JP2016004834A - Vacuum processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress oxidation within an entire surface to be processed of a substrate that has been processed by a processing module, when conveying the substrate by a vacuum conveying chamber that is provided between a vacuum processing chamber forming the processing module and a load lock chamber.SOLUTION: A vacuum processing device includes: the processing module; the load lock chamber for switching an atmosphere between a vacuum atmosphere and a normal pressure atmosphere; the vacuum conveying chamber which is provided between the vacuum processing chamber and the load lock chamber via a partition valve and in which the substrate is conveyed between the vacuum processing chamber and the load lock chamber; an inert gas supply section provided in the vacuum conveying chamber for supplying an inert gas to a side of the surface to be processed in the processed substrate on which the processing has been performed, over a full width of a conveying area along the conveying area of the substrate; and an exhaust port that is provided in the vacuum conveying chamber. Thus, moisture within the vacuum conveying chamber is prevented from being deposited over the entire surface to be processed of the substrate, and the oxidation can be prevented within the entire surface to be processed.

Description

  The present invention relates to a vacuum processing apparatus for forming a film on a substrate in a vacuum atmosphere.

  In the manufacturing process of a semiconductor device, various processes are performed in a vacuum atmosphere on a semiconductor wafer (hereinafter referred to as “wafer”) as a substrate. As a vacuum processing apparatus for performing these various processes, for example, a vacuum transfer chamber configured in a vacuum atmosphere, a load lock chamber, a normal pressure transfer chamber configured in a normal pressure atmosphere, and a processing module are provided. The wafers configured and processed by the processing module are transferred in the order of the vacuum transfer chamber, the load lock chamber, and the normal pressure transfer chamber, and stored in the transfer container. Patent Documents 1 and 2 show such a vacuum processing apparatus.

The processing module may be configured as a film forming module that performs so-called CVD (Chemical Vapor Deposition) in which a processing gas containing a thin film material is supplied to a heated wafer to form the thin film. As the processing gas, for example, TiCl ₄ (titanium tetrachloride) gas that is a gas containing a halogen compound is used, and a TiN (titanium nitride) film may be formed on the wafer W in some cases.
JP 2001-345279 A JP2007-165644

  When the thickness of the TiN film formed using the above vacuum processing apparatus is set to 5 nm or less, the distribution of the resistance value of the TiN film in the surface of the wafer becomes relatively large. As a result of the analysis, the cause of the large variation is considered as follows.

In the film forming module, the purge gas is supplied after the TiCl ₄ gas is supplied, and the atmosphere around the wafer is replaced with the purge gas atmosphere from the TiCl ₄ gas atmosphere. However, it is difficult to completely perform this replacement, and a TiN film is formed on the surface of the wafer transferred from the film forming module to the vacuum transfer chamber, and TiCl ₄ molecules remain in the TiN film. It has become. Further, since the wafer is heated during the film forming process, the temperature of the wafer when being transferred from the film forming module to the vacuum transfer chamber is relatively high. On the other hand, the vacuum transfer chamber is in a vacuum atmosphere as described above, but the atmosphere contains a small amount of moisture.

Since the temperature of the wafer is high as described above, a reaction occurs between TiCl ₄ on the wafer surface and the moisture as shown in the following formula 1 even if the moisture in the vacuum transfer chamber is small, and in TiCl ₄ Titanium atoms are oxidized and TiO ₂ (titanium oxide) is generated as a foreign substance. It is considered that the above-described variation in resistance value occurs due to such non-uniform oxidation occurring within the wafer surface.
2TiCl ₄ + 2H ₂ O → TiO ₂ + 4HCl Formula 1

In the above-mentioned Patent Document 1, it is shown that N ₂ gas is supplied to the vacuum transfer chamber. However, this is performed in order to prevent the oil from diffusing from the vacuum pump. The problem is not focused on. Further, in each drawing of Patent Document 1, it is shown that N ₂ gas is locally supplied to the vacuum transfer chamber and the N ₂ gas is exhausted locally in the vacuum transfer chamber. Since the degree of contact between the wafer and moisture varies at various locations in the vacuum transfer chamber, variations in the degree of oxidation occur at various portions within the surface of the wafer. That is, Patent Document 1 cannot solve the above problem. Further, in the vacuum processing apparatus of Patent Document 2, an air curtain provided with a large number of gas outlets and a large number of exhaust ports in order to partition the atmosphere of each chamber between the atmospheric pressure transfer chamber and the load lock chamber. A forming portion is formed. However, Patent Document 2 does not focus on the problem of oxidation occurring in the vacuum transfer chamber as described above, and there is no motivation to solve the problem.

  The present invention has been made under such circumstances, and an object of the present invention is to provide a vacuum transfer chamber in which a substrate processed by a processing module is provided between a vacuum processing chamber and a load lock chamber constituting the processing module. It is to provide a technique capable of preventing oxidation over the entire surface of the substrate to be processed.

