Gas management method and substrate processing system

Abstract

To provide a gas management method for managing raw material gas supplied to a substrate treatment apparatus; and to provide a substrate processing system.SOLUTION: In a gas management method in a substrate processing system, a raw material vessel for storing a raw material is heated in a heating part, and vaporized raw material gas is supplied, together with carrier gas, into a treatment vessel for storing a substrate, to thereby apply processing to the substrate. In the gas management method, the heating part is controlled based on the weight of the substrate after processing.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to gas management methods and substrate processing systems. [Background technology]

[0002] A substrate processing system is known that performs a film forming process on a substrate by heating a source container containing a solid source material in a heating unit and supplying the vaporized source gas together with a carrier gas to a substrate processing apparatus. Patent Document 1 also describes that a weight difference between the weight of the substrate before exposure and the weight of the substrate after exposure is calculated, and the thickness of a contamination film generated by the exposure process is calculated based on the weight difference. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6419581 Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a gas management method for managing a source gas supplied to a substrate processing apparatus, and a substrate processing system. [Means for solving the problem]

[0005] In order to solve the above problems, according to one aspect, a raw material container that contains raw materials is heated by a heating unit. The heated and vaporized source gas is supplied together with a carrier gas to a processing vessel containing a substrate. A gas management method for a substrate processing system that processes the substrate, comprising: When is below the threshold , Next processing the heating section Increase the set temperature of A gas management method is provided that controls [Effects of the Invention]

[0006] According to one aspect, it is possible to provide a gas management method and a substrate processing system for managing a source gas supplied to a substrate processing apparatus. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram illustrating an example of a configuration of a substrate processing system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic explanatory view illustrating the configuration of a substrate processing apparatus and a raw material supply apparatus. [Figure 3] FIG. 2 is a schematic explanatory view showing the configuration of a raw material container and its surroundings. [Figure 4] 10 is a flowchart illustrating a gas management method in the substrate processing system according to the present embodiment. [Figure 5] 10 is an example of a graph showing the relationship between the number of film formations and the wafer weight in the gas management method for the substrate processing system according to the reference example. [Figure 6] 10 is an example of a graph showing the relationship between the number of film formations and the wafer weight in the gas management method for the substrate processing system according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] FIG. 1 is a diagram illustrating an example of the configuration of a substrate processing system 1 according to this embodiment.

[0010] The substrate processing system 1 includes a substrate processing apparatus 10, a raw material supply apparatus 20, a wafer weight measuring apparatus 100, and a control unit 200.

[0011] The substrate processing apparatus 10 is a film forming apparatus that performs a film forming process on a semiconductor wafer (hereinafter simply referred to as a wafer W), which is an example of a substrate. The raw material supply apparatus 20 supplies a raw material gas used in the film forming process to the substrate processing apparatus 10 via a supply path 14.

[0012] The wafer weight measuring device 100 measures the weight of the wafer W that has been subjected to a film formation process in the substrate processing apparatus 10. The wafer weight measuring device 100 also measures the weight of the wafer W before the film formation process in the substrate processing apparatus 10.

[0013] The control unit 200 controls the substrate processing apparatus 10 , the raw material supply apparatus 20 , and the wafer weight measuring apparatus 100 .

[0014] The wafer weight measuring device 100 may be configured to be provided outside the substrate processing system 1. In this configuration, the measurement data of the wafer weight measuring device 100 may be input to the control unit 200 directly or via a signal line.

[0015] FIG. 2 is a schematic explanatory view illustrating the configuration of the substrate processing apparatus 10 and the raw material supply apparatus 20. As shown in FIG.

[0016] The substrate processing apparatus 10 is a semiconductor manufacturing apparatus such as a film formation apparatus. The substrate processing apparatus 10 includes a processing chamber 11 and a main control unit 15. When the substrate processing apparatus 10 is, for example, a film formation apparatus, the substrate processing apparatus 10 performs a film formation process on a wafer W accommodated in the processing chamber 11.

