WO1994013012A1 - Device for cooling sheet elements for power electronics - Google Patents

Device for cooling sheet elements for power electronics Download PDF

Info

Publication number
WO1994013012A1
WO1994013012A1 PCT/SE1993/000824 SE9300824W WO9413012A1 WO 1994013012 A1 WO1994013012 A1 WO 1994013012A1 SE 9300824 W SE9300824 W SE 9300824W WO 9413012 A1 WO9413012 A1 WO 9413012A1
Authority
WO
WIPO (PCT)
Prior art keywords
cavity
heat sink
element
power
power electronics
Prior art date
Application number
PCT/SE1993/000824
Other languages
French (fr)
Inventor
Waldemar Belwon
Gösta HESSLOW
Tomas Melberg
Original Assignee
Asea Brown Boveri Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to SE9203533-6 priority Critical
Priority to SE9203533A priority patent/SE9203533L/en
Application filed by Asea Brown Boveri Ab filed Critical Asea Brown Boveri Ab
Publication of WO1994013012A1 publication Critical patent/WO1994013012A1/en

Links

Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00Printed circuits
    • H05K1/02Details
    • H05K1/0277Bendability or stretchability details
    • H05K1/0278Rigid circuit boards or rigid supports of circuit boards locally made bendable, e.g. by removal or replacement of material
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/34Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H01L23/367Cooling facilitated by shape of device
    • H01L23/3675Cooling facilitated by shape of device characterised by the shape of the housing
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L23/00Details of semiconductor or other solid state devices
    • H01L23/34Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/40Mountings or securing means for detachable cooling or heating arrangements ; fixed by friction, plugs or springs
    • H01L23/4093Snap-on arrangements, e.g. clips
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00Constructional details common to different types of electric apparatus
    • H05K7/20Modifications to facilitate cooling, ventilating, or heating
    • H05K7/2089Modifications to facilitate cooling, ventilating, or heating for power electronics, e.g. for inverters for controlling motor
    • H05K7/209Heat transfer by conduction from internal heat source to heat radiating structure
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001Technical content checked by a classifier
    • H01L2924/0002Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00Printed circuits
    • H05K1/02Details
    • H05K1/03Use of materials for the substrate
    • H05K1/0306Inorganic insulating substrates, e.g. ceramic, glass
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/03Conductive materials
    • H05K2201/0332Structure of the conductor
    • H05K2201/0388Other aspects of conductors
    • H05K2201/0394Conductor crossing over a hole in the substrate
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/09Shape and layout
    • H05K2201/09009Substrate related
    • H05K2201/09036Recesses or grooves in insulating substrate
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/09Shape and layout
    • H05K2201/09009Substrate related
    • H05K2201/0909Preformed cutting or breaking line
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/30Details of processes not otherwise provided for in H05K2203/01 - H05K2203/17
    • H05K2203/302Bending a rigid substrate; Breaking rigid substrates by bending
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/0058Laminating printed circuit boards onto other substrates, e.g. metallic substrates
    • H05K3/0067Laminating printed circuit boards onto other substrates, e.g. metallic substrates onto an inorganic, non-metallic substrate

Abstract

The invention relates to a device for cooling sheet elements (20) for power electronics, comprising a heat sink (10) provided with cooling fins (14). Said heat sink delimiting an enclosed cavity (12), against the interior wall (32) of which a power electronics element (20) is intended to be fixed. The heat sink (10) is hermetically sealable.

Description

Device for cooling sheet elements for power electronics

The present invention relates to an invention for sheet elements for power electronics, such as power semiconductors or power semiconductors mounted on substrates, said device comprising a heat sink provided with cooling fins and being composed of a material with good thermoconductivity and on which the power electronics elements are intended to be mounted in a heat transferring manner.

Heat generating semiconductors require in most applications some form of cooler to maintain the operating temperature at an acceptably low level. Usually separate encapsuled power semiconductors are mounted on one or more finned cooling elements, which are in turn mounted on circuit boards. Alter¬ natively, power semiconductors are first mounted as naked chips on a substrate, which is in turn mounted in a protec¬ tive plastic casing. In order to protect these chips and any associated control electronics elements from dirt and oxida¬ tion, the space in the casing is partially filled with a silicone gel, for example. The rest of the space is filled out with an epoxy mixture. Such a semiconductor construction is usually called a "power module". The plastic casing of the power module is usually fixed with screws or adhesive on the outside of a cooling element. In order to achieve even mount¬ ing force of the semiconductor against the cooler when using screws, spring washers must be employed, which when mounted must be carefully compressed so that they can move as the temperature changes.

