Substate processing method and substrate processing apparatus

Abstract

[assignment] A substrate processing method and a substrate processing apparatus are provided that can mitigate problems caused by the breakage of O-rings connecting chambers. [Solution] A processing chamber (6) for performing heat treatment on a semiconductor wafer (W) and a return chamber (170) for accommodating a return robot (150) are connected via a gate valve (185) and an O-ring (186). If the O-ring (186) is damaged while the processing chamber (6) is under reduced pressure during heat treatment on the semiconductor wafer (W), there is a risk that the atmosphere inside the return chamber (170) will be sucked into the processing chamber (6), causing the pressure inside the return chamber (170) to rapidly decrease. While heat treatment on the semiconductor wafer (W) is being performed in the processing chamber (6), the pressure of the gas inside the return chamber (170) is monitored, and when the pressure inside the return chamber (170) falls below a predetermined threshold value, the heat treatment is stopped, and the pressure of the processing chamber (6) and the return chamber (170) is restored to atmospheric pressure.

Description

Technology Field

[0001] The present invention relates to a substrate processing method and a substrate processing apparatus for heating a substrate by irradiating the substrate with light. The substrates to be processed include, for example, semiconductor wafers, substrates for liquid crystal display devices, substrates for flat panel displays (FPDs), substrates for optical discs, substrates for magnetic discs, or substrates for solar cells. Background Technology

[0002] In the manufacturing process of semiconductor devices, Flash Lamp Annealing (FLA), which heats semiconductor wafers in a very short time, is attracting attention. Flash Lamp Annealing is a heat treatment technology that raises the temperature of only the surface of a semiconductor wafer in a very short time (less than a few milliseconds) by irradiating the surface of the wafer with flash light using a xenon flash lamp (hereinafter, when simply referred to as "flash lamp," it means a xenon flash lamp).

[0003] The radiation spectral distribution of a xenon flash lamp extends from the ultraviolet to the near-infrared range; it has a shorter wavelength than conventional halogen lamps and closely matches the fundamental absorption band of silicon semiconductor wafers. Therefore, when flash light is irradiated onto a semiconductor wafer from a xenon flash lamp, the transmitted light is minimal, making it possible to rapidly raise the temperature of the semiconductor wafer. Furthermore, it has been found that if flash light is irradiated for a very short duration of less than a few milliseconds, only the area near the surface of the semiconductor wafer can be selectively heated.

[0004] This flash lamp annealing is used in processes requiring extremely short heating times, for example, typically for the activation of impurities implanted in semiconductor wafers. By irradiating the surface of a semiconductor wafer, into which impurities have been implanted by ion implantation, with flash light from a flash lamp, the surface of the wafer can be heated to the activation temperature in a very short time, thereby enabling only the activation of impurities without causing deep diffusion of the impurities.

[0005] Flash lamp annealing, such as for impurity activation, is performed in an atmospheric pressure atmosphere. However, depending on the content of the process, flash lamp annealing may be performed while supplying a specific processing gas (e.g., ammonia, ozone, etc.) in a reduced pressure atmosphere in which the pressure inside the processing chamber is reduced to, for example, 5 kPa to 50 kPa. Patent Document 1 discloses a technique for performing post-deposition annealing (PDA) of a high dielectric constant film by irradiating a semiconductor wafer with flash light in an ammonia atmosphere in which the pressure inside the processing chamber is reduced to 5 kPa.

[0006] In addition, Patent Document 1 discloses a transfer chamber that accommodates a transfer robot and a processing chamber that performs flash light irradiation, and a transfer robot that transfers semiconductor wafers into and out of the processing chamber. The transfer opening connecting the transfer chamber and the processing chamber is opened and closed by a gate valve. When the gate valve closes the transfer opening, the airtightness inside the processing chamber is maintained by an O-ring, thereby preventing leakage of ammonia, etc. Prior art literature

[0007] Japanese Patent Publication No. 2020-123602 The problem to be solved

[0008] The inside of the return chamber is normally maintained at atmospheric pressure. However, if the O-ring of the gate valve breaks while the processing chamber is under reduced pressure, the inside of the return chamber also rapidly depressurizes, causing problems such as damage to the quartz window installed in the return chamber.

[0009] In addition, when the above-mentioned problem occurs, it is necessary to stop the process, retrieve the semiconductor wafer being processed, and then perform maintenance work. In order to retrieve the semiconductor wafer from the processing chamber, the gate valve must be opened, but at that time, there is a risk that dangerous gases such as ammonia may be released from the processing chamber.

[0010] The present invention has been made in consideration of the above problem and aims to provide a substrate processing method and a substrate processing apparatus capable of mitigating problems caused by the breakage of O-rings connecting chambers. means of solving the problem

[0011] To solve the above problem, a first aspect of the present invention comprises a substrate processing method for heating a substrate by irradiating light onto the substrate, the method comprising: a receiving process for introducing a substrate into a processing chamber connected to a receiving chamber containing a receiving robot through a gate valve and an O-ring; a processing process for performing a heat treatment by irradiating light onto the substrate while forming an atmosphere of a predetermined reactive gas within the processing chamber containing the substrate and reducing the pressure within the processing chamber to less than atmospheric pressure; a detection process for detecting whether the pressure within the receiving chamber has become below a first threshold value of less than atmospheric pressure during the execution of the processing process; and a pressure recovery process for stopping an exhaust pump that reduces the pressure within the processing chamber and supplying an inert gas into the processing chamber to restore the pressure within the processing chamber to atmospheric pressure when it is detected that the pressure within the receiving chamber has become below the first threshold value.

[0012] In addition, in the second embodiment, in the substrate processing method according to the first embodiment, when it is detected that the pressure inside the return chamber has become below the first threshold value, an inert gas is additionally supplied into the return chamber to restore the pressure inside the return chamber to atmospheric pressure.

[0013] In addition, the third embodiment is a substrate processing method according to the first or second embodiment, wherein when it is detected in the detection process that the pressure inside the return chamber has become lower than or equal to a second threshold value which is higher than the first threshold value, the subsequent introduction of a substrate into the processing chamber is stopped while continuing the processing process, and when it is detected in the detection process that the pressure inside the return chamber has become lower than or equal to the first threshold value, the pressure recovery process is executed.

[0014] In addition, the fourth embodiment further comprises, in a substrate processing method according to any one of the first to third embodiments, a first concentration measuring process for measuring the concentration of the reactive gas remaining in the processing chamber after the processing chamber is pressured to atmospheric pressure in the pressure process, and permitting the opening of the gate valve if the concentration of the reactive gas in the processing chamber is less than or equal to a predetermined value.

[0015] In addition, the fifth embodiment, in the substrate processing method according to the fourth embodiment, prohibits the opening of the gate valve if the first concentration measurement process is not performed after the inside of the processing chamber is pressurized to atmospheric pressure in the pressure process.

[0016] In addition, the sixth embodiment further comprises, in the substrate processing method according to the fourth or fifth embodiment, a second concentration measuring process for measuring the concentration of the reactive gas in the return chamber after the processing chamber is pressurized to atmospheric pressure in the pressurization process.

[0017] Furthermore, a seventh embodiment is a substrate processing apparatus for heating a substrate by irradiating light onto the substrate, comprising: a return chamber for accommodating a return robot; a processing chamber connected to the return chamber through a gate valve and an O-ring; a first gas supply unit for supplying a predetermined reactive gas or inert gas to the processing chamber; an exhaust unit including an exhaust pump for exhausting gas from the processing chamber to reduce the pressure inside the processing chamber; a light irradiation unit for irradiating light onto a substrate accommodating the processing chamber; a first pressure gauge for measuring pressure inside the processing chamber; a second pressure gauge for measuring pressure inside the return chamber; and a control unit for controlling the first gas supply unit and the exhaust unit. During the execution of a heat treatment in which light is irradiated onto the substrate while forming an atmosphere of the reactive gas inside the processing chamber and reducing the pressure inside the processing chamber accommodating the substrate to less than atmospheric pressure, when it is detected that the pressure inside the return chamber measured by the second pressure gauge has become less than a first threshold value below atmospheric pressure, the control unit stops the exhaust pump and, inside the processing chamber The first gas supply unit is controlled to supply an inert gas to pressurize the inside of the processing chamber to atmospheric pressure.

[0018] In addition, the eighth embodiment further comprises a second gas supply unit that supplies an inert gas to the return chamber in the substrate processing apparatus according to the seventh embodiment, and when it is detected that the pressure inside the return chamber has become below the first threshold value, the control unit controls the second gas supply unit to supply an inert gas to the return chamber so as to restore the pressure inside the return chamber to atmospheric pressure.

[0019] In addition, the ninth embodiment is a substrate processing apparatus according to the seventh or eighth embodiment, wherein when it is detected that the pressure inside the return chamber measured by the second pressure gauge has become lower than or equal to a second threshold value that is higher than the first threshold value, the subsequent introduction of a substrate into the processing chamber is stopped while the heating treatment is continued.

[0020] In addition, the 10th embodiment further comprises a first gas detection unit for measuring the concentration of the reactive gas in the processing chamber in a substrate processing apparatus according to any one of the 7th to 9th embodiments, and permits the opening of the gate valve if the concentration of the reactive gas remaining in the processing chamber is less than or equal to a predetermined value after the processing chamber is pressurized to atmospheric pressure.

[0021] In addition, the 11th embodiment, in a substrate processing apparatus according to the 10th embodiment, prohibits the opening of the gate valve if the concentration of the reactive gas in the processing chamber is not measured by the first gas detection unit after the processing chamber is pressurized to atmospheric pressure.

[0022] Additionally, the 12th embodiment further comprises a second gas detection unit for measuring the concentration of the reactive gas in the return chamber in a substrate processing apparatus according to the 10th or 11th embodiment, and after the processing chamber is pressurized to atmospheric pressure, the concentration of the reactive gas in the return chamber is measured by the second gas detection unit. Effects of the invention

[0023] According to the substrate processing method of the first to sixth embodiments, when it is detected that the pressure inside the return chamber has fallen below a first threshold value during the execution of the processing process, the exhaust pump that reduces the pressure inside the processing chamber is stopped, and an inert gas is supplied to the processing chamber to restore the pressure inside the processing chamber to atmospheric pressure. Therefore, the pressure difference between the processing chamber and the return chamber is reduced, thereby preventing the pressure inside the return chamber from rapidly decreasing and mitigating problems caused by the breakage of the O-ring connecting the chambers.

[0024] In particular, according to the substrate processing method of the second embodiment, when it is detected that the pressure inside the return chamber has fallen below a first threshold value, an inert gas is additionally supplied into the return chamber to restore the pressure inside the return chamber to atmospheric pressure, thereby making the pressure difference between the processing chamber and the return chamber smaller.

[0025] In particular, according to the substrate processing method of the fourth embodiment, after the processing chamber is pressurized to atmospheric pressure during the pressure process, the opening of the gate valve is permitted when the concentration of the reactive gas in the processing chamber is below a predetermined value, thereby preventing the leakage of the reactive gas from the processing chamber to the return chamber.

[0026] According to the substrate processing apparatus of the 7th to 12th embodiments, when it is detected that the pressure inside the return chamber has fallen below a first threshold value of less than atmospheric pressure during the execution of the heat treatment, the exhaust pump is stopped and an inert gas is supplied into the processing chamber to restore the pressure inside the processing chamber to atmospheric pressure. Therefore, the pressure difference between the processing chamber and the return chamber is reduced, thereby preventing the pressure inside the return chamber from rapidly decreasing and mitigating problems caused by the breakage of the O-ring connecting the chambers.

