TW201316425A - Detection method of wafer breaking - Google Patents

Abstract

The present invention is a detection method of wafer breaking which acquires the images of scribe lines and its two side regions of a wafer waiting to be broken in the breaking space of a bearer from an image acquisition device before the wafer is broken, and acquires the images of scribe lines and its two side regions of the wafer in the breaking space of the bearer during the breaking period. The gradient difference ratio of the gray level histogram of the images of scribe lines and its two side regions of the wafer before and after the wafer is broken is analyzed via a gray level comparison means by the computer to determine whether the wafer has been broken completely, or the difference ratio of the gray level histogram of the images of scribe lines and its two side regions of the wafer during the wafer breaking period is analyzed via the gray level comparison means by the computer to determine whether the wafer has been broken completely to enhance the accuracy of automatic detection of wafer broken completely or not.

Description

Wafer splitting detection method

The invention relates to a wafer cracking detection method, in particular to a method for utilizing a difference ratio of image light and dark gray scales before wafer splitting and splitting, or a difference between light and dark gray scales on both sides of a cut track during wafer splitting. The analysis of the ratio is used to determine whether the wafer is completely broken or not.

At present, in the fabrication process of a semiconductor device, the wafer is mainly divided into a plurality of crystal grains by means of splitting, and the crystal grains are displaced and fixed on the carrier and electrically connected, and the steps of sealing and forming are successively performed. A semiconductor component having a specific function is completed.

In the above-mentioned wafer splitting step, in order to judge whether the wafer is completely split or not, the early inspection is performed by a high-magnification magnifying glass through the eye, and the human eye judges the mode because of the speed of the work and the high error rate. problem. At present, some people use a computer with a video capture device such as CCD to visually examine the judgment technique of the change of the size of the scribe line before and after the wafer splitting, instead of the human eye inspection operation, to improve the efficiency of wafer splitting inspection.

However, the above-mentioned computer using a video capture device such as a CCD to visually examine the change in the size of the scribe line before and after the wafer splitting can achieve the purpose of detecting whether the wafer is split or not, but before and after the wafer is split. The size of the scribe line changes very little, so that it is easy to affect the correctness of the computer visual automatic inspection system in image comparison judgment.

The main object of the present invention is to provide a wafer splitting detection method, and to provide another method for detecting wafer cracking with high accuracy.

In order to achieve the foregoing object, the wafer splitting detection method proposed by the present invention comprises: an image capturing step before a wafer splitting, and the wafer on the wafer splitting machine carrier is not splitting. Before, the computer-controlled image picker picks up the image of the wafer to be split and cut at the cracking space of the carrier and the side of the splitting and cutting road from the bottom of the carrying platform, and the front of the wafer is split. The image data is transferred to the computer for storage; a wafer splitting step is performed by a computer controlled wafer splitting machine, and the upper cutting edge applies an impact force to the predetermined cutting track position of the wafer to make the wafer edge The impacted cleavage path splits, and defines the time when the boring tool descends to the cleavage height to impact the predetermined scribe line position of the wafer and splits the wafer to be the splitting action time section; the image taking step when the wafer is splitting The computer-controlled image picker picks up the image of the wafer splitting cleavage and the splitting cleavage road at the cracking space of the bearing platform from the bottom of the cleavage time zone. Image data of the time zone of the wafer splitting action Send to the computer for storage; and a computer analysis image step, the computer analyzes the wafer splitting and splitting of the wafer before and after the splitting of the wafer by the light and dark gray scale comparison means. The contrast ratio of the light and dark gray scale of the regional image. When analyzing and judging the wafer splitting and cutting time of the wafer before the splitting and the splitting time zone, the difference between the light and dark gray scales of the image of the two sides is greater than or equal to 5%. When it is determined that the cleavage of the wafer is completely split, if the analysis determines that the ratio of the light-dark gray gradation of the wafer splitting cleavage and the images on both sides of the wafer before the splitting and the splitting time zone is smaller than At 5%, it was determined that the cleavage of the wafer was not completely split.