[0017] The processing vessel 11 is made of an aluminum alloy or the like and has a cylindrical shape. An opening is formed in the sidewall of the processing vessel 11 for loading and unloading the wafer W into and out of the processing vessel 11, and a gate valve is provided at the opening for opening and closing the opening (both not shown). A mounting table 12 for mounting the wafer W thereon is provided inside the processing vessel 11. The mounting table 12 has a chuck device for fixing the wafer W and a temperature adjustment unit for adjusting the temperature of the wafer W (both not shown).

[0018] An exhaust path 13 that exhausts gas from the processing vessel 11 is connected to the processing vessel 11. A pressure adjustment valve, a vacuum pump, and the like are provided on the exhaust path 13 (both not shown). Furthermore, one end of a supply path 14 that supplies gas is connected to the processing vessel 11. The other end of the supply path 14 is connected to a raw material supply device 20. That is, the processing vessel 11 and the raw material supply device 20 of the substrate processing apparatus 10 are in communication with each other via the supply path 14.

[0019] The raw material supply apparatus 20 has raw material containers 21. The raw material supply apparatus 20 also has a heating unit 30 that heats the raw material containers 21, a carrier gas supply mechanism 40 that supplies a carrier gas to each raw material container 21, and a supply control unit 90 that controls each component of the raw material supply apparatus 20. The supply path 14, each raw material container 21, and the carrier gas supply mechanism 40 are interconnected by multiple gas paths 50. Furthermore, the raw material supply apparatus 20 has multiple on-off valves 60 in the gas paths 50 around the raw material containers 21.

[0020] FIG. 3 is a schematic diagram illustrating the configuration of the source container 21 and its surroundings. As shown in FIGS. 2 and 3, the source container 21 may be a tank that contains multiple source materials M and can vaporize (sublimate) the source materials M by heating using a heating unit 30. The source material M in the source container 21 is a solid source material or a liquid source material. The source material M in the source container 21 is not particularly limited, but examples include chloride compounds such as aluminum chloride (AlCl) and copper chloride (AlCu). Alternatively, the source material M may be metal organics such as Si, Hf, Ta, Zr, Al, Ti, Zn, In, Ga, or P, or other solid or liquid source materials. In this embodiment, a case where aluminum chloride is used as the solid source material M will be described. Note that the term "vaporization" in this embodiment encompasses both the concept of a source material sublimating into a gas and the concept of a liquid source evaporating into a gas.

[0021] Although FIG. 1 shows an example in which one raw material container 21 is provided, the raw material supply device 20 may be configured to include two or more raw material containers 21.

[0022] 3, the raw material container 21 is formed in a cylindrical or rectangular tubular shape extending in the vertical direction. A plurality of trays 22 are provided in the raw material container 21 at approximately equal intervals in the vertical direction. One or more raw materials M are placed on each tray 22.

[0023] The source material container 21 is made of a material with high thermal conductivity (such as alumina). A heating unit 30 for heating the source material container 21 is provided outside the source material container 21 or on the peripheral wall of the container. The heating unit 30 heats the source material M in the source material container 21 under the control of a supply control unit 90. For example, an electric heater such as a sheath heater or a hand heater can be used as the heating unit 30.

[0024] The carrier gas supply mechanism 40 supplies a carrier gas to the gas paths 50 connected to the source material container 21. Examples of the carrier gas include inert gases such as argon gas (Ar gas), helium gas (He gas), and nitrogen gas (N gas). For example, the carrier gas supply mechanism 40 includes a carrier gas supply source, a regulator that reduces the pressure of the carrier gas delivered from the supply source, and a valve that opens or closes the flow path of each gas path 50 (all not shown).

[0025] The gas path 50 includes an upstream path 51 connecting the carrier gas supply mechanism 40 and the raw material container 21, a downstream path 52 connecting the raw material container 21 and the supply path 14, and a bypass path 53 that bypasses the raw material container 21. That is, the raw material supply device 20 forms a primary side through which the upstream path 51 causes the carrier gas to flow into the raw material container 21, and a secondary side through which the downstream path 52 causes the vaporized raw material gas to flow out together with the carrier gas. The bypass path 53 connects the upstream path 51 and the downstream path 52.