[0027] In particular, according to the substrate processing apparatus of the eighth embodiment, when it is detected that the pressure inside the return chamber has fallen below a first threshold value, an inert gas is supplied into the return chamber to restore the pressure inside the return chamber to atmospheric pressure, thereby making the pressure difference between the processing chamber and the return chamber smaller.

[0028] In particular, according to the substrate processing apparatus of the 10th embodiment, when the concentration of reactive gas remaining in the processing chamber is lower than a predetermined value after the processing chamber is pressurized to atmospheric pressure, the opening of the gate valve is permitted, thereby preventing the leakage of reactive gas from the processing chamber to the return chamber. Brief explanation of the drawing

[0029] FIG. 1 is a plan view showing a substrate processing apparatus according to the present invention. Figure 2 is a front view of the substrate processing device of Figure 1. Figure 3 is a cross-sectional view showing the configuration of the heat treatment section. Figure 4 is a perspective view showing the overall appearance of the retaining part. Figure 5 is a plan view of the susceptor. Figure 6 is a cross-sectional view of a susceptor. Figure 7 is a plan view of the material handling mechanism. Fig. 8 is a side view of the material handling mechanism. FIG. 9 is a plan view showing the arrangement of multiple halogen lamps. FIG. 10 is a schematic diagram showing the supply and exhaust mechanism for the processing chamber and the return chamber. FIG. 11 is a block diagram showing the configuration of the control unit. FIG. 12 is a flowchart showing the procedure for pressure control in the case where the O-ring is damaged. Figure 13 is a flowchart showing the procedure for checking residual gas in the processing chamber. Figure 14 is a diagram showing an example of a GUI displayed on a display unit when performing a residual gas check. Figure 15 is a diagram showing an example of a GUI displayed on a display unit during concentration measurement. FIG. 16 is a drawing showing an example of a GUI displayed on a display unit when the opening of a gate valve is permitted. Specific details for implementing the invention

[0030] Embodiments of the present invention will be described in detail below with reference to the drawings. In the following, expressions indicating relative or absolute positional relationships (e.g., “in one direction,” “along one direction,” “parallel,” “orthogonal,” “center,” “concentric,” “coaxial,” etc.) shall, unless specifically stated otherwise, not only strictly indicate such positional relationships but also indicate states of relative displacement with respect to angle or distance within a range where tolerances or equivalent functions can be obtained. Furthermore, expressions indicating the same state (e.g., “identical,” “equal,” “homogeneous,” etc.) shall, unless specifically stated otherwise, not only indicate states of being quantitatively and strictly identical but also indicate states where tolerances or differences exist within a range where equivalent functions can be obtained. In addition, expressions indicating a shape (e.g., “circular shape,” “rectangular shape,” “cylindrical shape,” etc.) shall, unless specifically stated otherwise, not only indicate the shape strictly in geometric terms but also indicate a shape within a range where the same degree of effect is obtained, and may, for example, have irregularities or chamfers. In addition, expressions such as “prepare,” “equip,” “provide,” “include,” and “have” a component are not exclusive expressions that exclude the existence of other components. In addition, the expression “at least one of A, B, and C” includes “A only,” “B only,” “C only,” “any two of A, B, and C,” and “all of A, B, and C.”

[0031] First, an example of the configuration of a substrate processing apparatus according to the present invention will be described. FIG. 1 is a plan view showing a substrate processing apparatus (100) according to the present invention, and FIG. 2 is a front view thereof. The substrate processing apparatus (100) is a flash lamp annealing apparatus that heats a semiconductor wafer (W) in the shape of a disc by irradiating it with flash light as a substrate. The size of the semiconductor wafer (W) to be processed is not particularly limited, but for example, it is φ300mm or φ450mm. In addition, in FIG. 1 and subsequent drawings, the dimensions or number of each part are exaggerated or simplified as necessary for ease of understanding. Also, in FIG. 1 to FIG. 3, an XYZ orthogonal coordinate system is assigned in which the Z-axis direction is the vertical direction and the XY plane is the horizontal plane to clarify their directional relationship.

[0032] As shown in FIGS. 1 and 2, the substrate processing device (100) comprises an indexer unit (101) for bringing an unprocessed semiconductor wafer (W) into the device from the outside and taking out a processed semiconductor wafer (W) from the device, an alignment unit (230) for determining the position of an unprocessed semiconductor wafer (W), a first cooling unit (130) and a second cooling unit (140) for cooling the semiconductor wafer (W) after heat treatment, a heat treatment unit (160) for performing flash heat treatment on the semiconductor wafer (W), and a transport robot (150) for receiving the semiconductor wafer (W) to the first cooling unit (130), the second cooling unit (140), and the heat treatment unit (160). Additionally, the substrate processing device (100) is equipped with a control unit (3) that controls the operating mechanism and the transport robot (150) installed in each of the above processing units to proceed with the flash heating process of the semiconductor wafer (W).

[0033] The indexer section (101) is equipped with a load port (110) for arranging and placing multiple carriers (C), and a water robot (120) for taking out unprocessed semiconductor wafers (W) from each carrier (C) and receiving processed semiconductor wafers (W) in each carrier (C). More precisely, the indexer section (101) has three load ports installed, and the load port (110) is a general term including a first load port (110a), a second load port (110b), and a third load port (110c) (if the three load ports are not specifically distinguished, they are simply referred to as load ports (110). Among the three load ports, the first load port (110a) and the second load port (110b) have carriers (C) containing semiconductor wafers (W) (product wafers) that become products placed thereon. Meanwhile, the third load port (110c) is a load port dedicated to a dummy carrier (DC) that accommodates a dummy wafer (DW). That is, only a dummy carrier (DC) is loaded into the third load port (110c). Additionally, the dummy wafer (DW) is a wafer that has the same shape and material as the product wafer but is not processed as a product.

[0034] A carrier (C) and a dummy carrier (DC) containing an unprocessed semiconductor wafer (W) are transported by an unmanned transport vehicle (AGV, OHT), etc., and placed in a load port (110). Tags for identification are installed on the carrier (C) and the dummy carrier (DC), and the tags of the carrier (C) and the dummy carrier (DC) placed in the load port (110) are read by a tag reader (not shown). In addition, a carrier (C) and a dummy carrier (DC) containing a processed semiconductor wafer (W) are also taken from the load port (110) by an unmanned transport vehicle.

[0035] In addition, in the load port (110), the carrier (C) and the dummy carrier (DC) are configured to be vertically movable as indicated by the arrow (CU) in FIG. 2 so that the water supply robot (120) can perform the loading and unloading of any semiconductor wafer (W) (or dummy wafer (DW)) with respect to the carrier (C) and the dummy carrier (DC). Furthermore, in the form of the carrier (C) and the dummy carrier (DC), in addition to the FOUP (front opening unified pod) that stores the semiconductor wafer (W) in a sealed space, it may be a SMIF (Standard Mechanical Interface) pod or an OC (open cassette) that exposes the stored semiconductor wafer (W) to the outside air.

[0036] Additionally, the watering robot (120) is capable of sliding movement indicated by the arrow (120S) in FIG. 1, turning movement indicated by the arrow (120R), and lifting movement. Accordingly, the watering robot (120) performs the loading and unloading of semiconductor wafers (W) to carriers (C) and dummy carriers (DC), and also performs the loading of semiconductor wafers (W) to alignment units (230) and two cooling units (first cooling unit (130), second cooling unit (140)). The loading and unloading of semiconductor wafers (W) to carriers (C) (or dummy carriers (DC)) by the watering robot (120) is performed by sliding movement of the hand (121) and lifting movement of the carrier (C). Additionally, the watering of the semiconductor wafer (W) between the watering robot (120), the alignment unit (230), the first cooling unit (130), or the second cooling unit (140) is performed by the sliding movement of the hand (121) and the lifting movement of the watering robot (120).

[0037] The alignment unit (230) is installed connected to the side of the indexer unit (101) along the Y-axis direction. The alignment unit (230) is a processing unit that rotates the semiconductor wafer (W) within a horizontal plane to orient it in a direction suitable for flash heating. The alignment unit (230) is configured by installing a mechanism that supports and rotates the semiconductor wafer (W) in a horizontal position, and a mechanism that optically detects a notch or orientation flat formed on the periphery of the semiconductor wafer (W), inside an alignment chamber (231) which is a housing made of aluminum alloy.

[0038] The transfer of the semiconductor wafer (W) to the alignment unit (230) is performed by the transfer robot (120). The semiconductor wafer (W) is transferred from the transfer robot (120) to the alignment chamber (231) so that the center of the wafer is positioned at a predetermined location. In the alignment unit (230), the semiconductor wafer (W) is rotated around a vertical axis with the center of the semiconductor wafer (W) received from the indexer unit (101) as the center of rotation, and the orientation of the semiconductor wafer (W) is adjusted by optically detecting notches, etc. The semiconductor wafer (W) after the orientation adjustment is completed is removed from the alignment chamber (231) by the transfer robot (120).

[0039] A transfer chamber (170) is installed to accommodate the transfer robot (150) as a transfer space for the semiconductor wafer (W) by the transfer robot (150). On three sides of the transfer chamber (170), the processing chamber (6) of the heat treatment unit (160), the first cool chamber (131) of the first cooling unit (130), and the second cool chamber (141) of the second cooling unit (140) are connected. A quartz window (173) is installed in the transfer chamber (170) to allow visibility of the operation of the transfer robot (150).

[0040] The heat treatment unit (160), which is the main part of the substrate processing device (100), is a substrate processing unit that performs flash heat treatment by irradiating a semiconductor wafer (W) that has undergone preheating with a flash (flash light) from a xenon flash lamp (FL). The configuration of this heat treatment unit (160) will be described further later.

[0041] The first cooling unit (130) and the second cooling unit (140) have generally the same configuration. The first cooling unit (130) and the second cooling unit (140) each have a metal cooling plate and a quartz plate placed on the upper surface thereon inside the first cool chamber (131) and the second cool chamber (141), which are housings made of aluminum alloy (all are omitted from illustration). The temperature of the cooling plate is adjusted to room temperature (about 23°C) by means of a Peltier element or constant temperature water circulation. A semiconductor wafer (W) that has undergone flash heat treatment in the heat treatment unit (160) is introduced into the first cool chamber (131) or the second cool chamber (141) and placed on the quartz plate to be cooled.

[0042] Both the first cool chamber (131) and the second cool chamber (141) are connected to each other between the indexer section (101) and the return chamber (170). Two openings are formed in the first cool chamber (131) and the second cool chamber (141) for loading and unloading semiconductor wafers (W). Of the two openings of the first cool chamber (131), the opening connected to the indexer section (101) can be opened and closed by a gate valve (181). Meanwhile, the opening of the first cool chamber (131) connected to the return chamber (170) can be opened and closed by a gate valve (183). That is, the first cool chamber (131) and the indexer (101) are connected through a gate valve (181), and the first cool chamber (131) and the return chamber (170) are connected through a gate valve (183).