Another wafer splitting detection method proposed by the present invention comprises: a wafer splitting step, wherein the computer-controlled wafer splitting machine is configured to apply a predetermined cutting path position of the wafer from top to bottom. An impact force that causes the wafer to split along the impacted scribe line, and defines a time during which the cleavage to the cleavage height impacts the predetermined scribe line of the wafer and causes the wafer to split to be a splitting time section; The image capturing step of the circular splitting action is performed by a computer controlled image picker in the splitting action time section from the lower side of the carrying platform to take up the wafer splitting cutting path at the cracking space of the carrying platform. Side image, and the image data of the wafer splitting time section is transmitted to the computer for storage; and a computer analysis image step is performed by the computer to analyze the pre-cracking and splitting action of the wafer by the light and dark gray scale comparison means The difference between the brightness and darkness of the image on both sides of the wafer in the time segment is analyzed. The difference between the brightness and darkness of the image on both sides of the wafer splitting and cutting channel in the wafer splitting time zone is analyzed and judged. When the ratio is greater than or equal to 5% Determining that the cleavage of the wafer is completely split by the cleavage of the wafer; if the analysis determines that the ratio of the light and dark gradation of the image on both sides of the wafer cleavage scribe line of the wafer splitting time zone is less than 5%, the wafer is judged to be The splitting of the cutting path is not completely split.

The wafer cleaving detection method is designed by using the automatic detection method combined with the wafer splitting mechanism to shorten the detection time for determining the wafer splitting, and more importantly, the wafer of the present invention. The cleaving detection method uses the computer to capture the image before the cleaving and the action time segment of the wafer, and analyzes and judges the ratio of the difference between the dark and the gray gradation, the wafer cleaving dicing and/or the wafer cleaving dicing The ratio of the light and dark gray scales of the side area image determines whether the wafer is completely cleaved, or directly uses the computer to capture the image of the wafer splitting time section, and analyzes and judges the difference ratio of the light and dark gray scales. The ratio of light and dark gray scales on both sides of the cracked scribe line determines whether the wafer is completely cleaved, which makes it possible to effectively improve the accuracy of determining whether the wafer is completely split.

FIG. 1 is a flow chart showing a preferred embodiment of the wafer splitting detection method of the present invention. The wafer splitting detection method of the present invention is used for positioning and positioning on a splitting machine carrier. The wafer on the wafer is determined to be completely broken after the pre-cutting cleavage is cleaved. The implementation step of the wafer cleavage detection method includes: an image taking step before the wafer is split, and a wafer splitting a step, an image taking step when a wafer is split, and a computer analysis image step, wherein:

The image capturing step before the wafer splitting is performed by a computer controlled image capturing device (eg, CCD, etc.) before the wafer positioned on the carrier of the splitting machine is not split. The image of the wafer to be split and cut at the cracking space of the carrier and the two sides of the wafer are taken from the bottom to the bottom of the table, and the image data before the wafer is transferred to a computer for storage. At the same time, an auxiliary forward side light source may be projected from the image picker side below the carrying platform to the splitting space of the carrying platform, or an auxiliary backlight may be projected from the top of the wafer to the splitting cutting track position.

The wafer splitting step is performed by a computer controlled by the computer. The file of the wafer splitting machine applies an impact force to the predetermined cutting track position of the wafer from top to bottom, so that the wafer is generated along the impacted cutting path. Splitting, and defining the falling edge of the file to impact the predetermined scribe line position of the wafer and splitting the wafer for a period of time.

The image capturing step of the wafer splitting action is performed by a computer-controlled image picker to draw the wafer at the cracking space of the carrying platform from the bottom to the bottom of the splitting time zone. The image of the dicing road and the two sides thereof are split, and the image data after the splitting of the wafer is transmitted to the computer for storage, and the image can be taken from the image picker side under the carrying platform The auxiliary side light source is projected at the cleft space, or the auxiliary backlight may be projected from the top of the wafer to the position of the cleaving scribe line. The computer analyzes the image step, and the computer analyzes the crystal by light and dark gray scale comparison means. The difference between the light and dark gray scales of the image of the wafer splitting cleavage and the images on both sides before and after the splitting, when the difference ratio analysis determines the wafer splitting cleavage and its sides before and after the wafer splitting When the ratio of light and dark gray scale difference of the image is greater than or equal to 5%, it is determined that the cleavage of the wafer is completely split, and if the analysis determines the wafer splitting cleavage before and after the wafer splitting, The difference between the brightness and darkness of the image on the side is less than 5%. When it is determined that the cleavage of the wafer is not completely split, the wafer splitting step must be performed again.

