Substrate mounting method and substrate mounting mechanism

Abstract

To provide a substrate placement method and a substrate placement mechanism with which, when placing a substrate on the placement face of a placement table, it is possible to place the substrate at a desired position even when the substrate is locked at an undesired position due to lateral displacement having occurred to the substrate, and a substrate processing device.SOLUTION: A substrate placement method for placing a substrate in position includes: a step of locating a lifting pin which is retractably provided to a placement face at a substrate delivery position protruding upward of the placement face and delivering the substrate to the lifting pin; then, a step of lowering the lifting pin, with the substrate placed thereon, to a substrate placement position downward of the placement face; and then, a step of elevating the lifting pin a minute distance and subsequently returning to the substrate placement position. When an edge of the substrate is locked to a tapered face when lowering the lifting pin from the substrate delivery position to the substrate placement position, the clocking of the edge to the tapered face is unlocked and the substrate is guided to the placement face by the step of elevating the lifting pin a minute distance and subsequently returning to the substrate placement position.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a substrate mounting method and a substrate mounting mechanism. [Background technology]

[0002] For example, when processing a substrate such as a semiconductor wafer, the substrate is placed on a mounting table having a horizontal mounting surface. Patent Document 1 describes a mounting table having a mounting surface for the substrate at the bottom of a recess and a tapered surface on the outer periphery of the mounting surface that guides the substrate onto the mounting surface, where the substrate is placed with its underside non-parallel to the mounting surface to prevent lateral displacement of the substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-50904 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a substrate mounting method and a substrate mounting mechanism that can mount a substrate at a desired position even when the substrate shifts laterally and becomes locked in an undesired position when the substrate is placed on the mounting surface of a mounting table. [Means for solving the problem]

[0005] A substrate mounting method according to an aspect of the present disclosure includes: was established , a mounting surface on which a substrate is mounted 、 and 、 the outer periphery of the mounting surface From above the placement surface to the placement surface Guide the board The tapered portion is formed in a circular shape with a constant taper angle. Tapered surface 、 A mounting table having In the mounting surface Based onA substrate mounting method for mounting a plate, comprising the steps of: positioning lift pins, which are provided so as to be protrudable and retractable relative to the mounting surface, at a substrate transfer position protruding above the mounting surface; and transferring the substrate onto the lift pins; subsequently, lowering the lift pins with the substrate mounted thereon to a substrate mounting position below the mounting surface; and subsequently, raising the lift pins by a small distance and subsequently The aforementioned and a step of returning the lift pins to the substrate placement position, to make When the edge of the substrate is engaged with the tapered surface, the lift pins are raised by a small distance and then The aforementioned By returning the substrate to the substrate placement position, the edge is engaged with the tapered surface. but Resolution and, in the process of returning the lift pins to the substrate mounting position, The substrate is guided by the tapered surface The mounting surface Can be . [Effects of the Invention]

[0006] According to the present disclosure, when placing a substrate on the placement surface of a placement table, even if the substrate shifts laterally and becomes locked in an undesired position, the substrate can be placed in the desired position. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a perspective view showing an example of a substrate mounting mechanism for performing a substrate mounting method according to an embodiment. [Figure 2] FIG. 2 is a plan view showing an example of a substrate mounting mechanism for performing a substrate mounting method according to an embodiment. [Figure 3] 1 is a cross-sectional view showing an example of a substrate mounting mechanism for performing a substrate mounting method according to an embodiment. [Figure 4] 1 is a flowchart illustrating an embodiment of a substrate mounting method. [Figure 5] 1A to 1C are schematic diagrams illustrating an embodiment of a substrate mounting method. [Figure 6] 10A and 10B are diagrams for explaining lateral displacement of a wafer on lift pins. [Figure 7]FIG. 10 is a schematic diagram showing a state in which the edge of the wafer is locked on a tapered surface. [Figure 8] 10A and 10B are diagrams for explaining chipping that occurs when a wafer is electrostatically attracted with its edge locked on a tapered surface. [Figure 9] 10A and 10B are diagrams showing a mechanism for releasing the engagement of the wafer edge with the tapered surface by a process of lifting the lift pins by a small distance and then returning them to the wafer placement position. [Figure 10] FIG. 10 is a diagram showing the state of the substrate when preheating is performed. [Figure 11] 1 is a cross-sectional view showing a substrate processing apparatus to which a substrate mounting mechanism is applied. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described with reference to the accompanying drawings.

