Double-sided cooling type power module and manufacturing process therefor

Abstract

Double-sided cooling-type power module in which a pair of semiconductor chips (310, 320) are arranged between an upper substrate (100) and a lower substrate (200), the double-sided cooling-type power module comprising: Output connection leads (610) are configured to be arranged on a lower surface of the upper substrate (100) and each connected to the pair of semiconductor chips (310, 320); a positive terminal lead (620) configured to be located on one side of an upper surface of the lower substrate (200) for connection to any semiconductor chip selected from the pair of semiconductor chips (310, 320); and a negative terminal lead (630) configured to be located on the upper side of the upper surface of the lower substrate (200) to be connected to the other semiconductor chip of the pair of semiconductor chips (310, 320), wherein a brazing bond is made between the upper substrate (100) and the output connection lead (610), the lower substrate (200) and the positive connection lead (620), or the lower substrate (200) and the negative connection lead (630), and a solder bond is made between the semiconductor chip and the output lead (610), between the semiconductor chip and the positive lead (620), and between the semiconductor chip and the negative lead (630), wherein the lower substrate (200) comprises a lower ceramic layer (220) made of a ceramic material, a positive terminal layer (230) arranged on one side of an upper surface of the lower ceramic layer (220) to be bonded to the positive terminal lead (620), and a negative terminal layer (240) arranged on the other side of the upper surface of the lower ceramic layer (220) to be bonded to the negative terminal lead (630), and wherein the positive terminal layer (230) and the negative terminal layer (240) are arranged to be isolated from each other.

Description

1. Field of the invention

[0001] The present disclosure relates to a double-sided cooling-type power module and a manufacturing process therefor, and in particular to a double-sided cooling-type power module with a simpler design and a smaller volume, and a manufacturing process therefor. 2. Description of the related facts

[0002] A power module has been used to supply high power (current / voltage) to control or operate a motor of a hybrid vehicle, an electric vehicle or the like.

[0003] In particular, a double-sided cooling-type power module, in which substrates are arranged over an upper and lower section of a semiconductor chip respectively, and heat sinks are located on the outer side faces of the substrates, can exhibit excellent cooling properties and can be manufactured more compactly compared to a general single-sided cooling-type power module. Therefore, there is an increasing trend toward the use of double-sided cooling-type power modules.

[0004] Document US 2013 / 0020694 A1 discloses a double-sided cooled power module package with a single-phase leg topology comprising two IGBT and two diode semiconductor chips.

[0005] Document DE 10 2015 219 852 A1 discloses a power module with two-sided cooling.

[0006] Publication US 2003 / 0090873 A1 discloses a coolant-cooled semiconductor device with good heat dissipation capability.

[0007] Document US 2014 / 0159216 A1 discloses a semiconductor module configured such that thermal radiation substrates are connected to conductor frames and semiconductor chips are directly connected to the conductor frames, so that the semiconductor chips are not connected to the conductor frames via conductive parts of the thermal radiation substrates. Summary of the invention

[0008] The present disclosure provides a double-sided cooling-type power module and a manufacturing method therefor.

[0009] As in Fig. As shown in Figure 1, a double-sided cooling-type power module can be manufactured by sequentially stacking a lower substrate 20, a semiconductor chip 30, and an upper substrate 10, whereby, since a positive terminal layer 23, negative terminal layers 14 and 25, and output terminal layers 13 and 24 are distributed on the upper substrate 10 and the lower substrate 20, a structure is complicated in which conductive lines 51 and 52 are used to electrically connect these and insulators 15, 26, and 27 are inserted into the substrates, etc.

[0010] Furthermore, as in Fig. Figure 2 shows a power supply line 60 for supplying power to the semiconductor chip 30 and the substrate 20, which is electrically connected to each other via a wire 20 or a soldered connection. At this point, an area is required for the connection of the substrate 20 to the power supply line 60, and therefore the size of the power module can be increased.

[0011] To prevent damage to the semiconductor chip during the bonding process, a solder bonding method is used. This solder bond can break if excessive heat is applied during a subsequent process, including subsequent soldering.

[0012] One aspect of the present invention is to provide a double-sided cooling-type power module which can be suitably manufactured as a result of a simple structure, can be produced with a small volume and in which the bonding reliability can be improved, and to specify a manufacturing method for it.