A general purpose of the present invention is to achieve improved cooling of power electronics elements at the same time as they can be protected in a better and simpler manner against chemical and mechanical damage.

In its broadest aspect, this is achieved in principle accord- ing to the invention by virtue of the fact that the required encapsuling of the power electronics element is effected by the cooling element itself, which simultaneously has the function of a very effective cooler and a capsule for the power electronics element. The heat sink itself is thus made to delimit an enclosed cavity, which has at least one wall side on which at least one sheet element for power electro¬ nics is intended to be fixed, said heat sink having at least one opening through which the power electronics element can be inserted into the cavity and which can be sealed by means of a cover.

According to a preferred embodiment of the invention, the heat sink is made of an extruded hollow profile with cooling fins, both ends of said profile being sealable by means of respective covers. This provides a heat sink with a large cooling surface by virtue of the fact that its external surfaces have cooling fins to the greatest possible extent in order to effectively dissipate heat from the power electro¬ nics element(s) mounted against an interior cavity wall in the heat sink.

Suitably the cover or covers are provided with means for clamping the sheet element for power electronics against the interior side wall of the hollow profile, especially of the type described in more detail in our copending patent appli¬ cation SE-A-9203532-8 with the title "Means for fixing elec¬ tronics elements in sheet form", said cover simultaneously hermetically sealing the cavity and clamping the sheet ele¬ ment for power electronics against a cavity wall in the heat sink.

According to another aspect of the device according to the invention the heat sink is provided with an entry hole commu¬ nicating with the cavity and in which a connector is disposed to be fixed, said connector having contact elements for power connection to corresponding contact elements on a connector element associated with the power electronics element, said connector being coordinated with a seal for hermitically sealing the entry hole. This provides power supply to the electronics element inside the heat sink at the same time as the cavity is sealed so that it can enclose diffusion-tight a protective and/or cooling medium for the electronics compo¬ nents therein.

Further advantages and features of the invention will be described in more detail below with reference to the accom¬ panying drawing, in which

Figure 1 is a schematic cross-sectional view of a heat sink in the form of a hollow profile with a sheet element for power electronics mounted therein with associa¬ ted coupling elements and a signal electronics unit, and

Figure 2 is a sectional view along the line A-A in Figure 1 but with the coupling and signal electronics ele¬ ments omitted.

In Figure 1 the numeral 10 designates a heat sink in the form of an extruded hollow profile, preferably of aluminum, with essentially rectangular cross-sectional shape. The profile 10 has an inner cavity 12, and three of its four sides provided with cooling fins 14. The upper side 16 of the hollow profile in Figure 1 is a mounting flange for mounting the heat sink

10 on a supporting component. The heat sink 10 is intended to hermitacally enclose an electronics unit 18, which in the example shown consists of a power semiconductor element 20 mounted on a sheet substrate, a connecting plate 22 with contact elements 24 and a control or signal electronics unit 26 with a contact element 28 and legs 30 connecting the control electronics unit 26 with the power semiconductor 20.

The sheet power electronics element 20 is designed to be clamped with even force against the wall 32 of the cavity 12, so that heat generated in the power semiconductor element 20 can be effectively drained off to the heat sink 10 and its cooling fins 14. In order to achieve a protective hermetic encapsuling of the entire electronics unit 18 in the cavity 12 in the heat sink 10, the end openings of the cavity 12 can be sealed by means of end covers 34 (Fig 2) . The end covers 34 are suitably made in a manner which is described in more detail in our copending SE-A 9203532-8 and each cover has the double function of simultaneously clamping the semiconductor element 20 with even force against the wall 32 of the cavity and hermetically sealing the respective end opening of the cavity 12 by means of seals 36 on the periphery of the cover 34. The cover 34 has for this purpose two spring clamp ele- ments 38 with an external ridge 40, which when inserted into the cavity 12 (as shown at the top of Fig 2) slides against the wall 32 of the cavity and bends the clamping elements 38 inwards, whereupon a gripping portion 42 on the end of the clamping element is lifted far enough from the wall of the cavity that it passes without touching over the edge portion of a sheet semiconductor element 20 placed against the wall 32 of the cavity. The ridge 40 on the clamping element 38 is designed to snap into a cavity 44 in the wall 32 of the cavity, whereupon the gripping portion 42 presses firmly and with even force against the power semiconductor element 20 or its substrate, at the same time as the seal 36 is compressed at the opening of the cavity to hermetically seal the same, as is shown at the bottom of Figure 2.

