, 1d, 5a through hole, 1f bending return preventing part, 1g end part, 2 power semiconductor chip, 2a, 2b, 2c, 2d, 3a, 3b, 3c, 3d terminal 3 Drive element chip, 4, 4a, 4b, 4c Spring structure, 5 External conducting member, 6 Solder, 7 Conductive flat plate 10, 20, 30, 40 Power module.

Claims (6)

A flat frame made of a bendable material;
First and second semiconductor chips spaced apart from each other on one main surface of the frame;
A conductive member,
The frame is bent so that the first semiconductor chip and the second semiconductor chip are arranged to face each other and sandwich the conductive member;
The semiconductor device, wherein the conductive member is electrically connected to both the first and second semiconductor chips by contacting both the first and second semiconductor chips.   The semiconductor device according to claim 1, wherein the conductive member has a spring structure.   The semiconductor device according to claim 1, wherein the conductive member has a flat plate shape.   4. The semiconductor device according to claim 1, wherein the first and second semiconductor chips are joined to the conductive member in a state where stress is applied to the conductive member side. 5.   The semiconductor device according to claim 1, wherein the first and second semiconductor chips and the conductive member are joined to each other by solder.   6. The semiconductor device according to claim 1, wherein the frame includes a bend return prevention unit for maintaining a bent state. 7.

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