JP2558822B2 - Semiconductor wafer production control method and semiconductor wafer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a semiconductor wafer processing step, and particularly to a semiconductor wafer suitable for managing wafer manufacturing conditions, processing results, and processing results on a single-wafer basis. And a semiconductor wafer to which the production management method is applied.

[Conventional technology]

A conventional semiconductor wafer production management method is, for example, as disclosed in Japanese Patent Laid-Open No. 62-139316, which issues a control number each time a wafer lot is received and stores it for each processing / storage position. It has been proposed to transfer the data between the processing and storage positions, identify the control number that moves between the control units, and perform the corresponding processing in each unit.

Further, conventionally, a wafer carrier jig for storing a wafer for production control of the above semiconductor wafer is disclosed in, for example, Japanese Patent Laid-Open No.
As described in Japanese Patent Publication No. 213142, a plurality of types of wafers are formed by alternately forming, in the same wafer carrier, grooves having a shape suitable for wafers having different shapes such as a round shape and a square shape. It has been proposed to store them in the same wafer carrier.

Further, conventionally, for example, JP-A-62-248235 and JP-A-62-169409 disclose that the relationship between the wafer and the wafer carrier jig is defined by reducing the number of wafers that can be stored. As described above, there has been proposed one that manages the stored wafers by using a carrier identification mark (for example, a bar code) provided on the wafer carrier jig or a small processor.

[Problems to be Solved by the Invention]

In the above-mentioned conventional semiconductor wafer production management method, when a lot is received, a continuous management code corresponding to the lot is issued, and the single-wafer management is not taken into consideration. However, there is a problem that it is impossible to identify the wafer, and accordingly, there is a problem that it is impossible to collect the physical distribution unit, the manufacturing condition instruction, the processing result data, and the processing result data in the unit of single wafer.

Further, in the former wafer carrier jig of the above-mentioned prior art, when a wafer is processed or inspected, an identification code of the wafer carrier (for example, a lot number, a product code, a name of a processing step, a mechanic which describes a sequence, etc. ) Is read and grasped, the stored wafer is further extracted from the wafer carrier, and the type code and the wafer identification code that are engraved are directly read to compare the wafer and the identification code of the wafer carrier. .

Therefore, there is a problem that the work efficiency tends to decrease, the facility operating rate decreases, the amount of work in progress increases, the manufacturing period increases, etc., and the wafer diameter and wafer size in the semiconductor manufacturing process expected in the near future are increased. In automating the foliar processing, there are problems that the yield of the wafer is reduced due to the effect of chipping of the wafer on the risk of wafer damage and workability when taking out and storing the wafer, and that the manufacturing period is increased.

Further, in the latter prior art wafer carrier jig, it is not possible to omit the work of distinguishing the wafer carrier jig from the wafer taken out from the wafer carrier jig, which causes a problem of lowering work efficiency. there were.

An object of the present invention is to provide a wafer production management method that can instruct a manufacturing condition on a wafer-by-wafer basis and manage a processing result and a processing result in a wafer processing step, and a semiconductor wafer to which the production management method is applied. Especially.

[Means for solving the problem]

In order to achieve the above object, in the wafer production management method of the present invention, every time a wafer is processed in the exposure process, the identification code such as the wafer type, the No., and the processing process does not affect the processing of the wafer. The wafer is transferred to each part by photolithography, and the transferred identification mark is read in a processing step to identify the wafer in units of individual wafers.

[Action]

In the above-described wafer production management method of the present invention, since it is possible to collect data on manufacturing conditions, processing results, and processing results in single wafer units, it is possible to grasp the status of process progress in single wafer units. In addition, work-in-process control is possible, and in particular, the manufacturing period of a specific IC product can be shortened.

In addition, since it is possible to perform quality control on a sheet-by-sheet basis, it is possible to improve the accuracy of cause estimation by defect analysis and shorten the manufacturing period of adaptive control.