The vacuum processing apparatus of the present invention includes a processing module including a vacuum processing chamber for processing a substrate in a vacuum atmosphere,
A load lock chamber for switching the atmosphere between a vacuum atmosphere and a normal pressure atmosphere;
A vacuum transfer chamber provided between the vacuum processing chamber and the load lock chamber via a gate valve, and a substrate is transferred between the vacuum processing chamber and the load lock chamber by a substrate transfer mechanism;
A vacuum chamber is provided in the vacuum transfer chamber so as to supply an inert gas to the processing surface side of the substrate along the transfer region of the processed substrate where the processing has been performed, over the entire width of the transfer region. An active gas supply unit;
And an exhaust port provided in the vacuum transfer chamber.

  According to the present invention, in the vacuum transfer chamber, the inert gas supply unit that supplies the inert gas to the processing surface side of the substrate is provided along the transfer region of the processed substrate that has been subjected to the processing. Since the substrate is transferred while the surface to be processed is exposed to the inert gas, adhesion of moisture is suppressed on the entire surface to be processed, and as a result, oxidation is suppressed on the entire surface to be processed.

It is a cross-sectional top view of the vacuum processing apparatus which concerns on embodiment of this invention. It is a vertical side view of a vacuum processing apparatus. It is a top view of the shower plate provided in the 2nd conveyance chamber which comprises a vacuum processing apparatus. It is a top view of the shower plate provided in the load lock chamber which comprises a vacuum processing apparatus. It is a vertical side view of the film-forming module which comprises a vacuum processing apparatus. It is explanatory drawing which shows conveyance of the wafer in a vacuum processing apparatus. It is explanatory drawing which shows conveyance of the wafer in a vacuum processing apparatus. It is explanatory drawing which shows conveyance of the wafer in a vacuum processing apparatus. It is explanatory drawing which shows conveyance of the wafer in a vacuum processing apparatus. It is a schematic diagram which shows the wafer in conveyance. It is a vertical side view of the 2nd conveyance chamber of the vacuum conveyance apparatus of a comparative example, and a load lock chamber. It is a top view of the disc applied to the gas shower plate of a vacuum processing apparatus. It is a top view which shows another 2nd conveyance chamber. It is a vertical side view of another 2nd conveyance chamber.

  A vacuum processing apparatus 1 according to an embodiment of the present invention will be described with reference to a transverse plan view of FIG. 1 and a longitudinal side view of FIG. The vacuum processing apparatus 1 forms a laminated film composed of a Ti (titanium) film and a TiN film on a wafer W. The vacuum processing apparatus 1 includes a first transfer chamber (normal pressure transfer chamber) 11, an alignment chamber 20, load lock chambers 31 and 32, a second transfer chamber (vacuum transfer chamber) 41, and film forming modules 71 to 74. . The first transfer chamber 11 is connected to the second transfer chamber 41 through load lock chambers 31 and 32. The second transfer chamber 41 is connected to the film forming modules 71 to 74. The film forming modules 71 and 72 form a TiN film on the wafer W, and the film forming modules 73 and 74 form a Ti film on the wafer W.

  The first transfer chamber 11 constitutes a loader module that carries the wafer W into and out of the vacuum processing apparatus 1 and has a rectangular shape in plan view. Assuming that the length direction of the first transfer chamber 11 is the left-right direction, a mounting table 12 is provided on the front side of the first transfer chamber 11 and is a carrier that is a transfer container for storing a plurality of wafers W. C is placed. On the front wall of the first transfer chamber 11, an open / close door 13 that is opened and closed together with a lid (not shown) provided on the carrier C mounted on the mounting table 12 is provided. The inside of the first transfer chamber 11 is a normal pressure atmosphere, and a first wafer transfer mechanism 14 that is an articulated arm is provided in the first transfer chamber 11.

As shown in FIG. 2, a fan filter unit (FFU) 16 is provided above the first wafer transfer mechanism 14 and supplies N ₂ (nitrogen) gas that has been cleaned downward. An exhaust port 17 is open at the bottom of the first transfer chamber 11. In the figure, 18 is an exhaust pipe having one end connected to the exhaust port 17, and the other end of the exhaust pipe 18 is connected to the FFU 16 via an exhaust mechanism 19 constituted by an exhaust fan or the like. The N ₂ gas supplied from the FFU 16 into the first transfer chamber 11 is exhausted from the exhaust port 17 by the exhaust mechanism 19 and then supplied to the FFU 16. Then, after being cleaned by the FFU 16, it is supplied again downward in the first transfer chamber 11. That is, the N ₂ gas circulates in the exhaust pipe 18 and the first transfer chamber 11.

  As shown in FIG. 1, the alignment chamber 20 is connected to the left side wall of the first transfer chamber 11 when the first transfer chamber 11 is viewed from the mounting table 12. The alignment chamber 20 adjusts the orientation and eccentricity of the wafer W. The first wafer transfer mechanism 14 can transfer the wafer W between the alignment chamber 20, the carrier C, and the load lock chambers 31 and 32.

  At the rear of the first transfer chamber 11, load lock chambers 31, 32 are arranged on the left and right, respectively. The load lock chambers 31 and 32 switch the internal atmosphere between a normal pressure atmosphere and a vacuum atmosphere while the wafer W is in a standby state. In FIG. 2, the load lock chamber 32 is shown as a representative, but the load lock chamber 31 is similarly configured. The load lock chambers 31 and 32 will be described in more detail later.

