JP5218248B2 - Vapor phase growth apparatus and semiconductor device manufacturing method - Google Patents

Description

  The present invention relates to a vapor phase growth apparatus and a method for manufacturing a semiconductor device, and more particularly to a vapor phase growth apparatus provided with a continuous valve between a gas supply system and a reaction chamber and a method for manufacturing a semiconductor device.

  A semiconductor integrated circuit device employs multilayer wiring as semiconductor elements and wiring are miniaturized as the degree of integration increases. In order to guarantee high-speed operation of miniaturized wiring, it is desirable to reduce the resistance of the wiring. Instead of aluminum, copper having a lower resistance is used as a wiring material. When forming a copper wiring, there is a limit in forming a copper layer and finely patterning using photolithography. A damascene process is employed to form miniaturized copper wiring. Wiring grooves and / or via holes are formed in the insulating layer, the grooves and / or via holes are filled with a copper wiring layer, and the excess copper wiring layer on the insulating layer is removed by chemical mechanical polishing (CMP) or the like. The damascene process includes a single damascene process and a dual damascene process.

  In the single damascene process, an insulating layer is formed, a wiring recess is opened in the insulating layer, embedded in the copper wiring layer, and unnecessary portions are removed by CMP to form a copper wiring. When forming a wiring having a via conductor, first a via hole is opened in the lower insulating layer, the via conductor is buried, then an upper insulating layer is formed, a wiring trench (trench) is opened, and the copper wiring is formed. Embed the layer. In the dual damascene process, an insulating layer is formed, a recess having a wiring trench (trench) and a via hole is formed in the insulating layer, the recess is filled with a copper wiring layer, and unnecessary portions are removed by CMP.

  Copper has the property of diffusing into the insulating layer and degrading the insulating properties of the insulating layer. For this reason, when forming a copper wiring by a damascene process, a barrier metal layer having a function of preventing copper diffusion is first formed, and a copper layer is formed thereon. As the barrier metal, a nitride such as titanium nitride TiN or tantalum nitride TaN, tantalum Ta, or the like is used. The barrier metal layer shields copper diffusion laterally and downward from the copper wiring. Copper diffusion upward from the copper wiring cannot be prevented by the barrier metal layer underlying the copper wiring layer.

  In the copper wiring subjected to CMP, the copper layer is exposed on the surface. In order to prevent copper from diffusing from the copper layer to the upper insulating layer, the surface on which the copper wiring is formed is covered with a copper diffusion preventing insulating film. The copper diffusion preventing insulating film also has a function as an etching stopper when etching the upper interlayer insulating layer. The copper diffusion prevention insulating film is usually formed of silicon nitride SiN, silicon carbide SiC, or the like. The copper wiring and the copper diffusion prevention insulating film have poor adhesion and may cause problems such as peeling.

  Insulating films such as a copper diffusion preventing insulating film are often formed by chemical vapor deposition (CVD). Plasma-enhanced chemical vapor deposition (PE-CVD) is a CVD for converting a reaction gas into a plasma, and the reaction temperature can be lowered by utilizing the energy of the plasma. A semiconductor manufacturing apparatus that performs film formation by CVD or PE-CVD includes a reaction chamber that performs a film formation reaction, a gas supply system that supplies a source gas to the reaction chamber, and an exhaust system that discharges residual gas in the reaction chamber. A mass flow controller (MFC) is connected to the gas supply system in order to control the gas flow to be supplied. When film formation is performed under reduced pressure, a vacuum exhaust pump is connected to the exhaust system. In order to prevent an undesirable reaction between gases, a plurality of gas supply systems are often employed.

  In order to prevent outside air from entering the gas supply system when the reaction chamber is opened, a valve is disposed on the gas supply system output side of the upstream piping of the reaction chamber. In the case of a configuration that can supply a plurality of gases, a piping configuration that joins a plurality of pipings on the upstream side of the reaction chamber is often used. A configuration in which valves are installed before and after the MFC of each gas supply pipe is employed so that an unintended gas does not flow back to the MFC.

Japanese Patent Laid-Open No. 8-139041 JP-A-8-274029

  One object of the present invention is to provide a vapor phase growth apparatus that can suppress the influence of residual gas.

  Another object of the present invention is to provide a vapor phase growth apparatus capable of improving the surface treatment of copper wiring before forming a copper diffusion preventing insulating film.

  A further object of the present invention is to provide a method of manufacturing a semiconductor device that can suppress the influence of residual gas.

  Still another object of the present invention is to provide a semiconductor device manufacturing method capable of manufacturing a semiconductor device having a copper wiring having a good surface condition and low resistance.

