Semiconductor device for radio frequencies of more than 10 GHz and method for producing the device

• US 20070023896A1
• Filed: 07/18/2006
• Published: 02/01/2007
• Est. Priority Date: 07/18/2005
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Theuss, Horst, Pressel, Klaus, Dangelmaier, Jochen
• Granted Patent: US 7,659,618 B2
• Time in Patent Office: Days
• US Class Current: 257/728
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48471 the other connecting portion not on the bonding area being a ball bond, i.e. wedge-to-ball, reverse stitch
• CPC Class Codes: H01L 2224/48479 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85051 Forming additional members, e.g. for "wedge-on-ball", "ball-on-wedge", "ball-on-ball" connections
• CPC Class Codes: H01L 2224/85186 connecting first outside the semiconductor or solid-state body, i.e. off-chip, reverse stitch
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 2224/85986 Specific sequence of steps, e.g. repetition of manufacturing steps, time sequence
• CPC Class Codes: H01L 23/3121 a substrate forming part of the encapsulation
• CPC Class Codes: H01L 23/315 the encapsulation having a cavity
• CPC Class Codes: H01L 23/552 Protection against radiation, e.g. light or electromagnetic waves
• CPC Class Codes: H01L 23/60 Protection against electrostatic charges or discharges, e.g. Faraday shields
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01068 : Erbium [Er]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/16235 : Connecting to a semiconductor or solid-state bodies, i.e. cap-to-chip
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding

Abstract

A semiconductor device for radio frequencies of more than 10 GHz having a semiconductor chip is disclosed. In one embodiment, the semiconductor chip, on its active top side, having a radio-frequency region and a low-frequency region and/or a region which is supplied with DC voltage. In one embodiment, the low-frequency region and/or the region which is supplied with DC voltage of the semiconductor chip is directly embedded in a plastic housing composition, the plastic housing composition is arranged such that it is spaced apart from the radio-frequency region on the active top side of the semiconductor chip.

Claims

1. A semiconductor device for radio frequencies of more than 10 GHz comprising:

a semiconductor chip which, on its active top side, comprises a radio-frequency region and a low-frequency region and/or a region which is supplied with DC voltage, the low-frequency region and/or the region which is supplied with DC voltage of the semiconductor chip being embedded in a plastic housing composition and the plastic housing composition being arranged such that it is spaced apart from the radio-frequency region, by a cavity, on the active top side of the semiconductor chip.

2. The semiconductor device as claimed in claim 1, wherein the radio-frequency region comprises at least one contact area having a bonding wire which is partially arranged in the cavity and is partially arranged in the plastic housing composition.

3. The semiconductor device as claimed in claim 2, wherein the bonding wire is fixed in an adhesive layer between a cover and a wall structure of the cavity, the adhesive layer having a thickness which is greater than or equal to the diameter of the bonding wire.

4. The semiconductor device as claimed in claim 3, wherein the wall structure comprises a photoresist which can be patterned by means of photolithography and can be cured.

5. The semiconductor device as claimed in claim 3, wherein the wall structure is terminated by a cover whose areal extent has been adapted.

6. The semiconductor device as claimed in claim 3, wherein the wall structure and at least parts of the cover are surrounded by the plastic housing composition.

7. The semiconductor device as claimed in claim 5, wherein the top side of the cover is free of plastic housing composition.

8. The semiconductor device as claimed in claim 5, wherein the cover comprises a silicon plate.

9. The semiconductor device as claimed in claim 5, wherein the cover comprises a metal plate.

10. The semiconductor device as claimed in claim 5, wherein the cover comprises a glass plate.

11. The semiconductor device as claimed in claim 5, wherein the cover comprises a ceramic plate.

12. The semiconductor device as claimed in claim 5, wherein the cover comprises a polymeric plastic plate.

13. The semiconductor device as claimed in claim 5, wherein a double-sided adhesive film is arranged between the cover and the wall structure.

14. The semiconductor device as claimed in claim 5, wherein an adhesive layer is arranged between the cover and wall structure.

