JP3526129B2 - Progress instruction method and progress instruction device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a progress instructing method and a progress instructing device for instructing an operator how to process a product in a manufacturing line for manufacturing a product such as a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, in a manufacturing line for carrying out a plurality of processing steps for manufacturing a product such as a semiconductor device, after the processing of the product is carried out in each processing step, the processing state of the product is examined to find a defect. If found, the production of the product is stopped and discarded, and a substitute product is newly added to the production line to process the product from the beginning.

[0003]

However, the cause of the defect of the product may not exist in the processing step in which the defect is found, but may exist in the processing step before it. In such a case, by stopping the production of the product at the processing step causing the defect of the product and introducing another product into the manufacturing line, the defect is found from the processing step next to the processing step causing the defect. It is considered that wasteful execution of each process up to the processing process can be canceled, and soaring of the manufacturing cost of the product can be suppressed by the cost required for the processing in the canceled processing process.

However, in the conventional product processing method, since the product processing steps are carried out until a defect is found, it is not possible to suppress the increase in manufacturing cost. Therefore, an object of the present invention is to provide a progress instructing method and a progress instructing device capable of suppressing a rise in the manufacturing cost of a product due to a decrease in yield due to a defect in the product.

[0005]

Progress instruction method according to claim 1, wherein Means for Solving the Problems] is a progress instruction method for processing a product in a production line for implementing a plurality of processing steps, progress indicating device
The yield average value calculating means calculates the yield average value (yield average) from the past processing results of a plurality of products, and in a certain processing step, the yield of the progress instruction device is calculated.
A step factor setting means sets in advance the yield factors affecting the yield of the product Ri, yield of the progress indicating device
A step of the rounding factor influence calculation means is obtained in advance the relationship between the yield of the product and the yield factor from the processing results of the past product, property measurement unit of the progress indicating device with respect to the Ah <br/> Ru products The step of measuring the characteristics related to the yield factor, the expected yield value calculating means of the progress indicating device relates to the relationship between the yield factor and the product yield obtained in advance, and the yield factor related to the certain product. A step of obtaining an expected value of the yield of the certain product (estimated yield) from the measurement result of the characteristic, and the first manufacturing of the progress indicating device.
Based on the expected value of the yield of the certain product, the cost calculation means calculates the first manufacturing cost of the product when the manufacturing of the certain product is continued,

[0006]

[0007]

[Equation 5]

The step of obtaining by the above, and the progress instructing device
The second manufacturing cost calculation means stops the manufacturing of the certain product and instead supplies another product of the same type to the manufacturing line,

[0009]

[Equation 6]

The step of obtaining by the above, and the progress instructing device
The product re-input determination means compares the first manufacturing cost with the second manufacturing cost, and when the first manufacturing cost is lower, continues manufacturing the certain product, If the manufacturing cost of item 2 is lower, a step of instructing that the manufacturing of the certain product is stopped and that another product of the same type is newly added to the manufacturing line instead is provided. Characterize.

According to the above progress instruction method, the manufacturing cost when the manufacturing of the product is stopped and a replacement product is newly introduced into the manufacturing line is lower than the manufacturing cost when the manufacturing of the product is continued. If this is expected, the operator can be instructed to discontinue production of the product and put a new product on the production line. It is possible to cancel the wasteful execution of each process from the next process step of the next process step to the process step in which a defect is found, and only the cost of processing in the canceled process step,
It is possible to suppress a rise in the manufacturing cost of the product.

According to a second aspect of the present invention, there is provided a progress instruction device having a plurality of processing units.
Process products on a manufacturing line that performs physical processing
It is a progress indicator, and is it the past record of processing multiple products?
Yield to obtain the average value of yield (average yield)
Average value calculation means and product yield in a certain process
Yield rate that presets yield factors that affect
Factor setting means, the yield factor and the product yield
The relationship with Mari has been obtained in advance from past product processing results .
Ku and yield factors influence calculation means, before with respect to certain products
Characteristic measuring means for measuring the characteristic relating to the yield factor,
Relationship between the yield factor obtained in advance and the product yield
And the measurement of the characteristics related to the yield factor of the certain product.
And a constant result, the certain step products Tomah Rino expected value (expected
And yield the expected value calculation means for calculating the yield), there the
Based on the expected value of product yield,
If you continue, the first manufacturing cost of the product,

[0013]

[0014]

[Equation 7]

First manufacturing cost calculation means obtained by
Then, the production of the certain product was discontinued and replaced with the same product type.
When other products of
The second manufacturing cost

[0016]

[Equation 8]