[0043] When the semiconductor wafer (W) is transported between the indexer section (101) and the first cool chamber (131), the gate valve (181) is opened. Also, when the semiconductor wafer (W) is transported between the first cool chamber (131) and the return chamber (170), the gate valve (183) is opened. When the gate valve (181) and the gate valve (183) are closed, the interior of the first cool chamber (131) becomes a sealed space.

[0044] Additionally, among the two openings of the second cool chamber (141), the opening connected to the indexer section (101) can be opened and closed by a gate valve (182). Meanwhile, the opening connected to the return chamber (170) of the second cool chamber (141) can be opened and closed by a gate valve (184). That is, the second cool chamber (141) and the indexer section (101) are connected through the gate valve (182), and the second cool chamber (141) and the return chamber (170) are connected through the gate valve (184).

[0045] When the semiconductor wafer (W) is being transported between the indexer section (101) and the second cool chamber (141), the gate valve (182) is opened. Also, when the semiconductor wafer (W) is being transported between the second cool chamber (141) and the return chamber (170), the gate valve (184) is opened. When the gate valve (182) and the gate valve (184) are closed, the interior of the second cool chamber (141) becomes a sealed space. The volume of the first cool chamber (131) and the second cool chamber (141) is smaller than the volume of the return chamber (170) and is about 1 / 10.

[0046] The transfer robot (150) installed in the transfer chamber (170) is pivotable around an axis along the vertical direction as indicated by the arrow (150R). The transfer robot (150) has two link mechanisms consisting of a plurality of arm segments, and transfer hands (151a, 151b) for holding a semiconductor wafer (W) are installed at the ends of each of the two link mechanisms. These transfer hands (151a, 151b) are arranged with a predetermined pitch between them vertically and horizontally, and are each made to slide linearly in the same horizontal direction independently by the link mechanism. In addition, the transfer robot (150) moves the two transfer hands (151a, 151b) up and down while they remain separated by a predetermined pitch by moving the base on which the two link mechanisms are installed up and down.

[0047] When the transfer robot (150) performs the transfer (output / output) of a semiconductor wafer (W) with the first cool chamber (131), the second cool chamber (141), or the processing chamber (6) of the heat treatment unit (160) as the transfer target, first, both transfer hands (151a, 151b) rotate to face the transfer target, and then (or while rotating) move up and down so that one of the transfer hands is positioned at a height to transfer the semiconductor wafer (W) with the transfer target. Then, the transfer hands (151a (151b)) are slid linearly in a horizontal direction to transfer the semiconductor wafer (W) with the transfer target.

[0048] The transfer of the semiconductor wafer (W) between the transfer robot (150) and the transfer robot (120) can be performed through the first cooling unit (130) or the second cooling unit (140). That is, the first cool chamber (131) of the first cooling unit (130) and the second cool chamber (141) of the second cooling unit (140) also function as a pass for transferring the semiconductor wafer (W) between the transfer robot (150) and the transfer robot (120). Specifically, the transfer of the semiconductor wafer (W) is performed by the other receiving the semiconductor wafer (W) that one of the transfer robot (150) or the transfer robot (120) has handed to the first cool chamber (131) or the second cool chamber (141). A conveying mechanism is configured to convey a semiconductor wafer (W) from a carrier (C) to a heat treatment unit (160) by means of a conveying robot (150) and a water robot (120).

[0049] As described above, gate valves (181, 182) are installed between the first cool chamber (131) and the second cool chamber (141) and the indexer section (101), respectively. Additionally, gate valves (183, 184) are installed between the return chamber (170) and the first cool chamber (131) and the second cool chamber (141), respectively. Furthermore, a gate valve (185) is installed between the return chamber (170) and the processing chamber (6) of the heat treatment section (160). When a semiconductor wafer (W) is returned within the substrate processing device (100), these gate valves are opened and closed appropriately.

[0050] Next, the configuration of the heat treatment unit (160) will be described. FIG. 3 is a cross-sectional view showing the configuration of the heat treatment unit (160). The heat treatment unit (160) is provided with a processing chamber (6) that receives a semiconductor wafer (W) and performs heat treatment, a flash lamp house (5) that contains a plurality of flash lamps (FL), and a halogen lamp house (4) that contains a plurality of halogen lamps (HL). The flash lamp house (5) is installed on the upper side of the processing chamber (6), and the halogen lamp house (4) is installed on the lower side. In addition, the heat treatment unit (160) is provided with a holding unit (7) that maintains the semiconductor wafer (W) in a horizontal position inside the processing chamber (6), and a transfer mechanism (10) that performs the transfer of the semiconductor wafer (W) between the holding unit (7) and the transfer robot (150).

[0051] The processing chamber (6) is configured by mounting quartz chamber windows on the upper and lower sides of the cylindrical chamber side (61). The chamber side (61) has a general cylindrical shape with openings at the top and bottom, and the upper opening is closed by mounting an upper chamber window (63), and the lower opening is closed by mounting a lower chamber window (64). The upper chamber window (63), which constitutes the ceiling of the processing chamber (6), is a disc-shaped member formed of quartz and functions as a quartz window that transmits flash light emitted from a flash lamp (FL) into the processing chamber (6). In addition, the lower chamber window (64), which constitutes the bottom of the processing chamber (6), is also a disc-shaped member formed of quartz and functions as a quartz window that transmits light from a halogen lamp (HL) into the processing chamber (6). In addition, the quartz window (173) installed in the return chamber (170) is significantly thinner compared to the upper chamber window (63) and the lower chamber window (64).

[0052] Additionally, a reflective ring (68) is mounted on the upper side of the inner wall of the chamber side (61), and a reflective ring (69) is mounted on the lower side. Both reflective rings (68, 69) are formed in an annular shape. The upper reflective ring (68) is mounted by inserting it from the upper side of the chamber side (61). Meanwhile, the lower reflective ring (69) is mounted by inserting it from the lower side of the chamber side (61) and fixing it with a screw that is not shown. That is, both reflective rings (68, 69) are mounted to the chamber side (61) in a detachable manner. The inner space of the processing chamber (6), that is, the space surrounded by the upper chamber window (63), the lower chamber window (64), the chamber side (61), and the reflective rings (68, 69), is defined as the heat treatment space (65).

[0053] By mounting a reflective ring (68, 69) on the chamber side (61), a recess (62) is formed on the inner wall surface of the processing chamber (6). That is, a recess (62) is formed surrounded by the central part of the inner wall surface of the chamber side (61) where the reflective ring (68, 69) is not mounted, the lower surface of the reflective ring (68), and the upper surface of the reflective ring (69). The recess (62) is formed in a circular shape along the horizontal direction on the inner wall surface of the processing chamber (6) and surrounds a holding portion (7) that holds the semiconductor wafer (W). The chamber side (61) and the reflective ring (68, 69) are formed of a metal material (e.g., stainless steel) with excellent strength and heat resistance.

[0054] Additionally, a conveying opening (furnace opening) (66) is formed on the side of the chamber (61) for bringing in and taking out a semiconductor wafer (W) with respect to the processing chamber (6). The conveying opening (66) can be opened and closed by a gate valve (185). The conveying opening (66) is connected to the outer surface of the concave portion (62). As a result, when the gate valve (185) opens the conveying opening (66), the semiconductor wafer (W) can be brought in from the conveying opening (66) through the concave portion (62) to the heat treatment space (65), and the semiconductor wafer (W) can be taken out from the heat treatment space (65). Also, when the gate valve (185) closes the conveying opening (66), the heat treatment space (65) inside the processing chamber (6) becomes a sealed space.

[0055] Additionally, a gas supply hole (81) for supplying processing gas to a heat treatment space (65) is formed on the upper part of the inner wall of the processing chamber (6). The gas supply hole (81) is formed at a position higher than the concave portion (62) and may also be formed in the reflective ring (68). The gas supply hole (81) is connected to a gas supply pipe (83) through a buffer space (82) formed in an annular shape inside the side wall of the processing chamber (6). The gas supply pipe (83) is connected to a gas supply unit (84). The gas supply unit (84) supplies processing gas to the buffer space (82) through the gas supply pipe (83). The processing gas introduced into the buffer space (82) flows to diffuse within the buffer space (82), where fluid resistance is lower than that of the gas supply hole (81), and is supplied from the gas supply hole (81) into the heat treatment space (65). The treatment gas includes inert gases such as nitrogen (N2), or reactive gases such as ozone (O3), hydrogen (H2), and ammonia (NH3).

[0056] Meanwhile, a gas exhaust hole (86) for exhausting gas within the heat treatment space (65) is formed in the lower part of the inner wall of the processing chamber (6). The gas exhaust hole (86) is formed at a position lower than the concave portion (62) and may also be formed in the reflection ring (69). The gas exhaust hole (86) is connected to a gas exhaust pipe (88) through a buffer space (87) formed in an annular shape inside the side wall of the processing chamber (6). The gas exhaust pipe (88) is connected to an exhaust section (89). The exhaust section (89) exhausts gas within the processing chamber (6) from the gas exhaust hole (86). Additionally, the gas supply hole (81) and the gas exhaust hole (86) may be formed in multiple numbers along the circumferential direction of the processing chamber (6) and may be slit-shaped. The gas supply section (84) and the exhaust section (89) of the heat treatment section (160) will be described in detail later.

[0057] FIG. 4 is a perspective view showing the overall appearance of the retaining part (7). The retaining part (7) is configured to include a support ring (71), a connecting part (72), and a susceptor (74). The support ring (71), the connecting part (72), and the susceptor (74) are all formed of quartz. That is, the entire retaining part (7) is formed of quartz.

[0058] The support ring (71) is an arc-shaped quartz member with a portion missing from the circular shape. This missing portion is formed to prevent interference between the support ring (71) and the material arm (11) of the material mechanism (10) described later. The support ring (71) is supported on the wall of the processing chamber (6) by being placed on the bottom surface of the concave portion (62) (see FIG. 3). On the upper surface of the support ring (71), a plurality of connecting portions (72) (four in this embodiment) are erected and installed along the circumferential direction of the circular shape. The connecting portions (72) are also made of quartz and are fixed to the support ring (71) by welding.

[0059] The susceptor (74) is supported by four connecting parts (72) installed on the support ring (71). FIG. 5 is a plan view of the susceptor (74). FIG. 6 is a cross-sectional view of the susceptor (74). The susceptor (74) is equipped with a retaining plate (75), a guide ring (76), and a plurality of substrate support pins (77). The retaining plate (75) is a roughly circular flat plate-shaped member formed of quartz. The diameter of the retaining plate (75) is larger than the diameter of the semiconductor wafer (W). That is, the retaining plate (75) has a planar size larger than that of the semiconductor wafer (W).

[0060] A guide ring (76) is installed on the upper periphery of the holding plate (75). The guide ring (76) is a toroidal member having an inner diameter larger than the diameter of the semiconductor wafer (W). For example, if the diameter of the semiconductor wafer (W) is φ300 mm, the inner diameter of the guide ring (76) is φ320 mm. The inner circumference of the guide ring (76) is formed as a tapered surface that widens upward from the holding plate (75). The guide ring (76) is formed of the same quartz as the holding plate (75). The guide ring (76) may be welded to the upper surface of the holding plate (75), or it may be fixed to the holding plate (75) by means of a separately processed pin, etc. Alternatively, the holding plate (75) and the guide ring (76) may be processed as a single unit.