In order to facilitate insertion of the power electronics element 20 and its coupling plate 22 through one opening in the cavity 12 prior to insertion of the cover 34, the cavity 12 can be provided with grooves or shoulders 46,48.

The heat sink 10 also has an opening 50 in its mounting flange side 16 for a connector 52 of insulating material, which has soldered-in contact pins 54 and 56 for power con¬ nection with the corresponding contact elements 24 of the coupling plate 22 and the contact elements 28 of the control electronics unit 26. The connector 52 has a peripheral seal 58 for sealing against a shoulder 60. A lock ring 62 is arranged to be inserted in a groove 64 to fix the connector 52 in the heat sink 10 with the seal 58 comoressed. The coupling plate 22 is made as a circuit board which is somewhat movably mounted relative to the rigidly fixed semi¬ conductor element 20 and is joined thereto via flexible con¬ ductors 66. Although not shown in the drawing, it can be suitable - especially where the power electronics element 20 is mounted on a supporting substrate - that this substrate and the coupling plate 22 be made from a common flat sheet element, which after being cut up is divided into separate components, connected to each other resiliently and movably via the conductor pattern, corresponding to the conductors 66 in Fig 1. The flexible conductors 66 allow the coupling plate 22 to move somewhat in its own plane and axially during in¬ sertion of the connector 52 into its opening 50, when the contact pins 54 are centered in their associated contact ele- ments 24 without this affecting the position of the fixed power semiconductor element 20. Furthermore, thermal material movements in the various electronics components can be ab¬ sorbed by this flexible mounting of the coupling plate. The contact pins 56 extend freely through the holes in the coup- ling plate 22 into contact with the corresponding contact elements 28 of the control electronics unit 26.

The mounting of an electronics unit 18 in a heat sink 10 serving at the same time as a casing is done in the following manner:

A pretested and assembled electronics unit 18, consisting of the power semiconductor element 20 mounted on a substrate, the coupling plate 22 and the control electronics unit 26, is inserted into the cavity 12 through one end opening to its intended place, where the substrate is in contact with one of the walls 32 of the cavity. Then the connector 52 is inserted into its opening 50, and the unit 20,22,26 is correctly posi¬ tioned in the cavity 12 with the aid of the contact pins 54,56. The two end covers 34 with their clamping elements 38 can be inserted into the cavity 12 at either end thereof to seal the cavity 12 by means of seals 36 and at the same time clamp the substrate with its power semiconductor element 20 against the cavity wall 32 with the aid of the gripping portions 42. If the cavity 12 is to be filled with a cooling liquid, which also protects the semiconductor chips against any aggressive substances, the connector 52 is removed and the cavity 12 is then filled with said liquid through the opening 50. Finally, the connector 52 is remounted. In order to absorb changes in volume in the cooling medium depending on changes in temperature, a pressure equalizing elastic element 68 can be mounted between the clamping elements 38 of the end covers 34.

The invention provides a cooling device and a sheet power electronics element especially suited thereto, and this provides i.a. the following advantages:

a) Improved cooling and improved protection for the semicon¬ ductor chips by virtue of the fact that they are mounted internally in firm surface contact with a cavity wall in a heat sink means made as an enclosed casing, which can be made diffusion-tight in order to make possible use of a cooling liquid. By virtue of the fact that the heat sink surrounds the semiconductor chips, a large cooling surface is obtained.

b) Simplified mounting process by virtue of the fact that no screws or adhesives are required to fix the semiconductors to the cooling surface.

c) Improved protection against electrostatic discharges and improved electromagnetic compatibility by virtue of the fact that the cooling device surrounds the electronics unit.