  Behind the load lock chambers 31 and 32, a second transfer chamber 41 having a hexagonal shape in plan view is provided. The inside of the second transfer chamber 41 is a vacuum atmosphere. In the figure, reference numeral 42 denotes a second wafer transfer mechanism, which is configured as an articulated arm. The second wafer transfer mechanism 42 transfers the wafer W in the second transfer chamber 41, and between the second transfer chamber 41 and the film forming modules 71 to 74 and the second transfer chamber 41. Wafers W can be transferred between the load lock chambers 31 and 32, respectively.

As shown in FIG. 2, a gas supply port 43 is opened in the ceiling portion of the second transfer chamber 41, and a gas supply pipe is connected to the supply port 43 from the outside of the second transfer chamber 41. One end of 44 is connected. The other end of the gas supply pipe 44 is connected to the N ₂ gas supply source 45, N ₂ gas is an inert gas supply port 43 is supplied from the N ₂ gas supply source 45. Further, a circular shower plate 51 and a support portion 52 that horizontally supports the shower plate 51 are provided in the second transfer chamber 41. The support portion 52 surrounds the side periphery of the shower plate 51, and the shower plate 51 is placed in the second transfer chamber 41 so as to face the surface (surface to be processed) of the wafer W transferred in the second transfer chamber 41. To support. The interior of the second transfer chamber 41 is vertically divided by the shower plate 51 and the support portion 52, and a diffusion space 46 in which the N ₂ gas supplied from the supply port 43 diffuses is provided above the shower plate 51 and the support portion 52. Form.

In the figure, 53 is a hole drilled in the thickness direction of the shower plate 51 which is an inert gas supply unit. A large number of holes 53 are formed dispersed in the entire surface of the shower plate 51, and are provided so that the N ₂ gas diffused in the diffusion space 46 can be supplied to the entire lower region of the shower plate 51. . FIG. 3 shows the upper surface of the shower plate 51. The shower plate 51 is a so-called punching plate. Since such a punching plate has a large number of holes, it is defined as a porous portion in this specification.

By the way, as will be described later, the wafer W processed by the film forming module 71 or 72 is transferred to the load lock chamber 31 or 32 via the second transfer chamber 41. The transfer area of the wafer W in the second transfer chamber 41 at the time of transfer is indicated by 54 and surrounded by a chain line in FIGS. As shown in FIG. 3, the shower plate 51 is configured so that N ₂ gas can be supplied to the entire surface of the wafer W over most of the transfer region 54. In other words, the shower plate 51 is placed on the surface of the wafer W to be transferred in the transfer area 54 along the transfer area 54 of the wafer W in the second transfer chamber 41 over the entire width of the transfer area 54. It is configured to be able to supply N ₂ gas. With such a configuration, N ₂ gas is supplied to the entire surface of the wafer W that is being transferred through the transfer region 54, thereby preventing moisture from adhering to the entire surface of the wafer W. As a result, oxidation can be suppressed over the entire surface of the wafer W.

  The relationship between the transfer area 54 and the shower plate 51 will be described in more detail. In order to obtain the effect of suppressing oxidation over the entire surface of the wafer W, the area of the area where the gas can be supplied in the transfer area 54 by the shower plate 51 (the gas supply area on the transfer area) with respect to the entire area of the transfer area 54 Is configured to be, for example, 70% or more, preferably 80% or more. As described above, since the shower plate 51 can supply gas to the entire lower region, in this example, the area of the gas supply region on the transfer region is the area of the shower plate 51.

  Returning to FIG. 2, the description will be continued. An exhaust port 47 is opened at the bottom of the second transfer chamber 41, and one end of an exhaust pipe 48 is connected to the exhaust port 47 from the outside of the second transfer chamber 41. The other end of the exhaust pipe 48 is connected to a dry pump 49 that is an exhaust mechanism. A baffle plate (buffer plate) 55 and a support portion 56 are provided below the transfer area 54 of the wafer W and above the exhaust port 47. The baffle plate 55 is formed in a horizontal circular ring shape so as to surround the lower side of the second wafer transfer mechanism 42. The baffle plate 55 is a punching plate similar to the shower plate 51, and a large number of holes 57 drilled in the thickness direction are dispersed throughout the entire surface of the plate. The support part 56 surrounds the side periphery of the baffle plate 55 and supports the baffle plate 55 horizontally. The inside of the second transfer chamber 41 is vertically divided by the baffle plate 55 and the support portion 56, and an exhaust space 58 is formed below the baffle plate 55 and the support portion 56.

