Method for processing identification part of wafer and method for preparing wafer

Abstract

The application provides a wafer marking part processing method and a wafer preparation method. The wafer marking part processing method comprises the following steps: S100, bonding a wafer to a glass carrier plate; S200, performing laser modification on a preset part of the wafer by using a hidden laser process to form a modified area, wherein the modified area corresponds to the marking part; S300, at least reserving the bonding connection between the modified area and the glass carrier plate, and performing debonding on the remaining part of the wafer and the glass carrier plate; and S400, separating the wafer and the glass carrier plate, so that the modified area part of the wafer is retained on the glass carrier plate, to form the marking part on the wafer. The prepared wafer marking part has a small volume and does not cause waste of the effective utilization area of the wafer. Moreover, the small marking part does not affect the stability in the subsequent wafer processing process, is beneficial to the uniformity of the preparation of a subsequent wafer electroplating layer, a deposition layer and the like, and thus the quality of the wafer is improved. Moreover, the process is simple and reliable.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device fabrication technology, and in particular to a method for processing marking areas on a wafer and a method for fabricating a wafer. Background Technology

[0002] The wafer fabrication process involves the fabrication of front-side components, a complex and intricate process. To facilitate wafer fabrication, positioning markers must be applied to the wafers.

[0003] In related technologies, a portion of the wafer is directly cut off to form a straight-edged marking area. This approach wastes valuable wafer area and, during processing, can easily cause wafer instability, affecting the uniformity of processes such as electroplating and ultimately impacting wafer quality. Summary of the Invention

[0004] The technical problem to be solved by the present invention is how to prepare reasonable marking areas on wafers. The present invention proposes a method for processing marking areas on wafers and a method for preparing wafers.

[0005] A method for processing the marking portion of a wafer according to an embodiment of the present invention includes:

[0006] S100, bonding the wafer to the glass substrate;

[0007] S200, using stealth laser technology to laser-modify a predetermined area of ​​the wafer to form a modified area, the modified area corresponding to the marked area;

[0008] S300, at least the bonding connection between the modified region and the glass substrate is preserved, and the remaining parts between the wafer and the glass substrate are debonded;

[0009] S400, the wafer and the glass substrate are separated, and the modified region of the wafer is retained on the glass substrate to form a marking region on the wafer.

[0010] According to some embodiments of the present invention, in step S100, an adhesive is used to bond the wafer and the glass substrate.

[0011] In some embodiments of the present invention, in step S200, a stealth laser process is performed from the side of the wafer.

[0012] According to some embodiments of the present invention, the modified region is formed from the outside to the inside of the side of the wafer by adjusting the operating parameters of the stealth laser process.

[0013] In some embodiments of the present invention, in step S300, the area of ​​the retained bonding connection sites is larger than the projected area of ​​the modified region.

[0014] According to some embodiments of the present invention, in step S400, the wafer is vacuum adsorbed using a graphite carrier plate with adsorption pores, thereby separating the wafer from the glass carrier plate.

[0015] In some embodiments of the present invention, before laser modification of a predetermined portion of the wafer using stealth laser technology, the method further includes: grinding the wafer to a predetermined thickness range.

[0016] According to some embodiments of the present invention, the preset thickness range of the wafer is 100 to 300 μm.

[0017] In some embodiments of the present invention, the wafer is a SiC wafer.

[0018] A method for fabricating a wafer with an identification portion according to an embodiment of the present invention includes:

[0019] A100, the wafer marking portion is prepared using the wafer marking portion processing method described above;

[0020] A200, under the marking function of the marking area, performs the fabrication process of the front and back devices of the wafer.

[0021] The present invention has the following beneficial effects:

[0022] The marking area on the wafer prepared by this invention is small, thus avoiding waste of the wafer's effective area. Furthermore, the smaller marking area does not affect the stability of subsequent wafer processing, and is beneficial for the uniformity of subsequent wafer electroplating and deposition layers, thereby improving wafer quality. Moreover, the processing of the wafer marking area is convenient and reliable. Attached Figure Description

[0023] Figure 1 This is a flowchart of a method for processing the marking portion of a wafer according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of wafer bonding to a glass substrate according to an embodiment of the present invention;

[0025] Figure 3 for Figure 2 Side view;

[0026] Figure 4 This is a schematic diagram of a structure formed in a predetermined area of ​​a wafer using a stealth laser process according to an embodiment of the present invention.

[0027] Figure 5 for Figure 4 Side view;

[0028] Figure 6 The laser reciprocating scanning path for the stealth laser process according to an embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram illustrating the partial debonding between the wafer and the glass substrate according to an embodiment of the present invention;

[0030] Figure 8 for Figure 7 Side view;

[0031] Figure 9 This is a schematic diagram of another direction for debonding a portion of the wafer and the glass substrate according to an embodiment of the present invention;

[0032] Figure 10 for Figure 9 Side view;

[0033] Figure 11 This is a schematic diagram of a graphite carrier plate for vacuum adsorption on a wafer.

