JP2001196281A - Marked semiconductor wafer for market - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor wafer whose marking does not exert bad influence upon itself in the middle of manufacture and which is hardly influenced by the surface treatment applied in each process of manufacture of itself. SOLUTION: A wafer is made into a wafer fitted with a very small ID mark which makes a plurality of very small ID marks A1 and A2 function as backup with each other by giving it a plurality of very small ID marks A1 and A2. Hereby, the necessity of feeling anxiety about the confusion or disability of trace caused by the disappearance of an extremely small mark vanishes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer provided with a marking for accurately identifying the semiconductor wafer.

[0002]

2. Description of the Related Art When a semiconductor wafer such as a silicon wafer is manufactured, if it is found during the manufacturing or after shipment that a certain malfunction has occurred in the wafer, the cause of the malfunction is reliably determined. Therefore, it is very important to communicate this to the manufacturing site properly.

In order to accurately perform such feedback, it is necessary that individual wafers to be manufactured can be individually identified. For this reason, the initial stage of the semiconductor wafer manufacturing process is required. At this stage, marking is performed on each wafer.

[0004] This marking is generally performed by engraving a predetermined mark on a predetermined portion of a semiconductor wafer. As a marking device therefor, for example, a laser marking device is used. JP-A-59-23512, JP-A-2-175154, etc.).

[0005] Also, the mark given to each wafer is:
A typical example is an ID number of each wafer. However, a mark such as a bar code, a character, or a number may be provided on the wafer surface as a clue to know the processing conditions, processing history, or electrical characteristics up to that time. In this way, the marking can be used not only for tracing the defect route, but also for process control and production control. Can be surely identified.

[0006]

However, since the marking process applies some physical action to the wafer being manufactured, slip marking may occur on the wafer due to the marking operation. is there. For this reason, it is preferable that marking be performed on a minute scale in order to prevent the wafer from being adversely affected.

On the other hand, it is preferable to add a minute mark from the viewpoint of not adversely affecting the wafer, but the minute mark is a surface treatment applied in each step of semiconductor wafer manufacturing. There is a drawback that it is easy to disappear. In this regard, the production of semiconductor wafers is, of course, performed in a flow operation, and it is extremely difficult to return the semiconductor wafer to its original state if it is mistakenly attached.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a semiconductor device which does not adversely affect a wafer in the course of manufacturing and which is not affected by surface treatment performed in each step of semiconductor wafer manufacturing. An object of the present invention is to provide a semiconductor wafer for distribution which is hard to receive.

[0009]

In order to achieve the above object, according to the present invention, a distribution semiconductor wafer having the same mark formed at two or more locations is provided. By functioning as a backup in the case of disappearance, even if the mark has disappeared due to surface treatment performed in each step of semiconductor wafer manufacturing, it can be surely and quickly revived. Features.

[0010] More specifically, the present invention provides the following.

(1) A distribution semiconductor wafer having essentially the same mark formed at two or more locations.

The term "distribution semiconductor wafer" means a semiconductor wafer that is widely distributed as a commercial product, not only for testing and research.

(2) The marks formed at two or more positions are arranged at positions different from each other in a surface processing speed in the same processing in a semiconductor wafer manufacturing process. Semiconductor wafers for distribution.

(3) The distribution semiconductor wafer according to (2), wherein the marks formed at two or more positions are respectively arranged on the front side and the back side of the semiconductor wafer.

[0015] The above "front side and back side" is a concept indicating both sides located on the opposite side across the edge, and the "front side" and "back side" include not only the front side and the back side but also the front side and the back side. It also includes the front and rear faces.

(4) The semiconductor wafer for distribution according to any one of (1) to (3), wherein the marks formed at two or more places are arranged near each other.

(5) The marks formed at two or more locations are arranged at locations where they can be read simultaneously by one optical reading device. Or a semiconductor wafer for distribution.

(6) The distribution according to any one of (1) to (5), wherein each of the marks formed at two or more locations is a dot mark composed of minute dots having a diameter of 1 μm to 13 μm. For semiconductor wafer.

(7) The mark is the I mark on the semiconductor wafer.
The distribution semiconductor wafer according to (6), which is a D mark.

(8) The semiconductor wafer for distribution according to (6) or (7), wherein the predetermined mark is a mark provided on an inner wall surface of the notch.