The exhaust space 58 is exhausted by the dry pump 49, whereby the inside of the second transfer chamber 41 is exhausted from each hole 57 of the baffle plate 55. That is, exhaust is performed in a distributed manner in a region where exhaust can be performed by the exhaust port 47 (region facing the exhaust port). The reason why the exhaust is performed while being dispersed in this way is to prevent the N ₂ gas supplied to a relatively wide range in the transfer area 54 of the wafer W by the shower plate 51 from being exhausted locally. It is. More specifically, in order to prevent local exhaust in this way, it is possible to prevent the N ₂ gas flow rate and flow velocity from being biased in each part of the transfer area 54 of the wafer W, and thereby the N ₂ gas air flow. This is to suppress the occurrence of variation in the distribution of the. By suppressing the variation in the air flow distribution, moisture adhesion on the surface of the wafer W can be suppressed with high uniformity, and the degree of oxidation suppression can be achieved.

Subsequently, the description returns to the load lock chambers 31 and 32. Similar to the second transfer chamber 41, these load lock chambers 31 and 32 are also configured to form a N ₂ gas stream with high uniformity in the transfer region of the wafer W. Since the load lock chambers 31 and 32 are configured in the same manner as described above, the load lock chamber 32 shown in FIG. 2 will be described as a representative here. In the figure, 33 is a stage on which the wafer W is placed. In the figure, 34 is a lifting pin that protrudes and sinks on the surface of the stage 33 and delivers the wafer W between the first wafer transfer mechanism 14 and the second wafer transfer mechanism 42 and the stage 33. In the figure, reference numeral 35 denotes a gas supply port opened in the ceiling portion in the load lock chamber 32. An N ₂ gas supply source 36 is connected to the supply port 35 through a gas supply pipe 37. Reference numeral 38 denotes a shower plate, which is configured in the same manner as the shower plate 51 of the second transfer chamber 41, in order to suppress oxidation by supplying N ₂ gas to the entire surface of the wafer W transferred in the load lock chamber 32. Is provided. Reference numeral 39 denotes a hole in the shower plate 38.

FIG. 4 shows the upper surface of the shower plate 38. In FIG. 4, the transfer area 61 of the wafer W in the load lock chamber 32 is surrounded by a chain line. The transfer area 61 is a transfer area of the wafer W when being transferred from the second transfer chamber 41 to the load lock chamber 32 as described above. Like the shower plate 51, the shower plate 38 can supply N ₂ gas to the surface of the wafer W transferred along the transfer region 61 along the transfer region 61 over the entire width of the transfer region 61. It is configured. In order to obtain the effect of suppressing the oxidation in the entire surface of the wafer W, the area of the region in which the gas can be supplied in the transfer region 61 by the shower plate 38 with respect to the entire transfer region 61 is, for example, 70% or more, preferably 80%. It is comprised so that it may become more than%. Like the shower plate 51, the shower plate 38 can supply gas to the entire area below it. In this example, the area of the region where the gas can be supplied in the transfer region 61 is the area of the shower plate 38.

Returning to FIG. 2, reference numeral 62 in the drawing is a support portion that horizontally supports the shower plate 38, surrounds the side periphery of the shower plate 38, and partitions the interior of the load lock chamber 32 together with the shower plate 38. 63 is an N ₂ gas diffusion space formed above the shower plate 38 and the support 62. An exhaust port 64 opens at the bottom of the load lock chamber 32. An exhaust pipe 65 connects the dry pump 66 and the exhaust port 64, and a valve V1 is interposed therebetween.

A baffle plate 67 composed of a punching plate is provided above the exhaust port 64 and below the transfer area 61 of the wafer W. In the figure, reference numeral 68 denotes a hole in the baffle plate 67. Similar to the baffle plate 55 of the second transfer chamber 41, the baffle plate 67 is provided to exhaust each part of the transfer region 61 of the wafer W with high uniformity and to improve the uniformity of the N ₂ gas air flow distribution. Yes. The baffle plate 67 is configured in a ring shape so as to surround the stage 33, and is supported by a support portion 69 so as to surround its side periphery. The inside of the load lock chamber 32 is vertically divided by the baffle plate 67 and the support portion 69, and the lower portion of the baffle plate 67 and the support portion 69 is configured as an exhaust space 60 in which the exhaust port 64 is opened. The exhaust space 60 is exhausted through the exhaust pipe 65 by the dry pump 66, and thereby the inside of the load lock chamber 32 is exhausted from each hole 68 of the baffle plate 67. The exhaust amount from the baffle plate 67 is adjusted by the opening degree of the valve V1 of the exhaust pipe 65, and by adjusting the exhaust amount, the inside of the load lock chamber 32 is switched between the normal pressure atmosphere and the vacuum atmosphere. .

  Next, the film forming module 71 will be described with reference to FIG. 5 which is a longitudinal side view. The film forming module 71 forms a TiN film on the wafer W by ALD (Atomic Layer Deposition) which is a kind of CVD. In the figure, reference numeral 701 denotes a processing container constituting a vacuum processing chamber, which is opened and closed by a gate valve G described later. Reference numeral 702 denotes a mounting table for the wafer W, which includes a heater 712 for heating the mounted wafer W. In the figure, reference numeral 722 denotes a cover member that covers the outer peripheral side of the mounting region of the wafer W and the side peripheral surface of the mounting table 702 in the circumferential direction. In the figure, reference numeral 732 denotes a support member that supports the lower side of the mounting table 702. Reference numeral 742 denotes an elevating member that elevates and lowers the mounting table 702 between an upper position indicated by a solid line and a lower position indicated by a chain line via a support member 732. The lower position is a position where the wafer W is transferred to and from the second wafer transfer mechanism 42 that has entered the processing container 701 via the gate valve G, and the upper position is a processing position where the film is formed on the wafer W. is there.