[0026] The on-off valves 60 around the raw material container 21 include an upstream valve 61 provided in the upstream path 51, a downstream valve 62 provided in the downstream path 52, and a bypass valve 63 provided in the bypass path 53. The upstream valve 61 is provided downstream of the connection point of the upstream path 51 with the bypass path 53. The downstream valve 62 is provided upstream of the connection point of the downstream path 52 with the bypass path 53.

[0027] Each on-off valve 60 is connected to a supply control unit 90, and opens (fully opens) or closes (fully closes) the flow path of each route based on the control of the supply control unit 90. Each on-off valve 60 allows gas to flow through the flow path in the open state, and blocks the flow of gas in the flow path in the closed state.

[0028] In addition to the upstream valve 61, the upstream path 51 also has a mass flow controller 54 and an upstream pressure gauge 71. The upstream path 51 may also include a safety valve, a constant pressure valve, a filter, a heater, and the like.

[0029] The mass flow controller 54 is provided on the upstream path 51 upstream of the connection point of the bypass path 53 (on the carrier gas supply mechanism 40 side), and is connected to the supply control unit 90. The mass flow controller 54 adjusts the flow rate of the carrier gas supplied from the carrier gas supply mechanism 40 to the raw material container 21 based on the control of the supply control unit 90.

[0030] The upstream pressure gauge 71 is provided between the mass flow controller 54 and the upstream valve 61 (and the connection point of the bypass path 53). The upstream pressure gauge 71 detects the internal pressure (pressure of the carrier gas) of the flow path of the piping that constitutes the upstream path 51, and transmits information on the detected pressure value to the supply control unit 90. The upstream pressure gauge 71 can be any of various detectors that can detect total pressure (static pressure, dynamic pressure). The upstream pressure gauge 71 may be provided in the upstream path 51 upstream of the mass flow controller 54.

[0031] In addition to the downstream valve 62, the downstream path 52 has a downstream pressure gauge 72. The downstream pressure gauge 72 is provided downstream of the downstream valve 62 (and the connection point of the bypass path 53). The downstream pressure gauge 72 detects the internal pressure (pressure of the carrier gas and the source gas) of the flow path of the piping that constitutes the downstream path 52, and transmits information on the detected pressure value to the supply control unit 90.

[0032] Returning to FIG. 2 , the gas path 50 of the raw material supply device 20 further includes a first branch path 55 branching off from the upstream path 51. The other end of the first branch path 55 is connected to the downstream path 52 between the downstream valve 62 and the downstream pressure gauge 72. A mass flow controller 56 is provided midway along the first branch path 55. The mass flow controller 56 adjusts the flow rate of the carrier gas flowing from the upstream path 51 to the downstream path 52 via the first branch path 55.

[0033] In the substrate processing system 1 having the above-described substrate processing apparatus 10 and raw material supply apparatus 20, the operation of the entire system is controlled by a main control unit 15 of the substrate processing apparatus 10. A supply control unit 90 of the raw material supply apparatus 20 is connected to the main control unit 15 via an appropriate communication means 16 and operates based on commands from the main control unit 15 to control the operation of the raw material supply apparatus 20. The communication means 16 may employ either wired or wireless communication, and may be configured to directly connect the control units to each other or may be configured to use a network such as a local area network (LAN). Note that the substrate processing system 1 may be configured such that the main control unit 15 has the function of the supply control unit 90, but does not include the supply control unit 90.

[0034] The main control unit 15 has a controller main body 17 that controls the entire substrate processing system 1, and a user interface 18 that is connected to the controller main body 17. The controller main body 17 and the supply control unit 90 are configured by a computer, a control circuit board, etc.

[0035] For example, the controller main body 17 has a processor, a memory, an input / output interface, and an electronic circuit (all not shown). The processor executes a program recorded in the memory, whereby the controller main body 17 transmits and receives various signals to and from each component of the substrate processing system 1, thereby carrying out substrate processing.

[0036] The user interface 18 may be, for example, a keyboard through which a user inputs commands, or a display that visualizes and displays the operating status of the substrate processing system 1. Alternatively, the user interface 18 may be a device such as a touch panel, a mouse, a microphone, or a speaker.

