JP3175686B2 - Process flow check system and process flow check method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process flow check system and a process flow check method, and more particularly to processing of a wide variety of semiconductor wafers having a plurality of manufacturing steps, different process orders and different processing conditions. TECHNICAL FIELD The present invention relates to a system and a method for checking a manufacturing process flow (hereinafter, referred to as a process flow) in a multi-product variable-quantity manufacturing line for simultaneously manufacturing products.

[0002]

2. Description of the Related Art Conventionally, techniques relating to various manufacturing systems have been proposed.

As an example, a process procedure system disclosed in Japanese Patent Application Laid-Open No. 9-128447 will be described with reference to FIG.

A process flow created by a manufacturing process information creating section 71 for creating a process flow and an inferred result state data storage database section 76 storing the initial wafer state of the process flow are used to input the initial wafer state into a manufacturing process information input section 72. To enter.

The information from the manufacturing process information input section 72 is sent to an inference control section 73, and the inference control section 73 converts the process flow information into a first inference section 74A and a second inference section 74B.
To the inference unit 74 having

The inference unit 74 includes a knowledge base unit 75A for dividing the process flow into several wafer states, and a knowledge base unit 75B for determining the validity of the process flow in a certain wafer state. Base storage unit 7
The inference is performed on the basis of No. 5 and the result is output to the inference result state data output unit 77 which outputs the inference result from the inference control unit 73, and is stored in the inference result state data storage database unit 76.

[0007]

In a multi-variable production line having a plurality of manufacturing processes, when a plurality of lots sharing one process flow exist in the line, some of the lots are There is a case where the process flow of a lot is changed, or a case where one lot is divided to have a plurality of process flows.

However, in the case of the above-described process procedure check system, a system for performing a check from an intermediate process is effective when the entire process flow is changed, but the process flow is changed or divided in lot units. In this case, it is not clear how to distinguish the process flow from other lots and the change process flow and how to check the change, so that it is not possible to check when changing or dividing a lot. Therefore, an object of the present invention is to clarify the current wafer state for each of a plurality of lots sharing one process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing processes, and to change the process flow for each lot. An object of the present invention is to provide a process flow check system and a process flow check method that enable anyone to easily and accurately check the validity of a process flow when performing division.

[0009]

A feature of the present invention is to provide a system for checking a process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing processes, which has a function of providing work end information of a lot up to a previous process. Lot status flag based on lot operation end report information means and process flow information up to the previous process (software symbol / code)
The process flow check system includes a flag knowledge unit having knowledge indicating the following, a flag instruction unit having a function of designating a flag in process flow information, and a host computer storing lot information having flag information. Here, the lot is a lot of the semiconductor wafer, and the flag knowledge unit may have knowledge indicating a flag indicating a state of the front and back surfaces of the semiconductor wafer.

Another feature of the present invention is that in a system for checking a process flow in a multi-variable variable-volume manufacturing line having a plurality of manufacturing processes, a host computer for storing lot information having flag information indicating a lot state is provided. , A process flow change information section having a function of providing process flow change instruction information to lot information, and a changed lot process flow creation function having a function of creating a lot change process flow based on information from the process flow change information section A process flow knowledge unit having process flow correct / incorrect information for a flag of a lot; a process flow determining unit having a function of determining consistency between the process flow knowledge unit and the changed lot process flow; A process flow check system including a result output unit having a function of outputting a result in the determination unit. . Here, it is preferable that the process flow change instruction information from the process flow change information section includes division instruction information, flow change information, or condition change information. The lot is a lot of semiconductor wafer,
The flag information has a flag indicating the state of the front and back surfaces of the semiconductor wafer, and the process flow knowledge section can have knowledge of the front and back surfaces of the semiconductor wafer and knowledge of flag / process flow matching.

