KR100272250B1 - System and method for carrying wafer in semiconductor manufacturing equipment - Google Patents

Abstract

PURPOSE: A system for transferring a wafer of equipment for manufacturing a semiconductor is provided to inspect an intrinsic characteristic of each equipment during an unit process and variance of a process characteristic caused by continuity of a process of each step, by automatically and sequentially disposing the wafers by a run unit. CONSTITUTION: A unit(102) for fixing a cassette is mounted in a predetermined portion on a system body(100). A plurality of wafers(114) are loaded in the first cassette(104) mounted on the unit for fixing the cassette. An apparatus(106) for searching for a proper number is mounted on the system body at one side of the first cassette, vertically moving in straight light motion. A cassette transfer unit(108) is mounted on the system body separated from the apparatus for searching for the proper number by a predetermined interval, vertically moving in straight light motion. The wafers are unloaded from the second cassette(110) mounted on the cassette transfer unit. A wafer transfer robot(112) is mounted on the system body at the other side of the first cassette, vertically moving in straight light motion.

Description

Wafer transfer system of semiconductor manufacturing equipment and wafer transfer method using same {System and method for carrying wafer in semiconductor manufacturing equipment}

The present invention relates to a wafer transfer system of a semiconductor manufacturing facility and a wafer transfer method using the same, and more particularly, after recognizing a unique number marked on the wafer itself using a unique number retrieval device, The present invention relates to a wafer transfer system of a semiconductor manufacturing facility and a wafer transfer method using the same, which automatically arranges wafers sequentially (ascending / descending / hole, even / individual selection).

The semiconductor manufacturing equipment has made remarkable progress until now in the GIGA era. It is already recognized that these semiconductor manufacturing facilities, which are as complex as the manufacturing process and are equipped with various automated functions and improved control technology, play a central role in determining the characteristics and manufacturing technology of semiconductor products.

Therefore, in order to carry out hundreds of process steps required in the manufacture of semiconductor devices in accordance with the set process conditions, stability of the equipment mechanism in which the actual process is performed is required.

As such, the stability of the equipment mechanism is complicated by the semiconductor device manufacturing process. In view of the various series of processes, the unique parameters and processes of the unit process are different for each step, and the wafer processing order is also random. This is because there are hundreds of factors that can change the set process conditions during hundreds of processes and the complete product.

In particular, each unit process corresponding to the hundreds of processes required to produce one finished product is not a single process, but each process is related to each other by integrating the processes before and after the process. Since the process proceeds continuously through a process test step to verify that the processes are performed properly, the result is verified. Therefore, when manufacturing a device having a high level of integration, the stability of the installation mechanism is required more. It must be. This will be described with reference to the dry etching process which is widely used in manufacturing a semiconductor device as an example. Here, for convenience, two control points corresponding to the input and output factors are set in the process of repeating a single process, and based on this, the semiconductor manufacturing equipment mechanism will be described to influence the semiconductor device manufacturing. I want to see. This method is called statistical process control. At this time, the distinction between the input factor and the output factor is specified in Table 1.

Table 1.

Input argument equipment Gas, temperature, pressure Strong semiconductor manufacturing equipment Environment Temperature, clean humidity etc. Strong semiconductor manufacturing equipment Way Process sequence, stagnation time in the etch chamber, etc. Strong semiconductor manufacturing equipment Output argument inspection Critical demention, etch rate, process dispersion, defects, profile status, etc. Process verification

In Table 1 above, the input factors represent aspects of the semiconductor manufacturing equipment (eg, dry etching apparatus) in which dry etching is performed, while the output factors are products made after the dry etching process (eg, the film quality patterned on the wafer). Indicates the properties.

Referring to Table 1, it can be seen that the fine line width or etching rate of the patterned film quality, which is a characteristic of the output factor, is determined by the process conditions of the input factor. From this, when the stability of the manufacturing equipment mechanism is not secured, it can be confirmed that the failure of the output factor during the actual process is inevitably generated.

In FIG. 1, in order to more clearly confirm this, a graph showing a change in growth rate of a thin film over time when a thin film is formed on a plurality of wafers in a batch method is presented. In the figure, the horizontal axis represents time and the vertical axis represents the growth rate of the thin film on the wafer. N1 ----- Nx represents a wafer number.

Referring to the graph, when the thin film is grown on the initial N ₁ wafer, the thin film is grown at the growth rate of V1, but gradually, RF is required to grow the thin film on the wafer corresponding to Nx over time. (raido frequency) Due to the heating, the temperature inside the reactor gradually increases, and in the last case, it can be observed that the thin film grows in the V2 state in which the growth rate in the reactor is changed by ΔV compared to the initial V1 speed. . When the growth rate is changed as described above, a difference occurs gradually in the thickness of the film grown on the wafer, resulting in a process defect.

If such a process defect occurs, if the thickness value of the deposited thin film is not included in the standard value (set value ± 0.5%) in the process inspection work performed after completion of the unit process, it is treated as a defective product and disposed of. When included in the reference value, the following unit process is continuously performed.

Therefore, in the case of a wafer in which the thickness of the thin film grown on the wafer is different from the set value but included in the reference value range and the subsequent process is performed as it is, even if the process defect is judged by the process inspection work performed after the unit process for each step thereafter, In practically no facility, it is not possible to know specifically how many such failures have occurred during the process.

This is because the current wafer processing method is not based on a certain rule, but follows a random method for each process. Here, the random method means that the wafer is variably loaded into the cassette according to the order in which the process is completed regardless of a predetermined rule (for example, a unique number marked on the wafer) after completion of the unit process.

Typically, each unit goes through several hundred processes until a single product is made, and each unit is processed in a batch and single manner. It can be estimated how random the wafer processing method can be during the process. Here, a typical process for applying a batch method may include a process using a diffusion furnace, and a typical process for applying a single method may include a dry etching process or an ion implantation process. In addition, a typical process of the semi-batch method is a vapor phase chemical vapor deposition (CVD) process. Here, the semi-batch method means that when the wafer is introduced into the manufacturing facility, the wafer is introduced in a batch method, but the actual process is performed individually by one wafer.

