SEMICONDUCTOR DEVICE ACCOMODATING SEMICONDUCTOR MODULE WITH HEAT RADIATION STRUCTURE

• US 20110242761A1
• Filed: 03/29/2011
• Published: 10/06/2011
• Est. Priority Date: 03/30/2010
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: TONOMOTO, Masaya
• Granted Patent: US 8,363,403 B2
• Time in Patent Office: Days
• US Class Current: 361/702
• CPC Class Codes: H01L 2224/291 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/33181 On opposite sides of the body
• CPC Class Codes: H01L 23/4012 for stacked arrangements of a plurality of semiconductor devices assemblies per se H01L25/00
• CPC Class Codes: H01L 23/4334 Auxiliary members in encapsulations H01L23/49568 takes precedence
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• CPC Class Codes: H01L 25/072 the devices being arranged next to each other
• CPC Class Codes: H01L 25/117 Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]

Abstract

As a result of a lower arm side having a small thermal resistance being positioned downstream of the coolant flow, cooling efficiency of the lower arm positioned on the downstream side of the coolant flow becomes higher than that of an upper arm positioned on an upstream side. Hence, rise in coolant temperature on the upstream side can be suppressed, and the first and second semiconductor chips disposed upstream and downstream can be effectively cooled. Alternatively, even when the coolant temperature rises on the upstream side, the first and second semiconductor chips disposed upstream and downstream can be effectively cooled by sufficient cooling being performed on the downstream side based on the high cooling efficiency. Therefore, the rise in semiconductor chip temperature on the downstream side to a temperature higher than that on the upstream side can be suppressed.

Claims

1. A semiconductor device comprising:

a semiconductor module including

a first semiconductor chip configuring an upper arm and a second semiconductor chip configuring a lower arm, each having a front surface and a back surface, and each in which a semiconductor power element is formed,

a first heat sink disposed on, the back surface side of the first semiconductor chip,

a second heat sink disposed on the front surface side of the first semiconductor chip and the back surface side of the second semiconductor chip,

a third heat, sink disposed on the front surface side of the second semiconductor chip, and

a resin sealing section that seals the first and second semiconductor chips and the first to third heat sinks, in which

the surfaces of the first to third heat sinks on the side opposite of the first and second semiconductor chips serve as heat radiating surfaces and are exposed from the resin sealing section; and

a cooling mechanism including a coolant passage through which a coolant flows, that comes into contact with the heat radiating surfaces of the first to third heat sinks exposed from the resin sealing section by sandwiching the semiconductor module, and cools the first and second semiconductor chips included in the semiconductor module, wherein

of the upper arm and the lower arm, the arm with a greater combined value of thermal resistances from the first or second semiconductor chip to the heat radiating surfaces of the first to third heat sinks is disposed on an upstream side of a coolant flow flowing through the coolant passage, and the arm with the smaller combined value of the thermal resistances is disposed on a downstream side.

2. The semiconductor device according to claim 1, wherein:

the first semiconductor chip has a first metal block formed on the front surface side thereof, the first metal block being of a size smaller than that of the first semiconductor chip and being bonded to an active area of the first semiconductor chip through which a current of the semiconductor power element flows, and the second heat sink is disposed on the side of the first metal block opposite to the first semiconductor chip; and

the second semiconductor chip has a second metal block formed on the front surface side thereof, the second metal block being of a size smaller than that of the second semiconductor chip and being bonded to an active area of the second semiconductor chip through which a current of the semiconductor power element flows, and the third heat sink is disposed on the side of the second metal block opposite to the second semiconductor chip.

3. The semiconductor device according to claim 1, wherein;

the first heat sink and the third heat sink are of equal size in an array direction of the upper arm and the lower arm, and a length of the second heat sink is longer than a combined length of the first heat sink and the third heat sink; and

the upper arm is disposed on the upstream side of the coolant flow flowing through the coolant passage and the lower arm is disposed further downstream from the upper arm.