[0037] The supply control unit 90 also has one or more processors 91, a memory 92, an input / output interface (not shown), and electronic circuits. The processor 91 is one or a combination of a CPU, an ASIC, an FPGA, and a circuit made up of multiple discrete semiconductors. The memory 92 includes volatile memory and non-volatile memory (e.g., a compact disc, a DVD, a hard disk, a flash memory, etc.), and stores a program for operating the raw material supply device 20 and recipes such as process conditions.

[0038] Based on instructions from the main control unit 15, the supply control unit 90 sends and receives various signals to and from each component of the raw material supply device 20 by having the processor 91 execute programs and recipes stored in the memory 92, thereby supplying gas to the substrate processing apparatus 10.

[0039] The main control unit 15 of the substrate processing apparatus 10 transmits a supply command to the supply control unit 90 to supply the source gas to the processing chamber 11 at an appropriate timing when processing the wafer W (for example, after the wafer W has been placed on the mounting table 12 and the processing chamber 11 has been depressurized). Upon receiving this supply command, the supply control unit 90 controls each component of the source gas supply device 20 to start supplying the source gas.

[0040] When the supply of the raw material gas starts (or after the raw material supply device 20 is started), the supply control unit 90 operates the heating unit 30 to heat the raw material container 21. As a result, the temperature of the raw material M in the raw material container 21 rises to a temperature at which it can be vaporized. In addition, the supply control unit 90 opens the upstream valve 61 and the downstream valve 62, and controls the mass flow controllers 54 and 56 to supply a mixed gas of the carrier gas and the raw material gas to the processing container 11. As a result, a film formation process is performed on the wafer W.

[0041] Next, a gas management method for the substrate processing system 1 according to this embodiment will be described with reference to Fig. 4. Fig. 4 is a flowchart illustrating the gas management method for the substrate processing system 1 according to this embodiment.

[0042] In step S101, the control unit 200 sets the set temperature (heating temperature) of the heating unit 30 to a predetermined set temperature.

[0043] In step S102, the control unit 200 performs a film formation process on the wafer W. Specifically, the wafer W before the film formation process is transported to the substrate processing apparatus 10 and placed on the mounting table 12. The control unit 200 controls the heating unit 30 to a predetermined set temperature, and controls the upstream valve 61, the downstream valve 62, the mass flow controller 54, and the mass flow controller 56 to supply a mixed gas of a carrier gas and a raw material gas from the raw material supply unit 20 into the processing chamber 11. In this way, the wafer W is subjected to the film formation process.

[0044] In step S103, the control unit 200 measures the weight of the wafer W that has been subjected to the film formation process in step S102. Specifically, the wafer W that has been subjected to the film formation process is unloaded from the substrate processing apparatus 10 and transferred to the wafer weight measuring apparatus 100. Then, the weight of the wafer W is measured by the wafer weight measuring apparatus 100.

[0045] In step S104, the control unit 200 determines whether the weight of the wafer W that has been subjected to the film formation process in step S102 is within the range of the reference value. If the weight of the wafer W is within the range of the reference value (S104 YES), the process of the control unit 200 returns to step S102 and performs the film formation process on the next wafer W. If the weight of the wafer W is not within the range of the reference value (S104 NO), the process of the control unit 200 proceeds to S105.

[0046] In step S105, the control unit 200 resets and increases the set temperature (heating temperature) of the heating unit 30. By increasing the set temperature, the amount of vaporization of the solid raw material M in the raw material container 21 increases.

[0047] In step S106, the control unit 200 performs a film formation process on the wafer W. Specifically, the wafer W before the film formation process is transported to the substrate processing apparatus 10 and placed on the mounting table 12. The control unit 200 controls the heating unit 30 to a predetermined set temperature, and controls the upstream valve 61, the downstream valve 62, the mass flow controller 54, and the mass flow controller 56 to supply a mixed gas of a carrier gas and a raw material gas from the raw material supply unit 20 into the processing chamber 11. In this way, the wafer W is subjected to a film formation process.

