SUBSTRATE PROCESSING APPARATUS, METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE, AND RECORDING MEDIUM

There is provided a technique that includes a processor configured to be capable of executing a process recipe to process a substrate; and a pressure controller configured to be capable of controlling a pressure of a process chamber, in which the substrate is processed, by adjusting an opening degree of a pressure regulating valve provided to an exhaust line of the process chamber, wherein when controlling the pressure of the process chamber, the pressure controller adjusts the opening degree of the pressure regulating valve and outputs information of the opening degree, and wherein while receiving the information of the opening degree from the pressure controller and monitoring an open/close state of the pressure regulating valve, the processor is configured to, when the information of the opening degree is a preset value, be capable of determining whether or not opening/closing of the pressure regulating valve happens.

TECHNICAL FIELD

The present disclosure relates to a substrate processing apparatus, a method of manufacturing a semiconductor device, and a recording medium.

BACKGROUND

As a method of determining the replacement time of a pressure control valve such as an APC (Auto Pressure Controller) valve, for example, a technique for determining the valve replacement time based on the number-of-times of opening/closing a pressure control valve is known in the related art. According to this technique, the valve can be replaced in advance before a threshold value is reached (before failure), but the time for stopping an apparatus due to the maintenance time may increase. Further, for example, the valve replacement time may be determined based on the number-of-times of fully opening/fully closing a valve (FULL OPEN/FULL CLOSE). In this case, because valve operations (during automatic pressure control, etc.) other than full opening/full closing of a valve (FULL OPEN/FULL CLOSE) may not be counted as the number-of-times, the count number may not be accurate. Therefore, there is a possibility that the number-of-times of valve opening/closing and the number of counts are different from each other when a failure occurs. Therefore, for example, there is a possibility that the pressure control valve is replaced after it fails during film formation.

SUMMARY

Some embodiments of the present disclosure provide a technique capable of knowing in advance a criterion for the timing of replacement of a pressure control valve.

According to one embodiment of the present disclosure, there is provided a technique that includes a processor configured to be capable of executing a process recipe to process a substrate; and a pressure controller configured to be capable of controlling a pressure of a process chamber, in which the substrate is processed, by adjusting an opening degree of a pressure regulating valve provided to an exhaust line of the process chamber, wherein when controlling the pressure of the process chamber, the pressure controller adjusts the opening degree of the pressure regulating valve and outputs information of the opening degree to the processor, and wherein while receiving the information of the opening degree from the pressure controller and monitoring an open/close state of the pressure regulating valve, the processor is configured to, when the information of the opening degree is a preset value, be capable of determining whether or not opening/closing of the pressure regulating valve happens, based on the information of the opening degree being monitored and a predetermined threshold value larger than the preset value.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, in the following description, the same constituent elements are denoted by the same reference numerals, and explanation thereof may not be described.

A configuration of a substrate processing apparatus according to an embodiment of the present disclosure is described with reference toFIG. 1.

As shown inFIG. 1, a reaction tube1of the substrate processing apparatus100in the embodiment is installed to be erected on a furnace opening flange2, and an inner tube3is supported to be concentric with the reaction tube1on the furnace opening flange2. Further, a cylindrical heater4is provided to surround the reaction tube1. A reaction furnace includes the heater4, the reaction tube1, and the furnace opening flange2.

An interior of the reaction tube1is an airtight process chamber5, the process chamber5is in fluid communication with an airtight spare chamber6, and the spare chamber6is defined by a transfer housing7that is installed to be continuous to the furnace opening flange2. The transfer housing7is provided with a boat elevator (not shown) as a furnace entering/exiting mechanism, and a boat8as a substrate holder is loaded into and unloaded from the process chamber5by the boat elevator. Further, when the boat8is loaded, the process chamber5is air-tightly closed by a furnace opening cover9.

A gate valve (not shown) is provided in the transfer housing7, a wafer transfer device (not shown) is provided outside the transfer housing7, and the boat8is accommodated in the transfer housing7. In this state, a substrate10such as a wafer is transferred to the boat8via the gate valve by the wafer transfer device.

The furnace opening flange2is in fluid communication with a gas introduction line11to introduce gas into the process chamber5from below the inner tube3, and a gas introduction line12communicates with the spare chamber6. Further, the furnace opening flange2is in fluid communication with an exhaust line13, and the exhaust line13is connected to a vacuum pump23via an APC valve15as a pressure regulating valve.

A pressure detector17is provided to the exhaust line13, and a pressure detection result of the pressure detector17is input to a controller19.

A flow rate controller20is provided to the gas introduction line11, and the flow rate controller20controls a flow rate of the gas supplied from the gas introduction line11to the process chamber5according to a command from the controller19. Further, the flow rate controller20may be configured to be capable of controlling the flow rate of gas supplied from the gas introduction line12to the spare chamber6.