Further, since the correlation between the manufacturing condition and the processing result can be grasped on a sheet-by-sheet basis, the accuracy can be improved by adjusting the equipment.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the wafer 1 is used in this embodiment.
In the vicinity of the orientation flat 2 that does not affect the chip (not shown) that is the product of FIG. 3, a product type, a symbol that indicates the number of the wafer 1 and a symbol 3 that indicates that the process is completed are given. This symbol 3 is transcribed / etched by photolithography, and 20 characters can be transcribed on each of the left half 4 and the right half 5 of the figure, so that a total of 40 characters can be displayed.

As shown in the enlarged view of FIG. 2, reference numeral 3 is assigned to the left half 4 a symbol indicating the product type and the number of the wafer 1, and to the right half 5 a symbol indicating the completed exposure process.

Next, as shown in FIGS. 3A, 3B and 3C, the wafer 1 is stored in the wafer carrier jig 6 at the time of transfer. This wafer carrier jig 6 shuts off the front lid 7 for holding and fixing the wafer 1 to be stored and the wafer 1 from the outside air together with clean air, so that the symbol 3 written on the peripheral edge of the surface of the storage wafer 1 The carrier main body 8 is made of a material that can be directly transmitted from the outside. The front lid 7 has a packing 9 for securing adhesion to the wafer carrier body 8 fixed to the inner surface thereof, and a rear end portion of the shaped support plate 9 fixed thereto. The support plate 9 has an arc-shaped guide surface 9a at the tip of its upper surface so as to correspond to the outer peripheral surface of the wafer 1. Further, the front lid 7 has two leaf springs 10 fixed to its inner side surface so as to be inclined outward. These two leaf springs 10 are fixed to the inner side surface of the wafer 1 by interposing the outer peripheral portion of the wafer 1 and fixing the pair of wafer holders 11. Further, the front lid 7 is projected from both end surfaces thereof in parallel with each other, and its tip end portion is bent outwardly, and its tip end surface is fixed to the wafer carrier body 8 as shown in FIG. 3 (c). Two fittings 12 that are in contact with the mounting plate 8a are fixed, and a groove into which one end of a clip 14 formed by a leaf spring and having a shape on the outer surface is inserted is fixed to each of these fittings 12. Forming thirteen.

 Next, the operation of storing the wafer 1 will be described.

First, a part of the outer peripheral surface of the wafer 1 has two guide surfaces 9a.
When the wafer 1 is mounted on the support plate 9 so as to be inserted between two pairs of wafer holders 11, the wafer 1 is fixed by vibration or the like without sliding or rattling.

Next, when the wafer carrier body 8 inserts the wafer 1 and its tip portion contacts the rear end portion of the front lid 7 via the packing 9, the packing 9 brings the wafer carrier body 8 and the front lid 7 into close contact with each other. Are connected in a secured state.

At this time, since the two mounting members 12 and the two mounting plates 8a are in contact with each other, if the mounting members 12 and the mounting plate 8a are inserted with the clip 14 and one end portion thereof is inserted into the groove 13, the wafer carrier. The body 8 and the front lid 7 are integrally fixed by the elastic force of the clip 14.

In this state, when a vertical light beam (not shown) is applied to the wafer carrier body 8 from the outside, the wafer identification code formed on the wafer 1 is read by the reading device (not shown) through the wafer carrier body 8. You can In this case, the identification rate (misreading rate) of information transmitted through the wafer carrier body 8 may be equal to or lower than that of the bare wafer.

Next, FIG. 4 and FIG. 5 showing a case where the present invention is applied to a production management system for individual wafers will be described.