Another feature of the present invention is that in a method for checking a process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing steps, lot information having flag information indicating a state of a predetermined item of each lot is provided. Is stored in the host computer, the process flow change instruction information is provided to the lot information, the process flow is changed according to the process flow change instruction information, and this is compared with the process flow correctness information for the flag of the lot. Then, there is a process flow check method for determining whether the change instruction information is appropriate or inappropriate. Here, the process flow change instruction information preferably includes division instruction information, flow change information, or condition change information. The lot is a lot of the semiconductor wafer, the flag information has a flag indicating the state of the front and back surfaces of the semiconductor wafer, and the correct / incorrect information of the process flow includes the knowledge of the front and back surfaces of the semiconductor wafer and the knowledge of the flag / process flow matching. By comparing the knowledge of the front and back surfaces of the semiconductor wafer with the flags of the changed process, the change instruction information is matched with the correct / incorrect information by the process flow matching knowledge and is appropriate, or the matching is not performed. You can determine if it is appropriate.

According to the present invention, for example, in the case of processing and manufacturing a semiconductor wafer, it is possible to provide a flag for the state of the front and back surfaces of the semiconductor wafer at the end of the work for each lot. Therefore, it is possible to always know the latest semiconductor wafer state for each lot.

Further, it is possible to check from an intermediate process using the front and back surface state flags provided for each lot. For this reason, it is possible to check the division / change process flow for each lot.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of an entire system according to an embodiment of the present invention.

Lot work end report information means 1 for providing work end information of lots up to the previous process, and knowledge for setting a flag with process flow information 2A up to the previous process.
That is, a software-like symbol that can identify each lot based on the process flow information 2A up to the previous process.
There is provided a flag knowledge unit 2 capable of assigning a code to each lot.

If the object to be manufactured is a semiconductor wafer, the flag knowledge unit 2 is provided with wafer front and back surface knowledge 2B for classifying the process flow information 2A into the front and back surfaces of the semiconductor wafer and setting a flag. I have.

Further, a flag instruction unit 3 for instructing to set a flag on the process flow information is provided, and a host computer 4 for storing lot information 4A which is flagged process flow information is provided.

Further, the lot information having the flag information stored in the host computer 4 is provided with division instruction information 5A for dividing a lot, process flow change information 5B for changing a process flow, and condition change information 5C for changing a processing condition. A process flow change information section 5 is provided, and a changed lot process flow creation section 6 for creating a lot change process flow based on information from the process flow change information section 5 is provided.

Further, there is provided a process flow knowledge section 7 having information on correct / incorrect of a process flow for changing a flag included in the lot information. The process flow knowledge section 7 has a flag / process flow matching knowledge 7B indicating a standard / criterion that the process changed by the flag should originally be such a process. Is a semiconductor wafer, it further has wafer front / back surface flag knowledge 7A for classifying the matching knowledge into the front and back surfaces of the semiconductor wafer.

A process flow determining unit 8 for determining consistency between the reference information from the process flow knowledge unit 7 and the change information from the changed lot process flow creating unit 6 is provided, and outputs a determination result in the process flow determining unit 8. A result output unit 9 is provided.

Next, the operation of the embodiment will be described with reference to FIGS.

FIG. 2 is a flowchart showing a method for setting a flag after the work of the preceding process of the lot is completed.

When the lot operation end report information means reports the end of the lot operation up to the previous process, the information on the end of the lot operation is sent to the flag indicating section (step 21).

Based on the information from the flag knowledge section consisting of the process flow information and the knowledge information on the front and back surfaces of the wafer, the assignment of the wafer state flag after the end of the lot operation is determined by the flag instruction section (step 22).

Then, the flagged lot information is stored in the host computer (step 23). FIG.
9 is a flowchart showing a method for checking a process flow change of a lot.

The division instruction information, flow change information or condition change information is sent from the process flow change information section to the lot information in the host computer for the lot (step 31).

Next, a changed lot process flow is created for the corresponding lot (step 32).

The changed lot process flow is sent to the process flow judging section (step 33), and is made up of knowledge of the front and back surfaces of the wafer having the correct / incorrect information of the process flow for the flag of the lot and the knowledge of the flag / process flow matching. Based on the information of the process flow knowledge unit, the validity of the changed process flow is determined by the process flow determination unit (step 34).