[0009] <Substrate placement mechanism> First, an example of a substrate mounting mechanism for carrying out a substrate mounting method according to an embodiment will be described. Fig. 1 is a perspective view of the substrate mounting mechanism, Fig. 2 is a plan view thereof, and Fig. 3 is a cross-sectional view thereof.

[0010] The substrate mounting mechanism 1 mounts a substrate in a chamber maintained under vacuum in a substrate processing apparatus for processing the substrate. An example of the substrate is a semiconductor wafer (hereinafter simply referred to as a wafer), and the following description will be given of a case where a wafer is used as the substrate. The substrate processing apparatus is not particularly limited, but examples thereof include a film formation apparatus that forms a film by CVD or ALD. The CVD or ALD may be plasma CVD or plasma ALD.

[0011] The substrate mounting mechanism 1 has a mounting table 2 on which a wafer W is mounted, and a support member 3 attached to the center of the rear surface of the mounting table 2 so as to extend downward.

[0012] The mounting table 2 is made of a dielectric material, such as a ceramic material such as aluminum nitride (AlN). An attraction electrode 11 for attracting the wafer W is embedded inside the mounting table 2 near its surface, forming an electrostatic chuck. The attraction electrode 11 is made of, for example, Mo and has a mesh shape. A DC power supply 14 is connected to the attraction electrode 11 via a power supply line 13, and the wafer W is electrostatically attracted by applying a DC voltage to the attraction electrode 11. The DC power supply 14 can be turned on and off by a switch (not shown). The attraction electrode 11 also functions as a ground electrode for plasma.

[0013] 3, a heater 12 may be embedded below the chucking electrode 11 inside the mounting table 2. For example, during a film formation process using CVD or ALD, the wafer W is heated by the heater 12. A heater power supply 16 is connected to the heater 12 via a power supply line 15, and the output of the heater 12 is controlled based on the detection value of a temperature sensor (not shown) such as a thermocouple, thereby controlling the temperature of the mounting table 2.

[0014] On the surface of the mounting table 2, a ring-shaped mounting surface 21 is formed at a position corresponding to the outer periphery of the wafer W, on which the wafer W is mounted.

[0015] An attraction surface 22 is formed on the inner side of the mounting surface 21 at a position approximately 20 to 70 μm lower than the mounting surface 21. The attraction surface 22 is the surface to which the wafer W is attracted when the electrostatic chuck is turned on, and is, for example, an embossed surface. When the wafer W is attracted to the attraction surface 22 by the electrostatic chuck, the wafer W is in close contact with the mounting surface 21, which more effectively prevents the formation of a deposition film caused by reactive gases moving around to the back side of the wafer W when the substrate is processed by CVD or ALD. In particular, when a conductive film is formed by plasma CVD or plasma ALD, leakage current and arcing caused by the formation of a conductive deposition film can be suppressed.

[0016] A gas inlet 24 is formed on the adsorption surface 22, and a backside gas supplied from the gas supply source 18 via the gas supply path 17 is supplied from the gas inlet 24 into the space 23. The gas supply source 18, the gas supply path 17, and the gas inlet 24 constitute a backside gas supply mechanism. A gas with high thermal conductivity, such as helium (He) gas, is used as the backside gas, and heat from the mounting table 2 is transferred to the wafer W via the backside gas.

[0017] A guide portion 26 for guiding the wafer W is formed in a circular shape on the surface of the mounting table 2, outside the mounting surface 21. The inner surface of the guide portion 26 is a tapered surface 26a that guides the wafer W to the mounting surface 21 when the wafer W shifts laterally. The taper angle α of the tapered surface 26a shown in FIG. 3 is preferably 50 to 70°, and is, for example, 60°. Within this range, the function of guiding the edge of the wafer W can be effectively achieved.

[0018] The inside of guide portion 26 is a recessed portion 27, and mounting surface 21 is located at the bottom of recessed portion 27, so that wafer W mounted on mounting surface 21 is accommodated in recessed portion 27. The height of recessed portion 27, i.e., the height of the upper surface of guide portion 26 from mounting surface 21, is, for example, 0.5 to 1 mm.