  In the figure, reference numeral 752 denotes a bellows for keeping the inside of the processing container 701 airtight, and expands and contracts by raising and lowering the mounting table 702. Reference numeral 762 denotes three lifting pins (only two are shown in the figure), which is lifted and lowered by the lifting mechanism 772 and protrudes and sinks on the surface of the mounting table 702 through a hole 782 provided in the mounting table 702. The lift pins 762 transfer the wafer W between the mounting table 702 positioned at the lower position and the second wafer transfer mechanism 42 in the second transfer chamber 41. In the figure, reference numeral 703 denotes an exhaust duct that constitutes a part of the side wall of the processing container 701, and is configured in an annular shape so as to surround the periphery of the mounting table 702 in the upper position. The exhaust duct 703 is connected to an exhaust section 713 constituted by a vacuum pump or the like, and flows out from the mounting table 702 through an opening 723 formed along the circumferential direction on the inner peripheral surface of the exhaust duct 703. Exhaust the gas.

  In the figure, reference numeral 704 denotes a top plate member that constitutes the processing container 701. A concave portion is formed on the lower surface of the top plate member, and an inclined surface having a divergent shape from the center side to the outer peripheral side of the concave portion is formed. A space surrounded by the inclined surface and the upper surface of the mounting table 702 in the upper position constitutes a processing space 724 for the wafer W. A flat rim 714 is provided outside the inclined surface so as to face the cover member 722 of the mounting table 702.

The top plate member 704 is provided with gas supply paths 734 and 744 that are partitioned from each other, and the downstream ends of the gas supply paths 734 and 744 open above the center of the wafer W in the processing space 724. In the figure, reference numeral 754 denotes a dispersion plate provided on the central portion of the wafer W, which collides with the gas supplied from the gas supply paths 734 and 744. Part of the gas that collided with the dispersion plate 754 reaches below the dispersion plate 754 and reaches the central portion of the wafer W, and the remaining gas is guided by the dispersion plate 754 to change the flow direction, thereby changing the ceiling of the processing space 724. While being guided by the inclined surfaces of the top plate member 704, the top plate member 704 is supplied radially and radially along the radial direction from the center side to the outer peripheral side. The upstream end of the gas supply path 734 branches and is connected to an NH ₃ (ammonia) gas supply source 705 and an N ₂ gas supply source 715, respectively. Further, the upstream end of the gas supply path 744 branches and is connected to an N ₂ gas supply source 715 and a TiCl ₄ gas supply source 725, respectively.

A flow of processing in the film forming module 71 will be described. The wafer W mounted on the mounting table 702 at the lower position is heated by the heater 712, and the mounting table 702 is moved to the upper position. After the processing space 724 is exhausted and the pressure is adjusted, the processing space 724 is processed. Gas supply is performed in the order of TiCl ₄ gas, N ₂ gas, NH ₃ gas, and N ₂ gas. The TiCl ₄ gas supplied to the processing space 724 is adsorbed on the wafer W, and then reacts with the NH ₃ gas supplied to the processing space 724 to form a TiN molecular layer on the wafer W. TiCl ₄ gas, _{N 2} gas is supplied after the supply of the NH ₃ gas, TiCl ₄ gas remaining in the processing space 724 to remove the NH ₃ gas, _{N 2} gas atmosphere processing space 724 from those gas atmosphere This is a purge gas to be substituted. Assuming that supplying one gas in the order of the above TiCl ₄ gas, N ₂ gas, NH ₃ gas, and N ₂ gas is one cycle, this gas supply cycle is repeated a plurality of times, and a TiN molecular layer is formed on the wafer W. Are stacked to form a TiN film.

  The other film forming modules 72 to 74 will be described. The film forming module 72 is configured in the same manner as the film forming module 71 and forms a TiN film. The film forming modules 73 and 74 are configured in substantially the same way as the film forming modules 71 and 72 except that the gas supplied to the wafer W is different from that of the film forming modules 71 and 72. A film is formed.

  As illustrated in FIG. 1, the film forming modules 71 to 74 are provided so as to surround the second transfer chamber 41. The processing container 701 and the second transfer chamber 41 that constitute each of the film forming modules 71 to 74 are connected to each other via a gate valve G that is a partition valve. Each gate valve G is configured in the same manner, and the gate valve G interposed between the processing container 701 and the second transfer chamber 41 of the film forming module 71 shown in FIG. The valve main body G1 is provided, and the valve main body G1 moves up and down to switch between a state where the processing container 701 and the second transfer chamber 41 are airtightly partitioned from each other and a state where they are communicated with each other. FIG. 2 shows a state of being airtightly partitioned from each other.

