JP3862322B2 - Semiconductor device manufacturing system and semiconductor device manufacturing method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor device manufacturing system and a semiconductor device manufacturing method using the same, and more specifically, a semiconductor device manufacturing system for detecting foreign matter during a semiconductor wafer manufacturing process and a semiconductor device using the same. It relates to the manufacturing method.
[0002]
[Prior art]
FIG. 15 is a schematic view showing an etching apparatus which is one of conventional semiconductor wafer manufacturing apparatuses. Referring to FIG. 15, a conventional etching apparatus 100 includes a vacuum chamber 101 that performs an etching process, and a load lock chamber 102 that is used when wafers 104 and 105 are carried in and out. A pair of electrodes 107 and 108 facing each other are installed in the vacuum chamber 101. The electrode 107 is grounded, and the high-frequency power source 103 is connected to the electrode 108. Further, an etching gas supply device 106 for supplying an etching gas is connected to the vacuum chamber 101.
[0003]
An etching process is indispensable in the method of manufacturing the semiconductor wafers 104 and 105. When the etching apparatus 100 is used, a semiconductor material gas (etching gas) is introduced into the vacuum chamber 101. A high frequency output is applied between the electrodes 108 and 107 by the high frequency power source 103 to cause plasma discharge to form gas plasma. Etching is performed by this gas plasma.
[0004]
Recently, micropatterning has progressed, and it is becoming impossible to process using only conventional dry etching techniques. Therefore, conventionally, it has been proposed to use a depositing (depositing) gas that protects the etching sidewall from a gas only for etching. By making such a deposition gas into gas plasma, etching can be performed while protecting the side wall of the object to be etched.
[0005]
[Problems to be solved by the invention]
However, in the method using the depositing gas as the etching gas as described above, deposits of the depositing gas being etched are accumulated on the semiconductor wafer, which is an object to be etched, and becomes a foreign substance. The inconvenience of lowering the yield (non-defective product rate) occurred. Conventionally, in order to eliminate such inconvenience, as shown in FIG. 15, the semiconductor wafer 105 in the manufacturing process in which etching is actually performed is once carried out of the etching apparatus 100 and foreign matter inspection is performed. Based on the result of the foreign matter inspection, processing is performed by a method such as cleaning the etching chamber 101, cleaning other portions, or replacing the electrodes 107 and 108 in accordance with the number of foreign matters. However, the criteria for determining when the number of foreign matters is to be cleaned and when the number of foreign matters is to be used for cleaning the vacuum chamber 101 or replacing the electrodes 107 and 108 are all determined empirically. Therefore, it has been difficult to perform appropriate cleaning. In other words, in the past, the standard of how much foreign matter should be cleaned is ambiguous, and the standard of how much foreign matter should be cleaned and how much cleaning should be done is also ambiguous. It was difficult to perform proper cleaning. As a result, cleaning may be performed unnecessarily. In this case, there is a problem that the operating rate of the apparatus is lowered. In addition, there is a disadvantage that the device that originally needs to be cleaned is not cleaned. In this case, the defective rate of the finished device is increased and it is difficult to improve the yield. In addition, foreign matters were generated in processes other than the etching process, but in this case as well, there was a problem that the standard was ambiguous as described above.
[0006]
The present invention has been made to solve the above-described problems, and one object of the present invention is a semiconductor capable of improving yield (non-defective product rate) without reducing the operation rate of the apparatus. An apparatus manufacturing system and a semiconductor device manufacturing method using the same.
[0007]
Another object of the present invention is to provide a semiconductor device manufacturing system and a semiconductor device manufacturing method using the same that can perform appropriate cleaning of the manufacturing apparatus corresponding to each manufacturing process. .
[0008]
[Means for Solving the Problems]
According to another aspect of the present invention, there is provided a semiconductor device manufacturing system including collective management means and discrimination means. The collective management means is for centrally managing data on foreign matters in each process during the manufacturing process of the semiconductor wafer. The discriminating means is for discriminating a process to be cleaned based on data from the collective management means. Such collective management means and determination means are constituted by, for example, a host computer. In this way, by centrally managing data related to foreign matter during the manufacture of semiconductor wafers, the relationship between the data related to foreign matter in each process and the product failure rate can be easily analyzed. It is possible to grasp the process that affects. Accordingly, the defect rate can be more effectively reduced by performing cleaning while intensively managing the number of foreign matters in the process. In addition, the number of cleanings can be reduced in a process that does not significantly affect the defective rate, and as a result, the yield can be improved without reducing the operating rate.