Second manufacturing cost calculation means obtained by
And the first manufacturing cost and the second manufacturing cost
In comparison, if the first manufacturing cost is lower,
Will continue to manufacture the certain product, and the second manufacturing cost
If it becomes cheaper, discontinue production of the certain product
Instead, another product of the same product type is newly manufactured and
Characterized in that it e Bei the product cycled judging means for instructing to be introduced into the emissions. According to the above-mentioned progress instruction device, it is expected that the manufacturing cost when the manufacturing of the product is stopped and a substitute product is newly introduced into the manufacturing line is lower than the manufacturing cost when the manufacturing of the product is continued. In this case, the operator can be instructed to discontinue the production of the product and put a new product on the production line. It is possible to cancel wasteful execution of each process from the next process step to the process step in which a defect is found, and it is possible to suppress the soaring of the manufacturing cost of the product by the cost of the process in the canceled process step. .

[0018]

DETAILED DESCRIPTION OF THE INVENTION A progress instruction method according to an embodiment of the present invention will be described below. According to the progress instruction method of the embodiment of the present invention, when a product is processed in a manufacturing line that carries out a plurality of processing steps, the product yield is taken into consideration to continue the product manufacturing or stop the product manufacturing. This is a method of instructing whether to substitute a new product into the manufacturing line at the end of the treatment process, and based on the yield, the manufacturing cost of the product when continuing to manufacture the product and the product manufacturing Calculate the product manufacturing cost when a new product is put into the manufacturing line according to a predetermined formula (described later), and continue manufacturing the product if the manufacturing cost is lower if the product manufacturing continues. , If it is cheaper to discontinue the production of the product and introduce a new substitute product into the production line, we will discontinue the production of the product and introduce a new substitute product into the production line. Give instructions.

In this case, the yield at the time of calculating the manufacturing cost of the product when the manufacturing of the product is continued, the yield factor affecting the yield for each process of the manufacturing line and the relation between the yield and the past product It is obtained in advance from the processing results of step 1, and is obtained as an expected yield from the amount of the yield factor in each process based on the relationship between the amount of the yield factor and the yield ratio. In addition, the yield when calculating the manufacturing cost of a product when the manufacturing of the product is stopped and a replacement product is newly introduced into the manufacturing line is calculated as the yield average from the past processing results of the product.

According to the above progress instruction method, the manufacturing cost when the manufacturing of the product is stopped and a replacement product is newly introduced into the manufacturing line is lower than the manufacturing cost when the manufacturing of the product is continued. If this is expected, the operator can be instructed to discontinue production of the product and put a new product on the production line. It is possible to cancel the wasteful execution of each process from the next process step of the next process step to the process step in which a defect is found, and only the cost of processing in the canceled process step,
It is possible to suppress a rise in the manufacturing cost of the product.

Next, a progress instruction device according to an embodiment of the present invention will be described with reference to FIGS. 1, 2 and 3 by taking a semiconductor device manufacturing line as an example. FIG. 1 is a flowchart showing a process performed by the progress instruction device according to the embodiment. 2A to 2E are schematic process diagrams for explaining a method for manufacturing a semiconductor device. Fig.3 (a)-
(C) is a characteristic diagram for explaining a method of predicting the yield in the gate etching step.

The progress instruction device according to this embodiment is
For carrying out the above-mentioned progress instruction method, that is, for performing a plurality of processing steps, for example, when processing a product in a semiconductor device manufacturing line, in consideration of the product yield, whether to continue manufacturing the product. The manufacturing cost calculation means 101 is used at the end of the processing step to instruct whether the production of the product is stopped and a replacement product is newly added to the production line.
And product re-input determination means 102. Based on the yield, the manufacturing cost calculation means 101 calculates the manufacturing cost of the product when the manufacturing of the product is continued and the manufacturing cost when the manufacturing of the product is stopped and discarded and a replacement product is newly introduced into the manufacturing line. Is calculated according to a predetermined arithmetic expression (described later). The product re-input determination means 102 continues the production of the product, stops the production of the product, and newly substitutes a new product into the production line when the production cost becomes lower if the production of the product is continued. If the manufacturing cost becomes low, the operator is instructed to stop the production of the product, discard it, and put a substitute product in the production line.

Before operating the progress instruction device of this embodiment, the relationship between the yield factor affecting the product yield and the yield in each processing step is obtained for each step from the processing results of the product. There is a need. Here, prior to the description of the relationship between the yield factor and the yield, the semiconductor device manufacturing process will be briefly described. The semiconductor device manufacturing process can be roughly divided into five processes. The manufacturing process of the semiconductor device will be described below with reference to FIG. First, the gate oxide film 2 is attached to the semiconductor substrate 1, and the polysilicon film 3 is applied thereon ((a) gate deposition step). Next, a resist 4 is applied on the polysilicon film 3, exposed and developed, and a gate is patterned ((b) exposure step). Next, gate etching is performed by dry etching to form a gate electrode 5 ((c) etching step). Next, As is ion-implanted to form the source 6 and the drain 7, a transistor is manufactured ((d) source / drain step). Finally, the plurality of transistors are coupled to the Al wirings 8 and 9 by the conductors 10 and 11 (wiring step (e)). A semiconductor device is manufactured through these steps.