As such, when the wafer is loaded into the cassette in a random state, it is impossible to verify the correlation between the defect factors generated in each unit process and the input factors of the semiconductor manufacturing equipment using only the wafer having a defective process. .

Therefore, in order to properly grasp the relationship between the input factor with a strong mechanical aspect and the output factor with a strong character of the product, a lot of research and development must be preceded to solve the problems mentioned above.

In the present invention, by using a technology that automatically arranges the wafers sequentially, it is possible to combine the history of the semiconductor manufacturing equipment itself with the time when the process failure occurs, thereby clearly verifying the status of each equipment during the unit process in progress. I want to be able to.

The object of the present invention is to automatically arrange the wafers sequentially (in ascending order / descending order / hole, even number / individual selection) at every unit process progress using the semiconductor manufacturing equipment. The present invention provides a wafer transfer system of a semiconductor manufacturing facility and a wafer transfer method using the same so that process characteristics change according to intrinsic characteristics and continuity of a step-by-step process can be clearly verified.

1 is a prior art, a graph showing a change in growth rate of a thin film over time when forming a thin film on a plurality of wafers in a batch method,

2 is a cross-sectional view showing the structure of a wafer transfer system of a semiconductor manufacturing facility according to a first embodiment of the present invention;

3 is a perspective view illustrating a state in which 25 wafers are loaded in a unit of run into a first cassette constituting the wafer transfer system of FIG. 1;

FIG. 4 is an enlarged main view of the flat zone of the individual wafers shown in FIG. 3;

FIG. 5 is a schematic diagram illustrating a method of searching for a wafer unique number using a unique number searching device of the wafer transfer system of FIG. 1; FIG.

FIG. 6 is a view showing a unique number search result of individual wafers on a computer screen using a unique number searching device of the wafer transfer system of FIG. 1;

7 is a cross-sectional view showing the structure of a wafer transfer system of a semiconductor manufacturing facility according to a second embodiment of the present invention;

8 is a cross-sectional view showing the structure of a wafer transfer system of a semiconductor manufacturing facility according to a third embodiment of the present invention;

9 is a table showing an example of wafer alignment according to the selection of the wafer processing method (ascending / descending / hole, even / individual selection).

In order to achieve the above object, the present invention provides a system body, a cassette holder mounted on a predetermined portion on the system body, a first cassette mounted on the cassette holder, and loaded with a plurality of wafers, and the first cassette. It is mounted on one side of the system body, and the unique number search device designed to enable a linear movement up and down, mounted on the system body at a point spaced apart from the unique number search device, a linear movement up / down A cassette carrier table capable of being mounted, a second cassette mounted on the cassette carrier table, and a wafer unloaded, and mounted on the system body on the other side of the first cassette, and capable of linear movement up and down A wafer transfer system of a semiconductor manufacturing facility consisting of a robot is provided.

At this time, the unique number retrieval apparatus is composed of a support, a letter recognition unit attached to a predetermined portion of one side of the support, the wafer transfer robot is a wafer transfer arm on which the wafer is mounted and a support vertically attached to the wafer transfer arm It consists of. Here, the height of the unique number retrieval device is preferably 40 ~ 50cm, the length of the wafer transfer arm is preferably 33 ~ 37cm. The letter recognition unit is fixed to be inclined at an angle of 45 ° with respect to the horizontal plane on which the wafer is placed, and the wafer transfer arm is designed to allow left / right linear movement.

According to the invention, the wafer transfer system may be designed such that a wafer transfer robot is mounted on the system body between the second cassette and the serial number retrieval device, while the center portion between the first and second cassettes is in the vertical direction. The wafer transfer system may be designed such that a third cassette holder on which the third cassette is mounted is further mounted on the linearly extending system body. In this case, the third cassette is an unloading cassette in which no wafer is loaded, and in the case where the wafer transfer system is designed such that the first to third cassettes are provided on the system body, the cassettes are spaced apart from each other by a central portion. Mount each cassette to be placed in the

At this time, the wafer transfer arm of the wafer transfer robot is preferably manufactured to have a length of 22 ~ 24cm, the wafer transfer robot is designed to be rotatable within a 180 ° range.

As such, the sequential alignment of the wafers allows the engineer to artificially determine the number of wafers (e.g., 22 to 24 wafers) that do not require the individual wafers to be inspected during the process inspection. The process inspection work may be performed in such a manner as to inspect only), thereby reducing the time loss required during the process inspection work. Each time the unit process is repeated, wafers can be automatically sorted sequentially (ascending / descending / hole, even / individual selection) based on the specified wafer processing method, and the process according to the continuity of the process by step It is possible to clearly verify the characteristic change.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

2 is a cross-sectional view showing the structure of the wafer transfer system of the semiconductor manufacturing facility according to the first embodiment of the present invention, which enables the wafers to be automatically aligned in sequence. Looking at the structure of the wafer transfer system in detail with reference to the cross-sectional view as follows.

In the wafer transfer system of the semiconductor manufacturing facility shown in FIG. 2, a cassette holder 102 is mounted on a predetermined portion of the system body 100, and a plurality of wafers (eg, 25 sheets) are loaded on the cassette holder 102. The first cassette 104 is mounted, and the unique number retrieval device 106 is designed on the body of the system 100 on one side of the first cassette 104 to allow the up / down linear movement by a gear method. A cassette moving table 108 is mounted on the system body 100 at a point spaced apart from the unique number retrieval device 106 by a gearing method. On the movable table 108, a second cassette 110 having an unloaded wafer is mounted, and on the other side of the system cassette 100 on the other side of the first cassette 104, up / down linear movement is possible by a gear method. Designed wafer It has a structure in which the transfer robot 112 is mounted. In this case, the wafer transfer system is configured to be connected to the computer 115 in a network manner.