[0013] Another aspect of the present invention is to provide a method for packaging power supply chips for a motor in a hybrid vehicle. When multiple soldering stages are used to manufacture a single package of power supply chips, solder bonding can be compromised by excessive heat during a subsequent soldering process. In embodiments, a lead (610, 620, 630) of the power supply chip is bonded to a ceramic heat dissipation substrate (100, 200) using a brazing process to create a brazed bond (B in Fig. 5) to form. After the brazing process, the power supply chip (310, 320) is soldered to the lead at a location that overlaps the brazed bond (B), viewed in a direction perpendicular to the main surface of the substrate, to form a soldered bond (S) in Fig. 3) to form. In embodiments, no subsequent soldering process or heating process after the soldering process is applied to form the soldered bond (S) of the power supply chip.

[0014] In accordance with one embodiment of the present invention, a double-sided cool-type power module is provided in which a pair of semiconductor chips are arranged between an upper substrate and a lower substrate, the double-sided cool-type power module comprising: output leads configured to be located on a lower surface of the upper substrate and each connected to the pair of semiconductor chips; a positive lead configured to be located on one side of an upper surface of the lower substrate to be connected to any semiconductor chip selected from the pair of semiconductor chips; and a negative lead configured to be located on the other side of the upper surface of the lower substrate to be connected to the other semiconductor chip of the pair of semiconductor chips.

[0015] A brazing bond is performed between the upper substrate and the output lead, the lower substrate and the positive lead, or the lower substrate and the negative lead, and a soldering bond is performed between the semiconductor chip and the output lead, between the semiconductor chip and the positive lead, and between the semiconductor chip and the negative lead.

[0016] The lower substrate comprises a lower ceramic layer made of a ceramic material, a positive terminal layer arranged on one side of an upper surface of the lower ceramic layer to be bonded to the positive terminal lead, and a negative terminal layer arranged on the other side of the upper surface of the lower ceramic layer to be bonded to the negative terminal lead, and the positive terminal layer and the negative terminal layer are arranged to be insulated from each other.

[0017] The double-sided cooling-type power module may further comprise: a first signal input configured to be connected to the first semiconductor chip to send and receive a control signal, and a second signal input configured to be connected to the second semiconductor chip to send and receive the control signal, wherein the semiconductor chip comprises a first semiconductor chip located between the output input and the positive input, and a second semiconductor chip located between the output input and the negative input.

[0018] The double-sided cooling-type power module may further include: a first spacer configured to be positioned between the first semiconductor chip and the output terminal lead, and a second spacer configured to be positioned between the second semiconductor chip and the negative terminal lead.

[0019] A solder bond can be made between the positive lead and the first semiconductor chip or between the first semiconductor chip and the first spacer; a solder bond can be made between the output lead and the second semiconductor chip or between the second semiconductor chip and the second spacer; a brazed bond can be made between the upper substrate and the output lead or between the output lead and the first spacer; a brazed bond can be made between the lower substrate and the negative lead or between the negative lead and the second spacer; and a brazed bond can be made between the lower substrate and the positive lead.

[0020] In accordance with another embodiment of the present invention, a manufacturing method for a double-sided cooling-type power module is provided, wherein a pair of semiconductor chips are arranged between an upper substrate and a lower substrate, the manufacturing method comprising: an assembly step for an upper module for arranging an output lead on a lower surface of the upper substrate and for arranging a first spacer on a lower surface of the output lead; an assembly step for a lower module for arranging a positive lead on one side of an upper surface of the lower substrate, for arranging a negative lead on the other side of the upper surface of the lower substrate, and for arranging a second spacer on the upper surface of the negative lead;and a module coupling step for arranging a first semiconductor chip between the first spacer and the positive lead and for arranging a second semiconductor chip between the second spacer and the negative lead to establish a coupling between the first semiconductor chip and the second semiconductor chip.

[0021] During the assembly step for the upper module, a hard solder bond is performed between the upper substrate and the output connection lead or between the output connection lead and the first spacer.

[0022] In the assembly step for the lower module, a hard solder bond is performed between the lower substrate and the negative terminal lead, between the negative terminal lead and the second spacer, and between the lower substrate and the positive terminal lead.