The following further illustrates by way of example, as shown in FIG. 2, the method of taking the image before the splitting of the wafer 2 is disclosed, wherein the wafer 2 positioned on the splitting machine carrier 1 is not cleaved before being used by the computer. The image capturing device 3 controls the image of the wafer 2 to be split and the dicing street 20 and the two sides of the wafer 2 at the cracking space of the carrier 1 from the bottom of the carrier 1 and the wafer 2 is ruptured. The image data is transmitted to the computer for storage. When capturing the image, the auxiliary forward side light source 4 or the auxiliary backlight source 5 can provide illumination. The image before the split of the wafer 2 is as shown in FIG. 3 (refer to Appendix A, picture A).

In the case of wafer splitting, the following states can be distinguished, among which:

As shown in FIG. 4, when the boring tool 6 does not split the wafer 2, the image pickup device 3 is controlled by the computer to draw the wafer 2 at the cracking space of the carrying platform 1 from the bottom of the carrying platform 1 from below. The image of the dicing street 20 and the two sides thereof are split, and the image data of the wafer 2 is split and transferred to a computer for storage. When the image is captured, the auxiliary side light source 4 or the auxiliary backlight source 5 can be illuminated. The image of the wafer splitting action is shown in Figure 5 (refer to Appendix B, picture B). The wafer is analyzed by the computer to analyze the wafer 2 before and after the splitting of the wafer. The difference between the brightness and darkness of the image on the 20th and the two sides of the image, wherein the wafer 2 is cracked after the wafer 2 is cracked, and there is no crack in the 20 cleavage road. Therefore, the computer judges the wafer according to the image analysis obtained. There is no significant difference between the images before and after the cracking, that is, when the ratio of the difference between the light and dark gray scales is less than 5%, it is determined that the wafer is not split.

As shown in FIG. 6, when the boring tool 6 splits the wafer 2, the wafer 2 is cracked from the split cleavage trajectory 20 and the wafer 2 is lifted in one side, and the computer controlled image picker is self-supporting. 1 below, the image of the wafer to be cleaved and secrated at the cracking space of the carrying platform 1 and the two sides thereof are captured from the bottom to the top, and the image data of the wafer 2 is split and transferred to a computer for storage. When the image is captured, illumination can be provided by the auxiliary forward side light source 4 or the auxiliary backlight source 5, and the image of the wafer 2 when splitting is shown in FIG. 7 (refer to the attached picture C), and then connected by the computer to the light and dark gray. The step ratio method is used to analyze the difference ratio of the light and dark gray scales of the wafer splitting trajectory 20 and the images on both sides of the wafer before and after the splitting of the wafer 2, wherein the wafer splitting and cutting channel after the wafer 2 is split There are cracks in 20, and the fracture surface on one side of the cleavage trajectory 20 through the wafer 2 produces a distinct dark band 8 under the refracting of the light, and the bright band 7 is maintained on the other side, and the corresponding section produces a light and dark before the wafer is split. Difference, so the computer judges that the image before and after the cleaving of the wafer 2 has a distinct gray-dark difference, that is, the other The difference between the brightness and darkness of the gray scale is greater than 5%, and it is determined that the wafer 2 is completely split.

As shown in FIG. 8, when the trowel 6 splits the wafer 2, the wafer 2 is cracked from the cleavage cutting channel 20, and the two sides of the wafer 2 are respectively lifted up, and the computer controls the image picker 3 at this time. The image of the wafer 2 to be cleaved on the cleavage cutting path 20 and the two sides of the wafer 2 at the cracking space of the carrying platform 1 is taken up from the bottom of the loading platform 1 and the image data of the wafer 2 is split and transmitted to the computer. The medium is stored, and when the image is captured, the auxiliary forward side light source 4 or the auxiliary backlight source 5 can be provided with illumination. The image of the wafer 2 when splitting is shown in FIG. 9 (refer to the attached picture D), followed by the computer. The difference between the brightness and darkness of the image of the wafer splitting trajectory 20 and the images on both sides of the wafer 2 before and after the splitting of the wafer 2 is analyzed by the light and dark gray scale alignment method, wherein the wafer 劈 after the wafer 2 is split There are cracks in the cracked trajectory 20, and the fracture surface on both sides of the cleavage trajectory 20 through the wafer 2 produces a distinct dark band 8 under the refracting of the light. If the boring tool penetrates the wafer 劈 scribe line 20, the wafer 劈 is cut. The bright band 9 is generated at the road 20, and the corresponding section of the wafer before the splitting produces a difference in brightness and darkness, so the computer judges the crystal according to the captured image analysis. 2 before and after the image splitting significant difference in shade of gray, i.e. gray scale brightness differences between each other ratio greater than 5%, and further determines the wafer 2 has been completely cleaved.