[0061] The area of ​​the upper surface of the holding plate (75) that is inner to the guide ring (76) becomes a planar holding surface (75a) that holds the semiconductor wafer (W). A plurality of substrate support pins (77) are erected and installed on the holding surface (75a) of the holding plate (75). In this embodiment, a total of 12 substrate support pins (77) are erected and installed at 30° intervals along the circumference of the outer circle (inner circle of the guide ring (76)) of the holding surface (75a) and the concentric circle. The diameter of the circle in which the 12 substrate support pins (77) are arranged (the distance between opposing substrate support pins (77)) is smaller than the diameter of the semiconductor wafer (W), and if the diameter of the semiconductor wafer (W) is φ300mm, it is φ270mm to φ280mm (φ270mm in this embodiment). Each substrate support pin (77) is formed of quartz. A plurality of substrate support pins (77) may be installed on the upper surface of the retaining plate (75) by welding, or may be processed integrally with the retaining plate (75).

[0062] Returning to FIG. 4, the four connecting parts (72) installed on the support ring (71) and the periphery of the retaining plate (75) of the susceptor (74) are fixed by welding. That is, the susceptor (74) and the support ring (71) are fixedly connected by the connecting parts (72). As the support ring (71) of the retaining part (7) is supported on the wall of the processing chamber (6), the retaining part (7) is mounted in the processing chamber (6). When the retaining part (7) is mounted in the processing chamber (6), the retaining plate (75) of the susceptor (74) is in a horizontal position (a position where the normal coincides with the vertical direction). That is, the retaining surface (75a) of the retaining plate (75) becomes a horizontal plane.

[0063] A semiconductor wafer (W) brought into a processing chamber (6) is placed and maintained in a horizontal position on a susceptor (74) of a holding member (7) mounted in the processing chamber (6). At this time, the semiconductor wafer (W) is supported by 12 substrate support pins (77) installed upright on a holding plate (75) and maintained on the susceptor (74). More strictly, the upper ends of the 12 substrate support pins (77) contact the lower surface of the semiconductor wafer (W) to support the semiconductor wafer (W). Since the height of the 12 substrate support pins (77) (distance from the upper end of the substrate support pins (77) to the holding surface (75a) of the holding plate (75)) is uniform, the semiconductor wafer (W) can be supported in a horizontal position by the 12 substrate support pins (77).

[0064] Additionally, the semiconductor wafer (W) is supported by a plurality of substrate support pins (77) at a predetermined distance from the holding surface (75a) of the holding plate (75). The thickness of the guide ring (76) is greater than the height of the substrate support pins (77). Therefore, horizontal misalignment of the semiconductor wafer (W) supported by the plurality of substrate support pins (77) is prevented by the guide ring (76).

[0065] Additionally, as shown in FIGS. 4 and 5, an opening (78) is formed in the holding plate (75) of the susceptor (74) through vertically. The opening (78) is installed to receive radiation (infrared light) emitted from the lower surface of the semiconductor wafer (W) held in the susceptor (74) by a radiation thermometer (20) (see FIG. 3). That is, the radiation thermometer (20) receives the light emitted from the lower surface of the semiconductor wafer (W) held in the susceptor (74) through the opening (78) to measure the temperature of the semiconductor wafer (W). Furthermore, four through holes (79) are formed in the holding plate (75) of the susceptor (74) through which the lift pin (12) of the material removal mechanism (10), described later, passes to take the semiconductor wafer (W).

[0066] FIG. 7 is a plan view of the material transfer mechanism (10). FIG. 8 is a side view of the material transfer mechanism (10). The material transfer mechanism (10) is equipped with two material transfer arms (11). The material transfer arms (11) are generally shaped like arcs following an annular concave portion (62). Two lift pins (12) are installed on each material transfer arm (11). Each material transfer arm (11) is rotatably moved by a horizontal movement mechanism (13). The horizontal movement mechanism (13) moves a pair of material transfer arms (11) horizontally between a material transfer operation position (solid line position in FIG. 7) where the semiconductor wafer (W) is transferred relative to the holding portion (7) and a withdrawal position (two-dot dashed line position in FIG. 7) where the semiconductor wafer (W) held by the holding portion (7) does not overlap when viewed from a plane. The moving position is below the susceptor (74), and the retreating position is outside the susceptor (74). As for the horizontal movement mechanism (13), each moving arm (11) may be rotated by individual motors, or a pair of moving arms (11) may be rotated in conjunction by one motor using a link mechanism.

[0067] Additionally, a pair of material arms (11) are moved up and down together with a horizontal movement mechanism (13) by a lifting mechanism (14). When the lifting mechanism (14) raises the pair of material arms (11) from the material operation position, a total of four lift pins (12) pass through the through holes (79) (see FIG. 4 and 5) installed in the susceptor (74), and the upper ends of the lift pins (12) protrude from the upper surface of the susceptor (74). Meanwhile, when the lifting mechanism (14) lowers the pair of material arms (11) from the material operation position and pulls the lift pins (12) out of the through holes (79), and the horizontal movement mechanism (13) moves the pair of material arms (11) to open, each material arm (11) moves to the retracted position. The retraction position of a pair of material transfer arms (11) is directly above the support ring (71) of the retaining part (7). Since the support ring (71) is placed on the bottom surface of the concave part (62), the retraction position of the material transfer arms (11) is on the inner side of the concave part (62). In addition, an exhaust mechanism (not shown) is installed near the area where the driving part (horizontal movement mechanism (13) and lifting mechanism (14)) of the material transfer mechanism (10) is installed, and is configured so that the atmosphere around the driving part of the material transfer mechanism (10) is discharged to the outside of the processing chamber (6).

[0068] Returning to FIG. 3, the heat treatment unit (160) is equipped with a radiation thermometer (20) and a pressure gauge (95) as measuring instruments. The radiation thermometer (20) is installed at an oblique angle downward from the semiconductor wafer (W) held in the susceptor (74). The radiation thermometer (20) is a wafer thermometer that receives infrared light emitted from the lower surface of the semiconductor wafer (W) through the opening (78) of the susceptor (74) and measures the temperature of the semiconductor wafer (W) from the intensity of the infrared light. The pressure gauge (95) measures the pressure inside the processing chamber (6). Additionally, for convenience of illustration, FIG. 3 depicts the radiation thermometer (20) and the pressure gauge (95) inside the processing chamber (6), and both are attached to the wall of the processing chamber (6).

[0069] A flash lamp house (5) installed above the processing chamber (6) is configured by having a light source consisting of a plurality (30 in this embodiment) xenon flash lamps (FL) inside the housing (51) and a reflector (52) installed to cover the upper part of the light source. Additionally, a lamp light emission window (53) is mounted on the bottom of the housing (51) of the flash lamp house (5). The lamp light emission window (53) constituting the bottom part of the flash lamp house (5) is a plate-shaped quartz window formed by quartz. As the flash lamp house (5) is installed above the processing chamber (6), the lamp light emission window (53) faces the upper chamber window (63). The flash lamps (FL) irradiate flash light from above the processing chamber (6) into the heat treatment space (65) through the lamp light emission window (53) and the upper chamber window (63).

[0070] A plurality of flash lamps (FL) are each rod-shaped lamps having a long cylindrical shape, and are arranged in a planar shape such that their respective length directions are parallel to each other along the main surface (i.e., along the horizontal direction) of the semiconductor wafer (W) held in the holding portion (7). Therefore, the planar shape formed by the arrangement of the flash lamps (FL) is also a horizontal plane.

[0071] A xenon flash lamp (FL) comprises a rod-shaped glass tube (discharge tube) in which xenon gas is sealed and a positive and negative electrode connected to a capacitor are arranged at both ends, and a trigger electrode installed on the outer surface of the glass tube. Since xenon gas is an electrical insulator, electricity does not flow within the glass tube under normal conditions, even if charge is accumulated in the capacitor. However, when a high voltage is applied to the trigger electrode to break the insulation, the electricity accumulated in the capacitor flows into the glass tube instantaneously, and light is emitted by the excitation of xenon atoms or molecules at that time. In this xenon flash lamp (FL), the electrostatic energy previously accumulated in the capacitor is converted into a very short light pulse of 0.1 milliseconds to 100 milliseconds, and thus has the characteristic of being able to irradiate very strong light to a light source that is continuously lit, such as a halogen lamp (HL). That is, a flash lamp (FL) is a pulse-emitting lamp that emits light instantaneously in a very short time of less than 1 second.

[0072] The flash power supply that supplies power to the flash lamp (FL) is equipped with an IGBT (insulated gate bipolar transistor) in addition to the capacitor mentioned above. By adjusting the waveform of the pulse applied to the gate of the IGBT, the light emission time of the flash lamp (FL) can be set between 0.1 milliseconds and 100 milliseconds.

[0073] Additionally, the reflector (52) is installed above the plurality of flash lamps (FL) to cover the entirety of them. The basic function of the reflector (52) is to reflect the flash light emitted from the plurality of flash lamps (FL) toward the heat treatment space (65). The reflector (52) is formed from an aluminum alloy plate, and its surface (the side facing the flash lamp (FL)) is roughened by blast treatment.

[0074] The halogen lamp housing (4) installed below the processing chamber (6) contains a plurality of halogen lamps (HL) (40 in this embodiment) inside the housing (41). The plurality of halogen lamps (HL) irradiate light into the heat treatment space (65) through the lower chamber window (64) from below the processing chamber (6).

[0075] FIG. 9 is a plan view showing the arrangement of multiple halogen lamps (HL). In this embodiment, 20 halogen lamps (HL) are arranged in each of the upper and lower two sections. Each halogen lamp (HL) is a rod-shaped lamp having a long cylindrical shape. Both the upper and lower sections, with 20 halogen lamps (HL), are arranged so that their respective length directions are parallel to each other along the main surface (i.e., along the horizontal direction) of the semiconductor wafer (W) held in the holding section (7). Therefore, the plane formed by the arrangement of the halogen lamps (HL) in both the upper and lower sections is a horizontal plane.

[0076] Also, as shown in FIG. 9, the density of the arrangement of halogen lamps (HL) is higher in the region facing the periphery than in the region facing the center of the semiconductor wafer (W) held in the holding portion (7) at both the top and bottom. That is, for both the top and bottom, the arrangement pitch of the halogen lamps (HL) is shorter in the periphery than in the center of the lamp arrangement. As a result, a greater amount of light can be irradiated to the periphery of the semiconductor wafer (W), where a temperature drop is likely to occur during heating by light irradiation from the halogen lamps (HL).

[0077] In addition, a group of lamps consisting of upper halogen lamps (HL) and a group of lamps consisting of lower halogen lamps (HL) are arranged to intersect in a grid shape. That is, a total of 40 halogen lamps (HL) are arranged so that the length direction of each upper halogen lamp (HL) and the length direction of each lower halogen lamp (HL) are orthogonal.

[0078] A halogen lamp (HL) is a filament-type light source that emits light by incandescently heating a filament placed inside a glass tube through an electric current. Inside the glass tube, a gas is sealed in which a small amount of halogen elements (iodine, bromine, etc.) is introduced into an inert gas such as nitrogen or argon. By introducing halogen elements, it becomes possible to set the temperature of the filament to a high temperature while suppressing breakage of the filament. Therefore, the halogen lamp (HL) has the characteristics of having a longer lifespan than a conventional incandescent bulb and being able to continuously emit strong light. That is, the halogen lamp (HL) is a continuous-lighting lamp that emits light continuously for at least one second. In addition, the halogen lamp (HL) has a long lifespan because it is a rod-shaped lamp, and by arranging the halogen lamp (HL) in a horizontal direction, it achieves excellent radiation efficiency toward an upper semiconductor wafer (W).