[0023] In the module coupling step, a solder bond is performed between the positive lead and the first semiconductor chip or between the first semiconductor chip and the first spacer, and the solder bond is performed between the output lead and the second semiconductor chip or between the second semiconductor chip and the second spacer. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings show: Fig. 1 a diagram representing a double-sided cooling-type power module; Fig. 2 a diagram representing an external appearance in which a lower substrate and a power supply line of the double-sided cooling type power module are connected; Fig. 3 a diagram which represents an external appearance of a double-sided cooling-type power module in accordance with an embodiment of the present invention; Fig. 4 a diagram representing an external appearance in which a lower substrate and a power supply line of the double-sided cooling-type power module according to an embodiment of the present invention are connected to each other; and Fig. 5 a diagram which represents an appearance of an intermediate structure of the double-sided cooling-type power module manufactured in accordance with an embodiment of the present invention. DESCRIPTION OF EXECUTION FORMS

[0025] Technologies used herein serve to illustrate embodiments of the present invention and do not limit the present invention. Singular terms used herein include plural forms unless they clearly indicate an opposite meaning. The term "including" used in this description specifically indicates particular properties, regions, integers, steps, operations, elements, and / or components, and is not intended to exclude the presence or addition of other properties, regions, integers, steps, operations, elements, components, and / or groups thereof.

[0026] All terms, including technical and scientific terms, used herein have the same meaning as those generally understood by a person skilled in the art in the technical field to which the present invention relates, unless otherwise defined. Terms defined in a commonly used dictionary shall additionally be interpreted as having the meaning appropriate to the prior art document and the content currently disclosed, and shall not be interpreted as having an ideal or formal meaning, unless otherwise defined.

[0027] Below, with reference to the accompanying drawings, a double-sided cooling-type power module and a manufacturing method for it are described in accordance with embodiments of the present invention.

[0028] As in Fig. 3 and Fig. Figure 4 shows a double-sided cooling-type power module configured according to an embodiment of the present invention to comprise a structure in which a pair of semiconductor chips 300 are arranged in parallel between an upper substrate 100 and a lower substrate 200, an output connection lead 610 is arranged between the upper substrate 100 and the semiconductor chip 300, a positive connection lead 620 is arranged between one side of the lower substrate 200 and the semiconductor chip 300, and a negative connection lead 630 is arranged between the other side of the lower substrate 200 and the semiconductor chip 300.

[0029] In Fig. 1. An element 60, which may correspond to the aforementioned output lead 610, a positive lead 620 and a negative lead 630 are bonded separately to the upper substrate 100 or the lower substrate 200 by a wire or a soldering process, but in accordance with an embodiment of the present invention, these parts are arranged between the semiconductor chip 300 and the upper and lower substrates in order to reduce an area or region of the upper and lower substrates.

[0030] In this case, the pair of semiconductor chips 300 can further comprise a first semiconductor chip 310 connected to the negative terminal 630 and a second semiconductor chip 320 connected to the positive terminal 620, a first signal line 640 connected to the first semiconductor chip 310 to send and receive a signal, and a second signal line 650 connected to the second semiconductor chip 320 to send and receive a signal.

[0031] In addition, a first spacer 410 can be arranged to provide a mounting location for a first wire 720, which connects the first semiconductor chip 310 and the first signal line 640. Similarly, a second spacer 420 can be arranged to provide a mounting location for a second wire 710, which connects the second semiconductor chip 320 and the second signal line 650.

[0032] For the sake of simplicity, the stacked configuration in which the upper substrate 100, the output lead 610, the first spacer 410, the first semiconductor chip 310, the positive lead 620 and the lower substrate 200 are arranged in succession is referred to below as a first switch, and the stacked configuration in which the upper substrate 100, the output lead 610, the second semiconductor chip 320, the second spacer 420, the negative lead 630 and the lower substrate 200 are arranged in succession is referred to as a second switch.

[0033] The first switch and the second switch differ in that the mounting directions of the semiconductor chip 300 and the spacer 400 are opposite to each other, with their input terminals, i.e. the positive terminal lead 620 and the negative terminal lead 630, arranged in one direction and an output terminal, i.e. the output terminal lead 610, arranged in the other direction to simplify the construction of the upper and lower substrates. That is, the double-sided cooling-type power module has a problem in that the input and output connections are distributed on the upper and lower substrates, and therefore its construction is complicated and the manufacturing process, such as the application of a separate conductive line for electrically connecting them, is complicated, but the construction of the double-sided cooling-type power module can be simplified simply by making the mounting direction of the pair of semiconductor chips 300 opposite to each other.