The result of this determination is output (step 3
5). Here, as a result of the determination, if the determination is OK, the change of the lot is completed (step 36). On the other hand, if the judgment result is NG, a changed lot process flow is created again and the same judgment and inference is repeated (step 37).

Next, an embodiment will be described with reference to FIGS.

From the manufacturing conditions up to the previous process and the manufacturing equipment used, the semiconductor wafer of lot A has heavy metal on the surface,
The presence of heavy metal on the back side also indicates that the semiconductor wafer of Lot B has heavy metal on the front side and no heavy metal on the back side.
It is known from the process flow information having the wafer front and back surface information of the flag knowledge section that the semiconductor wafer of the lot C has no heavy metal on the front surface and no heavy metal on the back surface. This process flow information is shown in a table in FIG.

Therefore, the surface of the semiconductor wafer is F (F
ront), B (Back) on the back side, P (Presence) when there is heavy metal, and A (Absen) when there is no heavy metal
Assuming that the flag ce) is used, a flag FP with heavy metal is set on the front surface of the semiconductor wafer of lot A, and a flag BP with heavy metal is set on the back surface. A flag FP with heavy metal is set on the front surface of the semiconductor wafer of the lot B, and a flag BA without heavy metal is set on the back surface. A flag FA without heavy metal is set on the front surface of the semiconductor wafer of lot C, and a flag BA without heavy metal is set on the back surface.

The fact that the flag is set as described above is a soft matter.
Is stored in the host computer as a part of the lot information.

When stripping is performed immediately after the selective etching step, there is a case where it is necessary to perform acid stripping for heavy metals depending on the presence or absence of the heavy metal on the front and back surfaces, and a case where it is not necessary.

Therefore, in the process flow knowledge section, acid stripping treatment for heavy metal is performed on a lot having a heavy metal on one of the front and back surfaces, and both lots having a flag with no heavy metal on the front surface and the back surface are processed. He has the knowledge of not performing acid stripping treatment for heavy metals.

Therefore, as shown in FIG. 6, the information from the process flow change information section is divided into three routes, and the first route 6 having a peeling means 61 for performing an acid peeling treatment for heavy metals.
2, the lot A flows through the second route 64 having the stripping means 61 for performing the acid stripping process for heavy metals, and the lot C flows into the third route 65 without performing the acid stripping process for heavy metals. If it is the change information, the process flow determination unit determines that the change information matches the knowledge of the process flow knowledge unit, that is, the correct processing flow procedure in conformity with the correct standard technology, and outputs a result of OK from the result output unit. It is output, and it is determined that the process flow procedure to which the change information from the process flow change information section is added is a correct procedure.
Then, actual wafer processing is performed according to this process flow procedure. Thereafter, if necessary, the lots are merged and transferred to the next process.

Alternatively, it is divided into two routes, a route having a stripping means for performing the acid stripping treatment for heavy metals, and a route not performing the acid stripping process for heavy metals, so that lot A and lot B flow in the former and lot C flows in the latter. Also, in the case of the change information, the process flow determining unit matches the change information with the knowledge of the process flow knowledge unit, determines that the process flow is correct, and outputs an OK result from the result output unit.

However, the change information from the process flow change information section is not divided, the acid stripping process for heavy metals is an organic acid stripping process, If the stripping process is not performed, or if the acid stripping process for heavy metals is performed without the presence of heavy metals, N is not consistent with the knowledge of the process flow knowledge section.
As G, the feedback is performed as shown in FIG. 3, another change information is sent from the process flow change information section to the lot information, and it is checked again whether this other information matches the knowledge of the process flow knowledge section. .

[0039]

A first effect of the present invention is that since a lot can be individually flagged and checked, a check for individual change of a lot can be normally and accurately performed. As a second effect, since the latest state flag is set for each lot, when the process flow of all the same process flow lots is changed, the validity of the change at the current in-process position of the lot is determined. Usually, it can be done accurately.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an entire system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a flow for setting a flag after completion of a work in a preceding process of a lot according to the embodiment of the present invention.

FIG. 3 is a diagram showing a flow of a check method of a process flow change of a lot according to the embodiment of the present invention.