FIG. 3 is a perspective view illustrating a state in which 25 wafers 114 are loaded in slits (slits 1 to 25 slits) in the first cassette 104 in a run unit. The flat zone portion (a) of the wafer 114 is marked with a unique number (eg, an individual number (# 02) and a lot name (7UD875)) of the wafer, as can be seen in the detail diagram shown in FIG. It is marked.

The unique number retrieval device 106 is designed to have a height of 40 ~ 50cm, the support 106b is largely mounted on the system body 100, and the letters attached to a predetermined portion of one side of the support 106b It consists of the recognition part 106a. At this time, the character recognition unit 106a is fixed to the support 106b to be inclined at an angle of 45 ° with respect to the horizontal plane on which the wafer 114 is placed, as shown in the schematic diagram shown in FIG. 5. As such, the character recognition unit 106a is fixed to the unique number retrieval unit 106 by marking the unique numbers marked on each of the 25 wafers loaded in the slits in the first cassette 104 at a constant pitch. ) So that you can search smoothly.

The wafer transfer robot 112 is composed of a support 112a mounted on the system body 100 and a wafer transfer arm 112b mounted on an upper surface of the support 112a, and the wafer transfer arm 112b. ) Is designed to allow left / right linear movement. Here, the wafer transfer arm 112b is designed to have a length of 33 to 37cm, and the support 112a is designed to have a height of 28 to 30cm.

In this case, the first cassette 104 and the second cassette 110 constituting the wafer transfer system are mounted such that the cassettes 104 and 110 are disposed at positions corresponding to each other on the system body 100. . This is because when the wafer located in any slot in the first cassette 104 is transferred to the slot corresponding to the correct position in the second cassette 110, the wafer in the first cassette 104 is transferred to the wafer transfer device. This is because the wafer is transferred in such a manner as to be pushed into the second cassette 110 to a horizontal position on the plane by using the 112.

Therefore, in the case of the first embodiment, the wafer transfer operation is performed through the following three steps.

As a first step, first, the number of wafers loaded in a run unit is checked. More specifically, as shown in FIG. 3, it is checked whether all 25 wafers 114 are filled in the first cassette 104 in which the wafers 114 are loaded in a run unit, and whether or not they exist. If all 25 wafers are not filled and an empty slot is found, the wafer transfer robot 112 aligns the wafers by automatically filling the empty slot with the wafer loaded in the next slot. .

Subsequently, the unique numbers of the 25 wafers 114 loaded in the first cassette 104 are sequentially searched through the letter recognition unit 106a of the unique number retrieval device 106, and networked to the wafer transfer system. Display the result on the computer screen 116 connected in a manner. 6 shows a computer screen 116 displaying search results. Here, the lot names marked on the wafer 114 are displayed identically to 7UD007 because all 25 wafers represent wafers loaded in the first cassette 104.

At this time, the search operation using the character recognition unit 106a moves each unique number retrieval device 106 in a vertical downward direction sequentially from the slot number 25 of the first cassette 114, and each wafer 114 The unique number (individual number and lot name) marked on the flat zone part of) is read by scanning an image of a numerical image indicated within a specific width of a specific position such as a facsimile head.

As such, performing the number of wafer checks prior to the wafer identification number retrieval operation may reduce the time required to transfer the wafers when the transfer operation is performed after the number of wafers has been checked. Because. Here, the wafer number checking operation can be skipped.

As a second step, the wafer processing method is specified based on the arrangement selection criteria (1 ascending order, 2 descending order, 3 individual selection) set within the computer 115.

As a third step, referring to the search result displayed on the computer screen 116, the search device 216 is moved into the system body 100 by moving the unique number search device 106 vertically. In the state where it is sent down by a predetermined depth, the 25 cassettes loaded in the first cassette 104 are sequentially transferred to the second cassette (using the wafer transfer robot 112) by the wafer processing method specified in the second step. 110) Load it in place. In-situ position in the second cassette 110 means that individual wafers are arranged in the second cassette 110 when the 25 wafers 114 are automatically arranged toward the second cassette 110 by a designated wafer processing method. Indicates a suitable location to be loaded.

The third step will be described in more detail as follows. As an example, the case where 25 wafers 114 are aligned in ascending order will be described.

First, the wafer 114 loaded in slot 25 of the first cassette 104 is mounted on the wafer transfer arm 112b of the wafer transfer robot 112. Next, in order to load the wafer 114 in the second position of the cassette 110 (for example, the position of slot 5), the cassette carrier 108 is upwardly moved by a predetermined height. Make a linear movement. In this state, the wafer transfer arm 112b on which the wafer 114 is mounted is pushed to the slot number 5 in the second cassette 110 in a horizontal position on a plane. As a result, the fifth wafer 114 is transferred to the correct position of the second cassette 110 (for example, the position of the fifth slot).

If the same operation is repeatedly performed on the remaining 24 wafers 114 loaded in the first cassette 104, the operation in the first cassette 104 is performed in accordance with the designated wafer processing method (for example, ascending order). All 25 wafers 114 can be loaded in place in the second cassette 110.

In the same manner as described above, when the wafer transfer operation is performed at every unit process, it is possible to clearly verify the process characteristic change according to the continuity of the step-by-step process. In addition, this makes it possible to analyze the process characteristics for each unit process, thereby making it possible to easily analyze the state of the semiconductor manufacturing equipment.

Meanwhile, as shown in the cross-sectional view of FIG. 7, the wafer transfer system mounts the system on the system body between the first cassette and the second cassette, not on one side of the first cassette. You can also design it.

Here, FIG. 7 is a cross-sectional view showing the structure of the wafer transfer system of the semiconductor manufacturing equipment according to the second embodiment of the present invention, which allows the wafers to be automatically aligned in sequence.