As shown in FIG. 10, it is a flowchart showing another preferred embodiment of the wafer splitting detection method of the present invention. The implementation step of the wafer splitting detection method includes: a wafer splitting step, a The image capturing step during wafer splitting and a computer analysis image step, wherein:

The wafer splitting step is performed by a computer controlled wafer splitting machine. The upper razor applies an impact force to the predetermined scribe line position of the wafer to cause the wafer to split along the impacted cutting channel, and The period during which the cleavage to the cleavage height impacts the predetermined scribe line of the wafer and the wafer is split is defined as the cleavage time zone.

The image capturing step of the wafer splitting is performed by a computer controlled image picker in the splitting time section from the lower side of the carrying platform to take up the wafer splitting and cutting at the cracking space of the carrying platform. The image on both sides of the road, and the image data of the wafer splitting time section is transmitted to the computer for storage, and the image can be taken from the image picker side under the carrying platform The auxiliary side light source is projected at the space, or the auxiliary backlight may be projected from the top of the wafer to the position of the splitting scribe line.

The computer analysis image step is performed by a computer to analyze the difference ratio of the light and dark gray scales of the image on both sides of the wafer splitting scribe line in the wafer splitting time section by the light and dark gray scale comparison means, as shown in FIG. 7 and Referring to Figure C of Annex I, when the analysis determines that the ratio of the difference between the light and dark gray scales of the image on both sides of the wafer splitting scribe line in the wafer splitting time section is greater than or equal to 5%, it is determined that the wafer is split. The scribe line is completely cleaved; if the ratio of the light and dark gradation of the image on both sides of the wafer splitting scribe line in the wafer splitting time section is less than 5%, the cleavage of the wafer is not completely determined. crack.

It can be seen from the foregoing description that the method for detecting the crack detection of the wafer in the prior art is adopted by the automatic detection method and combined with the wafer splitting mechanism, which can effectively shorten the cracking of the wafer into a plurality of crystal grains. Process time, and more importantly, the wafer cleaving detection method of the present invention uses a computer to compare and determine the light and dark gray scale alignment analysis means for the image captured by the wafer before the splitting and splitting time zone The ratio of the gray scale difference ratio is judged or judged, or the difference ratio of the light and dark gray scales of the images on both sides of the wafer scribe line in the image captured by the wafer splitting time section is made, so that the judgment crystal can be improved The accuracy of whether the circle is completely split provides an automated and accurate method for wafer cleaving detection for wafer cleaving in semiconductor component fabrication processes.

The above is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any one of ordinary skill in the art can use the present invention without departing from the technical features of the present invention. Equivalent embodiments of the local changes or modifications made by the disclosed technology are still within the scope of the technical features of the present invention.

1. . . Carrying platform

2. . . Wafer

20. . . Splitting and cutting

3. . . Image capture device

4. . . Auxiliary positive side source

5. . . Auxiliary backlight

6. . . chopper

7. . . Bright band

8. . . Dark band

9. . . Bright band

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart showing a preferred embodiment of the wafer splitting detection method of the present invention.

2 is a schematic plan view showing the wafer cleavage detecting method of the present invention before the wafer splitting.

FIG. 3 is a schematic view of the image taken before the wafer is cracked in FIG. 2. FIG.

4 is a schematic plan view of the present invention for capturing an image when the wafer is not split.

FIG. 5 is a schematic view of the image taken when the wafer shown in FIG. 4 is not split.

FIG. 6 is a schematic plan view (1) of the present invention for capturing an image when the wafer is cleaved.

Fig. 7 is a schematic view showing the image taken during the splitting action of the wafer shown in Fig. 6.

FIG. 8 is a schematic plan view (2) of the present invention for capturing images during wafer splitting.

FIG. 9 is a schematic view showing the image taken during the splitting action of the wafer shown in FIG. 8. FIG.

Figure 10 is a flow chart showing another preferred embodiment of the wafer splitting detection method of the present invention.