The process chamber5can be put into a vacuum state or a depressurized state by closing the flow rate controller20by the controller19to stop supplying the gas and opening the APC valve15to evacuate the process chamber5by the vacuum pump23.

Further, with the APC valve15opened to evacuate the process chamber5by the vacuum pump23, a pressure detection signal from the pressure detector17is fed back to the controller19, and the controller19controls the flow rate controller20to adjust the flow rate of the introduced gas so that a pressure detected by the pressure detector17becomes a set pressure.

As described above, the pressure of the process chamber5is controlled to a predetermined pressure (for example, the set pressure) by the controller19to control the gas flow rate introduced into the process chamber5and the gas exhaust amount exhausted from the process chamber5. Further, the temperature of the process chamber5is controlled to a predetermined temperature by the controller19to control an amount of heat generation of the heater4. In this operation, an inert gas, for example, a nitrogen gas, may be used as the gas supplied via the gas introduction line11.

With a predetermined number of substrates10charged in the boat8, the boat8is loaded into the process chamber5(boat loading step). Next, the process chamber5is evacuated from an atmospheric pressure and is controlled to a predetermined temperature by being heated by the heater4while being controlled to a predetermined pressure (preparation step). This preparation step may be included in a substrate processing step. Under a predetermined depressurized state and a predetermined temperature maintenance state, a process gas is introduced from the gas introduction line11and is exhausted, and the process gas is supplied to the substrate10, so that wafer processing (substrate processing) such as thin film formation is performed (substrate processing step). When the processing is completed, the boat8is lowered (boat unloading step), and the processed substrate10is discharged. As the thin film, for example, a SiN film (silicon nitride film) is formed.

The APC valve15is configured to be capable of performing and stopping an operation of vacuum exhaust of the process chamber5by opening/closing a valve provided inside in a state where the vacuum pump23is operated, and further to adjust the pressure of the process chamber5by adjusting the valve opening degree based on the pressure information detected by the pressure detector17in a state where the vacuum pump23is operated.

A processor19aincluded in the controller19is configured as a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory) configured as a memory area (work area) in which programs, data, and the like read by the CPU are temporarily stored, a storage device (memory) in which a control program that controls the operation of the substrate processing apparatus100, a process recipe in which procedures and conditions of pressure control, etc. are written, and the like, are readably stored. Here, the data in the memory area is configured to be capable of transferring to the memory at predetermined intervals.

The process recipe functions as a program for causing the processor19ato execute each step in a semiconductor device manufacturing method, to obtain a desired result. Hereinafter, the process recipe and the control program are generally and simply referred to as a “program.” When the term “program” is used herein, it may indicate a case of including the process recipe a case of including the control program, or a case of including both the process recipe and the control program.

A pressure controller19bincluded in the controller19controls the pressure of the process chamber5by adjusting an opening degree of the APC valve15provided to the exhaust line13. In other words, the pressure controller19bsets the pressure of the process chamber5to a predetermined pressure by adjusting the opening degree of the APC valve15, and outputs a monitor value of the valve opening degree as information of the opening degree of the APC valve15to the processor19a. The processor19amonitors an open/close state of the APC valve15by the monitor value while receiving the monitor value of the valve opening degree from the pressure controller19b. For example, the monitor value of the valve opening degree is stored in the memory area of the processor19a. Then, after determining the open/close state of the valve opening, which will be described later, the monitor value of the valve opening degree in the memory area is transferred to the memory or deleted, and the monitor value of the valve opening degree is stored in the memory area of the processor19a.

The processor19acounts the number of times of valve operations of the APC valve15in a region of a certain opening/closing operation amount including “FULL OPEN” and “FULL CLOSE” based on the information of the opening degree of the APC valve15, to thereby detect a criterion for a time of failure of a part, which is not such a part as guaranteed for the durability. This makes it possible to know in advance a criterion timing for valve replacement so that the valve will not be replaced after it breaks down during film forming. The details thereof will be described below.

“FULL CLOSE” indicates 0% openness and “FULL OPEN” indicates 100% openness. The opening/closing (opening degree) of the valve is determined with two threshold values, that is, a lower limit value of the valve opening degree as a first set value and an upper limit value of the valve opening degree as a second set value. These two threshold values (the lower limit value and the upper limit value of the valve opening degree) are preset in the storage device (memory) of the processor19a. However, for the pressure controller19bto control the valve opening degree to reach a target predetermined pressure, for example, it is possible to check a trace value of the valve opening degree as a result of executing a recipe by setting-up or the like and set in the memory the lower limit value and the upper limit value of the valve opening degree, which are used for setting opening degrees deemed as opening and closing of the valve. Here, the lower limit value and the upper limit value of the valve opening degree can be set on a configuration screen displayed by an operator19cincluded in the controller19. The lower limit value of the valve opening degree is greater than 0% and less than 50%, for example, 20%, and the upper limit value of the valve opening degree is greater than 50% and less than 100%, for example, 80%. In addition, when the substrate is being processed in the substrate processing step in the film-forming recipe, the lower limit value of the valve opening degree is determined such that a minute fluctuation value of the valve opening degree during pressure control falls within a range below the lower limit value of the valve opening degree. That is, the opening/closing operation with a small swing width while executing pressure control is set not to be a target for which valve opening/closing is counted. The valve may be operated manually, and the processor19amay collect valve opening degree data even when a recipe is not being executed.