[0079] In addition, a reflector (43) is installed below the two-stage halogen lamp (HL) inside the housing (41) of the halogen lamp house (4) (Fig. 3). The reflector (43) reflects light emitted from the plurality of halogen lamps (HL) toward the heat treatment space (65).

[0080] In addition to the above configuration, the heat treatment unit (160) is equipped with various cooling structures to prevent an excessive temperature rise in the halogen lamp house (4), flash lamp house (5), and processing chamber (6) caused by thermal energy generated from the halogen lamp (HL) and flash lamp (FL) during the heat treatment of the semiconductor wafer (W). For example, a water cooling pipe (not shown) is installed in the wall of the processing chamber (6). Also, the halogen lamp house (4) and the flash lamp house (5) are air-cooled structures that form a gas flow inside to dissipate heat. Additionally, air is supplied to the gap between the upper chamber window (63) and the lamp light emission window (53) to cool the flash lamp house (5) and the upper chamber window (63).

[0081] FIG. 10 is a schematic diagram showing the supply and exhaust mechanism for the processing chamber (6) and the return chamber (170). The processing chamber (6) of the heat treatment unit (160) is connected to one side of the return chamber (170). The opening (return opening (66)) connecting the processing chamber (6) and the return chamber (170) is opened and closed by a gate valve (185). When the gate valve (185) closes the return opening (66), an O-ring (186) is inserted between the two, sealing the internal space (heat treatment space (65)) of the processing chamber (6). That is, the processing chamber (6) and the return chamber (170) are connected through the gate valve (185) and the O-ring (186).

[0082] A gas supply unit (first gas supply unit) (84) that supplies processing gas to a processing chamber (6) is equipped with valves (111, 113), an inert gas supply source (112), and a reactive gas supply source (114). The end of a gas supply pipe (83) connected to the processing chamber (6) is branched into two branches, one of which is connected to the inert gas supply source (112) and the other is connected to the reactive gas supply source (114). A valve (111) is installed in the branch pipe connected to the inert gas supply source (112), and a valve (113) is installed in the branch pipe connected to the reactive gas supply source (114). When the valve (111) is opened, an inert gas (e.g., nitrogen) is supplied from the inert gas supply source (112) to the heat treatment space (65) inside the processing chamber (6). Meanwhile, when valve (113) is opened, reactive gas (e.g., ammonia) is supplied into the treatment chamber (6) from the reactive gas supply source (114). That is, the gas supply unit (84) supplies reactive gas or inert gas to the treatment chamber (6). In addition, by opening both valve (111) and valve (113), it is also possible to supply a mixed gas of reactive gas and inert gas to the treatment chamber (6).

[0083] An exhaust unit (89) for exhausting gas from a processing chamber (6) is equipped with valves (211, 213), an exhaust line (212), and a vacuum pump (214). The front end of a gas exhaust pipe (88), which has its tip connected to the processing chamber (6), is branched into two branches, one of which is connected to the exhaust line (212) and the other is connected to the vacuum pump (214). The exhaust line (212) is connected to an exhaust system provided in a factory where a substrate processing device (100) is installed. A valve (211) is installed in the branch pipe connected to the exhaust line (212), and a valve (213) is installed in the branch pipe connected to the vacuum pump (214). When the valve (211) is opened, the gas inside the processing chamber (6) is discharged into the exhaust line (212). Meanwhile, when the valve (213) is opened while the vacuum pump (214) is operating, gas is exhausted from the processing chamber (6), and the pressure inside the processing chamber (6) is reduced to below atmospheric pressure. That is, the exhaust unit (89) includes a vacuum pump (214) that exhausts gas from the processing chamber (6) and reduces the pressure inside the processing chamber (6) to below atmospheric pressure.

[0084] Additionally, a pressure gauge (first pressure gauge) (95) is installed in the processing chamber (6). The pressure gauge (95) measures the pressure of the gas inside the processing chamber (6).

[0085] Additionally, a gas detector (first gas detection unit) (251) is connected to the processing chamber (6) through a sampling pipe (252). A valve (253) is installed in the sampling pipe (252). When the valve (253) is opened, the gas inside the processing chamber (6) flows into the gas detector (251), and the concentration of the reactive gas inside the processing chamber (6) is measured. A pump for sucking gas inside the processing chamber (6) may be installed in the gas detector (251).

[0086] Meanwhile, a gas supply unit (second gas supply unit) (350) is connected to the return chamber (170) through a gas supply pipe (351). The gas supply unit (350) is equipped with a valve (352) and an inert gas supply source (353). The front end of the gas supply pipe (351) is connected to the return chamber (170), and the rear end is connected to the inert gas supply source (353). A valve (352) is installed in the middle of the path of the gas supply pipe (351). When the valve (352) is opened, an inert gas (e.g., nitrogen) is supplied from the inert gas supply source (353) to the return chamber (170). That is, the gas supply unit (350) supplies inert gas to the return chamber (170).

[0087] An exhaust section (370) is connected to the return chamber (170) through a gas exhaust pipe (371). The exhaust section (370) of the return chamber (170) is equipped with a pressure regulating valve (372) and an exhaust line (373). The tip of the gas exhaust pipe (371) is connected to the return chamber (170), and the tip is connected to the exhaust line (373). A pressure regulating valve (372) is installed along the path of the gas exhaust pipe (371). The exhaust line (373) is connected to an exhaust system provided in a factory where the substrate processing device (100) is installed. The pressure regulating valve (372) controls the exhaust flow rate so that the pressure of the gas inside the return chamber (170) maintains a preset constant value. Accordingly, the exhaust section (370) exhausts gas from the return chamber (170) so that the inside of the return chamber (170) becomes a constant pressure.

[0088] A gas detector (second gas detection unit) (391) is connected via a sampling pipe (392) along the path of the gas exhaust pipe (371). The sampling pipe (392) is a path of the gas exhaust pipe (371) and is connected between the return chamber (170) and the pressure regulating valve (372). A valve (393) is installed in the sampling pipe (392). When the valve (393) is opened, gas inside the return chamber (170) flows from the gas exhaust pipe (371) through the sampling pipe (392) to the gas detector (391), and the concentration of the reactive gas inside the return chamber (170) is measured. A pump that sucks gas from the gas exhaust pipe (371) may be installed in the gas detector (391).

[0089] Additionally, a pressure gauge (second pressure gauge) (380) is installed in the return chamber (170). The pressure gauge (380) measures the pressure of the gas inside the return chamber (170).

[0090] The control unit (3) controls the various operating mechanisms installed in the substrate processing device (100). In FIG. 1, the control unit (3) is shown within the indexer unit (101), but is not limited thereto, and the control unit (3) can be placed at any location within the substrate processing device (100).

[0091] FIG. 11 is a block diagram showing the configuration of the control unit (3). The hardware configuration of the control unit (3) is the same as that of a general computer. That is, the control unit (3) is equipped with a CPU, which is a circuit that performs various calculation processing; a ROM, which is a read-only memory that stores a basic program; a RAM, which is a read-write memory that stores various information; and a storage unit (34) (e.g., a magnetic disk or SSD) that stores control software or data. Processing in the board processing device (100) proceeds by the CPU of the control unit (3) executing a predetermined processing program. In addition, a timer (38) having a timing function is installed in the control unit (3).

[0092] Additionally, elements such as a pressure gauge (95, 380), various valves, a gate valve (185), and a vacuum pump (214) are electrically connected to the control unit (3). In addition to the measurement results of the pressure gauge (95, 380) being transmitted to the control unit (3), the control unit (3) controls the operation of the gas supply unit (84), the exhaust unit (89) including the vacuum pump (214), and the gas supply unit (350).

[0093] Additionally, a display unit (33) and an input unit (32) are connected to the control unit (3). The display unit (33) and the input unit (32) function as user interfaces for the substrate processing device (100). The control unit (3) displays various information on the display unit (33). The operator of the substrate processing device (100) can input various commands or parameters from the input unit (32) while checking the information displayed on the display unit (33). For example, a keyboard or a mouse can be used as the input unit (32). For example, a liquid crystal display can be used as the display unit (33). In this embodiment, a liquid crystal touch panel installed on the outer wall of the substrate processing device (100) is adopted as the display unit (33) and the input unit (32) to combine both functions. Accordingly, the display unit (33) and the input unit (32) constitute a GUI (Graphical User Interface) in the substrate processing device (100).

[0094] Next, the processing operation of the substrate processing device (100) according to the present invention will be described. The processing procedure in the substrate processing device (100) described below is carried out by the control unit (3) controlling each operating mechanism of the substrate processing device (100).

[0095] First, multiple unprocessed semiconductor wafers (product wafers) (W) are placed in the first load port (110a) or the second load port (110b) of the indexer unit (101) while the unprocessed semiconductor wafers (W) are contained in the carrier (C). Then, a water robot (120) takes out the unprocessed semiconductor wafers (W) one by one from the carrier (C) and brings them into the alignment chamber (231) of the alignment unit (230). In the alignment chamber (231), the semiconductor wafer (W) is rotated around a vertical axis within a horizontal plane with its center as the center of rotation, and the orientation of the semiconductor wafer (W) is adjusted by optically detecting notches, etc.

[0096] Next, the water robot (120) of the indexer unit (101) takes out the oriented semiconductor wafer (W) from the alignment chamber (231) and brings it into the first cool chamber (131) of the first cooling unit (130) or the second cool chamber (141) of the second cooling unit (140). In this embodiment, the semiconductor wafer (W) is described as being brought into the first cool chamber (131), but the same applies when it is brought into the second cool chamber (141). The first cool chamber (131) temporarily holds the unprocessed semiconductor wafer (W) to be returned to the return chamber (170). Then, the semiconductor wafer (W) inside the first cool chamber (131) is transferred to the return chamber (170) by the return robot (150). When an unprocessed semiconductor wafer (W) is transferred from the indexer section (101) to the return chamber (170) via the first cool chamber (131) or the second cool chamber (141), the first cool chamber (131) and the second cool chamber (141) function as a pass for the semiconductor wafer (W).

[0097] The transfer robot (150), having removed the semiconductor wafer (W) from the first cool chamber (131), turns toward the processing chamber (6) of the heat treatment unit (160). Subsequently, the gate valve (185) opens the space between the processing chamber (6) and the transfer chamber (170). Then, the transfer robot (150) brings the unprocessed semiconductor wafer (W) into the processing chamber (6). At this time, if the semiconductor wafer (W) that has undergone the preceding heat treatment is present in the processing chamber (6), the semiconductor wafer (W) after heat treatment is removed by one of the transfer hands (151a, 151b), and then the unprocessed semiconductor wafer (W) is brought into the processing chamber (6) to perform wafer replacement. After that, the gate valve (185) closes the space between the processing chamber (6) and the transfer chamber (170).

[0098] A semiconductor wafer (W) introduced into a processing chamber (6) is preheated by a halogen lamp (HL), and then flash heating treatment is performed by flash light irradiation from a flash lamp (FL). In addition, the flash heating treatment of this embodiment is carried out, for example, in an ammonia atmosphere under reduced pressure.

