JP6287048B2 - Substrate transfer method - Google Patents

Description

  The present invention relates to an EFEM (Equipment front end module, hereinafter referred to as EFEM) system that is used when a wafer is transferred between a sealed transfer container called a pod and a semiconductor processing apparatus in a semiconductor manufacturing process or the like. More specifically, the present invention relates to a substrate transfer method for removing a substrate from a pod in the EFEM system and transferring a wafer between the pod and the semiconductor processing apparatus.

  In the semiconductor manufacturing process, the so-called yield in the process is improved by highly cleaning the inside of the pod that accommodates the wafer and the inside of the minute space in which the wafer is inserted into and removed from the pod and delivered to each processing apparatus. ing. However, along with the narrowing of the wiring width accompanying the change in the semiconductor design rule, it is necessary to review the so-called cleanliness at a level that has not been a problem in the micro space. For example, the allowable size is smaller with respect to the size of dust and the like, but in order to remove this and supply the external gas to the minute space, it is necessary to use a filter with a larger load on the fan. Patent Document 1 discloses a technique for reducing the load on the fan-filter unit in such a situation by circulating a gas controlled to a sufficient cleanliness.

JP 2007-003069 A

  The pod containing the wafer is closed with the purge gas and the like managed at the time of wafer insertion sealed. However, there is a possibility that the atmosphere in the pod is deteriorated more cleanly than the situation when the lid is closed, such as generation of dust due to vibration, while waiting for processing or transporting between apparatuses. In this case, when the wafer is taken out from the pod, the atmosphere in the pod may cause so-called contamination in a minute space when further fine wiring is formed.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a pod lid opening / closing method that reduces the possibility of contamination in a minute space even when the pod lid is opened.

In order to solve the above-described problems, a substrate transport method according to the present invention is based on a pod that accommodates a substrate therein, and a substrate inside a minute space having an opening that can be opened and closed by a door while the atmosphere is controlled inside A step of placing the pod on a placement table disposed in front of the opening, and a step of supplying a gas managed inside the pod in the placement state, The step of adjusting the atmosphere inside the pod by supplying gas, the step of opening the pod after adjusting the atmosphere inside the pod and communicating the inside of the pod with the inside of the minute space, air body in which a step of transporting the substrate inside, Ru is supplied into the pod has a space is supplied to the interior of the pod through the temperature control device disposed in the supply path for supplying gas to the interior of the pod It is, the minute the sky Characterized in that it is managed in the temperature for the feed gas corresponding to the set temperature in order to manage the internal atmosphere, by the management parameters including.

In the substrate transport method described above, the management parameters for managing the atmosphere inside the minute space each have a set allowable limit value, and the management parameter for the atmosphere inside the pod is the allowable limit for the supply of the managed gas. It is preferable to carry out until it falls below the value. Further, in the substrate transport method, in the process of supplying the controlled gas to the inside of the pod, the gas is placed on the top surface of the mounting table so as to correspond to the pod side nozzle and the pod side nozzle arranged on the bottom surface of the pod. It is preferable that it is made via the mounting table side nozzle arrange | positioned. Further, the substrate transporting method has a step of circulating the atmosphere inside the minute space into which the gas supplied into the pod has flowed, and the atmosphere inside the minute space is managed in the step of circulating. More preferably. The management parameters may even include those relating to dust encompassed by the atmosphere in the minute space, including those related to oxygen concentration even better, it may include those relating to moisture in the atmosphere.

  According to the present invention, even when the lid of the pod is opened, the environment in the minute space can be maintained in a so-called clean state and can be applied to a process for forming finer wiring.