[0034] Figure 12 This is a schematic diagram illustrating the vacuum adsorption separation of a wafer and a glass substrate using a graphite substrate, according to an embodiment of the present invention.

[0035] Figure 13 This is a schematic diagram of the structure of a wafer with markings prepared according to an embodiment of the present invention;

[0036] Figure 14 This is a schematic diagram of the modified region remaining on the glass carrier plate according to an embodiment of the present invention.

[0037] Figure label:

[0038] Wafer 10, Marking area 110, Modified region S1,

[0039] Glass carrier 20, adhesive 30, debonding region S2, graphite carrier 40, adsorption pore 410, laser scanning path S3. Detailed Implementation

[0040] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0041] The steps described in the specification and the flowcharts in the accompanying drawings of this invention are not necessarily to be strictly followed according to the step numbers; the execution order of the steps can be changed. Furthermore, certain steps can be omitted, multiple steps can be combined into one step, and / or one step can be broken down into multiple steps.

[0042] like Figure 1As shown, the processing method of the marking portion 110 of the wafer 10 according to an embodiment of the present invention includes:

[0043] S100, bonding wafer 10 to glass substrate 20, such as Figure 2 and Figure 3 As shown;

[0044] According to some embodiments of the present invention, such as Figure 2 As shown, in step S100, adhesive 30 can be used to bond the wafer 10 and the glass substrate 20.

[0045] S200, using stealth laser technology, laser-modifies a predetermined area of ​​wafer 10 to form a modified region S1. The modified region S1 corresponds to the marked area 110, such as... Figure 4 and Figure 5 As shown; the “modified region S1 corresponds to the marking part 110” mentioned here can be understood as the laser modification of the area of ​​the pre-processed marking part 110 to form a modified region S1 of the same volume.

[0046] In some embodiments of the present invention, in step S200, a stealth laser process is performed from the side of the wafer 10.

[0047] For example, by adjusting the operating parameters of the stealth laser process, a modified region S1 is formed from the outside to the inside of the side of wafer 10.

[0048] It should be noted that, as Figure 6 As shown, during the stealth laser process, the laser modification depth is adjusted by adjusting parameters such as laser power, and the modification area S1 is scanned from the outside to the inside of the wafer 10 along the laser scanning path S3.

[0049] S300, at least the bonding connection between the modified region S1 and the glass substrate 20 is preserved, and the remaining parts between the wafer 10 and the glass substrate 20 are debonded, such as... Figures 7-10 As shown;

[0050] like Figure 7 and Figure 10 As shown, laser debonding can be performed on the portion between the wafer 10 and the glass substrate 20, excluding the modified region S1, to form the debonding region S2.

[0051] In some embodiments of the present invention, in step S300, the area of ​​the retained bonding connection sites is larger than the projected area of ​​the modified region S1. It should be noted that the area of ​​the retained bonding connection sites can be slightly larger than the projected area of ​​the modified region S1, so as to facilitate retaining the modified region S1 on the glass carrier 20 when separating the wafer 10 and the glass carrier 20.

[0052] S400, the wafer 10 and the glass substrate 20 are separated, so that the modified region S1 of the wafer 10 remains on the glass substrate 20, thereby forming the marking region 110 on the wafer 10, such as... Figures 11-14 As shown.

[0053] According to some embodiments of the present invention, such as Figure 11 and Figure 12 As shown, in step S400, a graphite carrier plate 40 with adsorption holes 410 is used to vacuum adsorb the wafer 10, thereby separating the wafer 10 from the glass carrier plate 20.

[0054] In some embodiments of the present invention, before laser modification of a predetermined portion of wafer 10 using stealth laser technology, the method further includes: grinding wafer 10 to a predetermined thickness range. For example, the predetermined thickness range of wafer 10 is 100–300 μm.

[0055] In some embodiments of the present invention, wafer 10 is a SiC wafer 10.

[0056] A method for fabricating a wafer 10 having a marking portion 110 according to an embodiment of the present invention includes:

[0057] A100, the marking portion 110 of the wafer 10 is prepared using the processing method of the marking portion 110 of the wafer 10 as described above;

[0058] A200, under the marking function of the marking part 110, performs the fabrication process of the front and back devices of wafer 10.

[0059] The present invention has the following beneficial effects:

[0060] The marking portion 110 of the wafer 10 prepared by this invention is small in size, thus avoiding waste of the effective usable area of ​​the wafer 10. Furthermore, the smaller marking portion 110 does not affect the stability of subsequent processing of the wafer 10, and is beneficial to the uniformity of subsequent electroplating and deposition layers, thereby improving the quality of the wafer 10. Moreover, the processing of the marking portion 110 of the wafer 10 is convenient and reliable.

[0061] The following describes in detail, with reference to the accompanying drawings, a specific embodiment of the method for processing the marking portion 110 of the wafer 10 according to the present invention and the method for fabricating the wafer 10. It is to be understood that the following description is merely exemplary and should not be construed as a specific limitation of the present invention.

