KR20040040625A - Method and system for controlling wafer of photo spinner - Google Patents

Abstract

PURPOSE: A wafer maintenance method and system of a photo spinner are provided to be capable of restraining the bridge or CD(Critical Dimension) failure of a photoresist layer coated on a wafer due to equipment reactivation. CONSTITUTION: Equipment is stopped according to the generation of alarm while a photoresist coating process is performed on a wafer(21,23). The equipment is reactivated when completing the steps according to the alarm(25,27). The stand-by time of the wafer in the equipment is calculated and stored(29). Whether the stand-by time exceeds a maximum stand-by time is decided(31). When the stand-by time exceeds the maximum stand-by time, stand-by alarm is generated(33). The wafer corresponding to the stand-by alarm is separated from the equipment and a re-treatment is performed on the wafer(35,37).

Description

Method and system for controlling wafer of photo spinner

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photo spinner, and more particularly, to a method and a system for managing a wafer of a photo spinner, which can suppress process defects caused when a wafer is stopped for a predetermined time in a facility.

A semiconductor device is formed by three-dimensionally stacking a plurality of desired film qualities on a wafer. In this case, a film having a desired shape is formed on the wafer, or a mask for selectively removing the film formed on the wafer is formed on the wafer, which is typically a photo mask using a photoresist. ), And a process of forming and removing such a photo mask is called a lithography step.

Therefore, a photo process is a process of forming a photo mask by applying and developing a photoresist on a wafer to form a film-like pattern of a desired shape on the wafer, and removing the photo mask after forming a pattern of a desired shape. It includes. The photoresist has a composition in which an additive is added to three basic elements of a solvent, a polymer, and a sensitizer. Polymers are light-sensitive polymer compounds dissolved in solvents and are the key constituents of photoresists. Solvent is a component that allows the photoresist to be applied in the form of an extremely thin film on the wafer, which is then evaporated by a curing process after the photoresist is applied on the wafer to a certain thickness. Sensitizers control and modify the chemical properties of the photoresist.

In the photolithography process, a spin coating method is generally used to form a photoresist on a wafer with a predetermined thickness, and a device used in the spin coating method is called a photo spinner.

When the photoresist coating process is performed by using a photo spinner (hereinafter, referred to as a "spinner"), the process may be temporarily suspended due to a process problem. As shown in FIG. The photo spinner will work. That is, if a functional problem occurs during the process, an equipment alarm is generated (12), and the equipment is next stopped (14). And the equipment continues to stop until the completion of the action according to the facility alarm, and when the alarm action is completed (16) restarts the facility (18) to proceed the process again (19).

In the related art, wafers are stagnated in the facility until the facility is restarted after the facility is stopped, but the stagnant wafers are put into the process after the facility is restarted. Therefore, if the wafer is stagnated for more than a predetermined time due to the equipment stop during the photoresist coating process, a bridge defect or a CD (critical dimension) defect is caused by the photoresist already coated on the wafer, resulting in a poor photoresist coating process. It is connected immediately.

Therefore, an object of the present invention is to be able to suppress the bridge failure or CD failure of the photoresist coated on the wafer due to restarting the facility after the facility is stopped.

Another object of the present invention is to manage the history of the wafers to be restarted after the facility is stopped to quickly respond to the photoresist coating process failure.

1 is a flowchart illustrating an operation of a photo spinner according to the related art according to an alarm.

2 is a block diagram showing a wafer management system of a photo spinner according to the present invention.

3 is an operational flowchart of a photo spinner according to the present invention for wafer management in response to an alarm.

4 is a diagram illustrating a delay time explanation screen of a photo spinner displayed on a display unit.

FIG. 5 is a diagram illustrating a screen for displaying a congested lot information database of a photo spinner displayed on a display unit.

FIG. 6 is a diagram illustrating a screen displayed on the display unit when a lot ID is clicked in FIG. 4.

Description of the main parts of the drawing

40: wafer management system 41: coating

43: facility alarm 45: congestion alarm

47: display unit 49: control unit

In order to achieve the above object, a method of managing a wafer of a photo spinner, the method comprising the steps of: (a) stopping the facility in accordance with the facility alarm during the photoresist coating process for the wafer using the photo spinner; (b) restarting the facility when the action according to the facility alert is complete; (c) calculating the retention time of the wafer stagnant in the facility from the facility shutdown to restarting the facility and storing the retention time; (d) determining whether the retention time has exceeded a set maximum retention time and generating a wafer retention alarm if exceeded; And (e) separating and reprocessing the wafer from which the wafer congestion alarm has occurred in the facility.

