Spring element for a power semiconductor module

Abstract

The present invention relates to a spring element for a power semiconductor module, wherein the spring element includes a first part made from a first material and a second part made from a second material, the first material being different from the second material, wherein the first part comprises both a first contact portion having a first contact and a second contact portion having a second contact, wherein the first part comprises an electrically conductive path formed from the first contact portion to the second contact portion, and wherein the second part is adapted for exerting a spring force (FS) onto the first contact portion and the second contact portion for pressing the first contact to a first contact area of a power semiconductor module and the second contact to a second contact area of a power semiconductor module. Such a spring element may form a press contact in a power semiconductor module and may be less bulky compared to solutions in the prior art and may be formed cost-sparingly.

Claims

1. A spring element for a power semiconductor module, comprising: a first part made from a first material and a second part made from a second material, the first material being different from the second material, wherein the first part comprises both a first contact portion having a first contact and a second contact portion having a second contact, wherein the first part comprises an electrically conductive path formed from the first contact portion to the second contact portion, and wherein the second part is adapted for exerting a spring force onto the first contact portion and the second contact portion for pressing the first contact to a first contact area of a power semiconductor module and the second contact to a second contact area of a power semiconductor module, wherein the second part comprises a first press portion, a second press portion, and a deformation portion for providing a spring force to the first press portion and the second press portion, wherein the first press portion is located opposite to the second press portion with regard to the deformation portion, wherein the first contact portion is located in vicinity to the first press portion and the second contact portion is located in vicinity to the second press portion such, that the spring force exerted by the deformation portion presses the first press portion against the first contact portion and the second press portion against the second contact portion, wherein at least one of the first press portion, the second press portion, the first contact portion and the second contact portion at least partly proceed perpendicular to the direction at which the spring force acts on the first contact portion and the second contact portion, wherein the first press portion is at least partly enframed by the first contact portion and the second press portion is at least partly enframed by the second contact portion in the direction of the spring force at the respective contact portion as well as in the opposite direction and additionally in at least two opposite directions being perpendicular to the spring force, wherein the first part forms a first bracket and wherein the second part forms a second bracket, wherein the first part is fixated to the second part by at least one form-locked connection, wherein the spring element consists of the first part and the second part, and wherein the first part and the second part each are formed as one-piece parts.

2. The spring element according to claim 1, wherein the first material has an electric conductivity of equal or more than 2.010.sup.7 S/m.

3. The spring element according to claim 1, wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa.

4. The spring element according to claim 1, wherein the first material is selected from the group consisting of copper, silver and aluminum.

5. The spring element according to claim 1, wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

6. A power semiconductor module, comprising at least one spring element according to claim 1.

7. The power semiconductor module according to claim 6, wherein the spring element forms part of a control path for controlling the power semiconductor module.

8. The spring element according to claim 2, wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa.

9. The spring element according to claim 2, wherein the first material is selected from the group consisting of copper, silver and aluminum.

10. The spring element according to claim 3, wherein the first material is selected from the group consisting of copper, silver and aluminum.

11. The spring element according to claim 2, wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

12. The spring element according to claim 3, wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

13. The spring element according to claim 4, wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

14. The spring element according to claim 1, wherein the first material has an electric conductivity of equal or more than 2.010.sup.7 S/m; wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa; wherein the first material is selected from the group consisting of copper, silver and aluminium; and wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

15. The spring element according to claim 6, wherein the first material has an electric conductivity of equal or more than 2.010.sup.7 S/m; and wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa.

16. The power semiconductor module according to claim 6, wherein the first material of spring element has an electric conductivity of equal or more than 2.010.sup.7 S/m.

17. The power semiconductor module according to claim 6, wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa.

18. The power semiconductor module according to claim 6, wherein the first material has an electric conductivity of equal or more than 2.010.sup.7 S/m; wherein the second material has a spring force being determined by the young modulus of equal or more than 100 GPa; wherein the first material is selected from the group consisting of copper, silver and aluminium; and wherein the second material is selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Additional features, characteristics and advantages of the subject-matter of the invention are disclosed in the subclaims, the figures and the following description of the respective figures and example, whichin an exemplary fashionshow an embodiment and example of a spring element according to the invention.