When receiving a monitor value of the valve opening degree of the APC valve15from the pressure controller19b, the processor19amonitors the monitor value of the valve opening degree. For example, as shown inFIG. 2, when the monitor value of the valve opening degree transitions from the lower limit value of the valve opening degree or less to the upper limit value of the valve opening degree or more, and further transitions to the lower limit value of the valve opening degree or less, the processor19acounts up a count value of a number-of-times of valve opening/closing once. In short, the processor19adetermines whether or not valve opening/closing happens when the monitor value of the valve opening degree is the lower limit value of the valve opening degree. At this time, it is checked whether the monitor value of the valve opening degree acquired during monitoring reaches the lower limit value of the valve opening degree after passing through the upper limit value of the valve opening degree. If all the monitor values of the valve opening degree acquired during monitoring are smaller than the upper limit value of the valve opening degree, it is determined that the valve has not been opened/closed. Then, when the determination of an open/close state of the valve opening degree is completed, the monitor value of the valve opening degree monitored so far is cleared, and the monitoring of the valve opening degree is started. Next,FIG. 3is described in more detail. InFIG. 3, when the monitor value of the valve opening degree reaches the lower limit value of the valve opening degree from less than the lower limit value of the valve opening degree, the processor19astarts determining whether valve opening/closing happens or not. In this operation, at a point of time when the monitor value of the valve opening degree transitions from a value more than the upper limit value of the valve opening degree to the lower limit value of the valve opening degree, the processor19adetermines that the valve opening/closing happens, and counts up the number-of-times of opening/closing of the valve. In this way, by monitoring the transition of the monitor value of the valve opening degree acquired from the pressure controller19bwhile the monitor value of the valve opening degree is the valve opening degree lower limit value, the number-of-times of valve opening/closing can be counted more appropriately. In short, the processor19astarts determining whether or not valve opening/closing happens when the monitor value of the valve opening reaches the lower limit value of the valve opening degree, and the processor19astarts counting the number-of-times of valve opening/closing when the monitor value of the valve opening degree reaches the lower limit value of the valve opening degree and the determination of valve opening/closing is completed (when it is determined that the valve opening/closing is performed). Further, the monitoring of the valve opening degree may be started when the valve opening degree is less than the lower limit value, or when the valve is fully closed (the monitoring value of the valve opening degree is 0%).

As in a period (a) inFIG. 3, when the monitor value of the valve opening degree becomes the lower limit value of the valve opening degree or more from less than the lower limit value of the valve opening degree and transitions to the lower limit value of the valve opening degree or less without becoming the upper limit value of the valve opening degree or more, the processor19adetermines that there is no valve opening/closing because the monitor value of the valve opening degree is smaller than the upper limit value of the valve opening degree between the monitor values of the valve opening degree at the lower limit value of the valve opening degree, and does not count up the number-of-times of valve opening/closing. In other words, the processor19adetermines that there is no valve opening/closing when the maximum value of the valve opening monitor value has not reached the valve upper limit value until the monitor value of the valve opening degree rises from the lower limit value of the valve opening degree and returns to the lower limit value of the valve opening degree. Accordingly, the processor19adoes not count up the number-of-times of valve opening/closing.

Further, as in a period (b) inFIG. 3, the processor19adoes not count up the count value of the number-of-times of valve opening/closing for a period in which the monitor value of the valve opening degree becomes from less than the lower limit value of the valve opening degree to the upper limit value of the valve opening degree or more and then does not becomes the lower limit value of the valve opening degree or less. Therefore, since the monitor value of the valve opening degree exceeds the lower limit value of the valve opening degree until the monitor value of the valve opening degree transitions to the lower limit value of the valve opening degree, the processor19adoes not count up the count value of the number-of-times of valve opening/closing as the upper limit value is exceeded a plurality of times, and the number-of-times of valve opening/closing is counted as one time. Therefore, in the valve opening degree sequence as shown inFIG. 3, although the upper limit value of the valve opening degree is exceeded twice, since the processor19adetermines the valve opening/closing happens once, the count of the number-of-times of valve opening/closing is once.