[0099] After the flash heating process is finished, the gate valve (185) opens the space between the processing chamber (6) and the return chamber (170) again. Then, the return robot (150) takes the semiconductor wafer (W) after the flash heating process out of the processing chamber (6) to the return chamber (170). The return robot (150) that has taken out the semiconductor wafer (W) turns away from the processing chamber (6) toward the first cool chamber (131) or the second cool chamber (141). Also, the gate valve (185) closes the space between the processing chamber (6) and the return chamber (170).

[0100] After that, the transport robot (150) transports the semiconductor wafer (W) after heat treatment to the first cool chamber (131) of the first cooling unit (130) or the second cool chamber (141) of the second cooling unit (140). In this embodiment, the semiconductor wafer (W) after heat treatment is described as being transported to the second cool chamber (141), but the same applies when it is transported to the first cool chamber (131). The second cool chamber (141) holds and cools the semiconductor wafer (W) after heat treatment that has been transported from the transport chamber (170). Since the temperature of the entire semiconductor wafer (W) at the time of being removed from the processing chamber (6) of the heat treatment unit (160) is relatively high, it is cooled to near room temperature in the second cool chamber (141).

[0101] After a predetermined cooling time has elapsed, the water robot (120) removes the semiconductor wafer (W) after cooling from the second cool chamber (141) and returns it to the carrier (C). When a predetermined number of processed semiconductor wafers (W) are received in the carrier (C), the carrier (C) is removed from the first load port (110a) or the second load port (110b) of the indexer unit (101).

[0102] The explanation regarding the heat treatment in the heat treatment section (160) continues. First, prior to the processing of the semiconductor wafer (W), the valve (111) for supplying air is opened, and the valve (211) for exhausting air is opened, thereby initiating the supply and exhaust of the processing chamber (6). When the valve (111) is opened, nitrogen gas is supplied to the heat treatment space (65) from the gas supply hole (81). Also, when the valve (211) is opened, the gas inside the processing chamber (6) is exhausted from the gas exhaust hole (86). As a result, the nitrogen gas supplied from the upper part of the heat treatment space (65) inside the processing chamber (6) flows downward and is exhausted from the lower part of the heat treatment space (65).

[0103] Next, the gate valve (185) is opened so that the return opening (66) is opened, and the return robot (150) brings the unprocessed semiconductor wafer (W) through the return opening (66) into the heat treatment space (65) within the processing chamber (6). The return robot (150) advances the return hand (151a) (or return hand (151b)) holding the unprocessed semiconductor wafer (W) to a position just above the holding part (7) and stops it. Then, as the pair of transfer arms (11) of the transfer mechanism (10) move horizontally from the withdrawal position to the transfer operation position and rise, the lift pin (12) passes through the through hole (79) and protrudes from the upper surface of the holding plate (75) of the susceptor (74) to receive the semiconductor wafer (W). At this time, the lift pin (12) rises above the top of the substrate support pin (77).

[0104] After the unprocessed semiconductor wafer (W) is placed on the lift pin (12), the transfer robot (150) removes the transfer hand (151a) from the heat treatment space (65), and the transfer opening (66) is closed by the gate valve (185). Then, as a pair of transfer arms (11) descend, the semiconductor wafer (W) is transferred from the transfer mechanism (10) to the susceptor (74) of the holding unit (7) and held from below in a horizontal position. The semiconductor wafer (W) is supported by a plurality of substrate support pins (77) installed upright on the holding plate (75) and held in the susceptor (74). Additionally, the semiconductor wafer (W) is held in the holding unit (7) with the surface to be subjected to flash heat treatment as the upper surface. A predetermined gap is formed between the back side of the semiconductor wafer (W) (the main surface opposite to the surface) and the holding surface (75a) of the holding plate (75) by being supported by a plurality of substrate support pins (77). A pair of material arms (11) that have descended to the lower side of the susceptor (74) are retracted to a retracted position, that is, into the inner side of the concave portion (62), by the horizontal movement mechanism (13).

[0105] A semiconductor wafer (W) is introduced into the processing chamber (6), and the return opening (66) is closed by the gate valve (185) so that the heat treatment space (65) becomes a sealed space, after which the pressure inside the processing chamber (6) is reduced to less than atmospheric pressure. Specifically, in addition to closing the valve (111) and the valve (211), the valve (213) is opened while the vacuum pump (214) is operated, and the gas inside the processing chamber (6) is exhausted to reduce the pressure inside the processing chamber (6) to a processing pressure less than atmospheric pressure. The processing pressure can be set to an appropriate value depending on the processing content, for example, 100 Pa or more and 5000 Pa or less.

[0106] Additionally, while depressurizing the inside of the processing chamber (6), the valve (113) is opened to supply ammonia into the processing chamber (6). At this time, the valve (111) may also be opened simultaneously to supply a mixed gas of ammonia and nitrogen into the processing chamber (6). As a result, an ammonia atmosphere in a depressurized state is formed in the heat treatment space (65) inside the processing chamber (6). Furthermore, if the exhaust flow rate from the exhaust unit (89) is greater than the gas supply flow rate from the gas supply unit (84), it is possible to form an ammonia atmosphere inside the processing chamber (6) while depressurizing the inside of the processing chamber (6).

[0107] As the pressure inside the processing chamber (6) is reduced to a predetermined processing pressure and an ammonia atmosphere is formed inside the processing chamber (6), 40 halogen lamps (HL) are simultaneously lit to initiate preheating (assist heating). Halogen light emitted from the halogen lamps (HL) passes through the lower chamber window (64) and susceptor (74) formed of quartz and is irradiated from the lower surface of the semiconductor wafer (W). By receiving light irradiation from the halogen lamps (HL), the semiconductor wafer (W) is preheated and its temperature rises. Additionally, since the material arm (11) of the material transfer mechanism (10) is retracted into the inner side of the concave portion (62), there is no obstruction to heating by the halogen lamps (HL).

[0108] When preheating is performed using a halogen lamp (HL), the temperature of the semiconductor wafer (W) is measured by a radiation thermometer (20). That is, the radiation thermometer (20) receives infrared light emitted through an opening (78) from the lower surface of the semiconductor wafer (W) held in the susceptor (74) and measures the temperature of the wafer being heated. The measured temperature of the semiconductor wafer (W) is transmitted to the control unit (3). The control unit (3) controls the output of the halogen lamp (HL) while monitoring whether the temperature of the semiconductor wafer (W), which is being heated by light irradiation from the halogen lamp (HL), has reached a predetermined preheating temperature (T1). That is, the control unit (3) feedback controls the output of the halogen lamp (HL) based on the measurement value from the radiation thermometer (20) so that the temperature of the semiconductor wafer (W) becomes the preheating temperature (T1).

[0109] After the temperature of the semiconductor wafer (W) reaches the preheating temperature (T1), the control unit (3) maintains the semiconductor wafer (W) at the preheating temperature (T1) for a while. Specifically, when the temperature of the semiconductor wafer (W) measured by the radiation thermometer (20) reaches the preheating temperature (T1), the control unit (3) adjusts the output of the halogen lamp (HL) to maintain the temperature of the semiconductor wafer (W) at approximately the preheating temperature (T1).

[0110] By performing preheating with such halogen lamps (HL), the entire semiconductor wafer (W) is uniformly heated to a preheating temperature (T1). In the preheating stage using halogen lamps (HL), the temperature of the periphery of the semiconductor wafer (W), where heat dissipation is more likely to occur, tends to decrease compared to the center; however, the density of the halogen lamps (HL) in the halogen lamp house (4) is higher in the area facing the periphery than in the area facing the center of the semiconductor wafer (W). As a result, the amount of light irradiated to the periphery of the semiconductor wafer (W), where heat dissipation is more likely to occur, is increased, and the in-plane temperature distribution of the semiconductor wafer (W) during the preheating stage can be made uniform.

[0111] When the temperature of the semiconductor wafer (W) reaches the preheating temperature (T1) and a predetermined time has elapsed, a flash lamp (FL) irradiates flash light onto the surface of the semiconductor wafer (W). At this time, some of the flash light emitted from the flash lamp (FL) is directed directly into the processing chamber (6), and other parts are reflected by the reflector (52) and then directed into the processing chamber (6), and flash heating of the semiconductor wafer (W) is performed by the irradiation of these flash lights.

[0112] Flash heating is performed by irradiating flash light (spark) from a flash lamp (FL), so the surface temperature of the semiconductor wafer (W) can be raised in a short time. That is, the flash light irradiated from the flash lamp (FL) is a very short and strong flash with an irradiation time of about 0.1 milliseconds or more and 100 milliseconds or less, in which electrostatic energy previously collected in a capacitor is converted into a very short light pulse. By irradiating the surface of the semiconductor wafer (W) with such a very short irradiation time and high intensity flash light, the surface temperature rises instantaneously to the processing temperature (T2). The processing temperature (T2) is higher than the preheating temperature (T1). Then, the surface temperature of the semiconductor wafer (W) rapidly decreases as soon as it reaches the processing temperature (T2). By performing flash heating of the semiconductor wafer (W) in an ammonia atmosphere, surface treatment (e.g., nitriding treatment) is performed on the semiconductor wafer (W).

[0113] After the flash heating process is finished, the halogen lamp (HL) is turned off after a predetermined time has elapsed. As a result, the semiconductor wafer (W) is rapidly lowered from the preheating temperature (T1). The temperature of the semiconductor wafer (W) being lowered is measured by a radiation thermometer (20), and the measurement result is transmitted to the control unit (3). Also, after the flash heating process is finished, the valve (113) and the valve (213) are closed, and the valve (111) and the valve (211) are opened. As a result, ammonia is gradually discharged from the processing chamber (6), and the ammonia atmosphere is replaced with a nitrogen atmosphere, and the pressure inside the processing chamber (6) is restored to atmospheric pressure.

[0114] After the pressure inside the processing chamber (6) is reduced to atmospheric pressure, the control unit (3) monitors whether the temperature of the semiconductor wafer (W) has been lowered to a predetermined temperature based on the measurement result of the radiation thermometer (20). Then, after the temperature of the semiconductor wafer (W) has been lowered to a predetermined temperature or lower, a pair of transfer arms (11) of the transfer mechanism (10) are horizontally moved from the withdrawal position to the transfer operation position and rise, so that the lift pin (12) protrudes from the upper surface of the susceptor (74) and receives the semiconductor wafer (W) after heat treatment from the susceptor (74). Next, the return opening (66), which was closed by the gate valve (185), is opened, and the processed semiconductor wafer (W) placed on the lift pin (12) is transferred to the return chamber (170) by the return hand (151b) (or return hand (151a)) of the return robot (150), and the processing in the heat treatment unit (160) is completed.

[0115] When heat treatment of a semiconductor wafer (W) is performed in the heat treatment unit (160), the pressure inside the treatment chamber (6) is reduced to less than atmospheric pressure, and light irradiation is performed on the semiconductor wafer (W) while an ammonia atmosphere is formed inside the treatment chamber (6). Meanwhile, while heat treatment of the semiconductor wafer (W) is being performed in the heat treatment unit (160), the inside of the return chamber (170) is continuously maintained at atmospheric pressure. That is, although a pressure difference occurs inside the treatment chamber (6) and inside the return chamber (170), the return opening (66) connecting the treatment chamber (6) and the return chamber (170) is closed by a gate valve (185), and the gate valve (185) and the return opening (66) are sealed by an O-ring (186). Therefore, gas does not flow from the relatively high-pressure return chamber (170) to the low-pressure treatment chamber (6), and harmful ammonia in the treatment chamber (6) is also prevented from leaking into the return chamber (170).