FIG. 4 is a diagram showing process flow information according to one embodiment of the present invention.

FIG. 5 is a diagram showing flag information according to an embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a changing step according to an embodiment of the present invention.

FIG. 7 is a diagram showing a conventional technique.

[Explanation of symbols]

 1 Lot work completion report information means 2 Flag knowledge part 2A Process flow information 2B Wafer front and back surface knowledge 3 Flag instruction part 4 Host computer 4A Lot information 5 Process flow change information part 5A Division instruction information 5B Flow change information 5C Condition change information 6 Change Lot process flow creation unit 7 Process flow knowledge unit 7A Wafer front / back surface flag knowledge 7B Flag / process flow matching knowledge 8 Process flow determination unit 9 Result output unit 21 to 23 Step 31 to 37 Step 61 Stripping means for performing acid stripping processing for heavy metals 62 first route 64 second route 65 third route 71 manufacturing process information creating unit 72 manufacturing process information input unit 73 inference control unit 74 inference unit 74A first inference unit 74B second inference unit 75 knowledge base storage Part 75A Coloring knowledge base part 75B State determination knowledge base Scan unit 76 inference result status data storage database unit 77 inference result status data output unit

Claims (8)

(57) [Claims] In a system for checking a manufacturing process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing processes, a lot work end report information means having a function of providing lot work end information up to a previous process; A flag knowledge unit having knowledge indicating a flag indicating a state of a lot according to manufacturing process flow information up to a process, a flag indicating unit having a function of indicating a flag in the manufacturing process flow information, and a lot including the flag information A process flow check system comprising: a host computer for storing information. 2. The process according to claim 1, wherein the lot is a lot of semiconductor wafers, and the flag knowledge unit has knowledge indicating a flag indicating a state of the front and back surfaces of the semiconductor wafer. Flow check system. 3. A system for checking a manufacturing process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing processes, comprising: a host computer for storing lot information having flag information indicating a lot state; A process flow change information unit having a function of providing change instruction information of a manufacturing process flow, and a changed lot process flow creating unit having a function of creating a lot change process flow based on information from the process flow change information unit. A process flow knowledge unit having correct / incorrect information of a process flow with respect to a flag held by a lot, a process flow determining unit having a function of determining consistency between the process flow knowledge unit and the changed lot process flow, A result output unit having a function of outputting a result in the flow determination unit. Low check system. 4. The process flow according to claim 3, wherein the change instruction information of the manufacturing process flow from the process flow change information section includes division instruction information, flow change information, or condition change information. Check system. 5. The lot is a lot of semiconductor wafers, the flag information has a flag indicating a state of the front and back surfaces of the semiconductor wafer, and the process flow knowledge part has a front and back surface flag of the semiconductor wafer. 5. The process flow check system according to claim 3, wherein said process flow check system has knowledge of a flag and a process flow. 6. A method for checking a manufacturing process flow in a multi-variable variable-quantity manufacturing line having a plurality of manufacturing processes, wherein lot information having flag information indicating a state of a predetermined item of each lot is stored in a host computer. Provide the manufacturing process flow change instruction information to the lot information, change the process flow according to the manufacturing process flow change instruction information, and compare this with the correct / incorrect information of the manufacturing process flow for the flag of the lot. And a step for judging whether the change instruction information is appropriate or inappropriate. 7. The change instruction information of the manufacturing process flow,
7. The process flow check method according to claim 6, further comprising division instruction information, flow change information, or condition change information. 8. The lot is a lot of semiconductor wafers, the flag information includes a flag indicating a state of the front and back surfaces of the semiconductor wafer, and the correct / incorrect information of the manufacturing process flow is a knowledge of front and back surface flags of the semiconductor wafer. And the flag / process flow matching knowledge is compared. The semiconductor wafer front / back surface flag knowledge is compared with the changed process flag, and the change instruction information is matched with the correct / wrong information by the process flow matching knowledge. 8. The process flow check method according to claim 6, wherein it is determined whether the process flow is appropriate or unmatched and inappropriate.