[0048] In step S107, the control unit 200 measures the weight of the wafer W that has been subjected to the film formation process in step S106. Specifically, the wafer W that has been subjected to the film formation process is unloaded from the substrate processing apparatus 10 and transferred to the wafer weight measuring apparatus 100. Then, the weight of the wafer W is measured by the wafer weight measuring apparatus 100.

[0049] In step S108, the control unit 200 determines whether the weight of the wafer W that has been subjected to the film formation process in step S106 is within the range of the reference value. If the weight of the wafer W is within the range of the reference value (S108 YES), the process by the control unit 200 returns to step S102, and the film formation process is performed on the next wafer W. If the weight of the wafer W is not within the range of the reference value (S108 NO), the process by the control unit 200 proceeds to S109.

[0050] In step S109, the control unit 200 determines that the raw material container 21 should be replaced, and instructs the operator to replace the raw material container 21.

[0051] In the description of steps S104 and S108, it is determined whether the weight of the wafer W after the film formation process is within a reference value range, but this is not limited to this. For example, before the film formation process (steps S102 and S106), the weight of the wafer W before the film formation process may be measured in advance by the wafer weight measuring device 100. Then, in steps S104 and S108, the control unit 200 may be configured to determine whether the weight difference between the weight of the wafer W before the film formation process and the weight of the wafer W after the film formation process is within a reference value range.

[0052] Next, a gas management method for the substrate processing system 1 according to this embodiment and a gas management method for the substrate processing system 1 according to a reference example will be described in comparison.

[0053] 5 is an example of a graph showing the relationship between the number of film formations (the number of wafers W subjected to film formation processing) and wafer weight in the gas management method of the substrate processing system 1 according to the reference example. The horizontal axis represents the number of film formations, and the vertical axis represents the wafer weight. In the gas management method of the substrate processing system 1 according to the reference example, the set temperature of the heating unit 30 is set constant at temperature T1.

[0054] As the number of film formation processes increases and the source material M in the source material container 21 is consumed, the amount of vaporized source material M decreases, and the supply amount of source gas decreases. As a result, the thickness of the film formed on the wafer W decreases, and the weight of the wafer W after the film formation process changes. In addition, a decrease in the supply amount of source gas causes coverage defects. For this reason, coverage defects can be estimated from the weight of the wafer W after the film formation process. In FIG. 5, the threshold (product defect threshold) at which coverage defects occur on the wafer W after the film formation process is indicated by a dashed line.

[0055] Furthermore, the substrate processing system 1 generates a source gas by heating the solid source material M in the source material container 21, and supplies a carrier gas to the source material container 21, thereby supplying a mixed gas of the source gas and the carrier gas to the processing container 11. For this reason, it is difficult for the substrate processing system 1 to control the flow rate of the source gas supplied from the source material container 21. That is, it is difficult to calculate the consumption amount of the source gas.

[0056] Therefore, in the gas management method of the substrate processing system 1 according to the reference example, in order to prevent coverage failure (product failure) due to a shortage of source gas, the source container 21 is replaced when a certain period of time (a predetermined number of film formations) has passed since the start of use of the source container 21, thereby preventing coverage failure (product failure). However, in the gas management method of the substrate processing system 1 according to the reference example, the source container 21 is replaced even though the source material M remains in the source container 21, which increases costs.

[0057] 6 is an example of a graph showing the relationship between the number of film formations (the number of wafers W subjected to film formation processing) and wafer weight in the gas management method of the substrate processing system 1 according to this embodiment. The horizontal axis represents the number of film formations, and the vertical axis represents the wafer weight. In FIG. 6, the graph showing the relationship between the number of film formations and wafer weight in the gas management method according to the reference example is indicated by a dotted line.

[0058] As the number of film formation operations increases and the source material M in the source material container 21 is consumed, the amount of vaporized source material M decreases, and the supply rate of source gas decreases. As a result, the thickness of the film formed on the wafer W decreases, and the weight of the wafer W after the film formation process changes. When the weight of the wafer W falls below a predetermined threshold (the temperature control threshold indicated by the dashed-dotted line in FIG. 6), the control unit 200 increases the set temperature (heating temperature) of the heating unit 30 from temperature T1 to temperature T2 (T2>T1) (see S105). This increases the amount of vaporized source material M, preventing a decrease in the supply rate of source gas. Furthermore, the film formation process can be continued while preventing product defects due to poor coverage.