[0116] However, when the O-ring (186) is damaged, a rapid gas transfer occurs from the return chamber (170) to the processing chamber (6), causing the pressure inside the return chamber (170) to decrease and the quartz window (173) may be damaged. In addition, while the upper chamber window (63) and lower chamber window (64) of the processing chamber (6) are of a significantly thick pressure-resistant specification, the thickness of the quartz window (173) is relatively thin as it is not intended for use under reduced pressure. Also, if the O-ring (186) is damaged, it is assumed that ammonia inside the processing chamber (6) will leak into the return chamber (170).

[0117] For this reason, in the present embodiment, a response to the case where the O-ring (186) is damaged is performed as follows. FIG. 12 is a flowchart showing the procedure for pressure control in the case where the O-ring (186) is damaged. First, as described above, an unprocessed semiconductor wafer (W) is brought into the processing chamber (6) by the transport robot (150) (step S11). Then, heat treatment of the semiconductor wafer (W) is performed in the processing chamber (6) following the procedure described above (step S12). During the heat treatment, light irradiation is performed on the semiconductor wafer (W) while the pressure inside the processing chamber (6) is reduced to below atmospheric pressure and an ammonia atmosphere is formed inside the processing chamber (6).

[0118] While the heat treatment of a semiconductor wafer (W) is being performed in the processing chamber (6), a pressure gauge (380) measures the pressure of the gas in the return chamber (170). The control unit (3) monitors whether the pressure value in the return chamber (170) measured by the pressure gauge (380) has not fallen below a predetermined threshold value (step S13, step S14). If there is no particular abnormality, the pressure in the return chamber (170) is generally maintained at atmospheric pressure by the pressure regulating valve (372), and if the pressure in the return chamber (170) measured by the pressure gauge (380) is greater than the second threshold value (Th2), the process returns from step S13 to step S12 and the heat treatment continues. The second threshold value (Th2) is, for example, a value 1 kPa lower than atmospheric pressure.

[0119] Meanwhile, when the measured value of the pressure gauge (380) is less than or equal to the second threshold value (Th2), the process proceeds from step S13 to step S14, and the pressure inside the return chamber (170) and the first threshold value (Th1) are compared and determined by the control unit (3). The first threshold value (Th1) is, for example, a value 5 kPa lower than atmospheric pressure.

[0120] If the pressure inside the return chamber (170) measured by the pressure gauge (380) is below the second threshold value (Th2) and also greater than the first threshold value (Th1), the process proceeds from step S14 to step S15 and is treated as a pressure abnormality in the return path. In such cases, a mild pressure abnormality occurs in the return chamber (170), and the cause is assumed to be an abnormality in the exhaust section (370) rather than a breakage of the O-ring (186). For example, if an abnormality occurs in the factory exhaust connected to the exhaust line (373), a mild pressure abnormality occurs in the return chamber (170) even if the O-ring (186) is not broken.

[0121] When proceeding to step S15, the heat treatment of the semiconductor wafer (W) being performed in the processing chamber (6) continues as is. Therefore, the necessary treatment for the semiconductor wafer (W) is completed, thereby preventing processing defects. However, after the semiconductor wafer (W) that has completed a series of heat treatments is removed from the processing chamber (6), the subsequent semiconductor wafer (W) is prohibited by the control unit (3) from being brought into the processing chamber (6). After that, for example, a verification operation of the exhaust unit (370) is performed.

[0122] Meanwhile, if the pressure inside the return chamber (170) measured by the pressure gauge (380) is below the first threshold value (Th1), the process proceeds from step S14 to step S16, and the pressure treatment of the processing chamber (6) is performed. In this case, it is highly likely that the gas inside the return chamber (170) has been rapidly sucked in by the processing chamber (6) in a reduced pressure state due to damage to the O-ring (186). As a result, the heating treatment of the semiconductor wafer (W) inside the processing chamber (6) is immediately stopped, and the pressure treatment of the processing chamber (6) is performed.

[0123] In the pressure treatment of step S16, specifically, the control unit (3) stops the vacuum pump (214) that is depressurizing the treatment chamber (6) and closes the valve (213). By doing so, the pressure reduction of the treatment chamber (6) is stopped. Also, the control unit (3) closes the valve (113) to stop the supply of ammonia to the treatment chamber (6). Additionally, the control unit (3) opens the valve (111) and the valve (211). By doing so, nitrogen is supplied into the treatment chamber (6), and the treatment chamber (6) is pressured to atmospheric pressure, harmful ammonia is discharged from the treatment chamber (6), and an atmosphere change from an ammonia atmosphere to a nitrogen atmosphere proceeds.

[0124] In addition to stopping the depressurization of the processing chamber (6), nitrogen is supplied into the processing chamber (6) to restore the pressure inside the processing chamber (6) to atmospheric pressure, thereby reducing the pressure difference between the processing chamber (6) and the return chamber (170), so that the pressure inside the return chamber (170) can be suppressed. As a result, damage to the quartz window (173) can be prevented in advance. Furthermore, in step S14, the quartz window (173) is not damaged when the pressure inside the return chamber (170) is reduced to a first threshold value (Th1) (atmospheric pressure - 5 kPa in this embodiment).

[0125] In this embodiment, the pressure treatment of the return chamber (170) is also performed in parallel with the pressure treatment of the processing chamber (6) (step S17). Specifically, the control unit (3) opens the valve (352) to continue supplying nitrogen to the return chamber (170). In addition, the pressure regulating valve (372) adjusts the exhaust flow rate to the exhaust line (373) so that the pressure inside the return chamber (170) becomes atmospheric pressure. As a result, nitrogen is supplied into the return chamber (170) as well, and the inside of the return chamber (170) is pressured to atmospheric pressure. By pressured to atmospheric pressure not only in the processing chamber (6) but also in the return chamber (170), the pressure difference between the processing chamber (6) and the return chamber (170) is further reduced, making it more reliable to prevent the inside of the return chamber (170) from being severely depressurized.

[0126] Even if the interior of the processing chamber (6) and the return chamber (170) is restored to atmospheric pressure, if the pressure inside the return chamber (170) in step S14 is determined to be below the first threshold value (Th1), the heat treatment of the semiconductor wafer (W) is interrupted midway. Normally, such semiconductor wafers (W) become defective. Therefore, it is necessary to recover the semiconductor wafer (W) from the processing chamber (6). To do so, it is necessary to open the gate valve (185). If the gate valve (185) is opened while ammonia remains in the processing chamber (6), there is a risk that dangerous ammonia will leak from the processing chamber (6) to the return chamber (170). Accordingly, in this embodiment, the concentration of the reactive gas remaining in the processing chamber (6) is checked (step S18).

[0127] FIG. 13 is a flowchart showing the procedure for checking residual gas in the processing chamber (6). FIG. 14 is a diagram showing an example of a GUI displayed on a display unit (33) (a touch panel in this embodiment) when performing a residual gas check. In FIG. 14, “CL1-CR” represents a gate valve (183) between the first cool chamber (131) and the return chamber (170), “CL2-CR” represents a gate valve (184) between the second cool chamber (141) and the return chamber (170), and “PCH-CR” represents a gate valve (185) between the processing chamber (6) and the return chamber (170) (see FIG. 1). For the gate valve (183) and the gate valve (184), both an “Open” button and a “Close” button are selectable. Meanwhile, regarding the gate valve (185), the “Close” button (502) is selectable before the residual gas check is performed, whereas the “Open” button (501) is not selectable (for example, it is displayed as grayout). That is, even after the processing chamber (6) is pressurized to atmospheric pressure, the opening of the gate valve (185) is prohibited unless the concentration check of the reactive gas inside the processing chamber (6) is performed.

[0128] When an operator of the substrate processing device (100) selects and presses the “Residual check” button (503) from the GUI of FIG. 14, the residual gas check of FIG. 13 is initiated. First, the pressure inside the processing chamber (6) is measured by the pressure gauge (95), and the control unit (3) determines whether the measurement result is, for example, 90 kPa or less (step S21). If the pressure inside the processing chamber (6) is 90 kPa or less, the gas detector (251) cannot draw in the gas inside the processing chamber (6) even if the valve (253) is opened, so concentration measurement is impossible. Consequently, if the pressure inside the processing chamber (6) is 90 kPa or less, the process proceeds from step S21 to step S22, and the residual gas check is stopped by displaying an error on the display unit (33).

[0129] If the pressure inside the processing chamber (6) measured by the pressure gauge (95) is greater than 90 kPa, step S21 proceeds to step S23, and the concentration of the reactive gas (ammonia in this embodiment) remaining inside the processing chamber (6) is measured. Specifically, the control unit (3) opens the valve (253) so that the gas detector (251) begins sampling the gas inside the processing chamber (6) (step S24). The gas detector (251) measures the concentration of ammonia in the gas flowing in from the processing chamber (6). Additionally, the valve (253) is closed except when sampling is performed.

[0130] Sampling by the gas detector (251) is initiated, and at the same time, timing by the timer (38) is initiated (step S25). The timer (38) performs timing for, for example, 60 seconds (step S26). If 60 seconds have not elapsed since the timing by the timer (38) was initiated, the process proceeds from step S26 to step S27 to reduce the remaining waiting time, and returns to step S26. That is, a waiting state is established in which steps S26 and S27 are repeated until 60 seconds have elapsed since the timing by the timer (38) was initiated. Additionally, the waiting time for concentration measurement is not limited to 60 seconds and can be set to an appropriate value.

[0131] FIG. 15 is a diagram showing an example of a GUI displayed on a display unit (33) during the waiting period for concentration measurement. The remaining waiting time is displayed on the display unit (33). Additionally, when the operator presses the “Cancel” button, the valve (253) is closed and the concentration measurement is stopped.

[0132] Valves (111) and (211) are open during the concentration measurement phase. As a result, nitrogen is continuously supplied into the treatment chamber (6), and gas within the treatment chamber (6) is continuously discharged. Therefore, the concentration of ammonia remaining in the treatment chamber (6) gradually decreases during the concentration measurement phase. Additionally, valves (113) and (213) are closed during the concentration measurement phase.

[0133] After 60 seconds have elapsed since the timer (38) started the timer, the process proceeds from step S26 to step S28, and at that point, the control unit (3) determines whether the concentration of ammonia remaining in the processing chamber (6), measured by the gas detector (251), is below the allowable value. If the concentration of ammonia remaining in the processing chamber (6) is below the allowable value, the process proceeds from step S28 to step S29, and the control unit (3) permits the opening of the gate valve (185).

[0134] FIG. 16 is a drawing showing an example of a GUI displayed on a display unit (33) when the opening of the gate valve (185) is permitted. Unlike FIG. 14, an “Open” button (501) is displayed selectably for the gate valve (185) (the grayout display is disabled). Also, the concentration of ammonia measured by the gas detector (251) is displayed. When an operator presses the “Open” button (501) for the gate valve (185), the gate valve (185) opens, making it possible to remove the semiconductor wafer (W) that has stopped processing from the processing chamber (6). Since the concentration of ammonia remaining in the processing chamber (6) is below a safe allowable value, there is no risk of dangerous ammonia leaking from the processing chamber (6) to the return chamber (170) even when the gate valve (185) is opened.