  The second transfer chamber 41 and each of the load lock chambers 31 and 32 are also connected via a gate valve G, and each of the load lock chambers 31 and 32 and the first transfer chamber 11 are also gated. It is connected via a valve G. These gate valves G also communicate with each other in a state in which adjacent chambers are hermetically partitioned from each other, like the gate valve G interposed between the film forming module 71 and the second transfer chamber 41. Switch between states.

  By the way, the vacuum processing apparatus 1 is provided with a control unit 10 composed of, for example, a computer as shown in FIG. The control unit 10 includes a program, a memory, a CPU, and the like. A control signal is sent from the control unit 10 to each unit of the vacuum processing apparatus 1 to this program, and the wafer W transfer and film formation modules 71 to 74 described later are used. Instructions (each step) are incorporated so as to advance the processing of the wafer W. The program is stored in a storage medium such as a computer storage medium such as a flexible disk, a compact disk, a hard disk, an MO (magneto-optical disk), or a memory card and installed in the control unit 10.

  Next, the processing and transfer path of the wafer W in the entire vacuum processing apparatus 1 will be described. The wafer W stored in the carrier C mounted on the mounting table 12 is stored in the first transfer chamber 11 → the alignment chamber 20 → the load lock chamber 31 or 32 → the second transfer chamber 41 → the film forming module 73 or 74. It is conveyed in order, and a Ti film is formed on the surface. Thereafter, the film is transferred in the order of the second transfer chamber 41 → the film forming module 71 or 72, and a TiN film is laminated on the Ti film. The wafer W on which the TiN film is formed is transferred in the order of the second transfer chamber 41 → the load lock chamber 31 or 32 → the first transfer chamber 11 and returned to the carrier C.

A state in which the wafer W is transferred from the film forming module 71 toward the load lock chamber 32 in the transfer path of the wafer W will be described with reference to FIGS. In FIGS. 6 to 9, the flow of N ₂ gas formed in each chamber is indicated by arrows. In the second transfer chamber 41 and the load lock chamber 32, N ₂ gas is supplied and exhausted, respectively, and kept in a vacuum atmosphere at a predetermined pressure. The second wafer transfer mechanism 42 in the second transfer chamber 41 enters the film forming module 71 and receives the wafer W heated to a relatively high temperature by the film forming process (FIG. 6). Then, the gate valve G interposed between the second transfer chamber 41 and the film forming module 71 is closed (FIG. 7).

FIG. 10 is a schematic view of the wafer W carried into the second transfer chamber 41 as described above. As described in the section of the problem to be solved, a TiN film 21 is formed on the surface of the wafer W, and TiCl ₄ molecules 22 as a film forming material are attached to the TiN film 21. The shower plate 51 supplies N ₂ gas to most of the area in the transfer area 54 of the wafer W in the second transfer chamber 41, and the transfer area 54 is highly uniform from many locations below by the baffle plate 55. Since the air is exhausted, an air flow of N ₂ gas is formed with high uniformity throughout the transfer region 54. The wafer W is transferred while its entire surface is exposed to such airflow. Therefore, in the whole of each part surface of the the wafer W, the molecules 22 of TiCl ₄ contacts the molecules 23 of water, and molecules 23 of the water to remain in contact with the molecules 22 of TiCl _4, with high uniformity It is prevented. In other words, the oxidation by the water molecules 23 is suppressed on the entire surface of the wafer W, and the degree of suppression is uniform.

By being exposed to the N ₂ gas stream, the temperature of the wafer W gradually decreases, and the reactivity of the TiCl ₄ molecules 22 to the water molecules 23 decreases. While the transfer of the wafer W in the second transfer chamber 41 is continued, the gate valve G interposed between the second transfer chamber 41 and the load lock chamber 32 is opened (FIG. 8), and the wafer W is loaded into the load lock chamber. It is transported into 32 (FIG. 9). At this time, the uniformity of the N ₂ gas air flow distribution in each part of the wafer W transfer area 61 in the load lock chamber 32 is as high as the wafer W transfer area 54 in the second transfer chamber 41. The whole is conveyed while being exposed to such airflow. Therefore, similarly to the transfer in the second transfer chamber 41, the adhesion of the water molecules 23 on the surface of the wafer W can be suppressed with high uniformity in the entire surface during the transfer in the load lock chamber 32. .

Thereafter, the wafer W is placed on the stage 33 of the load lock chamber 32, the second wafer transfer mechanism 42 is withdrawn from the load lock chamber 32, and the load lock chamber 32 is interposed between the load lock chamber 32 and the second transfer chamber 41. When the intervening gate valve G is closed, the exhaust amount in the load lock chamber 32 decreases, and the pressure in the load lock chamber 32 increases. On the other hand, the wafer W continues to be exposed to N ₂ gas, so that the temperature further decreases, and the reactivity of the TiCl ₄ molecules 22 with respect to the water molecules 23 further decreases. When the load lock chamber 32 is in a normal pressure atmosphere, the wafer W is transferred to the first transfer chamber 11 as described above.
The transfer in the case where the wafer W is transferred from the film forming module 71 to the load lock chamber 32 has been described as a representative. However, the wafer W passes through the film forming module 72 and the load lock chamber 31, respectively, and the first transfer chamber. Also when returning to 11, the wafer W is exposed to the N ₂ gas stream as in the above-described transfer, and is transferred while suppressing the oxidation of the entire surface.