According to one aspect of the present invention,
A reaction chamber for film formation;
A first gas supply system for supplying a first gas into the reaction chamber, a first gas supply system including a plurality of pipes provided with a mass flow controller and before and after the valve,
A first connection pipe connecting the first gas supply system and the reaction chamber;
A first continuous valve including two or more valves provided in the first connection pipe and capable of shutting off the supply of the first gas to the reaction chamber;
An exhaust pipe connected to the reaction chamber;
A waste gas pipe connected to the exhaust system pipe;
A first discarded Gasubaru Bed for controlling connection and disconnection between the discarded gas pipe and the first connection pipe of the first gas supply system downstream and the first continuous valve upstream,
The a, and one valve of the first continuous valve and said first abandoned gas valve is, one normally open and the other is a different type of normally closed, interlocked with the first driving gas A vapor phase growth apparatus in which another valve of the first continuous valve is driven by a second driving gas is provided.

According to another aspect of the invention,
Preparing a semiconductor substrate on which damascene wiring is formed;
A first gas supply system for supplying a first gas to the reaction chamber, the first gas supply system including a mass flow controller and a plurality of pipes including valves before and after the first gas supply system ; the first connection pipe of the gas supply system and to connect the reaction chamber, provided in the first connection pipe, can shut off the supply to the reaction chamber of the first gas, two or more valves A first continuous valve including: an exhaust system pipe connected to the reaction chamber; a waste gas pipe connected to the exhaust system pipe; a downstream of the first gas supply system and an upstream of the first continuous valve first discarded possess a Gasubaru blanking, and the first one of the valve and the first abandoned gas valve continuous valve for controlling the connection and disconnection of the first connection pipe and the discarded gas pipe But one is normally open and the other is normally closed The semiconductor substrate is carried into the reaction chamber of the vapor phase growth apparatus that is linked with the first driving gas and that is driven by the second driving gas. and a step of performing a first surface treatment by supplying a first process gas as the first gas from the first gas supply system,
A step of evacuating the closed first gas supply system, to close only one valve of the first continuous valve, the residual gas by opening the first abandoned gas valve,
Supplying a second processing gas as the first gas from the first gas supply system to perform a second surface treatment;
A method for manufacturing a semiconductor device is provided.

  Since the continuous valves are not closed simultaneously, but only one valve is closed, gas confinement is suppressed.

1A and 1B are cross-sectional views illustrating a configuration example of a target semiconductor device and a configuration of a manufactured sample. When, When, 1C to 1H are diagrams showing a sample manufacturing process using a vapor phase growth apparatus according to a comparative example. 1I and 1J are a micrograph showing the surface state of the prepared sample and a graph showing the measured resistance. When, 2A, 2B, and 2C are diagrams schematically showing the configuration of the vapor phase growth apparatus according to the modified embodiment. 3A and 3B are a micrograph showing the surface state of a sample produced using the vapor phase growth apparatus according to the example and a graph showing the measured resistance.

FIG. 1A schematically shows a configuration example of a semiconductor device to be studied. An element isolation trench is formed on the surface of the silicon substrate 11, and an oxide film is buried to form a shallow trench isolation 12. In the active region defined by the shallow trench isolation 12, an insulating gate electrode is formed by a gate insulating film 13 formed of an oxide film containing nitrogen and a gate electrode 14 containing a silicon layer. The gate insulating film may have a stacked structure. When the stacked structure is employed, for example, the first gate insulating film may be formed of a silicon oxide film, and the second gate insulating film may be formed of a silicon nitride film having a high dielectric constant, a hafnium oxide (HfO ₂ ) film, or the like. A side wall of the gate electrode is covered with a sidewall spacer 17 formed of an insulating film such as a silicon oxide film. Source / drain regions 18 having extension regions are formed on both sides of the gate electrode.

  An etch stopper film 20 made of a SiN film is formed to cover the gate electrode and the sidewall spacer. A lower interlayer insulating film 21 made of phosphosilicate glass is formed so as to cover the etch stopper film 20. A contact hole reaching the transistor from the surface of the lower interlayer insulating film 21 is formed, a Ti layer, a TiN layer, and a W layer are stacked, and unnecessary portions are removed by CMP to form a tungsten plug 22.

  On the lower interlayer insulating film 21, a first interlayer insulating film IL1 is formed. The first interlayer insulating film is formed by stacking, for example, a low dielectric constant insulating film 24 and a silicon oxide film 25. A trench for wiring is formed so as to penetrate the first interlayer insulating film IL1, and a barrier metal layer 26 and a copper wiring layer 27 are embedded. For example, a barrier metal layer 26 of Ta, TiN, TaN, etc., and a copper seed layer formed thereon are formed by sputtering, and a copper layer is formed thereon by electrolytic plating, and is formed on the first interlayer insulating film IL1. Unnecessary portions are removed by chemical mechanical polishing (CMP).

A copper diffusion prevention insulating film 29 made of SiC is formed so as to cover the copper wiring layer 27, and a second interlayer insulating film IL2 is formed thereon. The SiC film is formed by plasma enhanced chemical vapor deposition (PE-CVD) using tetramethylsilane Si (CH ₃ ) ₄ and carbon dioxide CO ₂ as source gases. The second interlayer insulating film IL2 is formed by stacking, for example, a silicon oxide film 40, a low dielectric constant insulating film 41, and a silicon oxide film. In the second interlayer insulating film IL2, trenches and via holes for a dual damascene structure are formed, and a barrier metal layer 44 and a copper wiring layer 45 are embedded. After the unnecessary metal layer is removed by CMP, a copper diffusion preventing insulating film 47 is formed by SIC. Further, an interlayer insulating film is formed and copper wiring is embedded. A necessary number of wirings are formed in the same process.