[0009]
The semiconductor device manufacturing system according to a second aspect includes a manufacturing apparatus and an inspection apparatus corresponding to each process in addition to the configuration of the first aspect, and data relating to foreign matters is online from the manufacturing apparatus and the inspection apparatus to a collective management means. Configured to transmit on.
[0010]
According to a third aspect of the present invention, there is provided a semiconductor device manufacturing system further including a manufacturing apparatus corresponding to each step in the configuration of the first aspect, wherein the manufacturing apparatus detects foreign matter in the manufacturing apparatus. Configure to include.
[0011]
According to a fourth aspect of the present invention, there is provided a semiconductor device manufacturing system including a manufacturing apparatus corresponding to each step in the configuration of the first aspect, wherein the manufacturing apparatus includes cleaning means for cleaning the inside of the manufacturing apparatus. Configure to include.
[0012]
6. The semiconductor device manufacturing system according to claim 5, wherein the cleaning means in the configuration of claim 4 corresponds to a process in which the cleaning is determined to be required when the determination means determines that cleaning is required. The cleaning is performed.
[0013]
According to a sixth aspect of the present invention, there is provided a semiconductor device manufacturing method including a batch management step and a determination step. In the batch management step, data on foreign matters in each process during the manufacture of the semiconductor wafer is collectively managed. In the determining step, a process to be cleaned is determined based on the data managed in batch. Thus, the same effect as in the first aspect can be obtained.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
First, a manufacturing process of a semiconductor device will be described with reference to FIG. In the semiconductor device manufacturing process, for example, a film forming process (S1) using, for example, a sputtering method or a CVD method, a photoengraving process (P1) for baking a desired pattern, and pattern processing according to the pattern. And an etching step (E1). Each of these processes is actually a source of foreign matter. Therefore, in this embodiment, the number of foreign matters is detected for each process, and these are collectively managed. As a result, a process and an apparatus in which a large amount of foreign matter is generated are clarified. As a result, an accurate cleaning treatment for reducing the foreign matter can be performed, leading to an improvement in operating rate and yield.
[0016]
Thus, in order to collectively manage the number of foreign matters corresponding to each manufacturing process, for example, a configuration as shown in FIG. 2 can be considered. In FIG. 2, a manufacturing apparatus corresponding to each process such as an etching apparatus (E1), a sputtering apparatus (S1), a CVD apparatus (C1), and another etching apparatus (E2), a foreign matter analysis apparatus (I1), and a foreign matter inspection machine. Both the inspection apparatus such as (I2) are connected to the host computer (host computer) 5. Then, the host computer 5 centrally manages the foreign matter data from the etching apparatus (E1) and the like. In that case, the number of foreign matters detected by the etching apparatus (E1) or the like is file-managed for each wafer processing and transmitted to the host computer 5 online. All data of each process is transmitted online to the host computer 5, data accumulation and statistical processing are performed, and trend management (trend management) is performed for each file.
[0017]
In order to achieve the configuration shown in FIG. 2, a configuration different from the conventional configuration is required on the manufacturing apparatus side. FIG. 3 shows a specific structure of the etching apparatus (E1) for achieving the configuration shown in FIG. Referring to FIG. 3, in this etching apparatus, sensors 10 a and 10 b for detecting foreign matter in vacuum chamber 2 are provided in vacuum chamber 2. A CPU 4 that receives a signal from the sensor 10b and exchanges signals with the host computer 5 is also provided in the etching apparatus (E1).
[0018]
A cleaning gas supply device 8 is also provided for supplying a cleaning gas into the vacuum chamber 2 when it is determined that cleaning is necessary. A valve 9 is provided between the cleaning gas supply device 8 and the vacuum chamber 2. Similarly, an etching gas supply device 6 and a valve 7 are also provided. By configuring the etching apparatus (E1) in this way, it is possible to achieve collective management of the foreign matter number data as shown in FIG. Specifically, the number of foreign matters during the etching process is detected by the sensors 10a and 10b, the detection signal is sent to the CPU 4, and data is transmitted from the CPU 4 to the host computer 5 online.
