WO2010112614A1

WO2010112614A1 - Method and device for identifying object and for tracking objects in a production process

Info

Publication number: WO2010112614A1
Application number: PCT/EP2010/054503
Authority: WO
Inventors: Edgar RÜTH; Wolfgang Becker
Original assignee: Singulus Technologies Ag
Priority date: 2009-04-03
Filing date: 2010-04-06
Publication date: 2010-10-07
Also published as: EP2414111A1

Abstract

An object (1) is identified based on the unique, characteristic, optical properties (10) before the object is processed in a facility (3). In addition, a unique indicator is assigned to the object (1). All production data and process parameters for all facilities (3) through which the object (1) passes are stored together with the indicator in an electronic data processing device (6). After the object (1) has passed through a facility (3), the object (1) can be identified again based on the unique, characteristic, optical properties (10) of the object. Thus it can be examined whether the system for tracking the object (1) within a production facility (3) functions without errors. Alternatively, the new identification can also be used to assign a new indicator to an object (1) for which the unique, characteristic, optical properties (10) have changed during the production process.

Description

Method and device for identifying objects and for tracking objects in a production process

The present invention relates to a method and a device for identifying objects, wherein these are each assigned a unique identifier. With the help of this indicator, the objects can be tracked in a production process and the relevant data of each process step and further process steps are stored together with the indicator.

In a production process, an item goes through many different process steps. At each process step, a system is run through. To enable identification of the item, the item is marked. There are several ways to mark the item (e.g., writing with a special pen, carving or notching with a sharp object, etc.). The item is changed by marking. With a marker, the object can be tracked throughout the editing process, as it is clearly marked by the marker. Identification at various points in the production process is thus possible. Individual parameters and / or production data from different process steps can also be assigned to a marked object. The marking must be firmly connected to the object, so that it can not come to a damage of the marking. The marking must remain on the object during the production process and the readability of the mark must not deteriorate during a process step.

The object of the present invention is to provide a method and a device with which the identification of an object and the assignment of a license plate to this object can be reliably ensured. In addition, a reliable system for tracking and process data collection of the object in the production process. This object of the invention is achieved with the features of the claims.

The invention is based on the basic idea of identifying the object on the basis of its unique, characteristic, optical features, so that a clear identification can be assigned to the object. The identification of the article is e.g. based on the unique structure of its surface. This eliminates the additional application of an identifier on the object. The object does not have to be changed by an additional marking, so that it can also not affect the legibility of the marking in the identification of the object. This provides a reliable system for identification, product tracking and process data collection.

With means for identifying the object, the object is identified by its unique, characteristic, optical features. The identification of the article may e.g. on the basis of a recorded image of the object. The identification can be carried out before or in a plant. An electronic data processing device (e.g., a host computer) associates the article with a unique identifier.

During a process step within an installation, the respective location of the object is tracked and the object is managed by a facility. In addition, during execution of the process step in the plant, the relevant process parameters and / or production data of the object are stored in the electronic data processing device together with the unique identifier.

After the item has passed through the system, the item may be re-identified with another means for identifying the item. This can be used to check whether the tracking of the object within the system is faulty. Alternatively, the item may be assigned a new tag if the unique, characteristic, optical features have changed during a process step. In the production process, the item can go through several systems in succession. At each installation, identification, tracking and management and storage of process parameters and / or production data under the unique identifier of the item is possible. In addition, a re-identification of the item may take place after each pass through a facility. This checks whether the tracking of the object within the respective system is error-free. Between the individual plants, the object can be stored.

The inventive method and device for identifying objects with unique, characteristic, optical features is well suited for wafers. In particular, the wafer may be a PV wafer (PV: photovoltaic) based on polycrystalline silicon.

The invention will be explained in more detail below with reference to the drawings. Show it:

Fig. 1 shows a schematic representation of the surface of a wafer;

Fig. 2 shows a schematic representation of an apparatus for identifying and tracking an article (wafer) with unique, characteristic, optical features.

In Fig. 1, an object 1 is shown, the surface of which has unique, characteristic, optical features 10. In general, all unique, unique, optical features 10 of an item 1 can be used for unique identification. This object 1 is, for example, a wafer 1, in particular a square wafer 1 with a side length of, for example, 100-160 mm and a thickness of approximately 0.05-0.25 mm. The wafer 1 shown in FIG. 1 is manufactured on the basis of polycrystalline silicon. These wafers 1 are particularly suitable for photovoltaic (PV); Such wafers 1 are also referred to as PV wafers 1. The structure of the surface is unique for each wafer 1, similar to the fingerprint of a human. Hereinafter, an embodiment of the present invention for such a wafer 1 will be described. Fig. 2 shows an apparatus for identifying and tracking a wafer 1 comprising a plurality of machines or processing stations 3-1, 3-2, ... 3-n, a plurality of devices 2-1, 2-2, ... 2-n and 2 for identifying the wafer 1, a plurality of memory devices 4-1 and 4-2 for storing the wafer between the devices 3-1, 3-2, ... 3-n, a final memory device 4-n, a plurality of each Annex belonging data processing facilities 5-1, 5-2, ... 5-n and a central data processing device 6 has.