[0135] Meanwhile, when the concentration of ammonia remaining in the processing chamber (6) measured by the gas detector (251) is greater than the allowable value, the process proceeds from step S28 to step S30, and the control unit (3) does not permit the opening of the gate valve (185). In this case, the display unit (33) continues to display the display of FIG. 14. Therefore, the operator cannot open the gate valve (185), and the leakage of ammonia from the processing chamber (6) to the return chamber (170) is prevented, thereby ensuring safety. In this case, the operator may press the “Residual check” button (503) again to repeat the residual gas check until the concentration of ammonia remaining in the processing chamber (6) becomes less than or equal to the allowable value.

[0136] In this embodiment, a processing chamber (6) for performing heat treatment of a semiconductor wafer (W) and a return chamber (170) for accommodating a return robot (150) are connected via a gate valve (185) and an O-ring (186). If the O-ring (186) is damaged while the inside of the processing chamber (6) is under reduced pressure during heat treatment of the semiconductor wafer (W), there is a risk that the inside of the return chamber (170) will rapidly depressurize. Therefore, in this embodiment, while heat treatment of the semiconductor wafer (W) is being performed in the processing chamber (6), changes in the pressure of the gas inside the return chamber (170) are monitored. Then, if the pressure inside the return chamber (170) falls below a second threshold value (Th2), it is treated as a pressure abnormality of the return path, and if it falls below a first threshold value (Th1), the heat treatment is stopped and pressure adjustment of the processing chamber (6) and the return chamber (170) is performed to restore the internal pressure of both to atmospheric pressure. In short, if the possibility that the O-ring (186) is damaged is detected, the pressure inside the processing chamber (6) and the return chamber (170) is immediately restored to atmospheric pressure. By doing so, the pressure difference between the processing chamber (6) and the return chamber (170) is reduced, thereby preventing the inside of the return chamber (170) from being severely depressurized, which can prevent damage to the quartz window (173). In other words, problems caused by damage to the O-ring (186) connecting the processing chamber (6) and the return chamber (170) can be mitigated.

[0137] In addition, in this embodiment, before opening the gate valve (185) to recover the semiconductor wafer (W) whose processing has been stopped, a check of the concentration of reactive gas remaining in the processing chamber (6) is performed. As a result of measuring the concentration for a predetermined time, if the concentration of reactive gas remaining in the processing chamber (6) is below an allowable value, the opening of the gate valve (185) is permitted. In addition, if the check of the concentration of the remaining reactive gas is not performed, the opening of the gate valve (185) is prohibited. Therefore, dangerous reactive gas is prevented from leaking from the processing chamber (6) to the return chamber (170).

[0138] Although embodiments of the present invention have been described above, various modifications other than those described above are possible without departing from the spirit of the invention. For example, in the above embodiment, when the pressure inside the return chamber (170) becomes less than or equal to the first threshold value (Th1), pressure adjustment between the processing chamber (6) and the return chamber (170) was performed, but it is not necessary to perform pressure adjustment between both; at least, the pressure inside the processing chamber (6) should be restored to atmospheric pressure. At least, if the pressure inside the processing chamber (6) is restored to atmospheric pressure, the pressure difference between the processing chamber (6) and the return chamber (170) is reduced, and problems caused by the breakage of the O-ring (186) can be mitigated. Also, when restoring the pressure inside the processing chamber (6) to atmospheric pressure, at least the vacuum pump (214) should be stopped and an inert gas supplied into the processing chamber (6).

[0139] In addition, in the above embodiment, the concentration of reactive gas remaining in the processing chamber (6) was checked in step S18, but in addition to this, the concentration of reactive gas remaining in the return chamber (170) may also be checked. Normally, when heat-processing a semiconductor wafer (W), the processing chamber (6) is at a lower pressure than the return chamber (170), so reactive gas such as ammonia does not flow from the processing chamber (6) to the return chamber (170), but when the O-ring (186) is damaged, reactive gas may leak into the return chamber (170). When checking the residual gas in the return chamber (170), the valve (393) is opened in the same way as the residual gas check for the processing chamber (6) (Fig. 13), and the gas detector (391) measures the concentration of reactive gas by sampling from the gas exhaust pipe (371) for 60 seconds. Then, the control unit (3) determines whether the concentration of the reactive gas remaining in the return chamber (170) is below the allowable value.

[0140] Additionally, the residual gas check in the processing chamber (6) may be performed when it is necessary to open the gate valve (185), such as when the vacuum pump (214) fails or when the semiconductor wafer (W) is broken during flash light irradiation.

[0141] In addition, in the layout of the substrate processing device (100) shown in FIG. 1, a chamber of a scratch detection unit that detects scratches on the back surface of a semiconductor wafer (W) may be connected to the side ((-Y) side) of the indexer unit (101) opposite to the alignment unit (230).

[0142] In addition, in the above embodiment, ammonia was used as a reactive gas during the heat treatment of the semiconductor wafer (W), but it is not limited thereto. Examples of reactive gases that are dangerous if leaked into the return chamber (170) include ozone, for instance.

[0143] In addition, in the above embodiment, 30 flash lamps (FL) were provided in the flash lamp house (5), but this is not limited thereto, and the number of flash lamps (FL) can be any number. Also, the flash lamps (FL) are not limited to xenon flash lamps and may be krypton flash lamps. Also, the number of halogen lamps (HL) provided in the halogen lamp house (4) is not limited to 40 and can be any number.

[0144] In addition, in the above embodiment, preheating of the semiconductor wafer (W) was performed using a filament type halogen lamp (HL) as a continuous lighting lamp that emits light continuously for more than 1 second, but it is not limited thereto, and preheating may be performed using a discharge type arc lamp (e.g., xenon arc lamp) or an LED lamp as a continuous lighting lamp instead of a halogen lamp (HL). Explanation of the symbols

[0145] 3: Control unit 4: Halogen Lamp House 5: Flash Lamp House 6: Processing chamber 7: Maintenance Department 10: Lee Jae Ki-gu 20: Radiation thermometer 38: Timer 65: Heat treatment space 74: Susceptor 84, 350: Gas supply unit 89, 370: Exhaust section 95, 380: Pressure gauge 111, 113, 211, 213, 253, 352, 393: Supply valve 100: Substrate processing device 101: Western Index 110: Load port 120: Capital Robot 131: 1st Cool Chamber 141: Second Cool Chamber 150: Return robot 160: Heat Treatment Section 170: Return chamber 185: Gate valve 186: O-ring 214: Vacuum pump 251, 391: Gas detector 372: Pressure regulating valve C: Carrier FL: Flash lamp HL: Halogen lamp W: Semiconductor wafer

Claims

Claim 1 A substrate processing method for heating a substrate by irradiating light onto the substrate, comprising: a receiving process of introducing a substrate into a processing chamber connected to a receiving chamber containing a receiving robot via a gate valve and an O-ring; a processing process of performing a heat treatment by irradiating light onto the substrate while forming an atmosphere of a predetermined reactive gas within the processing chamber containing the substrate and reducing the pressure within the processing chamber to less than atmospheric pressure; a detection process of detecting whether the pressure within the receiving chamber has become below a first threshold value of less than atmospheric pressure during the execution of the processing process; and a pressure recovery process of stopping an exhaust pump that reduces the pressure within the processing chamber and supplying an inert gas into the processing chamber to restore the pressure within the processing chamber to atmospheric pressure when it is detected that the pressure within the receiving chamber has become below the first threshold value. Claim 2 A substrate processing method according to claim 1, wherein when it is detected that the pressure inside the return chamber has become below the first threshold value, an inert gas is additionally supplied into the return chamber to restore the pressure inside the return chamber to atmospheric pressure. Claim 3 A substrate processing method according to claim 1, wherein when it is detected in the detection process that the pressure inside the return chamber has become lower than or equal to a second threshold value which is higher than the first threshold value, the subsequent introduction of a substrate into the processing chamber is stopped while continuing the processing process, and when it is detected in the detection process that the pressure inside the return chamber has become lower than or equal to the first threshold value, the pressure reduction process is executed. Claim 4 A substrate processing method according to claim 1, further comprising a first concentration measuring process for measuring the concentration of the reactive gas remaining in the processing chamber after the processing chamber is pressured to atmospheric pressure in the pressure process, and allowing the opening of the gate valve if the concentration of the reactive gas in the processing chamber is less than or equal to a predetermined value. Claim 5 A substrate processing method according to claim 4, wherein, after the processing chamber is pressured to atmospheric pressure in the pressure process, the opening of the gate valve is prohibited if the first concentration measurement process is not performed. Claim 6 A substrate processing method according to claim 4, further comprising a second concentration measuring process for measuring the concentration of the reactive gas in the return chamber after the processing chamber is pressured to atmospheric pressure in the pressure process. Claim 7 A substrate processing device for heating a substrate by irradiating light onto the substrate, comprising: a return chamber for accommodating a return robot; a processing chamber connected to the return chamber through a gate valve and an O-ring; a first gas supply unit for supplying a predetermined reactive gas or inert gas to the processing chamber; an exhaust unit including an exhaust pump for exhausting gas from the processing chamber to reduce the pressure inside the processing chamber; a light irradiation unit for irradiating light onto a substrate accommodated in the processing chamber; a first pressure gauge for measuring pressure inside the processing chamber; a second pressure gauge for measuring pressure inside the return chamber; and a control unit for controlling the first gas supply unit and the exhaust unit. During the execution of a heating process in which light is irradiated onto the substrate while forming an atmosphere of the reactive gas inside the processing chamber that accommodates the substrate and reduces the pressure inside the processing chamber to less than atmospheric pressure, when it is detected that the pressure inside the return chamber measured by the second pressure gauge has fallen below a first threshold value of less than atmospheric pressure, the control unit stops the exhaust pump and supplies an inert gas into the processing chamber to the processing chamber A substrate processing device that controls the first gas supply unit to apply internal pressure to atmospheric pressure. Claim 8 A substrate processing apparatus according to claim 7, further comprising a second gas supply unit for supplying an inert gas to the return chamber, wherein when it is detected that the pressure inside the return chamber has become below the first threshold value, the control unit controls the second gas supply unit to supply an inert gas to the return chamber so as to restore the pressure inside the return chamber to atmospheric pressure. Claim 9 A substrate processing apparatus according to claim 7, wherein when it is detected that the pressure inside the return chamber measured by the second pressure gauge has become lower than or equal to a second threshold value that is higher than the first threshold value, the subsequent introduction of a substrate into the processing chamber is stopped while continuing the heat treatment. Claim 10 A substrate processing apparatus according to claim 7, further comprising a first gas detection unit for measuring the concentration of the reactive gas in the processing chamber, and allowing the opening of the gate valve if the concentration of the reactive gas remaining in the processing chamber is less than or equal to a predetermined value after the processing chamber is pressurized to atmospheric pressure. Claim 11 A substrate processing apparatus according to claim 10, wherein, after the processing chamber is pressurized to atmospheric pressure, the opening of the gate valve is prohibited if the concentration of the reactive gas in the processing chamber by the first gas detection unit is not measured. Claim 12 A substrate processing apparatus according to claim 10, further comprising a second gas detection unit for measuring the concentration of the reactive gas in the return chamber, and measuring the concentration of the reactive gas in the return chamber by the second gas detection unit after the processing chamber is pressurized to atmospheric pressure.

Images