METHOD FOR DIVIDING A COMPOSITE INTO SEMICONDUCTOR CHIPS, AND SEMICONDUCTOR CHIP

• US 20180117706A1
• Filed: 12/18/2017
• Published: 05/03/2018
• Est. Priority Date: 08/08/2013
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: KAEMPF, Mathias
• Granted Patent: US 10,232,471 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: B23K 2103/56 semiconducting semiconducting devices B23K2101/40
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: B23K 26/53 for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks
• CPC Class Codes: H01L 21/268 using electromagnetic radiation, e.g. laser radiation
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 21/78 with subsequent division of the substrate into plural individual devices cutting to change the surface-physical characteristics or shape of semiconductor bodies H01L21/304
• CPC Class Codes: H01L 2221/68327 used during dicing or grinding
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination

Abstract

The invention relates to a method for dividing a composite into a plurality of semiconductor chips along a dividing pattern. A composite, which comprises a substrate, a semiconductor layer sequence, and a functional layer, is provided. Separating trenches are formed in the substrate along the dividing pattern. The functional layer is cut through along the dividing pattern by means of coherent radiation. Each divided semiconductor chip has part of the semiconductor layer sequence, part of the substrate, and part of the functional layer. The invention further relates to a semiconductor chip.

Claims

1. Method for dividing a composite into a plurality of semiconductor chips along a dividing pattern, comprising the following steps:

a) providing a composite which has a carrier, a semiconductor layer sequence and a functional layer;

b) forming separating trenches in the carrier along the dividing pattern; and

c) cutting through the functional layer by means of coherent radiation along the dividing pattern;

wherein the divided semiconductor chips each have a part of the semiconductor layer sequence, of the carrier and of the functional layer.

2. Method according to claim 1,

wherein step c) is carried out before step b).

3. Method according to claim 1,

wherein the semiconductor layer sequence is divided into a plurality of semiconductor bodies by means of mesa trenches prior to step c).

4. Method according to claim 3,

wherein the functional layer is cut through in step c) along the mesa trenches.

5. Method according to claim 1,

wherein the semiconductor layer sequence is divided into a plurality of semiconductor bodies by means of mesa trenches, the semiconductor layer sequence and the functional layer being cut through in a common production step in step c).

6. Method according to claim 1,

wherein the coherent radiation in step c) is laser radiation with a pulse duration in the nanosecond or picosecond range.

7. Method according to claim 6,

wherein the laser radiation comprises mutually successive sub-pulses within the pulse duration.

8. Method according to claim 1,

wherein the functional layer comprises a metallic layer and/or a dielectric layer and

wherein the carrier contains a semiconductor material.

9. Method according to claim 1,

wherein the functional layer is disposed between the semiconductor layer sequence and the carrier.

10. Method according to claim 1,

wherein the functional layer extends over the whole surface of the composite before step c).

11. Method according to claim 1, wherein the separating trenches are formed by means of a chemical method.

12. Method according to claim 1, wherein the separating trenches extend completely through the carrier after step b).

13. Method according to claim 1,

wherein in step c), the coherent radiation is radiated onto the functional layer through the separating trenches.

14. Method according to claim 1, wherein the composite has a further functional layer which is cut through by means of coherent radiation along the dividing pattern in step d), and wherein step b) is carried out between step c) and step d).

15. Method according to claim 1, wherein the composite is attached to an auxiliary carrier before division and the semiconductor chips are present on the auxiliary carrier in a geometric arrangement after division.

16. Method according to claim 1, wherein, in step c), the functional layer is cut through only in places along the dividing pattern so that at least one region of the composite has a plurality of contiguous semiconductor chips after step b) and step c).

17. Semiconductor chip having a semiconductor body, a carrier body and a functional layer which are disposed one on another in a vertical direction, wherein, on at least one side surface of the semiconductor chip, the functional layer has traces of a material removal by coherent radiation.

18. Semiconductor chip according to claim 17,

in which the functional layer is disposed between the carrier body and the semiconductor body.

19. Semiconductor chip according to claim 18,

in which a further functional layer is disposed on a side of the carrier body facing away from the semiconductor body, wherein, on at least one side surface of the semiconductor chip, the further functional layer has traces of a material removal by coherent radiation.