In order to clearly show the effects of the second transfer chamber 41 and the load lock chambers 31 and 32, the second transfer chamber 81 and the load lock chamber 82 will be described with reference to FIG. 11 as a comparative example. The difference between the second transfer chamber 41 and the load lock chamber 32 described above is that the gas transfer plate and the baffle plate are not provided in the second transfer chamber 81 and the load lock chamber 82. . The N ₂ gas supply ports 43 and 35 open to the bottoms of the second transfer chamber 81 and the load lock chamber 82, respectively. The N ₂ gas passes through a filter 83 provided in these supply ports 43 and 35. To be supplied indoors.

In FIG. 11, the flow of N ₂ gas is indicated by arrows as in FIGS. As shown in FIG. 11, the N ₂ gas locally supplied to the second transfer chamber 81 and the load lock chamber 82 is exhausted through the exhaust ports 47 and 64 that are locally opened after moving upward in the chamber. Being headed downward. As is clear from comparison between FIG. 11 and FIGS. 6 to 9, in the second transfer chamber 81 and the load lock chamber 82, the region where the N ₂ gas can be supplied to the surface of the wafer W is relatively long. small, therefore, the locations not supplied N ₂ gas on the surface of the wafer W being transported, and a portion where N ₂ gas is supplied will be formed. Since water molecules 23 may adhere and TiCl ₄ may be oxidized at locations where the N ₂ gas on the surface of the wafer W is not supplied, the gas shower plates 51 and 38 and the baffle plate 55 as in the vacuum processing apparatus 1 are likely to occur. , 67 is effective.

According to the vacuum processing apparatus 1 described above, the N ₂ gas is supplied to the entire surface of the wafer W transferred in the transfer area 54 over most of the transfer area 54 of the wafer W in the second transfer chamber 41. A shower plate 51 is provided. The shower plate 51, over the entire width of the wafer W of the transport region 54, since the N ₂ gas is supplied along the transport direction of the wafer W in the transfer area 54 of the wafer W, TiCl ₄ in the entire surface of the wafer W The generation of TiO ₂ due to the oxidation of is suppressed. As a result, the film quality of the TiN film can be improved.
Further, since baffle plates 55 are provided for exhausting the transfer region 54 from a number of locations on the back side of the wafer W, exhaust is performed with high uniformity from various locations in the transfer region 54 of the wafer W and formed in the transfer region 54. The uniformity of the N ₂ gas flow is improved. As a result, the oxidation of TiCl ₄ can be suppressed with high uniformity in each part of the entire surface of the wafer W. As a result, the yield of semiconductor products manufactured from the wafer W can be improved.

Further, the shower plate 38 is also provided in each load lock chambers 31 and 32, N ₂ gas is supplied to the transfer area 61 of the wafer W, since the N ₂ gas is supplied to the entire surface of the wafer W, more reliable In addition, oxidation of the entire surface of the wafer W can be suppressed. Further, the baffle plate 67 is also provided in each of the load lock chambers 31 and 32, and the uniformity of the N ₂ gas air flow formed in each part of the transfer area 61 of the wafer W can be increased. ₄ can be suppressed more uniformly.

Incidentally, FIG. 12 is a plan view of the disk 84. The disk 84 is a porous portion made of ceramics such as aluminum oxide or silicon carbide, and has fine holes formed on the surface and inside thereof, and can be ventilated from the surface side to the back surface side. This porous disk 84 may be used in place of the shower plates 51 and 38 described above. Since the circular plate 84 can supply gas to the entire lower region in the same manner as the shower plates 51 and 38, for example, the area thereof is preferably 70% or more with respect to the area of the transfer regions 54 and 61 of the wafer W, respectively. 80% or more.
Further, a ring-shaped plate may be formed from the above-described materials constituting the circular plate 84, and this ring-shaped plate may be used in place of the baffle plates 55 and 67.

Further, in the second transfer chamber 41, in order to increase the uniformity of the air flow distribution in the transfer area 54 of the wafer W, it is limited to providing a porous portion below the transfer area 54 of the wafer W. Absent. FIGS. 13 and 14 respectively show a transverse plan view and a longitudinal side view of the second transfer chamber 41 in which the porous portion is not provided. In the second transfer chamber 41, a plurality of exhaust ports 47 are distributed and opened on the bottom surface. As shown in FIG. 14, one end of an exhaust pipe 48 is connected to each exhaust port 47, and the other end of each exhaust pipe 48 joins and is connected to a dry pump 49. That is, the exhaust pipe 48 is configured as a manifold. Be configured to include such a manifold, the variation of the exhaust amount in each part of the transport region 54 of the wafer W that is suppressed, N ₂ gas supplied from the shower plate 51 is evacuated with high uniformity, the N ₂ gas Since the bias of the airflow can be suppressed, the same effect as when the baffle plate 55 is provided can be obtained. The load lock chambers 31 and 32 may also be configured to include a manifold. When a plurality of exhaust ports 47 are provided in this way, a plurality of dry pumps 49 are also provided, and each exhaust port 47 is individually connected to each dry pump 49 so that each dry pump 49 exhausts with the same exhaust amount. Good.