(2) In the figures:

(3) FIG. 1 shows an embodiment of a spring element according to the invention; and

(4) FIG. 2 shows the spring element according to FIG. 1 in a power semiconductor module.

DETAILED DESCRIPTION OF THE INVENTION

(5) FIG. 1 shows an embodiment of a spring element 10 according to the invention and FIG. 2 shows the respective spring element 10 in a power semiconductor module. The spring element 10 is particularly suitable for mounting it into a power semiconductor module and especially for forming a press contact in a control path of the power semiconductor module.

(6) The spring element 10 comprises a first part 12 made from a first material and a second part 14 made from a second material, the first material being different from the second material. In detail the first material may be selected from the group consisting of copper, silver and aluminum, and/or the second material may be selected from the group consisting of steel, steel alloys, copper alloys, bronze alloys, or nickel-alloys. For example, the first part 12 may be formed from copper and the second part 14 may be formed from steel.

(7) It can further be seen that the spring element 10 consists of the first part 12 and the second part 14, wherein both the first part 12 and the second part 14 are formed as one-piece parts and are further formed as brackets. Therefore, no further parts are required.

(8) The first part 12 comprises both a first contact portion 26 having a first contact 16 and a second contact portion 28 having a second contact 18, wherein the first part 12 comprises an electrically conductive path formed from the first contact portion 26 to the second contact portion 28.

(9) The second part 14 is adapted for exerting a spring force F.sub.S onto the first contact portion 26 and the second contact portion 28 for pressing the first contact 16 to a first contact area 30 and the second contact 18 to a second contact area 32. The first contact area 30 may be part of a top plate and the second contact area 32 may be part of a gate contact, or ground plate, for example.

(10) In detail it is provided that the second part 14 comprises a first press portion 20, a second press portion 22, and a deformation portion 24 for providing a spring force F.sub.S to the first press portion 20 and the second press portion 22, wherein the first press portion 20 is located opposite to the second press portion 22 with regard to the deformation portion 24. The first contact portion 26 is further located in vicinity to the first press portion 20 and the second contact portion 28 is located in vicinity to the second press portion 22 such, that the spring force F.sub.S exerted by the deformation portion 24 presses the first press portion 20 against the first contact portion 26 and the second press portion 22 against the second contact portion 28 and thus the latter to the contact areas 30, 32, respectively.

(11) It may further be seen that the first press portion 20, the second press portion 22, the first contact portion 26 and the second contact portion 28 at least partly proceed essentially perpendicular to the direction at which the spring force F.sub.S acts on the first contact portion 26 and the second contact portion 28.

(12) It can further be seen that both the contact portions 26, 28 and the press portions 20, 22 have an essentially oval form and preferably touching each other proceeding that oval form. The oval form comprises the contacts 16, 18 forming a straight portion of the oval form essentially perpendicular to the spring force F.sub.S and two semi-circular sections 17, 19 provided subsequent and thus adjacent to the straight portions. The oval form is respectively opened by an opening 21, 23 in a direction towards the deformation portion 14 in order to let the second part 14 proceed through that opening.

(13) This allows that an enframing of the press portions 20, 22 of the second part 14 with the contact portions 26, 28 of the first part 12 may be realized in the direction of the spring force F.sub.S at the respective contact portion 26, 28 as well as in the opposite direction and additionally in at least two opposite directions being essentially perpendicular to the spring force F.sub.S.

(14) While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to be disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting scope.

REFERENCE SIGNS LIST

(15) 10 spring element 12 first part 14 second part 16 first contact 17 semi-circular portion 18 second contact 19 semi-circular portion 20 first press portion 21 opening 22 second press portion 23 opening 24 deformation portion 26 first contact portion 28 second contact portion 30 first contact area 32 second contact area F.sub.S spring force