15. The semiconductor device as claimed in claim 2, wherein the active top side of the semiconductor chip has contact areas outside the wall structure, the contact areas being electrically connected to contact pads on a wiring substrate via bonding wires and being embedded by the plastic housing composition.

16. The semiconductor device as claimed in claim 5, wherein the active top side of the semiconductor chip has contact areas outside and inside the wall structure, the contact areas being electrically connected to contact pads on a wiring substrate via bonding wires.

17. The semiconductor device as claimed in claim 2, wherein the wall structure has a height h of between several hundred nanometers and a few millimeters, where 0.1 μ

m≦

h≦

2000 μ

m.

18. The semiconductor device as claimed in claim 1, wherein the semiconductor device is configured for use in distance radar sensor technology for road and/or rail vehicles and for aircraft in the taxiing traffic and parked traffic on airfields.

19. A method for producing a semiconductor device for radio frequencies of more than 10 GHz, the method comprising:

producing a semiconductor wafer having a multiplicity of semiconductor chips which are arranged in rows and columns and have, on their active top sides, radio-frequency regions and low-frequency regions and/or regions which are supplied with DC voltage;

applying a wall structure which surrounds the radio-frequency regions;

separating the semiconductor wafer into a multiplicity of semiconductor chips;

applying individual semiconductor chips with a wall structure to a carrier having a plurality of semiconductor device positions;

electrically connecting the semiconductor chips to a wiring structure of the carrier via connecting elements;

applying an adapted cover to the wall structure;

packaging the semiconductor chips, the connecting elements, the wall structure and at least parts of the cover and of the carrier in a plastic housing composition; and

separating the semiconductor device positions of the carrier into individual semiconductor devices.

20. The method as claimed in claim 19, comprising applying a wall structure which surrounds the radio-frequency regions using photolithography, the wall structure being formed from a photoresist which has been patterned by photolithography and has been cured.

21. The method as claimed in claim 19, comprising applying a wall structure which surrounds the radio-frequency regions using photolithography, the wall structure being formed from a metal coating which has been patterned by photolithography and has been etched.

22. The method as claimed in claim 19, comprising separating the semiconductor wafer into a multiplicity of semiconductor chips using a sawing technique.

23. The method as claimed in claim 19, comprising separating the semiconductor wafer into a multiplicity of semiconductor chips using laser ablation.

24. The method as claimed in claim 19, comprising applying individual semiconductor chips with a wall structure to a carrier in the semiconductor device positions using an automatic placement machine, the adhesive film from the sawing technique being retained for die bonding.

25. The method as claimed in claim 19, comprising using a bonding wire technique to electrically connect the semiconductor chips to a wiring structure of the carrier via connecting elements.

26. The method as claimed in claim 19, comprising routing the bonding wires via the wall structure, to contact pads of a wiring structure of the carrier in order to electrically connect contact areas inside the radio-frequency region, and the cover is applied to the wall structure, with the bonding wires being partially embedded, using a thick adhesive layer which has been correspondingly matched to the diameter of the bonding wires.

27. The method as claimed in claim 19, comprising using a double-sided adhesive film in order to apply an adapted cover to the wall structure.

28. The method as claimed in claim 19, comprising using a bonding wire technique in order to electrically connect the semiconductor chips to a wiring structure of the carrier via connecting elements.

29. The method as claimed in claim 19, comprising using an injection-molding method or a dispensing method in order to package the semiconductor chips, the connecting elements, the wall structure and at least parts of the cover and of the carrier in a plastic housing composition.

30. The method as claimed in claim 19, comprising using a sawing technique or a laser separating technique in order to separate the semiconductor device positions of the carrier into individual semiconductor devices.

31. A semiconductor device for radio frequencies of more than 10 GHz comprising:

a semiconductor chip which, on its active top side, comprises a radio-frequency region and a low-frequency region and/or a region which is supplied with DC voltage; and

means for providing a plastic housing composition, the low-frequency region and/or the region which is supplied with DC voltage of the semiconductor chip being embedded in the plastic housing composition means and the plastic housing composition means being arranged such that it is spaced apart from the radio-frequency region, by a cavity, on the active top side of the semiconductor chip.