As shown in FIG. 4, in this embodiment, four sets of similar equipment groups A, B, each of which aggregates a plurality of manufacturing equipments of the same kind.
It is composed of C and D. Each of these similar equipment groups A, B, C, D
Is a plurality of equipment or equipment subgroup a ₁ … a _n , b _n b _n , c ₁ … C _n , d
It consists ₁ ... d _n, in particular, equipment group A, diffusion group, equipment group B, photo groups, equipment group C is photoetching group, facilities group D is a deposition group. Further, in the diffusion group A, the metal is oxidized and the impurities are diffused, and the equipment subgroup a ₁ ...
a _n is a diffusion furnace, an ion implantation device, a cleaning device,
It is composed of a dryer. In the photo group B, the patterns of wirings and electrodes are transferred by light, and the equipment subgroups b ₁ ... b _n that compose the photo group B are a photoresist coating device, a developing device, an aligner, and a dimension measuring device, respectively. Etc. In the photo-etching group C, metal etching is performed by a chemical reaction according to the photo-resist pattern formed in the photo-group B, and the equipment sub-groups c ₁ ... c _n constituting this photo-etching group C are etched.
Are each composed of an etching device, an asher device, an ozone removing device, a cleaning device, and the like. In the film forming group D, performs film formation of various metals, facilities subgroup d ₁ ... d _n constituting the deposition group D, respectively CVD device,
It is composed of a sputtering device, a cleaning device, and the like.

Further, the wafers 1 are transferred between the same type equipment groups A, B, C, D by the transfer paths 19a, 19b, 19c, 19d provided for each of the equipment groups A, B, C, D and the carrier transfer path 15. The carrying direction is the wafer carrier jig 6 for storing the wafer 1 by the carrier carrying path 15.
When the wafer reaches the position of the carrier leader 16a, the wafer 1 is directly fed from the outside of the carrier leader 16a and the wafer carrier jig 6.
Is automatically read and it is determined whether or not the same kind of equipment group A should be processed. As a result of the judgment, when the similar equipment group A is to be processed, a plurality of equipment small groups a ₁
… Determine which of a _n should be processed. As a result, when it is to be processed by the same type equipment subgroup a ₁ , the management shelf 18
It is put on the shelf for equipment subgroup a _{1 of} a.

Then, the wafer 1 is taken out from the wafer carrier jig 6 stored in the shelf for the equipment subgroup a ₁ of the management shelf 18a, and the bare wafer 1 is sent to the transfer path 19a and passed through the transfer path 19a. When it reaches the position of the equipment subgroup a ₁ , the wafer 1 is transferred into the equipment subgroup a ₁ by the wafer charger 20 ′.

First, the wafer 1 sent into the equipment subgroup a ₁ is
Microcomputer 3a installed along with a ₁
When the portion shown in FIG. 1 is read by (R _a1 ), the information shown in FIG.
And to the large-scale computer 23 via the modem 22.

In the large-scale computer 23, the manufacturing conditions for the received identification information of the wafer 1 are sent to the microcomputer 3a (R _a1 ) via the reverse route.

The equipment subgroup a ₁ processes the wafer 1 based on the manufacturing conditions sent from the large-scale computer 23, and the processing results and the processing results are calculated by the handheld computer 24.
It is transmitted to 23 and stored in the database 25. In this case, the processing result is the name and date and time of the apparatus that performed the processing, and the processing result is the dimension of the wiring in the case of an etching process, for example.

These pieces of information are collected on a sheet-by-sheet basis, which enables production control and quality control on a sheet-by-sheet basis.

In addition, information collection in the above-mentioned single-wafer unit is for each of the same type equipment groups A, B,
Although they are installed in C and D, they operate in the same manner as described above, and therefore will be omitted from the description of the same type equipment groups B, C, and D below.

After the scold, the wafer 1 was treated completed by the equipment sub-group, a ₁
Is sent to the transfer path 19a by the wafer charger 20 ',
When the wafer 1 reaches the position sent by the original wafer charger 20 through the transfer path 19a, the wafer 1 is inserted into the wafer carrier jig 6 stored in the management shelf 18a by the wafer charger 20 and fixed in close contact therewith. It

Next, the wafer carrier jig 6 is taken out from the management shelf 18a and sent to the carrier transfer path 15, and the carrier transfer path 15
When reaching the carrier leader 16b through the carrier carrier 16b, the carrier leader 16b directly contacts the wafer 1 from outside the wear carrier jig 6.
Is automatically read to determine whether or not the same type equipment group B should be processed. As a result of the judgment, when the equipment group B of the same kind should be processed, a plurality of equipment small groups b ₁ ...
Determine which of b _n should be processed. As a result, when the equipment small group b ₁ is to be processed, it is put on the equipment small group b ₁ shelf of the management shelf 18b.