In the step (d) according to the present invention, if the retention time does not exceed the maximum retention time, the photoresist coating process is performed again.

And after step (d) according to the present invention, displaying information on the wafer whose retention time exceeds the maximum retention time for the operator to confirm.

The present invention also provides a wafer management system for photo spinners. That is, the coating unit is a photoresist coating process for the supplied wafer; A facility alarm unit for generating a facility alarm when a defect occurs during the photoresist coating process in the coating unit; A congestion alarm unit for alarming whether the wafer is congested in the coating unit according to an alarm occurrence of the facility alarm unit; A display unit which displays information on the wafer undergoing the photoresist coating process; And managing the operation of the coating unit, facility alarm unit, congestion alarm unit, and display unit, and including information on a maximum retention time at which wafers in the coating unit can be stagnated, and restarting the facility after an alarm occurs in the facility alarm unit. It provides a wafer management system of a photo spinner comprising a; control unit for generating a stall alarm by calculating the stall time by calculating the stall time and the stall time exceeds the maximum stall time. .

In addition, the controller according to the present invention displays information on the wafer for which the maximum retention time has been exceeded.

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

2 is a block diagram showing a wafer management system 40 of a photo spinner in accordance with the present invention. Referring to FIG. 2, the wafer management system 40 includes a coating part 41, a facility alarm part 43, a congestion alarm part 45, a display part 47, and a control part 49.

The coating part 41 is a portion in which a photoresist coating process is performed on a supplied wafer, and includes a process of applying a photoresist to a wafer by spin coating and curing a spin coated photoresist.

The facility warning part 43 is a part which raises a facility warning, when a process cannot continue because of a problem with the function of a facility during the photoresist coating process in the coating part 41. FIG.

The stagnation alarm part 45 is a part which alerts whether the wafer in the coating part 41 is stagnant according to the facility alarm occurrence of the facility alarm part 43. As will be described later, the congestion alarm unit 45 takes a long time to take action after the facility alarm occurs, and when the wafer retention time in the coating unit 41 becomes long, it serves to prevent process defects in subsequent processes. In charge.

The display unit 47 displays information about the wafer undergoing the photoresist coating process.

The controller 49 manages the operation of the photo spinner including the coating part 41, the facility alarm part 43, the congestion alarm part 45, and the display part 47. In particular, the control unit 49 embeds information on the maximum retention time that the wafer in the coating unit 41 can be stagnated, and calculates the equipment down time from the alarm of the facility warning unit 43 to the restart of the facility. When the equipment stop time exceeds the maximum stall time, the stall alarm 45 is driven to generate a stall alarm. The controller 49 displays information on the wafer for which the maximum retention time has been exceeded on the display unit 47 to enable the operator to quickly take action on the wafer for which the stagnation alarm has occurred. In addition, the controller 49 stores information about the wafers undergoing the photoresist coating process on a per-lot basis, thereby enabling quick padback to the problem analysis and equipment when quality problems occur in the photoresist coating process. .

An operation flow chart 30 of a photo spinner is shown in FIG. 3 in the wafer management method of the wafer management system 100 of the photo spinner according to the present invention.

Referring to FIG. 2 and FIG. 3, in the situation where the photoresist coating process is smoothly performed in the coating part 41, when the process cannot be continued due to a problem in the facility, the facility warning part ( 43 generates a facility alert (21).

If a facility alert occurs, the facility will stop until the action for the alert is complete (23).

When the action for the facility alarm is completed (25), the facility is restarted (27). In this case, the process was performed by putting the wafer stagnated in the coating unit as it is after the facility restart in the process as it is. In the present invention, the wafer may be continued in consideration of the wafer retention time in the coating unit 41 according to the facility warning. It will decide whether to reprocess the.

First, the control unit 49 stores and calculates the stagnant wafer information when the facility is restarted (29). In other words, the control unit 49 calculates the facility downtime from the facility warning to the facility restart. Next, it is determined whether the equipment stop time exceeds the maximum stagnation time (31). If the maximum stagnation time is not exceeded, the stagnant wafer is put into the coating part 41 as it is and the photoresist coating process is performed. (39). However, when the maximum stall time is exceeded, the stall alarm 45 is driven to generate a stall alarm (35).

When the congestion alarm is generated, the display unit 47 displays information on the wafer for which the maximum congestion time has been exceeded, allowing the operator to quickly take action on the wafer on which the congestion alarm has occurred (35).

