US20110024091A1 - Cooling apparatus for semiconductor component - Google Patents

Cooling apparatus for semiconductor component Download PDF

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Publication number
US20110024091A1
US20110024091A1 US12/835,298 US83529810A US2011024091A1 US 20110024091 A1 US20110024091 A1 US 20110024091A1 US 83529810 A US83529810 A US 83529810A US 2011024091 A1 US2011024091 A1 US 2011024091A1
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United States
Prior art keywords
flow path
coolant inlet
coolant
cooling apparatus
cooling
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Abandoned
Application number
US12/835,298
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English (en)
Inventor
Jaewon Kim
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Add Blue Corp Ltd
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Add Blue Corp Ltd
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Assigned to ADD BLUE CORPORATION LTD. reassignment ADD BLUE CORPORATION LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KIM, JAEWON
Publication of US20110024091A1 publication Critical patent/US20110024091A1/en
Assigned to ADD BLUE CORPORATION LTD. reassignment ADD BLUE CORPORATION LTD. CORRECTIVE ASSIGNMENT TO CORRECT THE ASSIGNEE'S COUNTRY OF RESIDENCE PREVIOUSLY RECORDED ON REEL 024681 FRAME 0130. ASSIGNOR(S) HEREBY CONFIRMS THE ASSIGNEE'S COUNTRY OF RESIDENCE IS REPUBLIC OF KOREA. Assignors: KIM, JAEWON
Abandoned legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
    • F28F3/02—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations
    • F28F3/04—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations the means being integral with the element
    • F28F3/042—Elements or assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with recesses, with corrugations the means being integral with the element in the form of local deformations of the element
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
    • F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/46—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids
    • H01L23/473—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements involving the transfer of heat by flowing fluids by flowing liquids
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0028—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for cooling heat generating elements, e.g. for cooling electronic components or electric devices
    • F28D2021/0029—Heat sinks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001—Technical content checked by a classifier
    • H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Definitions