[0019] A circular groove 25 is formed between the mounting surface 21 and the guide portion 26. The groove 25 is for accumulating a gas-deposited film when the processing by the processing apparatus uses gas. In particular, when the processing by the processing apparatus is to form a conductive film, accumulating the deposited film in the groove 25 prevents the conductive deposited film from wrapping around the mounting surface of the wafer W and impairing the electrostatic chuck function.

[0020] Three lift pin insertion holes 28 (only two are shown in FIG. 3 ) that penetrate vertically are formed in a portion of the mounting table 2 that corresponds to the mounting surface 21, and a lift pin 29 is inserted into each lift pin insertion hole 28 so as to be able to protrude and retract into the mounting surface 21. These lift pins 29 are supported on a support plate 30. The lift pins 29 are raised and lowered via the support plate 30 by a drive mechanism 31 such as an air cylinder. The lift pins 29 move between a wafer transfer position where they protrude from the mounting surface 21 and a wafer mounting position below the mounting surface 21, and a wafer W is transferred onto the lift pins 29 at the wafer transfer position, and the wafer W is mounted on the mounting surface 21 at the wafer mounting position.

[0021] The lifting and lowering operation of the lift pins 29 by the drive mechanism 31 is controlled by the lift control unit 40, which controls the operation of placing the wafer W placed on the lift pins 29 onto the placement surface 21. Note that other controls, such as voltage application to the heater 12 and the chucking electrode 11 of the substrate placement mechanism 1, are performed by a higher-level control unit (not shown in FIGS. 1 to 3; see the control unit 160 described below).

[0022] The electrostatic chuck has a function of correcting warpage of the wafer W, which is a substrate. From the viewpoint of effectively correcting warpage of the wafer W, it is preferable to attract the wafer W by the Johnson-Rahbek force by supplying power to the attraction electrode 11. The attraction of the wafer W by the Johnson-Rahbek force is performed when the volume resistivity of the dielectric at the film formation temperature is 1×10 9 ~1×10 12 This is done by lowering the resistivity to around Ω·cm to allow for the movement of charges. This allows for a larger amount of charge to be stored, resulting in an attraction force greater than Coulomb force. By using AlN as the dielectric, it is possible to obtain a volume resistivity within the above range, allowing the Johnsen-Rahbek force to be exerted effectively.

[0023] When using an electrostatic chuck, it is effective to set the temperature of the surface of the mounting table 2 by the heater 12, i.e., the temperature of the wafer W, at 200°C or higher. If the heating temperature is 200°C or higher, the wafer W, which is the substrate, is likely to warp significantly, making the electrostatic chuck function more important. A temperature of 400°C or higher, or even 400 to 700°C, can provide even greater effects.

[0024] It should be noted that the electrostatic chuck is not necessarily provided. If an electrostatic chuck is not provided, the attracting electrode 11, attracting surface 22, and space 23 are not required, and the entire surface of the wafer W can be placed on the placement surface 21.

[0025] <Substrate placement method> Next, one embodiment of a substrate mounting method for mounting a substrate, i.e., a wafer W, on the mounting table 2 of the substrate mounting mechanism 1 configured as described above will be described with reference to the flowchart of Fig. 4 and the schematic diagram of Fig. 5. This substrate mounting method is performed by controlling the lift pins 29 using the lift control unit 40.

[0026] First, as shown in FIG. 5(a), the lift pins 29 are positioned at a wafer transfer position protruding above the mounting surface 21, and the wafer W that has been loaded into a vacuum chamber is transferred onto the lift pins 29 (step 1).

[0027] 5(b), the lift pins 29 are lowered to a wafer placement position below the placement surface 21 (step 2). As a result, the wafer W is normally placed on the placement surface 21.

[0028] Next, as shown in FIG. 5(c), the lift pins 29 are raised by a small distance and then returned to the wafer placement position (step 3).

[0029] The reasons for performing step 3 will be explained in detail below. During the operation of lowering the lift pins 29 carrying the wafer W from the wafer transfer position to the wafer placement position, as shown in FIG. 6, the wafer W may slip on the lift pins 29, causing a lateral displacement and causing the edge of the wafer W to come into contact with the tapered surface 26a of the guide portion 26. This is likely to occur in film formation processes using CVD or ALD, which are performed at relatively high pressures. The tapered surface 26a is designed to guide the wafer W when the edge of the wafer W comes into contact with the tapered surface 26a. Therefore, normally, even if the edge of the wafer W comes into contact with the tapered surface 26a, the weight of the wafer W causes the edge of the wafer W to slide along the tapered surface 26a, and the wafer W is placed on the placement surface.