Claims

Claims
1. Device for cooling sheet power electronics elements, such as power semiconductors or power semiconductors mounted on a substrate, comprising a heat sink (10) provided with cooling fins (14) and being composed of a material with good thermal conductivity and on which the power electronics elements (20) are intended to be mounted in a heat transferring manner, c h a r a c t e r i z e d in that the heat sink (10) itself is made to delimit a closed cavity (12) , which has at least one wall side (32) , on which at least one sheet power elec- tronics element (20) is intended to be fixed, said heat sink (10) having at least one opening through which the power electronics element (20) can be inserted into the cavity (12) and which can be sealed by means of a cover (34) .
2. Device according to Claim 1, c h a r a c t e r i z e d in that the heat sink (10) is formed of an extruded hollow profile with cooling fins, both ends of said profile being sealable by means of respective covers (34) .
3. Device according to Claim l or 2, c h a r a c t e r ¬ i z e d in that each cover (34) has a sealing means (36) for hermetically sealing the cavity (12) .
4. Device according to one of Claims 1 - 3, c h a r a c t - e r i z e d in that the cover or covers (34) is/are provided with means (38,42) for clamping the sheet power electronics element (20) against the internal side wall (32) of the hollow profile.
5. Device according to one of Claims 1 - 4, c h a r a c t ¬ e r i z e d in that the heat sink (10) is provided with an entry hole (50) communicating with the cavity and in which a connector (52) is disposed to be fixed, said connector (52) having contact elements (54) for power connection to corre- sponding contact elements (24) on a coupling element (22) associated with the power electronics element (20) .
6. Device according to Claim 5, c h a r a c t e r i z e d in that a shoulder (48) for the coupling element (22) is made in the cavity (12) to limit the movement of the coupling element (22) inwards therein when the contact elements (54) of the connector (52) are brought into engagement with the contact elements (24) of the coupling element.
7. Device according to Claim 5 or 6, c h a r a c t e r ¬ i z e d in that a seal (58) for hermetic sealing of the entry hole (50) is coordinated with the connector (52) .
PCT/SE1993/000824 1992-11-24 1993-10-11 Device for cooling sheet elements for power electronics WO1994013012A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
SE9203533-6 1992-11-24
SE9203533A SE9203533L (en) 1992-11-24 1992-11-24 Apparatus for cooling the power electronics board-shaped elements together with disc shaped power elements to be installed in such a cooling device

Publications (1)

Publication Number Publication Date
WO1994013012A1 true WO1994013012A1 (en) 1994-06-09

Family

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Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/SE1993/000824 WO1994013012A1 (en) 1992-11-24 1993-10-11 Device for cooling sheet elements for power electronics
PCT/SE1993/001004 WO1994013014A1 (en) 1992-11-24 1993-11-22 Disc-formed, heat producing electronic element

Family Applications After (1)

Application Number Title Priority Date Filing Date
PCT/SE1993/001004 WO1994013014A1 (en) 1992-11-24 1993-11-22 Disc-formed, heat producing electronic element

Country Status (2)

Country Link
SE (1) SE9203533L (en)
WO (2) WO1994013012A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000074137A1 (en) * 1999-05-31 2000-12-07 Siemens Aktiengesellschaft Device for cooling semiconductor components

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005053396B4 (en) * 2005-11-09 2010-04-15 Semikron Elektronik Gmbh & Co. Kg Circuit device, in particular frequency

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB832067A (en) * 1955-05-10 1960-04-06 Westinghouse Electric Corp Improvements in or relating to semiconductor devices
GB921251A (en) * 1960-03-07 1963-03-20 Pacific Semiconductors Inc Semiconductor mounting
US5132875A (en) * 1990-10-29 1992-07-21 Compaq Computer Corporation Removable protective heat sink for electronic components

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4246597A (en) * 1979-06-29 1981-01-20 International Business Machines Corporation Air cooled multi-chip module having a heat conductive piston spring loaded against the chips
US4479140A (en) * 1982-06-28 1984-10-23 International Business Machines Corporation Thermal conduction element for conducting heat from semiconductor devices to a cold plate
JPH063831B2 (en) * 1987-04-08 1994-01-12 株式会社日立製作所 Cooling device and a semiconductor device using the same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB832067A (en) * 1955-05-10 1960-04-06 Westinghouse Electric Corp Improvements in or relating to semiconductor devices
GB921251A (en) * 1960-03-07 1963-03-20 Pacific Semiconductors Inc Semiconductor mounting
US5132875A (en) * 1990-10-29 1992-07-21 Compaq Computer Corporation Removable protective heat sink for electronic components

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000074137A1 (en) * 1999-05-31 2000-12-07 Siemens Aktiengesellschaft Device for cooling semiconductor components

Also Published As

Publication number Publication date
SE9203533L (en) 1994-05-24
WO1994013014A1 (en) 1994-06-09
SE9203533D0 (en) 1992-11-24
SE500281C2 (en) 1994-05-24

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