(9) The distribution semiconductor wafer according to (6), wherein the mark is a mark for alignment.

(10) The distribution semiconductor wafer according to (6), wherein the mark is a mark indicating a direction of a crystal in the distribution semiconductor wafer.

(11) The distribution semiconductor wafer according to (9) or (10), which is a perfect circular wafer.

In short, a “perfectly circular wafer” means that the notch has an orientation flat (orientation flat).
Also means a wafer that does not exist.

(12) A wafer carrier in which the distribution semiconductor wafer described in (5) is stored with the mark directions aligned.

(13) In marking and marking a semiconductor wafer by forming a predetermined mark on the semiconductor wafer in the process of manufacturing and processing the semiconductor wafer, essentially the same mark is formed at two or more locations on the semiconductor wafer. A method using a marked semiconductor wafer.

(14) When a predetermined mark is formed on a semiconductor wafer in the process of manufacturing and processing the semiconductor wafer, essentially the same mark is formed at two or more locations on the semiconductor wafer. A method for applying a marking to negate the disadvantage caused by the substantial disappearance of any one of the marks caused by the manufacture and processing of a semiconductor wafer.

Regarding the concept of “semiconductor wafer manufacturing / working process”, in this specification, “semiconductor wafer manufacturing process” includes all processes related to semiconductor wafer manufacturing. The “semiconductor wafer processing process” includes processes related to the processing of the semiconductor wafer manufactured in the semiconductor wafer manufacturing process, such as the process of processing the semiconductor wafer manufactured in the semiconductor wafer manufacturing process into semiconductor devices. Everything is included.

"Substantial disappearance" or "substantial disappearance"
This is a concept that includes not only the case where the mark has completely disappeared, but also the case where it is difficult to read and detect the mark even if the mark has not completely disappeared. It is. Also, in this specification, when simply saying "disappearance", not only when the mark has completely disappeared, but also when reading and detecting the mark even if the mark has not completely disappeared. In some cases. "Essentially the same mark" includes not only completely the same mark but also a mark in which the portions necessary to identify the semiconductor wafers are the same and other additional portions are different. It is a concept. As such a device, there can be cited one in which the portions indicating the lot number and the serial number of the semiconductor wafer are the same and only the portion indicating the number of times of restoration is different. Therefore, in the embodiment of the present invention, the form in which the substantially remaining other marks are completely copied to another place may be used to distinguish the semiconductor wafers from the substantially remaining other marks. In this case, a necessary part is extracted, and a part obtained by appropriately changing the additional part is added to the part, and the part is stamped in another place.

The "predetermined mark" is typically an ID number of each wafer, but also includes a mark such as a bar code, a character, or a number indicating a processing history of the wafer. It is. Further, the “predetermined mark” may be a registered trademark.

The present invention basically relates to the processing of a wafer, and this processing can be performed irrespective of the constituent components of the wafer. Not limited to In the present invention, the processing after slicing such as a wafer having a different raw material such as a compound semiconductor wafer in the first place, a wafer having a different ingot manufacturing process such as a nitrogen-doped wafer, and an epitaxially grown epi-wafer is specially performed. Various types and forms of wafers, such as simple wafers, can be targeted.

Further, if the above points are generalized, the present invention is not limited to a "wafer" but may be applied to a general "substrate" such as a "liquid crystal substrate" as follows. Can be applied to

(15) A distribution substrate having essentially the same marks formed at two or more locations.

(16) In the process of manufacturing and processing a substrate, when marking is performed on the substrate by forming a predetermined mark on the substrate, a marking that forms essentially the same mark at two or more locations on the substrate is used. Method using a substrate that has been subjected.

(17) When marking is performed on a substrate by forming a predetermined mark on the substrate in a process of manufacturing and processing the substrate, a marking that forms essentially the same mark at two or more locations on the substrate is used. A method of nullifying a disadvantage caused by a substantial disappearance of any one of the marks caused by manufacturing and processing of the substrate.

In the method for reproducing a mark on a substrate according to the above (15), the above-mentioned restrictions (2) to (11) can be added as appropriate.

[0037]

Embodiments of the present invention will be described below with reference to the drawings.