It is a figure which shows schematic structure of the EFEM system suitable for implementation of the board | substrate conveyance method which concerns on one Embodiment of this invention. It is a figure which shows the board | substrate conveyance method which concerns on one Embodiment of this invention as a flowchart. It is a figure which shows the external appearance image of what implemented the EFEM system shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of an EFEM system suitable for carrying out a substrate carrying method according to an embodiment of the present invention. The EFEM system 100 includes an EFEM unit 101, a housing 103, a door 105, a mounting table 107, and a transfer robot 109. The housing 103 defines an EFEM unit 101 that is a minute space inside, and has an opening 104 corresponding to a position where the mounting table 107 is disposed. The opening 104 can be opened and closed by a door 105. A pod 110 can be mounted on the mounting table 107.

  The pod 110 is disposed on the bottom surface of a housing space for housing a semiconductor substrate (not shown) and the like, and can supply or discharge gas from the outside to the atmosphere in the housing space. And a pod-side nozzle 111. The pod 110 has an opening that is closed by a lid (not shown). By removing the lid, the substrate accommodated in the pod 110 can be inserted and removed through the opening. Removal or attachment of the lid is performed by the door 105.

  The EFEM unit 101 is accompanied by an atmosphere circulation path 102. The atmosphere flowing out or sucked into the atmosphere circulation path 102 from the lower part of the EFEM part 101 reaches the upper part of the EFEM part 101 via the atmosphere circulation path 102 and is supplied again into the EFEM part 101 via the filter unit or the like. . The atmosphere is managed by using dust inclusion amount, oxygen concentration, humidity, atmosphere temperature, and the like as management parameters. In this embodiment, measurement and control of current values of these parameters are executed in the atmosphere circulation path 102. In this embodiment, these parameters are managed by supplying so-called dry nitrogen as an inert gas and the characteristics of the filter used in the fan filter unit. The temperature is also maintained by dry nitrogen supplied.

  The mounting table 107 includes a mounting table side nozzle 113 disposed on the upper surface of the mounting table 107 so as to correspond to the pod side nozzle 111 described above. The mounting table side nozzle 113 is connected to a gas supply path (not shown), and can supply gas into the pod 110 from the gas supply path in cooperation with the pod side nozzle 111. The humidity and purity (oxygen content) of the gas supplied to the gas supply path, that is, dry nitrogen in this embodiment, are managed in advance. Further, the temperature at the time of supplying the pod 110 is also managed by the temperature management device 115. Furthermore, dust and the like are managed by placing specific filters on the mounting table side nozzle 113, the pod side nozzle 111, or both.

  In addition, in the figure, only one pair of the pod side nozzle 111 and the mounting table side nozzle 113 is shown, but other pairs are actually arranged. When the managed gas is supplied into the pod 110 using the previous pair, the excess internal atmosphere is discharged to the external space through the other pair. Further, it is preferable that the current management parameters in the atmosphere in the pod 110 are measured in this exhaust path. However, for example, when the management environment, the time for which the pod is placed, etc. are determined in advance with respect to the conditions until the pod is placed, the atmosphere state can be estimated based on the management table obtained empirically. It is. In this embodiment, from the viewpoint of simplifying the device configuration and reducing the device cost, the management parameters are restored by supplying the managed gas for a predetermined time based on the estimated atmosphere state. It is determined that

  Next, steps for actually transporting the substrate from the pod 110 will be described with reference to the flowchart shown in FIG. In the substrate transfer process of taking out the substrate from the pod 110, first, the pod 110 is placed on the mounting table 107 in step S1. The pod 110 is mounted in a predetermined positional relationship with respect to the mounting table 107 by a positioning configuration such as a positioning pin (not shown). As a result, the pod side nozzle 111 and the mounting table side nozzle 113 are connected (step S2). After confirming that the pod 110 and the mounting table 107 are in a predetermined positional relationship, that is, that both nozzles are connected, in step S3, the controlled gas into the pod 110 via these nozzles. Supply is started.

  The internal atmosphere of the EFEM unit 101 is managed based on the management parameters described above. Further, each of these management parameters is measured, for example, at a predetermined time interval, and it is confirmed whether or not the management parameters are maintained within an allowable range set for each parameter. For example, with respect to oxygen concentration and humidity, when the allowable limit value is exceeded, the above-described dry nitrogen supply is performed, and the value is restored to the allowable range. In step S4, the supply of the managed gas is performed until the management parameters are within the set allowable range for the internal atmosphere of the pod 110. In this embodiment, it is determined that the nuclear control parameter is within the allowable range by the gas supply operation for a predetermined period that is empirically derived from the volume in the pod 110 and the standing time.