Referring to the cross-sectional view, the wafer transfer system is equipped with first and second cassette holders 202 and 208 to be spaced apart from each other by a predetermined portion on the system body 200, the first cassette holder ( A first cassette 204 loaded with a plurality of wafers 214 is mounted on 202, and a second cassette 210 unloaded with a wafer is mounted on the second cassette holder 208. On the system body 200 between the 204 and the second cassette 208 is mounted a wafer transfer robot 212 is designed to enable the up / down linear and rotational movement by the gear system, the wafer transfer robot ( On the system body 200 between the 212) and the first cassette 204, it can be seen that the unique number retrieval device 206 designed to enable the up / down linear movement by the gear system is mounted. . In this case, the wafer transfer system is configured to be connected to the computer 115 in a network manner.

The wafer transfer robot 212 is the same as the wafer transfer robot 112 of the first embodiment in that it is composed of a support (212a) and the wafer transfer arm (212b), so that 180 ° rotational movement is possible in addition to the up / down linear movement The difference is that it is designed. In this case, the wafer transfer arm 212b is designed to enable left / right linear movement, and its length is manufactured to have a length of 22 to 24 cm. And, the support 212a is manufactured to have a height of 28 ~ 30cm.

Here, the length of the wafer transfer arm 212b is shorter than that of the first embodiment, so that the wafer transfer robot 212 may be moved to the first and second cassettes in order to enable the wafer 214 to be transported at the shortest distance. It is because it arrange | positioned to the center part of (204) and (210).

The unique number retrieval apparatus 206 is composed of the support 206b and the character recognition unit 206a as in the first embodiment, the total height is made of 40 ~ 50cm. At this time, the letter recognition unit 206a is fixed to the support 106b to be inclined at an angle of 45 ° with respect to the horizontal plane on which the wafer is placed, as mentioned above.

In this case, the first cassette 204 and the second cassette 210 constituting the wafer transfer system are mounted such that the cassettes 204 and 210 are disposed at positions corresponding to each other on the system body 200. .

On the other hand, as a variation of the second embodiment, the wafer transfer system 212 is capable of only a linear movement of the wafer transfer robot 212 by the gear method, while the wafer transfer arm 212b constituting the wafer transfer system is It can also be designed to allow both left and right linear and rotary motions. As such, when designing a wafer transfer system, the wafer transfer arm 212b is designed to be rotatable by 180 °.

Therefore, in the case of the second embodiment, the wafer transfer operation is performed through the following three steps.

As a first step, first, the number of wafers loaded in a run unit is checked in the same manner as in the first embodiment. As a result of checking the wafer loading quantity, if all 25 wafers are not filled and an empty slot is found, the wafer transfer robot 212 is used to automatically fill the empty slot with the wafer loaded in the next slot. To align the wafer.

Subsequently, the unique numbers of the 25 wafers 214 loaded in the first cassette 204 are sequentially searched through the letter recognition unit 206a of the unique number retrieval device 206, and networked to the wafer transfer system. Display the result on the computer screen 116 connected in a manner. 6 shows a computer screen 116 displaying search results.

In this case, the search operation using the character recognition unit 206a moves each unique number retrieval device 206 sequentially from the slot number 25 of the first cassette 214 in a vertical downward direction, and thus each wafer 214. The unique number marked on the flat zone part of) is scanned by scanning an image of a numerical image marked within a specific width of a specific position, such as a facsimile head. In this case, too, the wafer number confirmation operation can be skipped.

As a second step, the wafer processing method is specified based on the arrangement selection criteria (1 ascending order, 2 descending order, 3 individual selection) set within the computer 115.

As a third step, referring to the search result displayed on the computer screen 116, the search device 206 is moved into the system body 200 by moving the unique number search device 206 vertically downward. In the state where the wafer is lowered by a predetermined depth, the 25 cassettes loaded in the first cassette 204 are sequentially stacked by using the wafer transfer robot 212 by the wafer processing method specified in the second step. To the correct position in the 210).

The third step will be described in more detail as follows. As an example, the case where 25 wafers 214 are arranged in ascending order will be described.

First, the fifth wafer 214 loaded in the slot 25 of the first cassette 204 is mounted on the wafer transfer arm 212b of the wafer transfer robot 212. Next, the wafer transfer robot 212 on which wafer 5 is mounted 214 is moved to the correct position of the second cassette 210 (for example, the position of slot 5) based on the designated wafer processing method. Thereafter, the wafer transfer robot 212 is rotated at an angle of 180 °. In this state, the wafer transfer arm 212b on which wafer 5 is mounted is pushed to the slot 5 position in the second cassette 210 in a horizontal position on a plane. As a result, wafer 5 (214) is transferred to the correct position of the second cassette (210, for example, slot 5).

If the same operation is repeatedly performed on the remaining 24 wafers 214 loaded in the first cassette 204, the operation in the first cassette 204 is performed in accordance with the designated wafer processing method (for example, ascending order). All 25 wafers 214 can be loaded in place in the second cassette 210.

On the other hand, as in the modification of the second embodiment, the wafer transfer robot 212 is capable of only up / down linear movement, and when the wafer transfer system is designed such that the wafer transfer arm 212b constituting it is capable of rotational movement, The wafer is transferred into the second cassette 210 according to the following method. In this case, since the first and second steps proceed in the same manner as in the second embodiment, the description is avoided, and the description will be mainly focused on the third step after the wafer identification number search operation and the wafer processing method designation are completed. In this case, the case where the 25 wafers 214 are arranged in ascending order will be described.

First, slot 25 in the first cassette 204 in a state in which the serial number retrieval device 206 is moved vertically downward and the retrieval device 206 is lowered into the system body 200 by a predetermined depth. Wafer 214 loaded on the wafer is mounted on the wafer transfer arm 212b of the wafer transfer robot 212, and the wafer transfer robot on which wafer 5 is mounted 214 based on a specified wafer processing method (for example, ascending). 212 is moved to the correct position (eg, the position of slot 5) of the second cassette 210.