[0034] For a more precise description of the upper and lower substrates, it should be noted that the upper and lower substrates are divided into three layers. That is, the upper substrate 100 is configured to include an upper heat dissipation layer 110 on its outer surface, an upper ceramic layer 120 in a central section thereof, and an output terminal layer 130 on its inner surface; and the lower substrate 200 is configured to include a lower heat dissipation layer 210 on its outer surface, a lower ceramic layer 220 in a central section thereof, and a positive terminal layer 230 and a negative terminal layer 240 on their inner surfaces.

[0035] In this case, the positive terminal layer 230 is bonded to the positive terminal supply line 620, the negative terminal layer 240 is bonded to the negative terminal supply line 630, and the positive terminal layer 230 and the positive terminal supply line 620 are preferably arranged such that they are insulated from the negative terminal layer 420 and the negative terminal supply line 630.

[0036] That is, a separate insulator is inserted between the positive terminal layer 230 and the positive terminal supply line 630 and between the negative terminal layer 240 and the negative terminal supply line 630, or these parts are arranged to be separate from each other and can then be insulated by encapsulation.

[0037] However, since the output terminal 610, the positive terminal 620 and the negative terminal 630 are built into the stack structure, the number of layers is increased more than the double-sided cooling type power module, so the bonding reliability can only be reduced as a result of solder bonding.

[0038] Therefore, the bonding of the remaining sections, apart from the bonding of the semiconductor chip 300, is sensitive to heat under the brazing bond.

[0039] That is, the brazing bond is carried out between the output connection layer 130 of the upper substrate 100 and the output connection lead 610, between the output connection lead 610 and the first spacer 410, between the positive connection layer 230 of the lower substrate 200 and the positive connection lead 620, between the negative connection layer 240 of the lower substrate 200 and the negative connection lead 630, and between the negative connection lead 630 and the second spacer 420, thereby obtaining the high bonding strength or connection strength.

[0040] Next, a solder bonding operation S is performed when the first semiconductor chip 310, which is bonded to the first spacer 410 and the positive terminal lead 620, and the second semiconductor chip 320, which is bonded to the second spacer 420 and the output terminal lead 610, are as before.

[0041] Brazing is carried out at a temperature of approximately 450 °C or more, for example at a temperature of approximately 800 °C when an adhesive such as Ag-Sn is used, and therefore the brazed bond cannot be weakened during the execution of a soldering bond, e.g. a soft soldering, which is carried out at a temperature of 300 °C.

[0042] Furthermore, a manufacturing process for a double-sided cooling-type power module in accordance with an embodiment of the present invention is configured to include an assembly step for an upper module, an assembly step for a lower module, and a module coupling step.

[0043] At this point, an external appearance is achieved, in which the assembly step for the upper module and the assembly step for the lower module end, and then the semiconductor chip 300 is attached in the module coupling step. Fig.5 shown.

[0044] In the assembly step for the upper module, the output connection lead 610 is positioned on a lower surface of the upper substrate 100, and the first spacer 410 is positioned on a lower surface of the output connection lead 610. At this point, the respective components are subjected to brazing.

[0045] In the assembly step for the lower module, the positive lead 620 is located on one side of the upper surface of the lower substrate 200, the negative lead 630 is located on the other side, and the second spacer 420 is located on the negative lead 630. At this point, the respective components suffer disadvantages due to the brazing bond.

[0046] Next, in the module coupling step, the first semiconductor chip 310 and the second semiconductor chip 320 are positioned between the components that were assembled in the assembly step of the upper module and the assembly step of the lower module, and then undergo solder bonding.

[0047] The double-sided cooling-type power module and a manufacturing method therefor in accordance with an embodiment of the present invention exhibit the following effects.

[0048] Firstly, it is possible to provide the power module, which has a simpler structure, by using a chip application that has a top-bottom rotary design.

[0049] Secondly, it is possible to simplify the manufacturing process by simplifying the design of the power module.

[0050] Thirdly, it is possible to reduce the overall volume of the power module by eliminating the bonded section between the substrate and the power supply line.

[0051] Fourthly, it is possible to improve the bond strength of the stack structure of the power module by using the brazing bonding process.