  In the present invention, the permissible limit value is a value that defines the permissible range, and that the measured value falls within the permissible range is expressed as falling below the permissible limit value. With regard to the internal atmosphere of the pod 110, regarding the parameters according to the management parameters of the EFEM unit 101, the pod 110 and the EFEM unit 101 are allowed to communicate with each other if the value of each parameter falls below the allowable limit value for the EFEM unit 101. I am going to do that. Specifically, the atmosphere in the pod 110 is replaced with a gas whose cleanness is controlled by a parameter according to the management parameter of the EFEM unit 101, and the cleanliness is temporarily made to conform to the cleanliness of the EFEM unit 101. Then, by connecting these, the possibility that the above-described adverse effects occur can be greatly reduced.

  That is, after the predetermined period has elapsed, the supply of gas is stopped in step S5. Subsequently, in step S6, the lid of the pod 110 is gripped by the door 105 and removed from the pod 110. As a result, communication between the space inside the pod 110 and the EFEM unit 101 is performed. Conventionally, it has been considered that the internal atmospheres having different management states mutually diffuse at this time, and the so-called clean environment may be deteriorated by the internal atmosphere having a poor cleanliness depending on the influence. However, in general, the internal environment of the EFEM unit 101 is always maintained within an allowable range by communicating in a state where each internal atmosphere is sufficiently controlled as in the present invention. Become. After these operations, the substrate is transferred by the transfer robot 109 through the opening-opening that is communicated (step S7).

  Here, in an environment using so-called air in which dust or the like is simply removed, a natural oxide film is formed on the substrate surface or various wirings formed on the substrate. Therefore, by filling the inside of the pod 110 with nitrogen, which is an inert gas, it is possible to suppress the generation of a natural oxide film when the pod 110 is transported. In addition, in order to obtain the same effect during substrate transportation, a configuration in which an inert gas is circulated also in the EFEM unit 101 has been adopted in recent years. However, the degree of sealing in the pod 110 is not so suitable, and the oxygen partial pressure often increases due to leakage or the like over time. For this reason, when the inside of the pod 110 and the EFEM unit 101 are communicated with each other, the oxygen concentration inside the EFEM unit 101 may temporarily exceed the allowable limit value.

  As described above, when a pod having a lowered cleanliness is opened, the internal atmosphere of the EFEM unit 101 is contaminated and an operation for recovering it is necessary. The EFEM unit 101 is spatially large with respect to the internal volume of the pod 110, and a long atmosphere replacement time and a large amount of inert gas are required to reduce the oxygen concentration in this space. As in this embodiment, after the atmosphere in the pod 110 is cleaned in advance, the EFEM unit 101 and the pod 110 are communicated with each other, so that the inside of the EFEM unit 101 can be achieved with a short gas supply time and a small gas supply amount. It is possible to maintain a suitable environment.

(Example)
Next, a case where the above-described EFEM system 100 is embodied will be described with reference to the drawings. FIG. 3 shows an appearance of an example of the EFEM system 100. FIG. 3A shows a state when the EFEM system 100 is viewed from the front, and FIG. 3B shows a state when the EFEM system 100 is viewed from the left side. c) shows a state seen from the right side view, and (d) shows a state seen from the upper surface. In addition, about the same structure as the structure shown with the reference number in embodiment mentioned above, it shows with the same reference number, and the detailed description is abbreviate | omitted here.