  • the present invention relates to a cooling apparatus for semiconductor components, and more particularly, to a cooling apparatus for semiconductor components having an optimal coolant inlet flow path structure capable of improving cooling efficiency and reducing resistance to coolant flow.
  • Korean Patent Application No. 10-2009-0069794 on Jul. 30, 2009 in the Korean Intellectual Property Office (KIPO), the disclosure of which is incorporated herein by reference in its entirety.
  • Typical mechanism for removing heat is a heat-sink having a group of cooling fins is attached to a semiconductor chip or a ceramic substrate.
  • Examples of various variables related to the heat dissipation performance of a cooling apparatus having a heat sink include the shape and length of a cooling fin, the area of a heat-transfer surface of the cooling fin, the inlet geometry of a coolant and flow field, etc.
  • a cooling apparatus for a semiconductor component should be configured to make a semiconductor component capable of operating at a predetermined temperature or lower when maximum power is applied during a predetermined time period after the semiconductor component reaches temperature saturation by continuous rated power. To this end, all various variables related to the heat dissipation performance should be appropriately adjusted.
  • the shape of a coolant inlet flow path is examined the effects on cooling efficiency and resistance to coolant flow.
  • the inlet geometry of a cooling system is designed in a diffuser shape.
  • a reverse flow or stall phenomenon depends on a diffuser divergence angle and whether a diffuser shape is a cone shape or a straight pipe, which affects the stability degree of flow.
  • a decrease in a cross-sectional area causes an increase in the kinetic energy and a decrease in the pressure energy (Bernoulli's theorem).
  • a coolant inlet flow path structure having a structure in which, in order to enable coolant flowing into a cooling apparatus for a semiconductor component to overcome the resistance of cooling fins for heat transfer in a flow path, the cross-sectional area of the flow path is enlarged to compensate pressure.
  • reserve flow and vortex occurs, the effect is less dominant in improving cooling efficiency and reducing resistance to coolant flow. For this reason, it is difficult to form a coolant inlet flow path having a high cooling efficiency and small resistance to flow.
  • a cooling apparatus for a semiconductor component having a coolant inlet flow path on a coolant flow path connecting a coolant inlet and a coolant outlet, the coolant inlet flow path having a diffuser shape in which its cross-sectional area increases from the coolant inlet to a portion where cooling fins start to appear.
  • the coolant inlet flow path meets the following equation:
  • ⁇ is the radius of the diffuser
  • D is the diameter of the coolant inlet
  • x is a distance from the coolant inlet toward the cooling fins
  • ⁇ is an expansion slope coefficient of the diffuser in radians
  • sine of ( ⁇ A) is 1.
  • the range of x may be 0 ⁇ x ⁇ 6.5D.
  • the range of A may be 3D ⁇ A ⁇ 3.5D and the range of a may meet ⁇ /7D ⁇ /6D.
  • a number of cooling fins may be grouped to form a heat sink in the coolant flow path.
  • the heat sink may be connected to a semiconductor component corresponding to the heat sink.
  • a cooling apparatus for a semiconductor component including: a main body comprising a coolant flow path extending from a coolant inlet to a coolant outlet; and a number of cooling fins formed in the coolant inlet flow path to cross the coolant flow path.
  • the coolant flow path includes a coolant inlet flow path formed in a diffuser shape whose cross-sectional area increases from the coolant inlet to a portion where the cooling fins start to appear and whose profile is a curve.
  • the curve may be a sine function graph shape.
  • a number of cooling fins may be grouped to form a heat sink in the coolant flow path.
  • the heat sink may be connected to a semiconductor component corresponding to the heat sink.
  • the diffuser-shaped coolant inlet flow path extending from the coolant inlet to the cooling fins is designed in an optimal shape, it is possible to improve cooling efficiency and to reduce resistance to coolant flow.
  • FIG. 1 is a perspective view schematically illustrating a cooling apparatus for semiconductor components according to an exemplary embodiment of the present invention
  • FIG. 2 is a planar cross-sectional view illustrating the internal of the cooling apparatus shown in FIG. 1 ;
  • FIG. 3 is a drawing illustrating a variation in a flow field in cases (a) and (b) of where the coolant inlet flow path CP has different curved expanding pipe shapes;
  • FIG. 4 is a drawing illustrating a variation in a flow field in cases (a) and (b) of where the coolant inlet flow path CP has different linear expanding pipe shapes;
  • FIG. 5 is a drawing illustrating a temperature distribution around individual heat sinks when the shape of the coolant inlet flow path CP is a curved expanding pipe;
  • FIG. 6 is a drawing illustrating a temperature distribution around individual heat sinks when the shape of the coolant inlet flow path CP is a linear expanding pipe;
  • FIG. 7 is a plot illustrating temperature variations during a time period when the maximum continuous rated power is applied to comparison examples having various shapes of the coolant inlet flow paths.
  • FIG. 8 is a plot illustrating an equation representing the shape of the coolant inlet flow path CP according to the exemplary embodiment of the present invention.
  • FIG. 1 is a perspective view schematically illustrating a cooling apparatus for semiconductor components according to an exemplary embodiment of the present invention.
  • FIG. 2 is a planar cross-sectional view illustrating the internal of the cooling apparatus in shown FIG. 1 .
  • a cooling apparatus 100 has a coolant inlet 120 formed on one side of a main body 110 , an coolant outlet 130 formed on another side of the main body 110 , and a coolant flow path 125 connecting the coolant inlet 120 and the coolant outlet 130 .
  • a number of semiconductor components 140 are attached to the top surface of the main body 110 .
  • a coolant flow path 125 is formed to extend from the coolant inlet 120 to the coolant outlet 130 .
  • a coolant flow path 125 there are provided a number of heat sinks H 1 , H 2 , H 3 , H 4 , H 5 , and H 6 including cooling fin groups.
  • Each of the cooling fin groups is composed of a number of cooling fins F which are provided to cross the coolant flow path 125 and are connected to the semiconductor components 140 .
  • the coolant flow path comprise a coolant inlet flow path CP having a diffuser shape, in which its cross-sectional area increases from the coolant inlet to a portion where cooling fins F of the heat sink H 1 (hereinafter, referred to as a first heat sink) start to appear.
  • a coolant inlet flow path CP having a diffuser shape, in which its cross-sectional area increases from the coolant inlet to a portion where cooling fins F of the heat sink H 1 (hereinafter, referred to as a first heat sink) start to appear.
  • FIG. 3 is a drawing illustrating a variation in a flow field in cases (a) and (b) of where the coolant inlet flow path CP has different curved expanding pipe shapes.