After checking the wafer in which the congestion alarm has occurred, the operator determines whether the wafer in the coating part 41 is reprocessed (37). That is, when the wafer needs to be reprocessed, the wafer is removed from the coating part 41 so that the photoresist coating process can be performed (39), and the wafer removed from the coating part 41 is reprocessed. Is committed. If the operator determines that the wafer does not need to be reprocessed, the photoresist coating process may be performed (39).

Meanwhile, the display unit 41 displays a screen as illustrated in FIGS. 4 to 6. Referring to FIG. 4, in order to generate a congestion alarm during wafer congestion, an operator may display a display unit to set and change a maximum retention time for each unit. On the other hand, "UNIT NAME" indicates a part where the wafer is formed by the photoresist coating process for the wafer in the coating portion. "Set up stagnation time" is the part that can set the maximum stagnation time for each uni, because the quality problem occurs by each unit due to equipment stop. In addition, "ALARM occurrence / non-setting" is the part that sets the alarm occurrence when the equipment stop time has passed the value of "Set time setting" (Maximum stall time). In this case, it can be set as "occurrence" when it has a significant impact on quality, and as "non-occurrence" when it does not have a significant influence.

Referring to FIG. 5, a screen displaying a lot lot information database of a photo spinner displayed on a display unit is shown. The screen displaying the congested lot information database displays "LOT ID", "progress time", and the status of congested ALARM. If the details of the "LOT ID" are clicked, the "contained lot information by each lot" as shown in FIG. HISTORY "is displayed. That is," LOT ID "is an identification tag for identifying wafer carriers loaded with wafers to be entered into the process, and" SLOT NO "is indicated by a specific LOT ID creek for wafers in the wafer carrier. , Information on the " static unit ", retention time " and " ALARM " for the wafers loaded in the wafer carrier is displayed.

For example, if "LOT ID: 7GG547.1" is clicked on the display screen of FIG. 5, the congestion information of the wafers loaded in the wafer carrier corresponding to "LOT ID: 7GG547.1" is shown in FIG. 6. Is displayed.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to aid understanding and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is apparent to those skilled in the art that other modifications based on the technical idea of the present invention may be implemented.

Therefore, according to the present invention, after the equipment is stopped, the equipment downtime is calculated according to the equipment restart, and it is determined whether the calculated equipment downtime exceeds the set maximum stall time, thereby reprocessing the wafer having exceeded the maximum stall time. Since the process proceeds, it is possible to suppress the photoresist coating process defect caused by restarting the facility after the facility is stopped.

By managing the history of wafers that are put into restarting equipment after the equipment is stopped, when the photoresist coating process defect occurs, the cause analysis and response to the photoresist coating process defect can be promptly performed.

Claims (5)

In the wafer management method of the photo spinner, (a) stopping the facility in accordance with facility warnings during the photoresist coating process for the wafer using the photopinner; (b) restarting the facility when the action according to the facility alert is complete; (c) calculating the retention time of the wafer stagnant in the facility from the facility shutdown to restarting the facility and storing the retention time; (d) determining whether the retention time has exceeded a set maximum retention time and generating a wafer retention alarm if exceeded; And (e) separating and reprocessing the wafer from which the wafer congestion alarm has occurred in the facility; and managing the wafer of the photo spinner. The method of claim 1, wherein in the step (d), when the retention time does not exceed the maximum retention time, the photoresist coating process is performed again. The wafer of claim 1, further comprising, after step (d), displaying information on the wafer whose retention time exceeds the maximum retention time for the operator to confirm. How to manage. A coating part on which a photoresist coating process is performed on the supplied wafer; A facility alarm unit for generating a facility alarm when a defect occurs during the photoresist coating process in the coating unit; A congestion alarm unit for alarming whether the wafer is congested in the coating unit according to an alarm occurrence of the facility alarm unit; A display unit which displays information on the wafer undergoing the photoresist coating process; And It manages the operation of the coating unit, facility alarm unit, congestion alarm unit and display unit, and includes information on the maximum stagnation time that the wafer in the coating can be stagnated, until the facility restart after the alarm occurrence of the facility alarm unit And a control unit for generating a stall alarm by calculating the stall time and driving the stall alarm when the facility stop time exceeds the maximum stall time. 5. The wafer management system of claim 4, wherein the control unit displays information on the wafer whose maximum stagnation time has been exceeded on the display unit.