Then, the wafer 1 is taken out from the wafer carrier jig 6 stored in the shelf for the equipment subgroup b ₁ of the management shelf 18b by the wafer charger 20, and the bare wafer 1 is sent to the transfer path 19b and passed through this transfer path 19b. When the wafer 1 reaches the position of the equipment subgroup b ₁ , the wafer 1 is transferred into the equipment subgroup b ₁ by the wafer charger 20 for processing.

The treatment process in the same kind of equipment group B is, as shown in FIG. 5 in which the photo group B of step 2 on the right side is decomposed and shown on the left side, in step 2-1 a resist is applied to the wafer and then step 2- Exposure is performed at 2. Each time the exposure process is performed, a symbol indicating the product type and the wafer No. and a symbol indicating that the process is completed are provided on the wafer 1.
Is transferred to the first position of. For example, the product type shown in the character string L in FIG. 2 and the symbol indicating the wafer No. are shown in the left half, and the symbol indicating that the exposure process of the photo group B shown in the character string R in FIG. Transfer to the right half of Figure 1. In order to perform this transfer, draw these patterns on a mask or reticle in advance.The reason for transferring not only the symbol indicating the exposure process but also the symbol indicating the product type and wafer No. for each exposure process is This is because the sharpness of the symbol is deteriorated by repeating the photolithography.

After the exposure process is completed in this way, when the wafer 1 proceeds to step 2-4 and undergoes the pragma etching process, the wafer 1 is transferred to the wafer charger 20 '.
When the wafer 1 reaches the position sent by the original wafer charger 20 through the transfer path 19b, the wafer 1 is moved by the wafer charger 20 into the wafer carrier jig 6 stored in the management shelf 18b. It is inserted and fixed tightly.

Then, the wafer carrier jig 6 is taken out from the management shelf 18b and sent to the carrier transfer path 15, and the carrier transfer path 15
When reaching the carrier leader 16c through the wafer carrier jig 16c, the carrier leader 16c directly receives the wafer 1 from the outside of the wafer carrier jig 6.
Is automatically read to determine whether or not the same type of equipment group C should process. As a result of the judgment, when the same kind of equipment group C is to be processed, a plurality of equipment small groups c ₁ ...
Determine which of c _n should be processed. As a result, when it should be processed in facilities subgroup c ₁ is placed in a facility subgroup c ₁ shelf management shelf 18c.

Then, the wafer 1 taken out from the wafer carrier jig 6 stored in the equipment subgroup c ₁ shelf of the management shelf 18c by the wafer charge 20 is sent to the transfer path 19c and passed through the transfer path 19c. When the wafer 1 reaches the position of the equipment sub-group c ₁ , the wafer 1 is transferred into the equipment sub-group c ₁ by the wafer charger 20 ′ for processing.

Then, when the processing in the equipment subgroup c ₁ is completed, the wafer 1
Is transferred to the transfer path 19c by the wafer charger 20 ', and when it reaches the position sent by the original wafer charger 20 through the transfer path 19c, the wafer 1 is transferred to the wafer charger 20.
Thus, the wafer carrier jig 6 stored in the management shelf 18c is inserted and fixed in close contact.

Next, the wafer carrier jig 6 is taken out from the management shelf 18c and sent to the carrier transfer path 15, and the carrier transfer path 15
When reaching the carrier leader 16d through the wafer carrier jig 16d, the carrier leader 16d is directly attached to the wafer 1 from outside the wafer carrier jig 6.
Is automatically read to determine whether or not the same type equipment group D should be processed. As a result of the determination, when the equipment group D of the same kind should be processed, a plurality of equipment small groups d ₁ ...
Determine which of d _n should be processed. As a result, when it should be processed in facilities subgroups d ₁ is placed in a facility subgroup d ₁ shelf management shelf 18d.

