US-12622196-B2 - Wafer, electronic component and method using laser penetration affecting structure

Abstract

A wafer, electronic component and method are disclosed. In one example, the wafer comprises an array of a plurality of electronic components. The separation frame separating neighboured electronic components, wherein the separation frame comprises a laser penetration affecting structure configured for locally affecting laser penetration when subjecting the separation frame to laser processing during stealth dicing.

Inventors

• Gunther Mackh
• Adolf Koller
• Michael Kraus

Assignees

• INFINEON TECHNOLOGIES AG

Dates

Publication Date

20260505

Application Date

20220811

Priority Date

20210825

Claims (17)

1. 1 . A wafer, which comprises: a front side and an opposing back side; an array of a plurality of electronic components; and a separation frame separating neighboured electronic components; wherein the separation frame comprises a laser penetration affecting structure configured for locally affecting laser penetration into the wafer from the front side when subjecting the separation frame to laser processing during stealth dicing, and wherein the laser penetration affecting structure comprises plurality of non-electrical substructures spaced apart from one another in a periodic pattern at only the front side.
2. 2 . The wafer according to claim 1 , wherein the laser penetration affecting structure is a defect density suppression structure for suppressing formation of defects during separating the electronic components from the wafer.
3. 3 . The wafer according to claim 1 , wherein the laser penetration affecting structure is a breaking strength enhancement structure for enhancing a breaking strength during separating the electronic components from the wafer.
4. 4 . The wafer according to claim 1 , wherein the laser penetration affecting structure comprises a pattern configured for trimming a laser beam during stealth dicing.
5. 5 . The wafer according to claim 1 , wherein the laser penetration affecting structure is configured for locally blocking a laser beam when irradiated onto the separation frame.
6. 6 . The wafer according to claim 1 , comprising at least one of the following features: wherein the laser penetration affecting structure comprises a metallic structure for reflecting a laser beam; wherein the laser penetration affecting structure comprises a locally highly doped region for absorbing a laser beam; wherein the laser penetration affecting structure comprises a dielectric material having a different dielectric constant compared to surrounding material and being configured to manipulate a focus position, in particular a focus depth, of the laser beam; wherein the laser penetration affecting structure has a locally increased surface roughness compared to surrounding material to thereby defocus a laser beam.
7. 7 . The wafer according to claim 1 , wherein the laser penetration affecting structure is configured for affecting laser penetration differently in different depth levels inside of the separation frame.
8. 8 . The wafer according to claim 1 , wherein the laser penetration affecting structure comprises a pattern of substructures located along one or more straight separation lines of the separation frame.
9. 9 . The wafer according to claim 8 , comprising at least one of the following features: wherein the pattern is a regular, in particular periodic, pattern of substructures; wherein the pattern is absent in crossing regions of the separation frame; wherein the substructures comprise a plurality of stripe pairs, each stripe pair have having a spacing between its stripes, wherein in particular different ones of the stripe pairs are spaced along a respective one of the one or more straight separation lines.
10. 10 . An electronic component, which comprises: a semiconductor body having an upper major surface and a lower major surface; an active region in and/or on a central portion of the semiconductor body; and a separation frame structure in an edge region of the semiconductor body; wherein the separation frame structure comprises a laser penetration affecting structure separate from the active region configured for locally affecting laser penetration during subjecting the separation frame structure to laser processing during stealth dicing, and wherein the laser penetration affecting structure comprises a plurality of non-electrical substructures spaced apart from one another in a periodic pattern at only the upper major surface.
11. 11 . The electronic component according to claim 10 , wherein the electronic component is configured as microelectromechanical system.
12. 12 . The electronic component according to claim 10 , wherein the laser penetration affecting structure is arranged along at least part of each of surrounding edges of the semiconductor body.
13. 13 . The electronic component according to claim 10 , wherein the laser penetration affecting structure is absent in each of corner regions of the semiconductor body.
14. 14 . The electronic component according to claim 10 , wherein the laser penetration affecting structure is a defect density suppression structure for suppressing formation of defects during separating the electronic component from a wafer.
15. 15 . The electronic component according to claim 14 , wherein a thickness of the semiconductor body is in a range from 300 μm to 1 mm.
16. 16 . The electronic component according to claim 10 , wherein the laser penetration affecting structure is a breaking strength enhancement structure for enhancing a breaking strength during separating the electronic component from a wafer.
17. 17 . The electronic component according to claim 16 , wherein a thickness of the semiconductor body is in a range from 100 μm to 300 μm.