The structure of the wafer 1 with unique, unique, optical features 10 is formed prior to the first production step, i. before or in the first system 3-1, with a device 2-1 for identifying the wafer 1 detected. In particular, this device 2-1 for identifying the wafer 1 may be a camera which takes an image of the surface of the wafer 1. The picture, i. the electronic data of the image are transmitted to the data processing device 5-1 of the first system 3-1. The data reach the central data processing device 6 via the data processing device 5-1 of the first system 3-1. The data processing device 6 can be designed as a host computer 6. The host computer 6 assigns the unique structure of the surface of the wafer 1 a unique name (label) and stores them in a database. Such a unique designation may e.g. be a unique number. Subsequently, the processing of the wafer 1 in the first Appendix 3-1. The processing of the wafer 1 in the first system 3-1 represents the first process step in the production process. The process parameters and the production data of the wafer 1 for the first system 3-1, which are to be stored during the first process step, are transmitted via the data processing device 5 -1 of the first system 3-1 transmitted to the host computer 6. In the host computer 6, the process parameters and the production data of the wafer 1 are stored under the unique number assigned to the wafer.

At the end of the first Annex 3-1 it is possible to check the device for tracking and managing the object 1 within Appendix 3-1. This is done by taking a picture of the structure of the surface of the wafer 1 with another camera 2-2 at the end of the first system 3.1. This picture will compared with the data stored in the host computer 6. This can ensure that the device for tracking and managing the item 1 within the entire system 3 works properly.

Alternatively, a re-identification of a wafer 1 according to an appendix 3-1, 3- 2,... 3-n can also be used to associate the wafer 1 with updated unique, characteristic, optical features. This may be required if the surface texture of the wafer changes in a plant 3-1, 3-2, ... 3-n. Such a change may occur, for example, in a coating process. In this case, the tag, which has been assigned to the item due to the original or formerly unique optical features, is assigned the changed (updated) unique, optical features in order to subsequently identify the item. As a result, in the following processing stations, the process parameters and / or production data to be newly stored are correlated with the updated one-time characteristics and are thus again assigned to the associated identifier of the object.

The wafer 1, after passing through a plant, e.g. Appendix 3-1, directly to the next Appendix 3-2 (for example, a processing station). The transfer can be done both directly and automatically by hand. In addition, there is the possibility of storing (buffering) the wafer 1 in a memory device 4-1 between two devices 3-1 and 3-2. In principle, any number of systems can be used in the method according to the invention and in the device according to the invention. In the host computer 6, the process parameters and / or the production data for the wafer 1 in the database are supplemented for each additional installation 3-1, 3-2,... 3-n under the unique identifier of the object. Thus, the wafer 1 during the process step in the respective system 3-1, 3-2, ... 3-n all relevant data assigned, so that at the end of the entire production history is displayed. With the help of either before or after the last memory unit 4-n arranged camera 2, the processed object 1 is subsequently identified and thus checked for the correct assignment.

According to the invention, therefore, with the aid of a camera 2-1, 2-2,... 2-n, 2, the wafer 1 is identified on the basis of its surface structure and this characteristic is identified. (eg a number). A reliable system for identification and process data collection is created from a combination of camera surveillance and tracking of the wafer 1 in a facility (with means for tracking and management of the wafer 1).

Claims

claims

A method of identifying an article (1) characterized by a) determining unique, characteristic, optical features (10) of the article (1) and b) storing the identified features (10) as indicia of the article (1).

2. The method of claim 1, wherein as a unique, characteristic, optical feature (10), the optical surface structure of the article (1) is determined.

3. The method of claim 2, wherein the optical surface structure is detected as an image by a camera (2).

A method of tracking an article (1) in a production process with one or more process steps by: a) applying the identification method of any one of claims 1 to 3 and b) associating and storing process parameters and / or production data for the article (1) in the respective process step as process step data to the stored identifier of the object.

5. The method of claim 4, wherein in the case of changing, unique, characteristic, optical features during a process step, the changed unique, characteristic optical features after the process step form the current characteristic of the object.

6. The method of claim 4 or 5, wherein is checked with a re-identification of the substrate on the basis of its unique, characteristic, optical features (10) after passing through a system (3), whether the tracking within a system (3) during a process step is faulty.

7. The method of claim 4, 5 or 6, wherein the article (1) can be stored between the individual process steps.

8. The method according to any one of claims 4 to 7, wherein the production data and the process parameters are stored in an electronic data processing device (6) associated with the respective license plate.

9. The method according to any one of claims 1 to 8, wherein the article (1) is a wafer.

10. The method of claim 9, wherein the wafer is a polycrystalline silicon based photovoltaic (PV) wafer.

Device for identifying an article (1) according to claim 1, 2 or 3, optionally for tracking the article (1) according to any one of claims 4 to 10, comprising: a camera (2) for detecting and identifying the article (1) on the basis of unique, characteristic, optical features (10) of the object (1) before or in a processing installation (3); an electronic data processing device (6) for storing the unique, characteristic, optical features (10) of the object (1) in digital form and for assigning a mark for the object (1); and means for tracking and managing the item (1) within the processing plant (3).