  By the way, in general, since halogen compounds have a relatively high reactivity with water, if they remain on the wafer W as described above, they are easily oxidized to generate foreign matter. Therefore, the second transfer chamber 41 is used to suppress this oxidation. In addition, it is effective that the load lock chambers 31 and 32 have the above-described configuration. However, even when a compound other than the halogen compound remains on the surface of the wafer W, the second transfer chamber 41 and the load lock chambers 31 and 32 can suppress oxidation of the compound. That is, the processing gas used in the film forming modules 71 and 72 is not limited to a gas containing a halogen compound.

Although the reactivity is lower than that of TiCl ₄ , the TiN film also reacts with water as shown in the following formula 2, and Ti in TiN is oxidized to generate TiO ₂ . Therefore, the vacuum processing apparatus 1 has an effect of preventing oxidation of the TiN film in addition to TiCl ₄ in the second transfer chamber 41 and the load lock chambers 31 and 32.
2TiN + 4H ₂ O → 2TiO ₂ + NH ₃ + H ₂ ... Formula 2

  Since the oxidation of TiN can be prevented in this way, the processing module connected to the second transfer chamber 41 is not limited to the film forming module that performs CVD. For example, it is assumed that an etching module that performs dry etching is connected to the second transfer chamber 41. When the wafer W having the TiN film exposed on the surface thereof is transferred to the carrier C through the second transfer chamber 41 and the load lock chambers 31 and 32 by the processing by the etching module, the second transfer chamber 41 and the load are transferred. In the lock chambers 31 and 32, oxidation of the TiN film can be suppressed over the entire surface of the wafer W.

Further, when a film forming module for forming a TiN film by PVD (Physical Vapor Deposition) instead of the film forming module 71 is connected to the second transfer chamber 41, the second transfer chamber 41, the load lock chamber 31, In 32, since the oxidation of the TiN film can be suppressed over the entire surface of the wafer W, the configuration of the vacuum processing apparatus 1 described above is effective. Further, in the vacuum processing apparatus 1 described above, a post-processing module that performs post-processing after forming the TiN film is connected to the second transfer chamber 41, and the wafer W on which the TiN film is formed by the film-forming module 71 has the second structure. You may make it convey from the conveyance chamber 41 to the said post-processing module. Also in this case, the oxidation of the entire surface of the wafer W can be suppressed from the time when the wafer W is transferred to the second transfer chamber 41 to the time when it is transferred to the post-processing module.

G Gate valve W Wafer 11 First transfer chamber 14 First transfer mechanism 31, 32 Load lock chamber 41 Second transfer chamber 42 Second transfer mechanism 71-74 Deposition module 38, 51 Shower plate 55, 67 Baffle plate

Claims (9)

A processing module including a vacuum processing chamber for processing a substrate in a vacuum atmosphere;
A load lock chamber for switching the atmosphere between a vacuum atmosphere and a normal pressure atmosphere;
A vacuum transfer chamber provided between the vacuum processing chamber and the load lock chamber via a gate valve, and a substrate is transferred between the vacuum processing chamber and the load lock chamber by a substrate transfer mechanism;
A vacuum chamber is provided in the vacuum transfer chamber so as to supply an inert gas to the processing surface side of the substrate along the transfer region of the processed substrate where the processing has been performed, over the entire width of the transfer region. An active gas supply unit;
A vacuum processing apparatus comprising: an exhaust port provided in the vacuum transfer chamber.   The vacuum processing apparatus according to claim 1, wherein the inert gas supply unit is provided to face a transfer region of the processed substrate.   The vacuum processing apparatus according to claim 1, wherein the inert gas supply unit includes a porous part that supplies the inert gas to the substrate in a shower shape.   The area of the gas supply region on the substrate transfer region by the inert gas supply unit is 70% or more of the total area of the processed substrate transfer region. The vacuum processing apparatus as described in one. The exhaust port is provided on the opposite side of the processed surface of the processed substrate,
5. The vacuum processing apparatus according to claim 1, wherein a buffer plate having a plurality of openings is provided in a region facing the exhaust port in order to distribute exhaust. . The processing module is configured to perform a film forming process on a substrate using a processing gas,
6. The vacuum processing apparatus according to claim 1, wherein the inert gas is supplied in order to prevent oxidation of a film forming material remaining on the substrate.   The vacuum processing apparatus according to claim 1, wherein a processing gas for performing a film forming process on the substrate includes a halogen compound.   The vacuum according to any one of claims 1 to 7, wherein the load lock chamber is provided with a porous portion for supplying an inert gas to the entire surface to be processed in a shower shape. Processing equipment. In the load lock chamber, an exhaust port is provided on the side opposite to the surface to be processed of the substrate,
The vacuum processing apparatus according to claim 8, wherein a buffer plate having a plurality of openings is provided in a region facing the exhaust port in order to distribute and exhaust the exhaust.

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