Claims (8)

A wafer splitting detection method includes: an image capturing step before a wafer is split, and the image picker is controlled by a computer before the wafer on the wafer splitting machine carrier is not split. Obtaining images of the wafer to be split and cleavage at the cracking space of the substrate and the sides of the splitting and cutting road from the bottom of the carrying platform, and transmitting the image data before the wafer splitting to the computer for storage; The wafer splitting step is performed by a computer-controlled wafer splitting machine that applies a shock force to the predetermined cutting track position of the wafer from top to bottom, causing the wafer to split along the impacted cutting path, and Defining the time when the file is lowered to the splitting height and impacting the predetermined cutting track position of the wafer, and the time during which the wafer is split is the splitting action time section; the image capturing step when the wafer is splitting is controlled by the computer to control the image picker Extracting the image of the wafer splitting cleavage road at the cracking space of the bearing platform and the two sides thereof from the bottom of the cleaving time zone, and smashing the image data after the wafer is split Transfer to a computer for storage; and a computer to analyze images The computer analyzes the difference between the light and dark gray scales of the image of the wafer splitting cleavage and the sides of the split cleavage road before and after the wafer splitting by means of a light-dark gray-scale comparison method. When the ratio of the difference between the light and dark gray scales of the wafer cracking cleavage road and the image of the two sides before and after the crack is greater than or equal to 5%, it is determined that the cleavage of the wafer is completely split; if the wafer is analyzed and judged When the ratio of light and dark gray scales of the wafer splitting cleavage road and the images on both sides before and after the cracking is less than 5%, it is determined that the cleavage of the wafer is not completely split. The wafer splitting detection method according to claim 1, wherein the image capturing step before the wafer splitting and the image capturing step during the wafer splitting are included in the captured image. At the same time, an auxiliary forward side light source is projected from the image picker side below the carrying platform to the splitting space of the carrying platform. The wafer splitting detection method according to claim 1, wherein the image capturing step before the wafer splitting and the image capturing step during the wafer splitting are included in the captured image. At the same time, an auxiliary backlight is projected from the top of the wafer to the position of the splitting scribe line. The wafer splitting detection method according to claim 1, wherein the image capturing step before the wafer splitting and the image capturing step during the wafer splitting are included in the captured image. At the same time, an auxiliary backlight is projected from the top of the wafer to the position of the splitting scribe line, and an auxiliary forward side light source is projected to the splitting space of the carrying platform from the image picker side below the carrying platform. A method for detecting wafer cracking, comprising: a wafer splitting step, wherein a blade controlled by a computer controlled wafer splitting machine applies an impact force to a predetermined cutting track position of the wafer from top to bottom, Splitting the wafer along the impacted scribe line, and defining the time when the boring tool is lowered to the cleavage height to impact the predetermined scribe line position of the wafer, and the time during which the wafer is split is the cleavage action time section; The image capturing step is performed by a computer-controlled image capturing device for capturing an image of the sides of the wafer splitting and cutting road at the cracking space of the carrying platform from the bottom of the carrying table in the splitting time section. The image data of the wafer splitting time zone is transmitted to the computer for storage; and a computer analysis image step is performed by the computer to analyze the wafer splitting of the wafer splitting time section by means of light and dark gray scale alignment means The ratio of the difference between the light and dark gray scales of the image on both sides of the scribe line. When the analysis determines the ratio of the difference between the light and dark gray scales of the image on both sides of the wafer splitting scribe line in the wafer splitting time section is greater than or equal to 5%, the judgment is made. Wafer cracked Complete splitting; Analysis of the wafer is determined if the time segments of the wafer splitting splitting gray scale image brightness scribe line on both sides of the ratio is less than 5%, the wafer is cleaved determined scribe not completely cleaved. The wafer splitting detection method according to the fifth aspect of the invention, wherein the image capturing step of the wafer splitting action is included in the image capturing the image and the image below the carrying platform. The side of the extractor projects an auxiliary forward side light source to the splitting space of the carrying platform. The method for detecting a wafer splitting according to the fifth aspect of the invention, wherein the image capturing step of the wafer splitting is included in the image capturing, and the splitting is performed from above the wafer. The scribe line position projects an auxiliary backlight. The method for detecting a wafer splitting according to the fifth aspect of the invention, wherein the image capturing step of the wafer splitting is included in the image capturing, and the splitting is performed from above the wafer. The scribe line position projects an auxiliary backlight source, and an auxiliary forward side light source is projected to the cleavage space of the carrier from the image picker side below the carrier.