[0030] However, there are cases where the edge of the wafer W remains locked on the tapered surface 26a, and the wafer W is not accurately placed on the placement surface 21. This phenomenon is thought to occur because, as shown in Fig. 7, the edge of the wafer W rises up and becomes slightly bitten into the tapered surface 26a, resulting in a local increase in frictional resistance.

[0031] When such a phenomenon occurs, various inconveniences occur. For example, when an electrostatic chuck is used, as shown in Fig. 8, when the wafer W is electrostatically attracted, stress is applied locally to the portion of the edge of the wafer W that is engaged with the tapered surface 26a, which may cause chipping. Even when an electrostatic chuck is not used, a space is created between the back surface of the wafer W and the mounting surface 21 due to the edge of the wafer W being engaged with the tapered surface 26a, which makes it easier for a deposition film to form on the back surface of the wafer W.

[0032] This phenomenon occurs in about one out of every 1,000 wafers, but even this frequency can be problematic in the semiconductor manufacturing process.

[0033] Therefore, in this embodiment, after performing step 2 in which the lift pins 29 are lowered to the wafer placement position, step 3 is performed in which the lift pins 29 are raised a small distance and then returned to the wafer placement position, thereby releasing the engagement of the wafer edge on the tapered surface 26a. That is, in step 3, by temporarily raising the lift pins 29 a small distance, the wafer W that had been engaged on the tapered surface 26a is lifted, as shown in FIG. 9(a), and the edge of the wafer W is released from the tapered surface 26a, thereby resetting the large localized frictional resistance. Then, when the lift pins 29 are lowered again to the wafer placement position, the edge of the wafer W slides on the tapered surface 26a, and the wafer W is placed on the placement surface 21, as shown in FIG. 9(b).

[0034] When an electrostatic chuck is used, after the wafer W is placed on the mounting surface 21 as described above, a DC voltage is applied to the attracting electrode 11 of the electrostatic chuck to attract the wafer W. As described above, in step 3, the edge of the wafer W is released from the tapered surface 26, and the wafer W can be placed on the mounting surface 21. Therefore, when the wafer W is electrostatically attracted in this manner, local chipping of the wafer edge can be prevented.

[0035] Furthermore, even when an electrostatic chuck is not used, it is possible to prevent a space from being generated between the rear surface of the wafer W and the mounting surface 21, and prevent a deposition film from being formed on the rear surface of the wafer W.

[0036] In step 3, the lifting distance (very small distance) of the lifting pins 29, i.e., the stroke for lifting the wafer W, must be a value that can release the edge of the wafer W from being caught (bitten) on the tapered surface 26a. From this perspective, the lifting distance of the lifting pins 29 is preferably 1 mm or more. Furthermore, if the lifting distance of the lifting pins 29 is too large, it will affect the takt time. Therefore, in order to avoid affecting the takt time, the lifting distance of the lifting pins 29 is preferably 3 mm or less. With this level of lifting distance, the time required for the lifting pins to be lowered again after being raised is approximately 1 second or less, which has almost no effect on the takt time. From the above, it is preferable that the lifting distance of the lifting pins 29 in step 3 be 1 to 3 mm.

[0037] This step is necessary only for wafers whose edges are locked on the tapered surface 26a, but it is preferable to perform this step for all wafers W. This makes it possible to easily perform the step, since it is not necessary to provide a means for detecting whether the edge of the wafer W is locked or to change the step depending on the wafer.

[0038] 10, the lifting pins 29 may be stopped midway, and the wafer W may be brought close to the mounting surface 21, and an inert gas such as Ar gas may be supplied as a thermally conductive gas into the chamber to preheat the wafer W. At this time, the distance between the wafer W and the mounting surface 21 is set to 0.5 to 1 mm, for example, 1 mm.