  • the measurement location y represents a distance from the top surface of the heat sink H 1 , having the cooling fins F attached thereto, to the bottom of the heat sink H 1 .
  • FIG. 4 is a drawing illustrating a variation in a flow field in cases (a) and (b) of where the coolant inlet flow path CP has different linear expanding pipe shapes.
  • the measurement location y represents a distance from the top surface of the heat sink H 1 , having the cooling fins F attached thereto, to the bottom of the heat sink H 1 .
  • FIG. 5 is a drawing illustrating a temperature distribution around individual heat sinks H 1 , H 2 , H 3 , H 4 , H 5 , and H 6 provided in a coolant flow path 125 of a cooling apparatus when the shape of the coolant inlet flow path CP is a curved expanding pipe.
  • FIG. 6 is a drawing illustrating a temperature distribution around individual heat sinks H 1 , H 2 , H 3 , H 4 , H 5 , and H 6 provided in a coolant flow path 125 of a cooling apparatus when the shape of the coolant inlet flow path CP is a linear expanding pipe.
  • numerical values inside the heat sinks represent temperatures (° C.).
  • the temperatures around the individual heat sinks when the shape of the coolant inlet flow path CP is a curved expanding pipe are lower than those when the shape of the coolant inlet flow path CP is a linear expanding pipe.
  • Table 1 shows a cooling performance comparison between the case where the shape of the coolant inlet flow path CP is a curved expanding pipe and the case where the shape of the coolant inlet flow path CP is a linear expanding pipe.
  • Numerical values in Table 1 are checked results on whether a temperature of a power semiconductor component is equal to or lower than a target temperature (120° C.) due to heat dissipation on a first condition that the maximum rated power is applied 30 seconds after a power semiconductor component of an IGBT (integrated gate bipolar transistor module for MCU (motor control unit) and HDC (high side DC/DC converter) reaches temperature saturation by continuous rated power and on a second condition that electrical energy exceeding maximum rated power by 30% is applied 30 seconds after a power semiconductor component of an IGBT module for MCU (motor control unit) and HDC (high side DC/DC converter) reaches temperature saturation by continuous rated power.
  • the IGBT module is a power module of a driving system mounted a 40 kw diesel engine-motor hybrid electrical vehicle (HEV).
  • the coolant inlet flow path CP when the shape of the coolant inlet flow path CP is a curved expanding pipe, the coolant inlet flow path CP is at temperatures remarkably lower than the target temperature (120° C.) due to heat dissipation on both of the first and second conditions and also has the highest temperature remarkably lower than when the shape of the coolant inlet flow path CP is a linear expanding pipe.
  • the case where the shape of the coolant inlet flow path CP is a curved expanding pipe is much more effective than the case where the shape of the coolant inlet flow path CP is a linear expanding pipe in that an error between a result obtained by fabricating a trial product and performing performance estimation and a temperature distribution of an actual product is about maximum 7% and design considering a safety factor is inevitable in the case where the shape of the coolant inlet flow path CP is a linear expanding pipe.
  • FIG. 7 is a graph illustrating temperature variations during a time period when the maximum continuous rated power is applied after a power semiconductor component of an IGBT module for MCU (motor control unit) and HDC (high side DC/DC converter), which is a power module of a driving system, reaches temperature saturation by continuous rated power, in comparison examples having various shapes of coolant inlet flow paths CP.
  • IGBT module for MCU motor control unit
  • HDC high side DC/DC converter
  • first to fifth comparison examples represent cases where the profiles of coolant inlet flow paths CP are a linear function graph shape, a cosine function graph shape, an ellipse function graph shape, a sine function graph shape, and a parabolic function graph shape, respectively.
  • the fourth comparison example in which the profile of the coolant inlet flow path CP is a sine function graph shape has the lowest pressure resistance and the highest cooling performance.
  • the shape of the coolant inlet flow path CP is limited as follows.
  • the shape of the coolant inlet flow path CP is determined to be a shape meeting the following Equation 1.
  • A means an x value of an inflexion point in a sine function appearing in Equation 1.
  • Equation 1 x meets 0 ⁇ x ⁇ 6.5D and ‘A’ meets 3D ⁇ A ⁇ 3.5D.
  • the shape of the coolant inlet flow path CP greatly varies according to the ‘A’ value (the location of the inflexion point).
  • the ‘A’ value the location of the inflexion point.
  • the cross-sectional area of the flow path may be rapidly enlarged, and when the ‘A’ value is large, the cross-sectional area of the flow path may be enlarged at a location too far from the coolant inlet. For this reason, it is required to appropriately select the ‘A’ value.
  • the ‘A’ value is designed in a range of 3D ⁇ A ⁇ 3.5D. In this case, ⁇ meets ⁇ /7D ⁇ /6D.
  • the following Table 2 shows a cooling performance comparison according to upper and lower limits of x. Numerical values in Table 2 are checked results on whether a temperature of a power semiconductor component is equal to or lower than a target temperature (120° C.) due to heat dissipation on the first condition that the maximum rated power is applied 30 seconds after a power semiconductor component of an IGBT module for MCU (motor control unit) and HDC (high side DC/DC converter) reaches temperature saturation by continuous rated power and on the second condition that electrical energy exceeding the maximum rated power by 30% is applied 30 seconds after a power semiconductor component of an IGBT module for MCU (motor control unit) and HDC (high side DC/DC converter) reaches temperature saturation by continuous rated power.
  • the IGBT module is a power module of a driving system mounted a 40 kw diesel engine-motor hybrid electrical vehicle (HEV).
  • the inventive example having x in a range of 0 ⁇ x ⁇ 6.5D is at temperatures remarkably lower than the target temperature (120° C.) due to heat dissipation on both of the first and second conditions, as compared with the first to third experimental examples. Therefore, it can be seen that the cooling performance of the inventive example is the most effective.
  • cooling performance is the most superior when the range of x in a range of 0 ⁇ x ⁇ 6.5D in that an error between a result obtained by fabricating a trial product and performing performance estimation and a temperature distribution of an actual product is about maximum 7% and thus design considering a safety factor is inevitable in the cases of the first to third experimental examples.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Thermal Sciences (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
US12/835,298 2009-07-30 2010-07-13 Cooling apparatus for semiconductor component Abandoned US20110024091A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2009-0069794 2009-07-30
KR1020090069794A KR101031054B1 (ko) 2009-07-30 2009-07-30 반도체 부품용 냉각장치