Then, the wafer 1 is taken out from the wafer carrier jig 6 stored in the shelf for the equipment subgroup d ₁ of the management shelf 18d by the wafer charger 20, and the bare wafer 1 is sent to the transfer path 19d and passed through the transfer path 19d. When reaching the position of the equipment subgroup 19d, the wafer 1 is sent into the equipment subgroup 19d by the wafer charger 20 'for processing.

Then, when the processing in the equipment subgroup d ₁ is completed, the wafer 1
Is transferred to the transfer path 19d by the wafer charger 20 ', and when it reaches the position sent by the original wafer charger 20 through the transfer path 19d, the wafer 1 is transferred to the wafer charger 20d.
Then, it is inserted into the wafer carrier jig 6 stored in the management shelf 18d, fixed in close contact therewith, and the above operation is repeated again.

In this embodiment, the carrier management shelves 18a, 18b,
The parts 18c, 18d, the transfer paths 19a, 19b, 19c, 19d, and the wafer chargers 20, 20 'are kept in a clean environment.

〔The invention's effect〕

Since the present invention is configured as described above,
Since it is possible to collect data on manufacturing conditions, processing results, and processing results on a sheet-by-sheet basis, it is possible to grasp the status of process progress on a sheet-by-sheet basis, enabling in-process control, and especially for specific ICs. The production period of the product can be shortened.

In addition, since it is possible to control the quality on a sheet-by-sheet basis, it is possible to improve the accuracy of cause estimation in defect analysis and shorten the manufacturing period of adaptive control.

Further, since the correlation between the manufacturing condition and the processing result can be grasped for each individual sheet, the accuracy can be improved by adjusting the equipment.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the position of a single-wafer unit control symbol on a wafer, which is an embodiment of the present invention. FIG. 2 is a diagram explaining a method of assigning a symbol to the single-wafer unit control symbol position shown in FIG. FIGS. 3A and 3B show an example of a wafer carrier jig used in the present invention. FIG. 3A is a perspective view, FIG. 3B is a perspective view showing a carrier body, and FIG. FIG. 4 is a perspective view showing a portion to be processed, and FIG. 4 is an explanatory view showing a production management device of a single-wafer unit which is an embodiment of the present invention, in which (a) is a plan view, (b) is a carrier leader, An enlarged perspective view showing a management shelf and a putter, (c) is an enlarged perspective view showing a wafer charger between a transfer path and a small group of equipment,
FIG. 5 is a flow chart showing the main steps of the MOS memory in the photolithography process. 1 ... wafer, 2 ... orientation flat,
3 ... Symbol, 6 ... Wafer carrier jig, 16 ... Carrier leader, 17 ... Pusher, 18 ... Management shelf, 19 ... Transport path, 20 ... Wafer charger

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sadao Sadao 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi Production Engineering Laboratory, Inc. (72) Haruo Otani 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Production Engineering Laboratory, Hitachi, Ltd. (56) References JP-A-61-284920 (JP, A) SAI-KAI 61-103374 (JP, U)

Claims (2)

(57) [Claims] 1. A semiconductor wafer production control method for arranging a plurality of same-type equipment groups made up of a plurality of same-type equipment and manufacturing semiconductor wafers by repeatedly transporting between the plurality of same-type equipment groups. Each time it is processed, at least an identification code indicating the wafer type, No., and processing step is transferred to the end of the semiconductor wafer that does not affect the product by photolithography, and the transferred identification code is processed. A method for production control of semiconductor wafers, which is read in a process to identify the semiconductor wafers individually. 2. The product type, No., on the surface of the semiconductor wafer.
Is set, and a plurality of symbol areas for displaying symbols representing the processing steps are set for each exposure step corresponding to each processing step.