[0039] The pressure inside the chamber when the wafer W is placed on the placement surface 21 is preferably 13.3 Pa (0.1 Torr) or less. When placing the wafer W on the placement surface 21, the lift pins 29 are lowered with the wafer W placed on them, but it has been confirmed that if the pressure inside the chamber is higher than 13.3 Pa (0.1 Torr) immediately before placement, lateral displacement of the wafer W is more likely to occur when it is placed. In other words, by setting the pressure inside the chamber when placing the wafer W on the placement surface 21 to 13.3 Pa (0.1 Torr) or less, the effect of suppressing lateral displacement of the wafer W itself can be obtained.

[0040] The chamber may be set to such a low pressure state from the beginning of the wafer mounting sequence, but if preheating is performed, the chamber may be set to a low pressure state after preheating, with the lift pins 29 left as they are, with the wafer W in close proximity to the mounting surface 21. Also, even if preheating is not performed, the chamber may be set to a low pressure state after the lift pins 29 are stopped midway.

[0041] <Substrate processing equipment> Next, a substrate processing apparatus to which the above-described substrate mounting mechanism is applied will be described. FIG. 11 is a cross-sectional view showing a substrate processing apparatus.

[0042] The substrate processing apparatus 100 is configured as a film forming apparatus that forms a tungsten (W) film by CVD.

[0043] This substrate processing apparatus 100 has a generally cylindrical metal chamber 101. The chamber 101 has an exhaust chamber 151 that protrudes downward to cover a circular hole 150 formed in the center of a bottom wall 101b of the main body. An exhaust pipe 152 is connected to the side of the exhaust chamber 151, and this exhaust pipe 152 is provided with an exhaust device 153 that has a pressure control valve and a vacuum pump. This exhaust device 153 makes it possible to exhaust the air inside the chamber 101 and to control the pressure inside the chamber 101 to a predetermined reduced pressure state.

[0044] The side wall of the chamber 101 is provided with a loading / unloading port 157 for loading / unloading the wafer W between the chamber 101 and a wafer transfer chamber (not shown) provided adjacent to the chamber 101, and a gate valve 158 for opening / closing the loading / unloading port 157.

[0045] The substrate mounting mechanism 1 having the above-described configuration is provided inside the chamber 101. The support member 3 of the substrate mounting mechanism 1 is attached to the bottom wall of the exhaust chamber 151 via an insulating member 4. In addition, the drive mechanism 31 that raises and lowers the lift pins 29 is attached to the outside of the exhaust chamber 151.

[0046] A shower head 110 is provided on the ceiling wall 101a of the chamber 101 so as to face the mounting table 2 of the substrate mounting mechanism 1. The shower head 110 functions as a gas inlet. The shower head 110 has a base member 111 and a shower plate 112, and the outer periphery of the shower plate 112 is screwed to the base member 111. A gas diffusion space 114 is formed between the base member 111 and the shower plate 112. The base member 111 is supported by the ceiling wall 101a. The shower plate 112 has a gas discharge surface 118 facing the mounting table 2, and a plurality of gas discharge holes 115 are formed in the shower plate 112. A gas inlet hole 116 is formed near the center of the base member 111. A gas piping of a gas supply mechanism 120 (described later) is connected to the gas inlet hole 116, and processing gas supplied from the gas supply mechanism 120 is introduced into the chamber 101 in a shower-like manner via the shower head 110.

[0047] A heater 147 for heating the shower head 110 is provided on the base member 111 of the shower head 110. The heater 147 is powered by a heater power supply (not shown) and heats the shower head 110 to a desired temperature. A heat insulating member 149 is provided in a recess formed in the upper part of the base member 111.

[0048] The gas supply mechanism 120 has a ClF3 gas supply source 121, an N2 gas supply source 122, a WF6 gas supply source 123, an Ar gas supply source 124, a SiH4 gas supply source 125, and an H2 gas supply source 126. ClF3 gas is used as a cleaning gas. WF6 gas is used as a W raw material gas. SiH4 gas and H2 gas are used as reducing gases. N2 gas and Ar gas are used as a carrier gas and a purge gas.