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021019786A1 (ja) * 2019-08-01 2021-02-04 日本電信電話株式会社 冷却装置
CN112414260A (zh) * 2020-12-01 2021-02-26 中国航发沈阳发动机研究所 一种航空发动机扩散器径向距离测量工装

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070163765A1 (en) * 2003-10-31 2007-07-19 Patrick Rondier Power-electronic-cooling device

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19643717A1 (de) 1996-10-23 1998-04-30 Asea Brown Boveri Flüssigkeits-Kühlvorrichtung für ein Hochleistungshalbleitermodul
JP2001035981A (ja) 1999-07-16 2001-02-09 Toshiba Corp 半導体素子用冷却器及びこれを用いた電力変換装置
JP2005019905A (ja) 2003-06-30 2005-01-20 Matsushita Electric Ind Co Ltd 冷却装置

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070163765A1 (en) * 2003-10-31 2007-07-19 Patrick Rondier Power-electronic-cooling device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021019786A1 (ja) * 2019-08-01 2021-02-04 日本電信電話株式会社 冷却装置
JPWO2021019786A1 (ko) * 2019-08-01 2021-02-04
JP7481635B2 (ja) 2019-08-01 2024-05-13 日本電信電話株式会社 冷却装置
CN112414260A (zh) * 2020-12-01 2021-02-26 中国航发沈阳发动机研究所 一种航空发动机扩散器径向距离测量工装

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KR101031054B1 (ko) 2011-04-25

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