  The EFEM system 100 according to the present embodiment includes a control unit 119 in addition to the configuration of the EFEM unit 101 and the mounting table 107 described above. The EFEM unit 101 is defined as a minute space by the housing 103, and as described above, the transfer robot 109 for transferring the substrate to the processing chamber for performing various processes on the substrate as the accommodation in the pod 110 is disposed inside. Has been. The control unit 119 controls the operation of each drive element arranged in the EFEM system 100 or the above-described parameter measurement system and management mechanism. In this example, three mounting tables 107 are arranged, and an opening 104 provided in the housing 103 and a door 105 for closing the opening 104 are also arranged corresponding to the mounting tables. The atmosphere circulation path 102 sucks in the atmosphere from the three EFEM units 101 and supplies the atmosphere to each of them.

  The control unit 119 has a module area that functions as a control unit of a driving unit that controls a driving element such as a motor or an air cylinder. In addition, a measurement signal is obtained from the parameter measurement system, for example, a judgment means for judging whether or not the measurement value is within an allowable range, and a supply amount and a supply time of the management gas for maintaining the management parameter within the allowable range And a module area that functions as a means for controlling parameter management means and the like.

  By mutually operating the above means, it is possible to suitably execute each step of the substrate transport method described above. In other words, even when the lid of the pod that may have deteriorated the internal atmosphere is opened, the environment in the minute space can be maintained in a so-called clean state, and a process for forming finer wiring. And the EFEM unit can be transported quickly.

  As described above, the present invention relates to an EFEM system suitably used for a semiconductor processing apparatus. However, the applicability of the present invention is not limited only to the processing apparatus. For example, a processing apparatus that handles a panel of a liquid crystal display, etc., for an EFEM system used in various processing apparatuses that perform various processes according to semiconductors. Is applicable.

  Further, the present invention supplies software (program) for realizing the functions of the above-described embodiments to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus. The processing for reading and executing the program is also included as one form.

DESCRIPTION OF SYMBOLS 100: EFEM system, 101: EFEM part, 103: Housing | casing, 104: Opening part, 105: Door, 107: Mounting stand, 109: Transfer robot, 110: Pod, 111: Pod side nozzle, 113: Mounting base side Nozzle, 115: Temperature management device, 119: Control unit

Claims (7)

A substrate transport method for transporting the substrate into a minute space having an opening that can be opened and closed by a door, the atmosphere of the interior being controlled from a pod that accommodates the substrate inside,
Mounting the pod on a mounting table disposed in front of the opening;
Supplying a controlled gas inside the pod in a mounted state;
Adjusting the atmosphere inside the pod by supplying the gas;
Opening the pod after adjusting the atmosphere inside the pod and communicating the inside of the pod and the inside of the micro space; and
Transporting the substrate from the inside of the pod to the inside of the minute space, and the gas supplied to the inside of the pod is disposed in a supply path for supplying the gas to the inside of the pod. The temperature is controlled by management parameters including a temperature for a supply gas supplied to the inside of the pod via a temperature management device and corresponding to a temperature set for managing the atmosphere inside the micro space. Substrate transport method.   The management parameters for managing the atmosphere inside the minute space each have a set allowable limit value, and the supply of the managed gas is such that the management parameter for the atmosphere inside the pod is below the allowable limit value. The substrate transfer method according to claim 1, wherein:   In the step of supplying the controlled gas to the inside of the pod, the gas is arranged on the upper surface of the mounting table according to the pod-side nozzle arranged on the bottom surface of the pod and the pod-side nozzle. The substrate transfer method according to claim 1, wherein the substrate transfer method is performed via a side nozzle. The method includes a step of circulating the atmosphere inside the minute space into which the gas supplied into the pod flows, and the atmosphere inside the minute space is managed in the step of circulating. The substrate carrying method according to any one of claims 1 to 3. 5. The substrate transfer method according to claim 1, wherein the management parameter includes a dust related to an atmosphere contained in the minute space. The management parameters substrate transfer method according to any one of claims 1 to 5, characterized in that it comprises a related oxygen concentration in the atmosphere inside the minute space. The management parameters substrate transfer method according to any one of claims 1 to 6, characterized in that it comprises a related humidity in the atmosphere of the interior of the minute space.

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