[0062] like Figure 1 As shown, the processing method for the marking portion 110 of wafer 10 includes:

[0063] S100, using adhesive 30 to bond wafer 10 to glass substrate 20, such as Figure 2 and Figure 3 As shown; where wafer 10 is SiC wafer 10.

[0064] S200, using stealth laser technology, laser-modifies a predetermined area of ​​wafer 10 to form a modified region S1. The modified region S1 corresponds to the marked area 110, such as... Figure 4 and Figure 5 As shown;

[0065] In step S200, for example, by adjusting the operating parameters of the stealth laser process, a modified region S1 is formed from the outside to the inside of the side of the wafer 10. Figure 6 As shown, during the stealth laser process, the laser modification depth is adjusted by adjusting parameters such as laser power, and the modification area S1 is scanned from the outside to the inside of the wafer 10 along the laser scanning path S3.

[0066] It should be noted that before performing laser modification on the predetermined areas of wafer 10 using stealth laser technology, wafer 10 needs to be ground to a predetermined thickness range. For example, the predetermined thickness range of wafer 10 is 100–300 μm.

[0067] S300, at least the bonding connection between the modified region S1 and the glass substrate 20 is preserved, and the remaining parts between the wafer 10 and the glass substrate 20 are debonded, such as... Figures 7-10 As shown;

[0068] S400, the wafer 10 and the glass substrate 20 are separated, so that the modified region S1 of the wafer 10 remains on the glass substrate 20, thereby forming the marking region 110 on the wafer 10, such as... Figures 11-14 As shown.

[0069] like Figure 11 and Figure 12 As shown, in step S400, a graphite carrier plate 40 with adsorption holes 410 is used to vacuum adsorb the wafer 10, thereby separating the wafer 10 from the glass carrier plate 20.

[0070] A method for fabricating a wafer 10 having a marking region 110 includes:

[0071] A100, the marking portion 110 of the wafer 10 is prepared using the processing method of the marking portion 110 of the wafer 10 as described above;

[0072] A200, under the marking function of the marking part 110, performs the fabrication process of the front and back devices of wafer 10.

[0073] In summary, the marking portion 110 of the wafer 10 prepared by this invention has a small volume, thus avoiding waste of the effective usable area of ​​the wafer 10. Furthermore, the smaller marking portion 110 does not affect the stability of subsequent processing of the wafer 10, and is beneficial to the uniformity of subsequent electroplating and deposition layers, thereby improving the quality of the wafer 10. Moreover, the processing of the marking portion 110 of the wafer 10 is convenient and reliable.

[0074] Through the description of specific embodiments, a more in-depth and specific understanding should be gained of the technical means and effects adopted by the present invention to achieve the intended purpose. However, the accompanying drawings are only provided for reference and illustration and are not intended to limit the present invention.

Claims

1. A method for processing the marking area of ​​a wafer, characterized in that, include: S100, bonding the wafer to the glass substrate; S200, using stealth laser technology to laser-modify a predetermined area of ​​the wafer to form a modified area, the modified area corresponding to the marked area; S300, at least the bonding connection between the modified region and the glass substrate is preserved, and the remaining parts between the wafer and the glass substrate are debonded; S400, the wafer and the glass substrate are separated, and the modified region of the wafer is retained on the glass substrate to form a marking region on the wafer.

2. The method for processing the marking portion of a wafer according to claim 1, characterized in that, In step S100, an adhesive is used to bond the wafer and the glass substrate.

3. The method for processing the marking portion of a wafer according to claim 1, characterized in that, In step S200, a stealth laser process is performed from the side of the wafer.

4. The method for processing the marking portion of a wafer according to claim 3, characterized in that, By adjusting the operating parameters of the stealth laser process, the modified region is formed from the outside to the inside of the wafer's side surface.

5. The method for processing the marking portion of a wafer according to claim 1, characterized in that, In step S300, the area of ​​the retained bonding connection sites is larger than the projected area of ​​the modified region.

6. The method for processing the marking portion of a wafer according to claim 1, characterized in that, In step S400, the wafer is vacuum-adsorbed using a graphite carrier plate with adsorption pores, thereby separating the wafer from the glass carrier plate.

7. The method for processing the marking portion of a wafer according to claim 1, characterized in that, Before using stealth laser technology to laser-modify a predetermined portion of the wafer, the method further includes: grinding the wafer to a predetermined thickness range.

8. The method for processing the marking portion of a wafer according to claim 1, characterized in that, The preset thickness range of the wafer is 100 to 300 μm.

9. A method for processing the marking portion of a wafer according to any one of claims 1-8, characterized in that, The wafer is a SiC wafer.

10. A method for fabricating a wafer with an identification region, characterized in that, include: A100, the wafer marking portion is prepared using the wafer marking portion processing method as described in any one of claims 1-9; A200, under the marking function of the marking area, performs the fabrication process of the front and back devices of the wafer.

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