[0019]
The system shown in FIG. 2 can be achieved by configuring the sputtering apparatus (S1) and the CVD apparatus (C1) shown in FIG. 2 in the same manner as the etching apparatus E1 shown in FIG. Further, as shown in FIG. 2, the data of the foreign matter analysis device (I2) (for example, the foreign matter analysis device of KLA, pretester with fail bit map function, etc.) is also transmitted to the host computer 5 to accumulate data and perform statistical processing, etc. To do.
[0020]
Here, the KLA data is data detected by a foreign matter analysis apparatus manufactured by KLA, and specifically, data obtained by detecting the location, number, and content of foreign matter on the foreign matter on the wafer being processed. The fail bit map is used to detect and analyze the position of the chip on the wafer that was defective when measuring the electrical characteristics in the final wafer process, the position of the defective chip, the number of defects, and the content of the defect. Data. The statistical processing methods in the system shown in FIG. 2 are: (1) statistical processing for each process, trend (trend) management, (2) statistical processing by a combination of processes, trend management, (3) Correlation statistical processing between yield data and each process, (4) Correlation statistical processing between foreign matter inspection machines and foreign matter analysis devices, and (5) Foreign matter generation analysis processing based on foreign matter analysis device data.
[0021]
Examples of statistical processing and trend management for each process of (1) above are shown in FIGS. FIG. 4 shows two examples ((a) and (b)) of foreign matter count measurement data of the sputtering apparatus (S1) in the sputtered film formation process of FIG. 1, and FIG. 5 shows the etching apparatus (E1) in the etching process. Two examples ((a), (b)) of the foreign matter count measurement data are shown. FIG. 6 shows the foreign matter count measurement data for each processing wafer of the foreign matter analysis apparatus (I1) in the foreign matter analysis step. Referring to FIG. 4, in the case of (a), it can be seen that the number of foreign matters is always smaller than a preset reference value. However, in the case of (b), it can be seen that the number of foreign substances in a predetermined time exceeds the reference value. Similarly, in FIG. 5, it can be seen that the number of foreign objects does not exceed the reference value in (a), but exceeds the reference value in (b). Further, as shown in FIG. 6, it can be seen that there is a processed wafer that exceeds the reference value even in the foreign matter number data obtained by the foreign matter analyzing apparatus.
[0022]
An example of statistical processing between the processes (2) and a statistical processing by a combination of the processes is shown in FIGS. Specifically, FIG. 7 shows the relationship between the foreign matter number data of the foreign matter analyzer (I1) and the etching device (E1), and FIG. 8 shows the foreign matter number data of the foreign matter analyzer (I1). The relationship with the foreign matter number data of the sputtering apparatus (S1) is shown. Referring to FIG. 7 and FIG. 8, there is a correlation between the number of foreign substances of I1 and the number of foreign substances of E1, but there is not much correlation between the number of foreign substances of I1 and the number of foreign substances of S1. I understand.
[0023]
FIG. 9 and FIG. 10 are shown as examples of the correlation between the above-described yield data (3) and each process. FIG. 9 shows the relationship between the foreign matter number data of the etching apparatus (E1) and the device yield, and FIG. 10 shows the relation between the foreign matter count data of the sputtering apparatus (S1) and the device yield. is there. Referring to FIGS. 9 and 10, it can be seen that the device yield and the number of foreign substances in the etching apparatus (E1) have a correlation, but the device yield and the number of foreign substances in the sputtering apparatus do not have much correlation. .
[0024]
Based on the statistical processing results of FIGS. 7 to 10, the number of foreign substances in the sputtering apparatus and the device yield are not so correlated, so the number of foreign substances is large as in the case of (b) of the sputtering apparatus shown in FIG. 4. Even in this case, it can be seen that cleaning is not always necessary. FIG. 11 shows the case of four cases in which the examples of (a) and (b) shown in FIGS. 4 and 5 are combined. Referring to FIG. 11, when the number of foreign substances in the etching apparatus (E1) is lower than the reference value as in case 3 (a), the number of foreign substances in the sputtering apparatus (S1) exceeds the reference value. However, (b) cleaning is not necessarily performed. Conventionally, in this case 3, the sputtering apparatus is cleaned, but in this embodiment, the cleaning can be omitted, and the yield is improved without reducing the operating rate of the apparatus. Can do.