[Marking Apparatus] In carrying out the marking method according to the present invention, any marking apparatus currently used can be used. In this embodiment, a laser marking apparatus is a typical example. I'll give you

As shown in FIG. 1, a laser marking apparatus generally includes an optical element 11 including a laser beam introduction optical system and a lens for forming a mask shape, a liquid crystal mask 13, and a laser beam. And a projection lens 14 for forming an image of the liquid crystal mask 13 at a predetermined position on the wafer W.

According to such a laser marking device, the projection position of the projection lens 14 is adjusted, an image corresponding to the mark to be added is formed on the liquid crystal mask 13, and the desired marking is performed by performing laser irradiation. Can be.

The laser marking device described in Japanese Patent Application No. 11-19737 is particularly suitable in that it can form extremely small marks.

[Reading Device] The mark formed on the wafer W by the laser marking device as described above is read by the reading device.

As shown in FIG. 2, a general reading apparatus irradiates a laser beam from a light source 21 to a mark on a wafer W, forms an image of reflected light from the mark by an imaging lens 23, and forms an image. The mark on the wafer W is read by detecting the formed image with the camera 24.

Here, the mark on the wafer W is, for example, as shown in FIG. 3, and such a mark is read by the reading device shown in FIG.

[Position of Mark] As shown in FIG.
In this embodiment, two marks are provided on the inner wall of the notch 31 of the wafer W (FIG. 4A).
A1 and A2, and B1 and B2 in FIG. 4B).

FIG. 5 is an enlarged cross-sectional view of the wafer W. As shown in FIG. 5, candidates for a place where a mark can be added include, for example, a front surface 31a, a front bevel surface 31b, and an edge. FIG. 4 shows a portion 31c, a back bevel surface 31d, and a back surface 31e.
The two marks A1 and A2 in (A) are different from each other in the circumferential position of the mark, the mark A1 is formed at the position of the frontal bevel surface, and the mark A2 is formed at the edge portion. , The positions in the height direction are also set to be different.

Similarly, also in FIG. 4B, the two marks B1 and B2 have the mark B1 formed at the position of the front bevel surface, while the mark B2 is formed at the position of the back bevel surface. .

Here, as will be proved in the embodiments described later,
When the wafer is subjected to the surface treatment during the manufacturing process, the degree of disappearance of the mark is different not only between the front surface and the back surface, but also between the back surface and the front bevel surface. It is recognized that the degree of disappearance of the mark differs depending on the type of manufacturing process in which the wafer is provided.

In view of the above, according to the present invention, by forming marks at two or more locations and making them function as backups for each other, the marks have been completely erased.
Alternatively, if the erasure has progressed to such a degree that it cannot be read by the reader even if it has not completely disappeared, the same mark as the other remaining mark is referred to while referring to the other remaining mark. A return is performed by newly attaching.

As described above, according to the present invention, the state of "two or more marks" is always ensured, thereby avoiding troubles such as mistakes due to disappearance of marks in the manufacturing process and inability to trace. They are able to do things.

[Marked Wafer] In the above embodiment, two marks are provided for each marked wafer.
Although an example in which the mark is formed in three places is shown, this mark may be formed in three or more places.

It is preferable from the viewpoint of improving the processing efficiency that the plurality of marks should be concentrated on the positions that can be read simultaneously by one reading device, since the detection efficiency is improved. For the same reason, in the case where a plurality of wafers W are stored in the wafer carrier 41 in order to carry them, it is preferable to align the positions of the marks of the plurality of wafers W (FIG. 6A →
(B)).

When a new mark identical to the lost mark is formed in order to restore the lost mark, especially when the lost mark has not completely disappeared. In order to avoid interference therewith, it is preferred that the new mark is formed at a different location from the location where it was previously marked. At this time, even if it is formed in a place different from the place where the mark was made before, if it is formed near the place where the mark was made before, the field of view of the reading device Can be secured.

[0054]

EXAMPLE The same mark having a width of 320 μm was formed on the front surface, front bevel surface, front bevel surface inside the notch, and back bevel surface inside the notch, respectively, of the wafer W, and a 1 μm copper thin film was laminated thereon. CM
P (Chemical Mechanical Polishing) processing was performed, and the degree of disappearance of marks (the degree of remaining) was observed after laminating the copper thin film and after the CMP processing.

The results are shown in Table 1 below.