Since the count of the number-of-times of valve opening/closing is performed with an operation between a value from 0% of the opening degree (FULL CLOSE) to the lower limit value of the valve opening degree and a value from the upper limit value of the valve opening degree to 100% of the opening degree (FULL OPEN), it is possible to count the number-of-times of opening/closing of a part (valve) that deteriorates even if “FULL CLOSE” or “FULL OPEN” is not reached. Since the lower limit value of the valve opening degree is determined such that a fluctuation value of the valve opening degree during pressure control in the film-forming recipe falls within a range below the lower limit value of the valve opening degree, the number-of-times of valve opening/closing can be counted, for example, even when the APC valve15is set to “FULL OPEN” while the pressure control is being performed in the film-forming recipe, the number of times the valve is opened and closed can be counted.

The processor19adetermines the number-of-times of valve opening/closing counted as described above by using a threshold value of an upper limit value. The number of times before reaching an endurance number-of-times of the APC valve15is set as the upper limit value for the number-of-times of valve opening/closing, and when the count value of the number-of-times of valve opening/closing reaches the upper limit value, a user is notified of a valve replacement time by an alarm report. For example, as shown inFIG. 4, the upper limit value of the number-of-times of valve opening/closing is set to 10,000 times, and an alarm is issued when the count value reaches 10,000 while executing Recipe 1. Further, for example, as the wafer discharge (Wafer D.CHG) after the film-forming recipe of Recipe 1, that is, the boat unloading step, is completed, the wafer charge (Wafer CHG) before the start of the film-forming recipe of next Recipe 2, that is, the boat loading step, is stopped for the valve replacement work, so certain process when replacing the valve (for example, valve replacement) can be executed. The upper limit value of the number-of-times of valve opening/closing is set based on a manufacturer's guaranteed value or a past example of the number-of-times of valve opening/closing until a failure.

In the present embodiment, when the monitor value of the valve opening degree becomes the lower limit value of the valve opening degree or more from less than the lower limit value of the valve opening degree, the monitoring for whether or not the valve opening/closing happens is started. However, when the monitor value of the valve opening degree becomes the upper limit value of the valve opening degree or more, the monitoring for whether or not the valve opening/closing happens may be started. In this case, when the monitor value of the valve opening degree becomes the lower limit value of the valve opening degree, it is determined that there is valve opening/closing, and the count value of the number-of-times of valve opening/closing is counted up.

If the APC valve is replaced with a new one due to a failure of the APC valve while the present disclosure is applied to perform the count of the number-of-times of valve opening/closing, the number-of-times of valve opening/closing can be set to 0 time by the processor19aor a host controller. For example, as shown inFIG. 5A, the current value, which is the monitor value of the number-of-times of valve opening/closing, is set to 0 time by a current value clear button.

Further, if the present disclosure is applied to the APC valve for which the number-of-times of valve opening/closing has already been counted without applying the present disclosure, the processor19aor the host controller (not shown) may set a certain offset value as the number-of-times of valve opening/closing. For example, as shown inFIG. 5B, the current value, which is the monitor value of the number-of-times of valve opening/closing is set to 150 times by a current value change button. This function is used when replacing the pressure controller without replacing the APC valve being used. The numerical value to be set (150in this case) is obtained, for example, by calculating the number-of-times valve opening/closing of the present disclosure from the past recipes performed.

In the present embodiment, it is described that the monitor value of the opening degree of the APC valve is monitored for a period in which the pressure is controlled during the execution of the process recipe. However, without limited to this period, the monitor value of the opening degree of the APC valve may be monitored all the time while the process recipe is being executed. Alternatively, a step of the process recipe for monitoring the monitor value of the opening degree of the APC valve may be designated in advance and the monitor value of the opening degree of the APC valve may be monitored in the designated step.

Further, the count of the number-of-times of valve opening/closing may be performed by the pressure controller19binstead of the processor19a. Further, in addition to the above-described number-of-times of valve opening/closing, criteria for replacement of the APC valve may be the valve opening/closing time, the area (a flow rate of gas flowing when opening a vertical axis, or a horizontal axis opening period) during one valve opening/closing, etc.

The substrate processing apparatus according to the present disclosure can be applied not only to a semiconductor manufacturing apparatus but also to an apparatus for processing a glass substrate such as a LCD apparatus. Further, the substrate processing apparatus according to the present disclosure does not limit the process in the furnace, and can perform film-forming processes including a CVD, a PVD, a process of forming an oxide film or a nitride film, and a process of forming a film containing metal. Further, the substrate processing apparatus according to the present disclosure can be applied to an exposure apparatus, a lithography apparatus, a coating apparatus, a CVD apparatus using plasma, and the like.

Although the present disclosure has been specifically described above based on the present embodiment, it is needless to say that the present disclosure is not limited to the above embodiment and can be modified in various forms.

According to the present disclosure in some embodiments, it is possible to know in advance the timing of replacement of a pressure control valve.