[0025]
Further, the correlation statistical processing between the foreign matter analysis devices in the above (4) is not shown, but for example, foreign matter data (number of foreign matters in each process) in the KLA device and fail bit data (chip) in the pretester. The probability of becoming NG as an electrical characteristic). As a result, a process that is truly involved in the yield is found, and the foreign matter is reduced and management is strengthened from the correlation data. In addition, in the foreign matter generation analysis process based on the foreign matter analysis device data of (5) above, KLA data (place of foreign matter in each process) and fail bitmap data (place where the chip becomes NG as electrical characteristics) are superimposed. Analyze the source of foreign matter. A specific example will be described with reference to FIGS. FIG. 12 shows fail bit map data (where the chip becomes NG as an electrical characteristic) with a cross. FIG. 13 shows the result of analyzing the location of foreign matter in each process using a foreign matter analyzer (I1) manufactured by KLA. A circle indicates the location of a foreign object. A circle mark is attached to the place of the x mark in FIG. 12 corresponding to the place where the mark x shown in FIG. 12 and the circle mark shown in FIG. 13 match. It can be seen that at the position having both the x and the ◯ marks shown in FIG. 12, a chip defect has occurred due to foreign matter.
[0026]
By the statistical processing of (1) to (5) described above, it is possible to analyze which foreign substance in the process affects the product yield, and to manage the processes that affect the device characteristics with priority. There is an advantage that you can.
[0027]
Note that the correlations described above change due to changes in the device configuration, changes in the device itself, changes in the process, and changes in the production type. Therefore, it is necessary to determine a treatment method (cleaning method) based on the result of statistical processing by the host computer 5.
[0028]
In this embodiment, as described above, the host computer 5 is used to collectively manage the number of foreign matters in each process, and by analyzing the correlation between the data and the final product yield, It is possible to easily determine which process of the manufacturing apparatus should be cleaned at the timing. Further, for the device to be cleaned, which is found by the host computer 5, a signal is sent to each process device to give an instruction for cleaning. As a result, signals are processed in the CPU of each apparatus. For example, in the etching apparatus shown in FIG. 3, the etching process is interrupted and the sequence is changed to a self-cleaning sequence. Thereby, the supply of the etching gas from the etching gas supply device 6 is automatically stopped by the valve 7, and then the cleaning gas is automatically supplied from the cleaning gas supply device 8 into the vacuum chamber 2 by the operation of the valve 9. Cleaning is performed. Similar operations are performed for other devices.
[0029]
A schematic flow of the cleaning operation by the host computer described above is shown in FIG. Referring to FIG. 14, this process is all performed online. In addition, the foreign matter analysis apparatus can also analyze the type of foreign matter (whether it is dust or metal), and the pretester with a fail bit can analyze which process is defective.
[0030]
In the above embodiment, the combination of the etching apparatus and the sputtering apparatus has been described. However, the present invention is not limited to this, and the present invention can be similarly applied to a combination of apparatuses between other processes. In addition, the case where the right or wrong of the cleaning is determined based on the combination of the foreign matter analysis data and the foreign matter number data of each process has been described. However, the determination may be made based only on the foreign matter number data of each step. If statistical processing is possible, the same effect is produced. Further, it may be determined which process should be cleaned based on a combination of foreign matter analysis data only. Furthermore, in the present embodiment, the method of detecting foreign matter data inside the apparatus and transmitting it to the host computer online has been described. However, the present invention is not limited to this, and the foreign matter monitor wafer itself is used using the foreign matter monitor wafer. It is also possible to detect the number of foreign matter data. Further, even in a semiconductor manufacturing system including six or more devices shown in FIG. 2, a foreign substance number detecting means may be provided for each device and brought online.