4. The semiconductor device according to claim 2, wherein;

the first heat sink and the third heat sink are of equal size in an array direction of the upper arm and the lower arm, and a length of the second heat sink is longer than a combined length of the first heat sink and the third heat sink; and

the upper arm is disposed on the upstream side of the coolant flow flowing through the coolant passage and the lower arm is disposed further downstream from the upper arm.

5. The semiconductor device according to claim 3, wherein the third heat sink is of a size longer than the size of the first heat sink in an array direction of the upper arm and the lower arm.

6. The semiconductor device according to claim 1, wherein:

the first heat sink is of a size longer than the size of the third heat sink in an array direction of the upper arm and the lower arm; and

the lower arm is disposed on an upstream side of a coolant flow flowing through the coolant passage, and the upper arm is disposed further downstream from the lower arm.

7. The semiconductor device according to claim 2, wherein:

the first heat sink is of a size longer than the size of the third heat sink in an array direction of the upper arm and the lower arm; and

the lower arm is disposed on an upstream side of a coolant flow flowing through the coolant passage, and the upper arm is disposed further downstream from the lower arm.

8. A semiconductor device comprising:

a semiconductor module including

a first semiconductor chip configuring an upper arm and a second semiconductor chip configuring a lower arm, each having a front surface and a back surface,

and each in which a semiconductor power element is formed,

a first heat sink disposed on the front surface side of the first semiconductor chip,

a second heat sink disposed on the back surface side of the first semiconductor chip,

a third heat sink disposed on the front surface side of the second semiconductor chip,

a fourth heat sink disposed on the back surface side of the second semiconductor chip, and

a resin sealing section that seals the first and second semiconductor chips and the first to fourth heat sinks, in which

the surfaces of the first to fourth heat sinks on the side opposite of the first and second semiconductor chips serve as heat radiating surfaces and are exposed from the resin sealing section; and

a cooling mechanism including a coolant passage through which a coolant flows, that comes into contact with the heat radiating surfaces of the first to fourth heat sinks exposed from the resin sealing section by sandwiching the semiconductor module, and cools the first and second semiconductor chips included in the semiconductor module, wherein

of the upper arm and the lower arm, the arm with a greater combined value of thermal resistances from the first or second semiconductor chips to the heat radiating surfaces of the first to fourth heat sinks is disposed on an upstream side of a coolant flow flowing through the coolant passage, and the arm with the smaller combined value of the thermal resistances is disposed on a downstream side.

9. The semiconductor device according to claim 8, wherein:

the first semiconductor chip has a first metal block formed on the front surface side thereof the first metal block being of a size smaller than that of the first semiconductor chip and being bonded to an active area of the first semiconductor chip through which a current of the semiconductor power element flows, and the first heat sink is disposed on the side of the first metal block opposite to the first semiconductor chip; and

the second semiconductor chip has a second metal block formed on a front surface side thereof, the second metal block being of a size smaller than that of the second semiconductor chip and being bonded to an active area of the second semiconductor chip through which a current of the semiconductor power element flows, and the third heat sink is disposed on the side of the second metal block opposite to the second semiconductor chip.

10. The semiconductor device according to claim 8, wherein;

either one of the first heat sink and the second heat sink on the upper arm side, and the third heat sink and the fourth heat sink on the lower arm side is of a size longer than that of the other in an array direction of the upper arm and the lower arm; and

of the upper arm and the lower arm, the arm having the longer size is disposed on the downstream side of the coolant flow flowing through the coolant passage, and the other arm is disposed further upstream thereof.

11. The semiconductor device according to claim 9, wherein;

either one of the first heat sink and the second heat sink on the upper arm side, and the third heat sink and the fourth heat sink on the lower arm side is of a size longer than that of the other in an array direction of the upper arm and the lower arm; and

of the upper arm and the lower arm, the arm having the longer size is disposed on the downstream side of the coolant flow flowing through the coolant passage, and the other arm is disposed further upstream thereof.