Claims

[1] Double-sided cooling-type power module in which a pair of semiconductor chips (310, 320) are arranged between an upper substrate (100) and a lower substrate (200), the double-sided cooling-type power module comprising: Output connection leads (610) are configured to be arranged on a lower surface of the upper substrate (100) and each connected to the pair of semiconductor chips (310, 320); a positive terminal lead (620) configured to be located on one side of an upper surface of the lower substrate (200) for connection to any semiconductor chip selected from the pair of semiconductor chips (310, 320); and a negative terminal lead (630) configured to be located on the upper side of the upper surface of the lower substrate (200) to be connected to the other semiconductor chip of the pair of semiconductor chips (310, 320), wherein a brazing bond is made between the upper substrate (100) and the output connection lead (610), the lower substrate (200) and the positive connection lead (620), or the lower substrate (200) and the negative connection lead (630), and a solder bond is made between the semiconductor chip and the output lead (610), between the semiconductor chip and the positive lead (620), and between the semiconductor chip and the negative lead (630), wherein the lower substrate (200) comprises a lower ceramic layer (220) made of a ceramic material, a positive terminal layer (230) arranged on one side of an upper surface of the lower ceramic layer (220) to be bonded to the positive terminal lead (620), and a negative terminal layer (240) arranged on the other side of the upper surface of the lower ceramic layer (220) to be bonded to the negative terminal lead (630), and wherein the positive terminal layer (230) and the negative terminal layer (240) are arranged to be isolated from each other. [2] Double-sided cooling-type power module according to claim 1, further comprising: a first signal input (640) configured to be connected to a first semiconductor chip (310) to send and receive a control signal, and a second signal input (650) configured to be connected to a second semiconductor chip (320) to send and receive the control signal, wherein the semiconductor chip (300) comprises the second semiconductor chip (320) which is arranged between the output terminal (610) and the positive terminal (620), and the first semiconductor chip (310) which is arranged between the output terminal (610) and the negative terminal (630). [3] Double-sided cooling-type power module according to claim 2, further comprising: a first spacer (410) which is configured to be positioned between the first semiconductor chip (310) and the output connection lead (610), and a second spacer (420) which is configured to be positioned between the second semiconductor chip (320) and the positive terminal lead (620). [4] Double-sided cooling-type power module according to claim 3, wherein a solder bond is provided between the negative terminal lead (630) and the first semiconductor chip (310) or between the first semiconductor chip (310) and the first spacer (410), the solder bonding is carried out between the output connection lead (610) and the second semiconductor chip (320) or between the second semiconductor chip (320) and the second spacer (420), a brazing bond is made between the upper substrate (100) and the output connection lead (610) or between the output connection lead (610) and the first spacer (410), the brazing bond is made between the lower substrate (200) and the positive terminal lead (620) or between the positive terminal lead (620) and the second spacer (420), and the brazing bond is made between the lower substrate (200) and the negative connection lead (630). [5] Manufacturing process for a double-sided cooling-type power module in which a pair of semiconductor chips (310, 320) are arranged between an upper substrate (100) and a lower substrate (200), the manufacturing process comprising: an assembly step for an upper module to arrange an output connection lead (610) on a lower surface of the upper substrate (100) and to arrange a first spacer (410) on a lower surface of the output connection lead (610); an assembly step for a lower module for arranging a positive terminal lead (620) on one side of an upper surface of the lower substrate (200), for arranging a negative terminal lead (630) on the other side of the upper surface of the lower substrate (200), and for arranging a second spacer (420) on an upper surface of the positive terminal lead (620); and a module coupling step for arranging a first semiconductor chip (310) between the first spacer (410) and the negative terminal (630) and for arranging a second semiconductor chip (320) between the second spacer (420) and the positive terminal (620) to establish a coupling between the first semiconductor chip (310) and the second semiconductor chip (320), wherein in the assembly step of the upper module a hard solder bond is performed between the upper substrate (100) and the output connection lead (610) or between the output connection lead (610) and the first spacer (410), wherein in the assembly step of the lower module a hard solder bond is made between the lower substrate (200) under the positive connection lead (620), between the positive terminal supply line (620) and the second spacer (420) or between the lower substrate (200) and the negative terminal supply line (630), wherein in the module coupling step a solder bond is performed between the negative terminal lead (630) and the first semiconductor chip (310) or between the first semiconductor chip (310) and the first spacer (410), and the solder bonding is carried out between the output connection lead (610) and the second semiconductor chip (320) or between the second semiconductor chip (320) and the second spacer (420), wherein the lower substrate (200) comprises a lower ceramic layer (220) made of a ceramic material, a positive terminal layer (230) arranged on one side of an upper surface of the lower ceramic layer (220) to be bonded to the positive terminal lead (620), and a negative terminal layer (240) arranged on the other side of the upper surface of the lower ceramic layer (220) to be bonded to the negative terminal lead (630), and wherein the positive terminal layer (230) and the negative terminal layer (240) are arranged to be isolated from each other.

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