[0049] A gas line 127 is connected to the ClF3 gas supply source 121. A gas line 128 is connected to the N2 gas supply source 122. A gas line 129 is connected to the WF6 gas supply source 123, and a branch line 130 branches off from the gas line 129 midway. This branch line 130 is used in the nucleation process described below, and the flow rate is strictly controlled. A gas line 131 is connected to the Ar gas supply source 124. The gas line 129 and the branch line 130 merge into this gas line 130. A gas line 132 is connected to the SiH4 gas supply source 125. A gas line 133 is connected to the H2 gas supply source 126. The gas lines 127, 128, 131, 132, and 133 are connected to a common gas line 139, which is connected to the gas inlet hole 116. The gas passes through gas introduction holes 116 and reaches gas diffusion space 114 , and is discharged in a shower-like manner toward wafer W in chamber 101 through gas discharge holes 115 of shower plate 112 .

[0050] A mass flow controller 137 as a flow rate controller and two opening and closing valves 136 before and after the mass flow controller 137 are provided on the gas lines 127, 128, 129, 130, 131, 132, and 133. The flow rate controller is not limited to the mass flow controller 137.

[0051] The substrate processing apparatus 100 includes a control unit 160 that controls the valves 136, the mass flow controller 137, the matching box 140, the high-frequency power supply 141, the elevation control unit 40 for the substrate mounting mechanism 1, the DC power supply 14, the heater power supply 16, etc. The control unit 160 includes a main control unit having a CPU (computer) that controls the above-mentioned components, an input device, an output device, a display device, and a storage device. A storage medium storing a program for controlling the processing executed in the substrate processing apparatus 100, i.e., a processing recipe, is set in the storage device, and the main control unit calls up a predetermined processing recipe stored in the storage medium and controls the substrate processing apparatus 100 to perform a predetermined processing based on the processing recipe.

[0052] Next, a W film formation process performed using the substrate processing apparatus 100 described above will be described.

[0053] Here, a typical example is shown in which a W thin film is formed on a TiN thin film that has been formed as a barrier layer on a wafer W in advance.

[0054] First, before the wafer W is loaded into the chamber 101, a pre-coating process is performed inside the chamber 101. The inside of the chamber 101 is heated preferably to 350 to 450°C, and processes similar to the initiation process, nucleation process, and W film formation process described below are sequentially performed under the same conditions to form a pre-coating film on the inner wall of the chamber 101, the surface of the mounting table 2, the shower head 110, etc.

[0055] After the pre-coating process is completed, the chamber 101 is purged with Ar gas and N2 gas. Next, after adjusting the pressure inside the chamber 101, the gate valve 158 is opened and the wafer W is loaded into the chamber 101 from a vacuum transfer chamber (not shown) via the transfer port 157 by a transfer mechanism (not shown). The wafer W is then placed on the mounting surface 21 of the mounting table 2, which is maintained at a predetermined temperature by the heater 12.

[0056] When placing the wafer W on the mounting surface 21 of the mounting table 2, as described above, the lift pins 29 are positioned at the wafer transfer position protruding from the mounting surface 21, and the wafer W is transferred onto the lift pins 29.

[0057] Next, the lift pins 29 are stopped midway, and Ar gas is supplied as a thermal conduction gas into the chamber with the wafer W in close proximity to the mounting surface 21 to preheat the wafer W. Next, with the wafer W remaining in the same position, the chamber 101 is evacuated to reduce the pressure therein to 13.3 Pa (0.1 Torr) or less. This prevents the wafer W from shifting laterally on the lift pins 29. The lift pins 29 are then lowered to a wafer mounting position below the mounting surface 21. Next, the lift pins 29 are raised a small distance and returned to the wafer mounting position. As described above, by performing this step, even if the wafer W shifts laterally on the lift pins 29 and the edge of the shifted wafer W becomes engaged with the tapered surface 26 a, the engagement of the edge of the wafer W is reset, and the wafer W engaged with the tapered surface 26 a can be placed on the mounting surface 21.

[0058] First, an initiation process is performed on the wafer W placed on the mounting table 2 to suppress abnormal grain growth in the W film to be formed thereafter and to obtain a good surface condition. The initiation process is performed by supplying SiH4 gas and H2 gas into the chamber 101 via the shower head 110 to form SiH on the TiN film. x (e.g. x=1~3) is adsorbed.

[0059] After this initiation process, a nucleation process is carried out by supplying WF6 gas, Ar gas, H2 gas, and N2 gas into the chamber 101. During this nucleation process, the mass flow controller 137 of the branch line 130 branching off from the middle of the gas line 129 is designed to be able to more precisely control the flow rate, and W nuclei are generated by strictly controlling the flow rate of the WF6 gas at a smaller amount than during the film formation process.