The characteristic diagram of FIG. 3 shows the relationship between the yield factor and the yield by measuring the variation of the gate length in the wafer immediately after the etching step in the semiconductor device manufacturing line and taking the relationship between the 3σ and the yield as an example. There is. Figure 3
(A) shows the relationship between the gate length and its frequency, which is 3σ
Is the variation in gate length. FIG. 3B shows the relationship between the gate length variation 3σ and the operating frequency of the LSI. In the figure, the standard value of the product is shown by a broken line. The operating frequency of a semiconductor device such as a transistor increases as the gate length decreases. The large variation in the gate length means that not only those with a small gate length but also a large proportion of those with a large gate length, that is, the operating frequency It means that the ratio of low ones is also large. The LSI is composed of a large number of semiconductor devices, and the operating frequency of the LSI is limited by the operating frequency of the lower semiconductor device. Therefore, the larger the variation in the gate length, the lower the operating frequency of the LSI.

FIG. 3C shows the relationship between the gate length variation 3σ and the yield. From FIG. 3C, when the variation 3σ of the gate length is large, the operating frequency of the LSI becomes low. The higher the operating frequency of an LSI, the better. If the operating frequency is lower than the standard value, the LSI becomes defective and is discarded, so the yield approaches zero. (FIG.3 (c)). The yield factor is not limited to the gate length, but may be the number of dust particles having a certain size or more (for example, a particle size of 0.5 μm or more) existing on the wafer. The yield factor and the yield are related to each other. But I will seek as much as possible.

First, a method of calculating the manufacturing cost performed by the manufacturing cost calculating means 101 will be described. Each time the processing of the product in each process is completed, the yield factor is measured, and the graph of the relationship between the yield factor and the yield in the relevant process (obtained in advance from past product processing results) Ask for yield. Here, a method of obtaining the yield performed by the manufacturing cost calculation means 101 will be described by taking an example immediately after the processing of the gate etching step is completed. First, after the gate etching process is completed, the variation 3σ in the gate length of the transistors in the wafer is obtained (FIG. 3).
(A)). Next, the expected yield is obtained from the relationship between the yield and the gate length variation 3σ which is obtained in advance (FIG. 3C). Next, based on the obtained yield, the manufacturing cost when the manufacturing of the product is continued as it is and the manufacturing cost when the manufacturing of the product is stopped and a substitute product is newly introduced into the manufacturing line are calculated.

An example of the manufacturing cost calculation method by the manufacturing cost calculation means 101 will be described below. First, [Equation 9] is an example of a calculation formula for calculating the manufacturing cost in the manufacturing cost calculation unit 101, and is used when obtaining the manufacturing cost (hereinafter, manufacturing cost 1) when manufacturing the product is continued. To do. Next, [Equation 10] is an example of a calculation formula for similarly calculating the manufacturing cost in the manufacturing cost calculation means 101, which is a case where the manufacturing of a product is stopped and a replacement product is newly introduced into the manufacturing line. It is used when obtaining the cost (hereinafter, manufacturing cost 2).

[0028]

[Equation 9]

[0029]

[Equation 10]

Here, the average yield is the average yield obtained from the past processing results of products. The treatment cost indicates the cost of treatment in each treatment step, for example, the cost of using the device or the cost of the chemical solution used for treating the product. The manufacturing cost calculation means 101 obtains the manufacturing cost 1 and the manufacturing cost 2 by using the above [Equation 9] and the above [Equation 10].

Next, in the product re-input judging means 102, the manufacturing cost 1 calculated by the manufacturing cost calculating means 102
And the manufacturing cost 2 are compared with each other, and it is determined whether to continue manufacturing the product or to stop the manufacturing of the product and newly insert a replacement product into the manufacturing line according to the magnitude relationship therebetween. Notify the operator of the judgment result.

A method for determining whether to continue the production of the product by the product reintroduction determining means 102 or to stop the production of the product and newly introduce a substitute product into the production line will be described below. If (manufacturing cost 2)> (manufacturing cost 1),
Since it means that the manufacturing cost is cheaper when the product is manufactured, the product is manufactured.