Subsequently, the wafer transfer robot 210 is left unrotated and rotates only the wafer transfer arm constituting the wafer at an angle of 180 °. In this state, the wafer transfer arm 212b on which wafer 5 is mounted is pushed to the slot 5 position in the second cassette 210 in a horizontal position on a plane. As a result, wafer 5 (214) is transferred to the correct position of the second cassette (210, for example, slot 5).

By repeating the above operation on the remaining 24 wafers 214 loaded in the first cassette 204, the wafer transfer operation is completed.

In addition, as shown in the plan view shown in FIG. 8, the wafer transfer system mounts the wafer transfer robot on the system body between the first cassette and the second cassette rather than on one side of the first cassette, The wafer transfer system may be designed in such a manner that a third cassette is further mounted on the system body at a predetermined distance from the first and second cassettes.

Here, FIG. 8 shows a plan view showing the structure of the wafer transfer system of the semiconductor manufacturing equipment according to the third embodiment of the present invention, which allows the wafers to be automatically aligned sequentially. In the above embodiment, the plan view instead of the cross-sectional view is intended to increase the understanding of the structure of the system.

Referring to the plan view, the wafer transfer system includes first to third cassette holders 302, 308, and 314 mounted to be spaced apart from each other at predetermined portions on the system body 300. The first cassette 304 loaded with the plurality of wafers 314 (eg, 25 sheets) is mounted on the first cassette holder 302, and the wafers are mounted on the second and third cassette holders 308 and 314. Unloaded second and third cassettes 310 and 316 are mounted, and on the system body 300 between the first cassette 304 and the second cassette 310 up / down by a gear method. A wafer transfer robot 312 designed to allow linear and rotational movements is mounted. The wafer transfer robot 312 is mounted on the system body 300 between the wafer transfer robot 312 and the first cassette 304 by a gearing method. Structure equipped with unique number search device 306 designed to enable linear movement It can be seen that consisted of. In this case, the wafer transfer system is configured to be connected to the computer 115 in a network manner.

Here, the first and second cassettes 304 and 310 are disposed at positions corresponding to each other on the system body 300, and the third cassette 316 is the first and second cassettes 304. , 310 is mounted to be disposed on a line extending in the vertical direction. In this case, it is noted that the first to third cassettes 304, 310, and 316 are arranged to be equally spaced from each other from the center of the first and second cassettes 304 and 310.

As described above, disposing the first to third cassettes 304, 310, and 316 so as to be equally spaced apart from the center portion is such that the wafer transfer robot 312 of the wafer transfer system is within a certain range. This is because the up / down linear motion and the rotational motion are designed so that it is difficult to accurately transfer the wafer when the cassette is disposed at a position beyond this range.

As described above, when two unloaded cassettes are mounted on the system body 300, an engineer selectively sorts individual wafers or sorts individual wafers by an odd number or an even number. The advantage is that the wafers can be easily aligned when they are to be aligned.

The wafer transfer robot 312 is the same as the wafer transfer robot 112 of the first and second embodiments in that the wafer transfer robot 312 is composed of the support 312a and the wafer transfer arm 312b. There is a difference in that it is designed to enable rotational movement. In this case, the wafer transfer arm 312b is designed to allow left / right linear movement, and its length is manufactured to have a length of 22 to 24 cm. And, the support 312a is manufactured to have a height of 28 ~ 30cm.

Here, the shorter length of the wafer transfer arm 312b than that in the first embodiment may allow the wafer transfer robot 312 to carry the first to third cassettes in order to transport the wafer 314 within the shortest distance. It is because it arrange | positioned to the center part of 304,310, and 316.

The unique number retrieval apparatus 306 is large, as shown in the schematic diagram of Figure 5, consisting of a support and the character recognition portion, the total height is made of 40 ~ 50cm. As described above, the letter recognition unit is fixed to the support to be inclined at an angle of 45 ° with respect to the horizontal plane on which the wafer is placed.

On the other hand, as a modification of the third embodiment, the wafer transfer system 312 is capable of only a vertical movement of the wafer transfer robot 312 by a gear method, while the wafer transfer arm 312b constituting the wafer transfer system is provided. It can also be designed to allow both left and right linear and rotary motions. As such, when designing a wafer transfer system, the wafer transfer arm 312b is designed to be rotatable 90 ° or 180 °. Here, when the wafer transfer arm 312b is rotated by 90 °, the wafer transfer arm 312b is disposed toward the third cassette 316. On the other hand, when the wafer transfer arm 312b is rotated by 180 °, the wafer transfer arm 312b is rotated by 180 °. 2 will be disposed toward the cassette (310).

Therefore, in the case of the third embodiment, the wafer transfer operation is performed through the following three steps. Here, since the wafer transfer operation is performed in the same manner as the first and second embodiments, the first and second steps will be described only briefly, and the following description will focus on the third step.

As a first step, first, the number of wafers loaded in a run unit is checked. As a result of checking the number of wafers loaded, if all 25 wafers are not filled and an empty slot is found, the wafer transfer robot 312 is used to automatically fill the empty slot with the wafer loaded in the next slot. To align the wafer.

Thereafter, the unique numbers of the 25 wafers loaded in the first cassette 304 are searched through the character recognition unit of the unique number retrieving device 306 by scanning, and the results are displayed on the computer screen 116. In this case, the wafer loading number checking operation may be skipped.

As a second step, a wafer processing method is specified based on the array selection criteria (1 hole, even order, 2 individual selection) set in the computer 115 by itself.

As a third step, referring to the search result displayed on the computer screen 116, the search device 306 is moved into the system body 300 by moving the unique number search device 306 vertically downward. In the state of descending by a predetermined depth, the 25 cassettes loaded in the first cassette 304 are sequentially transferred to the second cassette (using the wafer transfer robot 312 by the wafer processing method specified in the second step). 310 to the correct position in the load.