[0056]

[Table 1]

According to the results shown in Table 1, when the CMP treatment was performed, the back side of the notch was not
It can be seen that the marks have good survivability irrespective of the outside and function as a backup for the marks on the front side. vice versa,
If the mark on the back surface has disappeared due to dirt on the back surface or the like, the mark on the front surface functions as a backup for the mark on the back surface.

Regardless of whether or not it is within the notch, if the distance in the circumferential direction is sufficiently short, the mark on the omote bevel surface and the mark on the urabebel surface can be sufficiently contained in the same visual field of the camera. Since it is possible, even when a plurality of marks are arranged at positions where the backup functions are mutually performed, it can be understood that simultaneous observation by one camera can be performed.

[0059]

According to the semiconductor wafer according to the present invention as described above, a plurality of marks are formed so as to function as a backup for each other. There is no need to worry about confusion or trace inability due to the disappearance.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a functional configuration of a general laser marking device.

FIG. 2 is a block diagram illustrating a functional configuration of a general reading device.

FIG. 3 is a diagram illustrating an example of a mark.

FIG. 4 is a diagram for explaining a position of a mark.

FIG. 5 is an enlarged cross-sectional view for explaining a position of a mark.

FIG. 6 is a diagram for explaining storage of a wafer in a wafer carrier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Optical element 13 Liquid crystal mask 14 Projection lens 21 Light source 23 Imaging lens 24 Camera 31 Notch of wafer W 31a Front side 31b Front side bevel side 31c Edge part 31d Back side bevel side 31e Back side 41 Wafer carrier W Wafer A1, A2, B1, and B2 mark

Claims (17)

[Claims] 1. A distribution semiconductor wafer having essentially the same mark formed at two or more locations. 2. The mark formed at two or more places,
2. The distribution semiconductor wafer according to claim 1, wherein the surface treatment speeds are different from each other in the same process in the semiconductor wafer manufacturing process. 3. The mark formed at two or more places,
3. The semiconductor wafer for distribution according to claim 2, wherein the semiconductor wafer is arranged on the front side and the back side of the semiconductor wafer. 4. The mark formed at two or more places,
4. The semiconductor wafer for distribution according to claim 1, wherein the semiconductor wafers are arranged close to each other. 5. The mark formed at two or more places,
The distribution semiconductor wafer according to any one of claims 1 to 3, wherein the distribution semiconductor wafers are arranged at locations where they can be read simultaneously by one optical reader. 6. The mark formed at two or more places,
6. A dot mark composed of minute dots each having a diameter of 1 μm to 13 μm.
The semiconductor wafer for distribution according to any one of the above. 7. The semiconductor wafer for distribution according to claim 6, wherein said mark is an ID mark of a semiconductor wafer. 8. The semiconductor wafer for distribution according to claim 6, wherein the predetermined mark is a mark provided on an inner wall surface of a notch. 9. The distribution semiconductor wafer according to claim 6, wherein the mark is a mark for alignment. 10. The distribution semiconductor wafer according to claim 6, wherein the mark is a mark indicating a direction of a crystal in the distribution semiconductor wafer. 11. The distribution semiconductor wafer according to claim 9, which is a perfect circular wafer. 12. A wafer carrier in which the distribution semiconductor wafer according to claim 5 is stored with the mark directions aligned. 13. A marking for forming essentially the same mark at two or more locations on a semiconductor wafer when the semiconductor wafer is marked by forming a predetermined mark on the semiconductor wafer in a process of manufacturing and processing the semiconductor wafer. Using a semiconductor wafer that has been subjected to aging. 14. A marking for forming essentially the same mark at two or more locations on a semiconductor wafer when marking the semiconductor wafer by forming a predetermined mark on the semiconductor wafer in a process of manufacturing and processing the semiconductor wafer. The production of semiconductor wafers
A method for negating a disadvantage caused by substantial disappearance of any one mark caused by processing. 15. A distribution substrate having essentially the same mark formed at two or more locations. 16. A method of forming a predetermined mark on a substrate in a process of manufacturing and processing the substrate to perform marking on the substrate by applying a marking for forming essentially the same mark at two or more locations on the substrate. How to use a substrate that has been made. 17. When marking a substrate by forming a predetermined mark on the substrate in a process of manufacturing and processing the substrate, marking is performed to form essentially the same mark at two or more locations on the substrate. A method for nullifying disadvantages caused by substantial disappearance of any one of the marks caused by the manufacture and processing of the substrate.