[0060] Next, while Ar gas, H2 gas, and N2 gas are still being supplied, the branch line 130 is switched to the main gas line 129, and WF6 gas is flowed at a flow rate greater than that during nucleation to perform the film formation process of the W film.

[0061] In these nucleation treatments and film formation treatments, the heating temperature is preferably 380 to 500°C.

[0062] After the film formation process is performed for a predetermined time, the valve of the gas line 129 is closed, the supply of WF6 gas and the like from the WF6 gas supply source 123 is stopped, and the film formation process is completed.

[0063] Thereafter, the chamber 101 is purged with Ar gas, and then the wafer W is pushed up by the lift pins 16 and carried out of the chamber 101 by the transfer arm.

[0064] After the above steps are repeated for a given number of wafers W, the interior of the chamber is cleaned by supplying ClF3 gas into the chamber 11. After cleaning, a pre-coating process is performed again, and the above-described process is repeated.

[0065] In the W film formation process on the wafer W by the substrate processing apparatus 100 as described above, when the wafer W is placed on the mounting table 2, the lift pins 29 are raised by a small distance and then returned to the wafer mounting position. This makes it possible to eliminate any jamming of the edge of the wafer W into the tapered surface 26a, and to prevent chipping of the edge of the wafer W due to local stress when the wafer W is electrostatically attracted to the mounting table 2 by the electrostatic chuck.

[0066] Furthermore, the W film formation process by the substrate processing apparatus 100 is performed at a high temperature of 380 to 500°C, which can cause warpage of the wafer W. However, by electrostatically attracting the wafer W using an electrostatic chuck, warpage of the wafer W can be made less likely to occur. This can eliminate problems caused by warpage of the wafer W, such as deterioration of processing uniformity and adhesion of deposits between the wafer W and the mounting table 2.

[0067] <Other applications> Although the embodiments have been described above, the disclosed embodiments should be considered to be illustrative and not restrictive in all respects. The above embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0068] For example, in the above embodiment, the substrate mounting mechanism for carrying out the substrate mounting method has been exemplified as one having an electrostatic chuck, but it may not have an electrostatic chuck.

[0069] Furthermore, although a film-forming apparatus that forms a W film by CVD has been exemplified as a substrate processing apparatus to which the substrate mounting method is applied, the present invention is not limited to this. For example, the type of film to be formed is not limited to a W film, and any type of film can be formed, and the present invention is not limited to a film-forming apparatus. Furthermore, although the above embodiment has exemplified a substrate processing apparatus that does not use plasma, a plasma processing apparatus may also be used.

[0070] Furthermore, the substrate mounting mechanism is not limited to the configuration of the above embodiment. For example, in the above embodiment, an example was shown in which the mounting table was supported by a support member as the substrate mounting mechanism, but the mounting table may be provided directly on the bottom of the chamber without providing a support member.

[0071] Furthermore, although an example has been given in which a semiconductor wafer is used as the substrate, the substrate is not limited to a wafer and may be other substrates such as an FPD substrate or a ceramic substrate. [Explanation of symbols]

[0072] 1. Substrate placement mechanism 2. Mounting table 3; Support member 11; Adsorption electrode 12;Heater 21: Placement surface 22;Adsorption surface 23; space 24: Gas inlet 25; Groove 26: Guide section 26a; Tapered surface 27;Recess 29; Lifting pin 31; Drive mechanism 40: Lift control section 100: Substrate processing apparatus 101; Chamber 110; shower head 120: Gas supply mechanism 141;High frequency power supply W: Semiconductor wafer (substrate)

Claims

1. A substrate mounting method for a mounting table provided in a chamber of a substrate processing apparatus for processing a substrate, the mounting table having a mounting surface for mounting a substrate thereon, and a tapered surface having a constant taper angle and forming an annular shape on an outer periphery of the mounting surface so as to be able to guide a substrate from above the mounting surface to the mounting surface, the method comprising: a step of positioning lift pins provided so as to be protrudable and retractable relative to the placement surface at a substrate transfer position protruding above the placement surface, and transferring the substrate onto the lift pins; Next, a step of lowering the lift pins on which the substrate is placed to a substrate placement position below the placement surface; Then, the lift pins are raised a small distance and subsequently returned to the substrate placement position; and a step of lifting the lift pins by a small distance and subsequently returning them to the substrate loading position when the edge of the substrate becomes engaged with the tapered surface when the lift pins are lowered from the substrate transfer position to the substrate loading position, thereby releasing the engagement of the edge with the tapered surface, and in the process of returning the lift pins to the substrate loading position, the substrate is guided by the tapered surface and introduced to the loading surface.