[0031]
【The invention's effect】
As described above, according to the semiconductor device manufacturing system of any one of claims 1 to 5, by appropriately cleaning the manufacturing apparatus in each step, the yield (non-defective product ratio) can be achieved without reducing the operating rate of the apparatus. ) Can be improved.
[0032]
According to the semiconductor device manufacturing method of the sixth aspect, since unnecessary cleaning can be omitted, the yield can be improved without reducing the operation rate of the device.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a manufacturing process of a semiconductor device according to an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a configuration of a semiconductor device manufacturing system according to an embodiment of the present invention;
FIG. 3 is a configuration diagram showing details of a host computer and an etching apparatus shown in FIG. 2;
4 is a correlation diagram showing the relationship between the time and the number of foreign matter data in the sputtered film forming step shown in FIG.
5 is a correlation diagram showing the relationship between the time in the etching process shown in FIG. 1 and the number of foreign matter data.
6 is a diagram showing the number of foreign matter data for each processing wafer in the foreign matter analyzing apparatus in the foreign matter analyzing step shown in FIG. 1. FIG.
FIG. 7 is a correlation diagram showing the relationship between the number of foreign matters in the foreign matter analyzing apparatus (I1) and the number of foreign matters in the etching apparatus (E1).
8 is a correlation diagram showing the relationship between the number of foreign substances in the foreign substance analyzing apparatus (I1) and the sputtering apparatus (S1) in the foreign substance analyzing step shown in FIG.
FIG. 9 is a correlation diagram showing the relationship between the device yield and the number of foreign substances in the etching apparatus (E1).
FIG. 10 is a correlation diagram showing the relationship between the device yield and the number of foreign substances in the sputtering apparatus (S1).
FIG. 11 is a diagram showing a combination treatment method in the case of (a) and (b) shown in FIG. 4 and FIG. 5;
FIG. 12 is a plan view showing the position of a defective chip on a semiconductor wafer.
FIG. 13 is a diagram showing the position of foreign matter on a semiconductor wafer by the foreign matter analysis apparatus.
FIG. 14 is a diagram showing a schematic flow of a cleaning operation by the host computer of the present invention.
FIG. 15 is a schematic diagram for explaining a configuration of a conventional etching apparatus and a foreign matter inspection / processing step.
[Explanation of symbols]
2 vacuum chamber, 4 CPU, 5 host computer, 8 cleaning gas supply device, 9 valve, 10a, 10b sensor.

Claims (6)

A collective management means for centrally managing data on foreign matters in each process during the manufacturing process of a semiconductor wafer;
Based on the data from the centralized management unit, and data relating to the foreign matter in the respective steps, the contrast and the yield data of the final product of the semiconductor wafer to be manufactured through the respective steps, and generation of foreign substances in each process A semiconductor device manufacturing system, comprising: a discriminating means for analyzing a correlation with a yield rate of a semiconductor wafer to be manufactured and discriminating a process to be cleaned based on the result .   2. The semiconductor device manufacturing system according to claim 1, further comprising a manufacturing apparatus and an inspection apparatus corresponding to each of the steps, wherein data relating to the foreign matter is transmitted online from the manufacturing apparatus and the inspection apparatus to the collective management unit.   2. The semiconductor device manufacturing system according to claim 1, further comprising a manufacturing apparatus corresponding to each of the steps, wherein the manufacturing apparatus includes means for detecting a foreign substance in the manufacturing apparatus.   2. The semiconductor device manufacturing system according to claim 1, further comprising a manufacturing apparatus corresponding to each of the steps, wherein the manufacturing apparatus includes a cleaning unit for cleaning the inside of the manufacturing apparatus.   5. The semiconductor device manufacturing system according to claim 4, wherein the cleaning unit performs cleaning of a manufacturing apparatus corresponding to a process in which the cleaning is determined to be necessary when the determination unit determines that cleaning is necessary. 6. A step of collectively managing data on foreign matters in each process during the manufacturing process of a semiconductor wafer, a data on foreign matters in each step based on the data being collectively managed, and a semiconductor wafer manufactured through each step Compared with the final product yield data , analyze the correlation between the generation of foreign matter in each process and the yield rate of the manufactured semiconductor wafer, and determine the process to be cleaned based on the result A method for manufacturing a semiconductor device.

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