Description

CROSS-REFERENCE TO RELATED APPLICATION This Utility Patent Application claims priority to German Patent Application No. 10 2021 121 994.9, filed Aug. 25, 2021, which is incorporated herein by reference. BACKGROUND OF THE INVENTION The present invention relates to a wafer, an electronic component, and a method of separating electronic components from a wafer. Packages may be denoted as for example encapsulated electronic chips with electrical connects and being mounted to an electronic periphery, for instance on a printed circuit board. Before packaging, a semiconductor wafer is singularized into a plurality of electronic chips. After singularizing the wafer into the singularized electronic chips, the electronic chips of the wafer may be subsequently used for further processing. Singularization may be accomplished by mechanically or laser cutting the wafer. However, separated electronic components may be damaged during separation. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of exemplary embodiments of the invention and constitute a part of the specification, illustrate exemplary embodiments of the invention. In the drawings: FIG. 1 shows a plan view of a wafer according to an exemplary embodiment. FIG. 2 shows a plan view of an electronic component according to an exemplary embodiment. FIG. 3 shows a flowchart of a method of separating electronic components from a wafer according to an exemplary embodiment. FIG. 4 shows a plan view of a wafer according to an exemplary embodiment. FIG. 5 shows a cross-sectional view of a wafer comprising electronic components to be separated according to an exemplary embodiment. FIG. 6 shows a plan view of a wafer according to an exemplary embodiment. FIG. 7 shows a cross-sectional view of a wafer according to an exemplary embodiment. DETAILED DESCRIPTION There may be a need to separate electronic components from a wafer with low risk of damage. According to an exemplary embodiment, a wafer is provided which comprises an array of a plurality of electronic components, and a separation frame separating neighboured electronic components, wherein the separation frame comprises a laser penetration affecting structure configured for locally affecting laser penetration when subjecting the separation frame to laser processing during stealth dicing. According to another exemplary embodiment, an electronic component is provided which comprises a semiconductor body, an active region in and/or on a central portion of the semiconductor body, and a separation frame structure in an edge region of the semiconductor body, wherein the separation frame structure comprises a laser penetration affecting structure configured for locally affecting laser penetration during subjecting the separation frame structure to laser processing during stealth dicing. According to still another exemplary embodiment, a method of separating electronic components from a wafer is provided, wherein the method comprises providing the wafer with a separation frame separating neighboured electronic components, providing the separation frame with a laser penetration affecting structure, and subjecting the laser penetration affecting structure to laser processing during stealth dicing along the separation frame for locally affecting laser penetration. According to an exemplary embodiment, separation of a wafer into individual electronic components, which are previously integrally connected in the wafer compound and spaced by a separation frame, may be carried out with a reduced risk of damage thanks to the implementation of a dedicated laser penetration affecting structure formed in the separation frame. During stealth dicing, a wafer may be separated into electronic components by firstly mechanically weakening the separation frame by laser processing and by subsequently disrupting the laser-weakened separation frame for obtaining individual electronic components. By integrating said laser penetration affecting structure as a hardware feature in the separation frame, laser processing in terms of stealth dicing may be controlled more precisely by affecting the laser beam in the region of the laser penetration affecting structure in a controlled and different way as compared to a region of the separation frame apart from the laser penetration affecting structure. Preferably but not necessarily, the laser penetration affecting structure may locally weaken the impact of the laser beam on the material of the separation frame. Hence, by structurally adjusting the separation frame for controlling laser impact in accordance with a design of the laser penetration affecting structure, undesired phenomena and thus damage of the wafer and/or its separated electronic components may be reliably prevented. This may improve the yield at a high throughput. Furthermore, due to the structural implementation of the laser penetration affecting structure and the separation