The third step will be described in more detail as follows. As an example, a case in which 25 wafers 314 are aligned by dividing the unique numbers of the wafers in odd and even order will be described.

First, the wafer 314 loaded in the slot 25 of the first cassette 304 is mounted on the wafer transfer arm 312b of the wafer transfer robot 312. Next, based on the designated wafer processing method, the wafer transfer robot 312 on which the wafer 5 is mounted 314 is moved to the correct position of the second cassette 310 (for example, the position of the slot 3). . Thereafter, the wafer transfer robot 312 is rotated at an angle of 180 °. In this state, the wafer transfer arm 312b on which wafer 5 is mounted is pushed to the slot 3 position in the second cassette 310 in a horizontal position on a plane. As a result, wafer 5 (314) is transferred to the correct position of the second cassette (310, for example, slot 3).

If the wafer loaded in slot 25 of the first cassette 304 is not wafer 5 but wafer 6, the wafer transfer robot is rotated by 90 ° only to rotate the wafer 314 in the third cassette ( The wafer may be transferred in such a manner as to be loaded on the 316.

If this operation is repeatedly performed on the remaining 24 wafers 314 loaded in the first cassette 304 in the same manner, the 25 wafers in the first cassette 304 ( All of the 314 can be loaded in place in the second cassette 310.

On the other hand, as in the modification of the third embodiment, the wafer transfer robot 312 is capable of only up / down linear movement, and the wafer transfer system is designed such that the wafer transfer arm 312b constituting the wafer transfer arm can be rotated. The wafer 314 is transferred into the second and third cassettes 310 and 316 according to the following method. In this case, since the first and second steps proceed in the same manner as in the second embodiment, the description is avoided, and the description will be mainly focused on the third step after the wafer identification number search operation and the wafer processing method designation are completed. In this case, a case in which 25 wafers 314 are aligned by dividing the unique numbers of the wafers 314 into odd and even numbers will be described.

First, slot 25 in the first cassette 304 in a state in which the serial number retrieval device 306 is moved vertically downward and the retrieval device 306 is lowered into the system body 300 by a predetermined depth. The wafer transfer robot 312 loaded with wafer # 314 on the wafer transfer arm 312b of the wafer transfer robot 312 is mounted on the wafer transfer arm 312b of the wafer transfer robot 312. The second cassette 210 is moved to the correct position (for example, the position of slot 3).

Subsequently, the wafer transfer robot 310 is left unrotated and rotates only the wafer transfer arm 312b constituting the wafer at an angle of 180 °. In this state, the wafer transfer arm 312b on which wafer 5 is mounted is pushed to the slot 3 position in the second cassette 310 in a horizontal position on a plane. As a result, wafer 5 (314) is transferred to the correct position of the second cassette (310, for example, slot 3).

By repeating the above operation on the remaining 24 wafers 314 loaded in the first cassette 304, the wafer transfer operation is completed.

When the wafer transfer system is designed as in the second and third embodiments, the wafer can be transferred in the shortest distance.

Fig. 9 shows an example of wafer alignment according to the selection of the wafer processing method (ascending / descending / hole, even number / individual selection) in the case of transferring the wafer by applying the wafer transfer system shown in the first to third embodiments. A table is shown.

Referring to the table of FIG. 9, when the wafers are automatically sorted in ascending order, 25 wafers are loaded in such a manner that one wafer is loaded in the first slot of the second cassette and two wafers are loaded in the second slot. On the other hand, when the wafers are automatically sorted in descending order, it can be seen that 25 wafers are loaded in a slot 1 of the second cassette and 25 wafers in a slot 2 of the wafer.

In the case of automatically sorting the wafers in the order of odd and even numbers, one wafer is loaded in slot 1 of the second cassette, three wafers are loaded in slot 2, and five wafers are loaded in slot 3. The odd wafer is loaded, the second wafer is loaded in slot 1, the second wafer is loaded, the second slot is loaded in the fourth wafer, and the third slot is loaded in the sixth wafer. It can be seen that. In addition, if an engineer automatically selects wafers in a manner that allows the wafer to be individually selected, four wafers are loaded into slot 1 of the second cassette, seven wafers into slot 2, and 24 wafers into slot 3. It can be seen that 25 wafers are loaded.

As such, in order to automatically arrange wafers sequentially, the process inspection work is performed by an engineer artificially inspecting only a few wafers corresponding to the weak point, without having to inspect all the individual wafers during the process inspection work performed at every unit process. Since it may be carried out, the time loss required during the process inspection work can be reduced.

As described above, according to the present invention, the wafers are sorted sequentially (ascending / descending / hole, even / individual selection) according to the specified wafer processing method every time a unit process is performed in manufacturing a semiconductor device. 1) It can cope with the necessity of individual management of large-diameter wafers, and it is possible to computerize individual wafers. 2) It is possible to analyze the process characteristics of each unit process. 4) Since the wafers are automatically arranged by the sequential reference alignment method even in the repeated process, it is possible to clearly verify the process characteristic change according to the continuity of the step-by-step process.