2. 2. The substrate mounting method according to claim 1, wherein the mounting table has an electrostatic chuck that electrostatically attracts the substrate, and further comprises the step of electrostatically attracting the substrate with the electrostatic chuck after the step of lifting the lift pins a small distance and subsequently returning them to the substrate mounting position.

3. 3. The substrate mounting method according to claim 2, wherein the mounting table has a heater, and the substrate is heated to 200[deg.] C. or higher by the heater on the mounting table.

4. 4. The substrate mounting method according to claim 3, further comprising the step of supplying a thermally conductive gas into the chamber to preheat the substrate while the lifting pins, on which the substrate is mounted, are stopped midway through their downward movement to the substrate mounting position, bringing the substrate close to the mounting surface.

5. 5. The substrate mounting method according to claim 4, further comprising the step of, after preheating the substrate, reducing the pressure in the chamber to 13.3 Pa or less while the substrate is in proximity to the mounting surface.

6. 3. The substrate mounting method according to claim 1, wherein the pressure in the chamber is set to 13.3 Pa or less when the substrate is mounted on the mounting surface.

7. 7. The substrate mounting method according to claim 1, wherein the minute distance is a value that allows the edge to be released from engagement with the tapered surface.

8. 8. The substrate mounting method according to claim 7, wherein the minute distance is 1 mm or more.

9. 9. The substrate mounting method according to claim 8, wherein the minute distance is 1 to 3 mm.

10. A substrate mounting mechanism for mounting a substrate in a chamber of a substrate processing apparatus, comprising: a mounting table having a mounting surface on which a substrate is placed, and a tapered surface that is annular and has a certain taper angle and is provided on the outer periphery of the mounting surface so as to be able to guide the substrate from above the mounting surface to the mounting surface; a lift pin that is provided so as to be protrudable and retractable relative to the placement surface and that moves up and down between a substrate transfer position that protrudes above the placement surface and a substrate placement position below the placement surface; a lifting control unit for controlling the lifting pins; and The lift control unit is the lifting pins are positioned at a substrate transfer position protruding above the placement surface; When the substrate is transferred onto the lift pins, the lift pins on which the substrate is placed are lowered to the substrate placement position; Next, the lift pins are raised by a small distance and then controlled to return to the substrate placement position; a substrate placing mechanism in which, if an edge of the substrate becomes engaged with the tapered surface when the lift pins are lowered from the substrate transfer position to the substrate placing position, the lift pins are controlled to be raised a small distance and subsequently returned to the substrate placing position, thereby releasing the engagement of the edge with the tapered surface, and the substrate is guided by the tapered surface and introduced to the placement surface in the process of returning the lift pins to the substrate placing position.

11. 11. The substrate mounting mechanism according to claim 10, wherein the mounting table has an electrostatic chuck that electrostatically attracts the substrate, and after the lift pins are controlled to be lifted a small distance and subsequently returned to a substrate mounting position, the substrate is electrostatically attracted by the electrostatic chuck.

12. 12. The substrate mounting mechanism according to claim 11, wherein the mounting table has a heater, and the substrate is heated to 200[deg.] C. or higher by the heater on the mounting table.

13. 13. The substrate placing mechanism according to claim 12, wherein the lifting control unit controls the lifting pins, on which the substrate is placed, to stop them midway through their descent to the substrate placing position, thereby bringing the substrate close to the placing surface, and in this state, a thermally conductive gas is supplied into the chamber to preheat the substrate.

14. 14. The substrate mounting mechanism according to claim 13, wherein after the substrate is preheated, the pressure in the chamber is set to 13.3 Pa or less with the lifting control unit bringing the substrate close to the mounting surface.

15. 15. The substrate mounting mechanism according to claim 10, wherein the minute distance is 1 mm or more.

16. 16. The substrate mounting mechanism according to claim 15, wherein the minute distance is 1 to 3 mm.

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