[0059] When the number of film formations increases further and the weight of the wafer W at the set temperature T2 becomes equal to or less than a predetermined threshold (temperature control threshold), the control unit 200 raises the set temperature of the heating unit 30 from temperature T2 to temperature T3 (T3>T2) (see S105). This increases the amount of vaporization of the raw material M, and prevents a decrease in the supply rate of the raw material gas. Furthermore, the film formation process can be continued while preventing product defects due to poor coverage.

[0060] Similarly, when the number of film formations increases and the weight of the wafer W at the set temperature T3 becomes equal to or less than a predetermined threshold (temperature control threshold), the control unit 200 raises the set temperature of the heating unit 30 from temperature T3 to temperature T4 (T4>T3). This increases the amount of vaporization of the raw material M, preventing a decrease in the supply rate of the raw material gas. Furthermore, the film formation process can be continued while preventing product defects due to poor coverage.

[0061] Furthermore, if the weight of the wafer W does not reach the threshold value (temperature control threshold value) even when the set temperature (heating temperature) of the heating unit 30 is increased (see S108·NO), it is determined that the source material container 21 should be replaced (S109). Note that it may also be determined that the source material container 21 should be replaced when the set temperature reaches a predetermined temperature.

[0062] As described above, the gas management method of the substrate processing system 1 according to this embodiment can prevent product defects (poor coverage) due to a shortage of source gas. Furthermore, the source material M in the source material container 21 can be used efficiently, reducing the cost of the source material gas. Furthermore, the number of steps required for replacing the source material container 21 can be reduced.

[0063] The control unit 200 may continuously accumulate correlation data between the weight of the wafer W and the measurement values of the upstream pressure gauge 71 and the downstream pressure gauge 72. The control unit 200 may then estimate the weight of the wafer W after the film formation process based on the measurement values of the upstream pressure gauge 71 and the downstream pressure gauge 72 and the correlation data. The control unit 200 may also control the set temperature (heating temperature) of the heating unit 30 based on the estimated weight of the wafer W after the film formation process. The control unit 200 may also determine the timing of replacing the source material container 21 based on the estimated weight of the wafer W after the film formation process. Thereby, after the correlation data is created, it is possible to omit the weight measurement of the wafer W after the film formation process by the wafer weight measuring device 100.

[0064] The embodiments of the present disclosure should be considered in all respects as illustrative and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0065] 1. Substrate Processing System 10. Substrate processing equipment 11 Processing container 14 Supply Channels 20 Raw material supply device 21 Raw material container 22 Tray 30 Heating section 40 Carrier gas supply mechanism 50 Gas Route 60 Opening and closing valve 71 Upstream pressure gauge 72 Downstream pressure gauge 90 Supply control section 100 Wafer weight measuring device 200 control section W wafer M Raw material

Claims

1. A gas management method for a substrate processing system that processes a substrate by heating a source container that contains a source material with a heating unit and supplying a vaporized source gas together with a carrier gas to a processing container that contains a substrate, comprising: When the weight of the substrate after processing becomes equal to or less than a threshold value, the set temperature of the heating unit for the next processing is controlled to be increased. Gas management methods.

2. When the weight of the substrate after controlling the set temperature of the heating unit to be higher is equal to or less than a threshold value, it is determined that the source material container should be replaced. The gas management method according to claim 1 .

3. The raw material contained in the raw material container is a solid raw material or a liquid raw material. The gas management method according to claim 1 or 2.

4. a substrate processing apparatus having a processing vessel for accommodating a substrate; a raw material supply device including a raw material container for accommodating a raw material and a heating unit for heating the raw material container, and configured to supply a vaporized raw material gas together with a carrier gas to the processing vessel; a measuring device that measures the weight of the substrate; a control unit, The control unit When the weight of the substrate after processing becomes equal to or less than a threshold value, the set temperature of the heating unit for the next processing is controlled to be increased. Substrate processing system.

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