Claims (68)

System body, A cassette holder mounted to a predetermined portion on the system body; A first cassette mounted on the cassette holder and loaded with a plurality of wafers; A unique number retrieval apparatus mounted on one side of the first body of the first cassette and designed to enable linear movement in up and down directions; A cassette moving table mounted on the system body at a point spaced apart from the unique number retrieval device and designed to enable linear movements up and down; A second cassette mounted on the cassette carrier, the wafer being unloaded; And a wafer transfer robot mounted on the system body on the other side of the first cassette, the wafer transfer robot being designed to enable up / down linear movement. The wafer transfer system of claim 1, wherein the unique number retrieval device has a height of 40 to 50 cm. The wafer transfer system of claim 1, wherein the unique number retrieval device comprises a support mounted on the system body and a letter recognition unit attached to a predetermined portion of one side of the support. The wafer transfer system of claim 3, wherein the character recognition unit is fixed to be inclined at an angle of 45 ° with respect to a horizontal plane on which the wafer is placed. The wafer transfer system of claim 1, wherein the wafer transfer robot comprises a support mounted on the system body, and a wafer transfer arm disposed on the support, on which the wafer is mounted. The wafer transfer system of claim 5, wherein the wafer transfer arm is designed to enable left / right linear movement. The wafer transfer system of claim 5, wherein the wafer transfer arm has a length of 33 to 37 cm. The wafer transfer system of claim 5, wherein the support has a height of 28 to 30 cm. The wafer transfer system of claim 1, wherein the wafer transfer system of the semiconductor fabrication facility is networked with a computer. The wafer transfer system of claim 1, wherein the first and second cassettes are disposed at positions corresponding to each other on the system body. System body, First and second cassette holders mounted on the system body so as to be spaced apart from each other by a predetermined distance; A first cassette mounted on the first cassette holder and loaded with a plurality of wafers; A second cassette mounted on the second cassette holder, the wafer being unloaded; A wafer transfer robot mounted on the system body between the first cassette and the second cassette, the wafer transfer robot being designed to enable up / down linear motion and rotational motion; And a unique number retrieval device mounted on the system body between the wafer transfer robot and the first cassette and designed to allow up / down linear movement. The wafer transfer system of claim 11, wherein the wafer transfer robot is designed to rotate 180 °. The wafer transfer system of claim 11, wherein the unique number retrieval device has a height of 40 to 50 cm. The wafer transfer system of claim 11, wherein the unique number retrieval device comprises a support mounted on the system body and a letter recognition unit attached to a predetermined portion of one side of the support. The wafer transfer system of claim 14, wherein the character recognition unit is fixed to be inclined at an angle of 45 ° with respect to a horizontal plane on which the wafer is placed. The wafer transfer system of claim 11, wherein the wafer transfer robot comprises a support mounted on the system body, and a wafer transfer arm disposed on the support, on which the wafer is mounted. The wafer transfer system of claim 16, wherein the wafer transfer arm is designed to enable left / right linear movement. The wafer transfer system of claim 16, wherein the wafer transfer arm has a length of 22 to 24 cm. The wafer transfer system of claim 16, wherein the support has a height of 28 to 30 cm. The wafer transfer system of claim 11, wherein the first and second cassettes are disposed at positions corresponding to each other on the system body. 12. The wafer transfer system of claim 11 wherein the wafer transfer system of the semiconductor fabrication facility is networked with a computer. System body, First and second cassette holders mounted on the system body so as to be spaced apart from each other by a predetermined distance; A first cassette mounted on the first cassette holder and loaded with a plurality of wafers; A second cassette mounted on the second cassette holder, the wafer being unloaded; A wafer transfer robot mounted on the system body between the first cassette and the second cassette, the wafer transfer robot being designed to allow up / down linear motion; And a unique number retrieval device mounted on the system body between the wafer transfer robot and the first cassette and designed to allow up / down linear movement. 23. The wafer transfer system of claim 22, wherein the wafer transfer robot comprises a support mounted on the system body, and a wafer transfer arm disposed on the support, on which the wafer is mounted. 24. The wafer transfer system of claim 23, wherein the wafer transfer arm is designed to enable left / right linear motion and rotational motion. 25. The wafer transfer system of claim 24 wherein the wafer transfer arm is designed to rotate 180 [deg.]. 25. The wafer transfer system of claim 24 wherein the wafer transfer arm has a length of 22 to 24 cm. 24. The wafer transport system of claim 23, wherein the support has a height of 28-30 cm. The wafer transfer system of claim 22, wherein the unique number retrieval device has a height of 40 to 50 cm. 23. The wafer transfer system of claim 22, wherein the unique number retrieval device comprises a support mounted on the system body and a letter recognition unit attached to a predetermined portion of one side of the support. 30. The wafer transfer system of claim 29, wherein the character recognition unit is fixed to be inclined at an angle of 45 degrees with respect to the horizontal plane on which the wafer is placed. 23. The wafer transport system of claim 22, wherein the first and second cassettes are disposed at positions corresponding to each other on the system body. 23. The wafer transfer system of claim 22 wherein the wafer transfer system of the semiconductor fabrication facility is networked with a computer. System body, First to third cassette holders mounted on the system body so as to be spaced apart from each other by a predetermined distance; A first cassette mounted on the first cassette holder and loaded with a plurality of wafers; Second and third cassettes mounted on the second and third cassette holders and unloaded wafers; A wafer transfer robot mounted on the system body between the first cassette and the second cassette, the wafer transfer robot being designed to enable up / down linear motion and rotational motion; And a unique number retrieval device mounted on the system body between the wafer transfer robot and the first cassette and designed to allow up / down linear movement. 34. The method of claim 33, wherein the first and second cassettes are disposed at positions corresponding to each other, and the third cassette is disposed on a line extending in the vertical direction at the center of the first and second cassettes. Wafer Transfer System in Semiconductor Manufacturing Equipment. 35. The wafer transfer system according to claim 34, wherein the first to third cassettes are arranged to be equally spaced from each other from a central portion of the first and second cassettes. 34. The wafer transfer system of claim 33, wherein the wafer transfer robot is rotated at an angle selected from 90 [deg.] Or 180 [deg.]. 34. The wafer transfer system of claim 33, wherein the unique number retrieval device has a height of 40 to 50 cm. 34. The wafer transfer system of claim 33, wherein the unique number retrieval device comprises a support mounted on the system body and a letter recognition unit attached to a predetermined portion of one side of the support. 