In the case of (manufacturing cost 1)> (manufacturing cost 2), it means that the manufacturing cost will be lower if the manufacturing of the product is stopped and a substitute product is newly introduced into the manufacturing line. Discontinue the production of the products that have been processed up to now and discard them, and put new substitute products on the production line. As described above, in each process step of manufacturing a product, the manufacturing cost calculation means 101 is used to stop the manufacturing cost and the manufacturing cost when the manufacturing of the product is continued, and a replacement product is newly manufactured on the manufacturing line. If the manufacturing cost is lower if the product re-input determination means 102 stops manufacturing the product and puts a substitute product on the manufacturing line, the processing of the product is performed. The operator is instructed to stop and newly insert a substitute product into the production line.

The formula for calculating the manufacturing cost in the progress indicating device according to the embodiment of the present invention is represented by [Equation 9].
Although the above [Equation 10] is used, another calculation formula may be used as long as the manufacturing cost is set to be higher as the yield is lower.

[0035]

According to the progress instructing method and the progress instructing apparatus of the present invention, in each processing step for processing a product, the manufacturing cost and the processing of the product when the manufacturing of the product is continued in consideration of the yield are stopped. To obtain the manufacturing cost when a substitute product is newly introduced into the manufacturing line, and to instruct the operator how to process the product with the lower manufacturing cost, and the operator should perform the processing in accordance with this instruction. This makes it possible to cancel the wasteful execution of each process from the process step following the process step that causes the defect to the process step in which the defect is found, and the cost of the process in the canceled process step It is possible to suppress a rise in manufacturing cost.

[Brief description of drawings]

FIG. 1 is a flowchart showing a process performed by a progress instruction device according to an embodiment of the present invention.

FIG. 2 is a schematic process diagram for explaining a method for manufacturing a semiconductor device.

3A and 3B are characteristic diagrams for explaining a method of predicting a yield in a gate etching step, in which FIG. 3A shows the relationship between the gate length and the frequency, and FIG. 3B shows the relationship between the variation in the gate length and the operating frequency. (C) shows the relationship between the variation in gate length and the yield.

[Explanation of symbols]

101 Manufacturing cost calculation means 102 Product re-input judging means

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G05B 19/418 B23Q 41/08 G06F 17/60 H01L 21/02

Claims (2)

(57) [Claims] 1. A progress instructing method for processing a product in a manufacturing line that executes a plurality of processing steps, wherein a yield average value calculating means of a progress instructing device calculates an average yield value from past processing results of a plurality of products. And a step of presetting a yield factor in which a yield factor setting means of the progress indicating device affects the yield of the product in a certain processing step, and a yield factor influence degree calculating means of the progress indicating device calculates the yield. A step of preliminarily obtaining a relationship between a factor and a yield of the product from past product processing results; a step of measuring a characteristic relating to the yield factor for a product having characteristic measuring means of the progress indicator; The yield expected value calculation means of the pointing device relates to the relationship between the yield factor and the product yield obtained in advance and the certain product. From the measurement result of the characteristics related to the yield factor, a step of obtaining an expected value of the yield of the certain product, and the first manufacturing cost calculation means of the progress instruction device is based on the expected value of the yield of the certain product. The first manufacturing cost of the product when the product is continuously manufactured is And the second production cost calculation means of the progress instruction device stops the production of the certain product, and instead another product of the same type is newly introduced into the production line. The manufacturing cost is And the product re-input determination means of the progress instruction device compares the first manufacturing cost with the second manufacturing cost,
If the manufacturing cost is lower, the certain product is continued to be manufactured. If the second manufacturing cost is lower, the certain product is stopped and the same product is replaced. And a step of instructing that another product of the above is newly introduced into the manufacturing line. 2. A progress instructing device for processing a product in a manufacturing line that carries out a plurality of processing steps, and a yield average value calculating means for obtaining an average yield value from past processing results of a plurality of products. In the processing step, a yield factor setting unit that presets a yield factor that affects the yield of the product, and a yield factor influence degree that is obtained in advance from the past product processing results of the relation between the yield factor and the yield of the product. Calculating means, characteristic measuring means for measuring the characteristics related to the yield factor for a certain product, the relationship between the yield factor and the product yield obtained in advance, and from the measurement result of the characteristics related to the yield factor for the certain product An expected yield value calculating unit for obtaining an expected yield value of the certain product, and an expected yield value of the certain product Based on the first manufacturing cost of the product in the case of continued production of the products, Equation 3] And a second manufacturing cost when the manufacturing of a certain product is stopped and another product of the same type is newly introduced into the manufacturing line.
The manufacturing cost of By comparing the second manufacturing cost with the second manufacturing cost calculating means obtained by the above, and if the first manufacturing cost is lower, the manufacturing of the certain product is continued. If the second manufacturing cost is lower, the product re-instruction is instructed to discontinue the manufacturing of the certain product and instead to newly supply the other product of the same type to the manufacturing line. A progress instruction device comprising: a determination unit.