39. The wafer transfer system of claim 38, wherein the character recognition unit is fixed to be inclined at an angle of 45 [deg.] With respect to a horizontal plane on which the wafer is placed. 34. The wafer transfer system of claim 33, wherein the wafer transfer robot comprises a support mounted on the system body and a wafer transfer arm disposed on the support and on which the wafer is mounted. 41. The wafer transfer system of claim 40 wherein the wafer transfer arm is designed to allow left / right linear motion. 41. The wafer transfer system of claim 40 wherein the wafer transfer arm has a length of 22 to 24 cm. 41. The wafer transport system of claim 40, wherein the support has a height of 28-30 cm. 34. The wafer transfer system of claim 33, wherein the wafer transfer system of the semiconductor fabrication facility is networked with a computer. System body, First to third cassette holders mounted on the system body so as to be spaced apart from each other by a predetermined distance; A first cassette mounted on the first cassette holder and loaded with a plurality of wafers; Second and third cassettes mounted on the second and third cassette holders and unloaded wafers; A wafer transfer robot mounted on the system body between the first cassette and the second cassette, the wafer transfer robot being designed to allow up / down linear motion; And a unique number retrieval device mounted on the system body between the wafer transfer robot and the first cassette and designed to allow up / down linear movement. 46. The wafer transfer system of claim 45, wherein the wafer transfer robot comprises a support mounted on the system body and a wafer transfer arm disposed on the support and on which the wafer is mounted. 47. The wafer transfer system of claim 46, wherein the wafer transfer arm is designed to enable left / right linear and rotational movements. The wafer transfer system of claim 46, wherein the wafer transfer arm is rotated at an angle selected from 90 ° or 180 °. 47. The wafer transfer system of claim 46 wherein the wafer transfer arm has a length of 22 to 24 cm. 47. The wafer transport system of claim 46, wherein the support has a height of 28-30 cm. 46. The wafer transport system of claim 45, wherein said unique number retrieval device has a height of 40-50 cm. 46. The wafer transfer system of claim 45, wherein the unique number retrieval device comprises a support mounted on the system body and a letter recognition unit attached to a predetermined portion of one side of the support. The wafer transfer system of claim 52, wherein the character recognition unit is fixed to be inclined at an angle of 45 ° with respect to a horizontal plane on which the wafer is placed. 46. The apparatus of claim 45, wherein the first and second cassettes are disposed at positions corresponding to each other, and the third cassette is disposed on a line extending in the vertical direction at the center of the first and second cassettes. Wafer Transfer System in Semiconductor Manufacturing Equipment. 55. The wafer transport system of claim 54, wherein the first to third cassettes are arranged to be equally spaced from each other from a central portion of the first and second cassettes. 46. The wafer transfer system of claim 45, wherein the wafer transfer system of the semiconductor fabrication facility is networked with a computer. A first step of retrieving the unique numbers of the plurality of wafers loaded in the first cassette using a unique number retrieval device and displaying the results on a computer screen; A second step of designating a wafer processing method based on array selection criteria set in the computer, and Using a wafer transfer robot, a third step of sequentially loading a plurality of wafers in the first cassette into position in a second cassette in which the wafers are unloaded by the wafer processing method specified in the second step, The third step includes mounting any wafer in the first cassette to a wafer transfer arm of a wafer transfer robot; Based on a designated wafer processing method, linearly moving the cassette carrier on which the second cassette is mounted by a predetermined height; And loading the wafer mounted on the wafer transfer arm into a second cassette mounted on the cassette moving object. 59. The method of claim 57, wherein the wafer processing method is set to be divided into descending order, ascending order, and individual selection. 59. The method of claim 57, wherein in the first step, the unique number retrieval apparatus retrieves the unique number of the wafer in a scanning manner through a character recognition unit of the unique number retrieval apparatus. 59. The method of claim 57, wherein the wafer transfer method of the wafer transfer system further includes the step of checking the number of wafer loads in the first cassette before the first step. A first step of retrieving the unique numbers of the plurality of wafers loaded in the first cassette using a unique number retrieval device and displaying the results on a computer screen; A second step of designating a wafer processing method based on array selection criteria set in the computer, and Using a wafer transfer robot, a third step of sequentially loading a plurality of wafers in the first cassette into a second position in which the wafer is unloaded by a wafer processing method designated in the second step, The third step includes the step of mounting any wafer in the first cassette to the wafer transfer arm of the wafer transfer robot; Moving the wafer transfer robot to a home position of the second cassette based on a designated wafer processing method; Rotating the wafer transfer robot by a predetermined angle; And, And loading the wafer mounted on the wafer transfer arm into the second cassette. 62. The method of claim 61, wherein the wafer transfer robot rotates 180 degrees. A first step of retrieving the unique numbers of the plurality of wafers loaded in the first cassette using a unique number retrieval device and displaying the results on a computer screen; A second step of designating a wafer processing method based on an array selection criterion set in the computer; Using a wafer transfer robot, a third step of sequentially loading the plurality of wafers in the first cassette into the second cassette and the third cassette in position by the wafer processing method designated in the second step, The third step includes the step of mounting any wafer in the first cassette to the wafer transfer arm of the wafer transfer robot; Moving the wafer transfer robot to a correct position of any one of the second cassette and the third cassette according to a designated wafer processing method; Rotating the wafer transfer robot by a predetermined angle toward a selected cassette; And, And loading the wafer mounted on the wafer transfer arm into a selected cassette. 64. The method of claim 63, wherein the wafer processing method is set to be divided into odd, even and individual selections. 64. The method of claim 63, wherein the wafer transfer robot rotates 180 [deg.] When the second cassette is selected. 64. The method of claim 63, wherein the wafer transfer robot rotates by 90 [deg.] When the third cassette is selected. 64. The method of claim 63, wherein in the first step, the unique number retrieval apparatus retrieves the unique number of the wafer in a scanning manner through a character recognition unit of the unique number retrieval apparatus. 64. The method of claim 63, wherein the wafer transfer method of the wafer transfer system further comprises the step of checking the number of wafer loads in the first cassette before the first step.

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