  The SiC film has weak adhesion to the copper layer and may cause peeling. In order to improve the adhesion of the SiC film, it has been studied to perform a surface treatment after forming the copper wiring layer.

  FIG. 1B is a schematic cross-sectional view of a copper wiring structure produced by the inventors in a preliminary experiment. A trench and a via hole are formed in the stack of the first copper diffusion prevention insulating film CDB1 and the first interlayer insulating film IL1 with respect to the lower layer wiring, a barrier metal layer BM and a copper layer CW are formed, and CMP is performed to form a dual damascene wiring DDW. Form. In the sample tested, the first copper diffusion prevention insulating film was formed of a SiC film having a thickness of 50 nm, and the interlayer insulating film was formed of a SiOC film having a thickness of 500 nm. The trench has a depth of 300 nm and a width of 0.2 μm, and the via has a depth of 250 nm and a width of 0.15 μm. The barrier metal layer was formed of a TaN layer having a thickness of 20 nm. After the dual damascene copper wiring DDW is formed, the wafer is carried into the reaction chamber of the PE-CVD apparatus, surface treatment SP is performed, and then a second copper diffusion prevention insulating film CDB2 made of a SiC layer having a thickness of 50 nm is grown. To do. The surface treatment is performed in-situ in the reaction chamber of the PE-CVD apparatus. Subsequently, a second interlayer insulating film IL2 is formed on the second copper diffusion preventing insulating film CDB2 by PE-CVD.

  1C to 1F are schematic diagrams for explaining a surface treatment performed in a PE-CVD apparatus. The state of the gas piping of the PE-CVD apparatus is shown on the upper side, and the state of the copper wiring is selectively schematically shown on the lower side.

  As shown in FIG. 1C, the PE-CVD apparatus includes a reaction chamber RC equipped with a high-frequency power source PS, gas supply systems 1a, 1b, and 1c (sometimes collectively referred to as 1) for supplying a raw material gas and the like. Pipes connecting the gas supply systems 1a, 1b, and 1c to the reaction chamber RC, a vacuum exhaust system VP that exhausts unnecessary gas from the reaction chamber RC, and an output (downstream) side of the gas supply systems 1a and 1b is connected to the vacuum exhaust system VP. A waste gas line 3 connected to Triple valves 2a and 2b are connected between the gas supply systems 1a and 1b and the reaction chamber RC. The triple valves 2a and 2b merge on the downstream side. The gas supply system 1c is connected to the joined pipe.

A plurality of gas supply sources are connected to a plurality of gas pipes each having a mass flow controller (MFC) and front and rear shut-off valves. The valve is normally closed (indicated by a cross) and is supplied with a driving gas to be opened. The flow path of the driving gas is indicated by a broken line. A white valve indicates an open state supplied with driving gas, and a solid valve indicates a normally closed state. In the figure, a silane SiH ₄ pipe connected to the triple valve 2a as the gas supply system 1a, a nitrogen N ₂ pipe, an ammonia NH ₃ pipe connected to the triple valve 2b as the gas supply system 1b, and carbon dioxide CO ₂ Examples of the piping and gas supply system 1c include tetramethylsilane Si (CH ₃ ) ₄ piping connected to the downstream side of the triple valve 2b. 1C to 1F, since the valves before and after the mass flow controller of the gas supply system 1c are always closed, the description thereof is omitted. The valve V14 for turning on / off the upstream connection of the waste gas line 3 and the triple valve 2a and the valve V24 for turning on / off the upstream connection of the waste gas line 3 and the triple valve 2b are normally closed. When the driving gas is supplied and opened, the downstream side of the gas supply system pipes 1a and 1b and the vacuum exhaust system VP are selectively connected.

  The triple valve 2a (2b) includes first, second, and third normally closed valves V11, V12, V13 (V21, V22, V23) that are linked. That is, all the illustrated valves are normally closed. A filter F1 (F2) is connected between the second and third valves V12, V13 (V22, V23) of the triple valve 2a (2b), and between the first and second valves V11, V12 (V21, V22). Is set to be as long as, for example, about 160 cm so that it can be separated during maintenance work. The distance between the second and third valves V12, V13 (V22, V23) is relatively short, for example, about 20 cm.

  The high frequency power source PS is a plasma power source when performing PE-CVD in the reaction chamber, and supplies high frequency power of 13.56 MHz, for example, to the counter electrode PP in the reaction chamber RC. The lower electrode of the counter electrode PP also serves as the susceptor of the substrate SUB.

As shown in FIG. 1C, with the valves V14 and V24 at the inlet of the waste gas line 3 closed, the driving gas is supplied to the silane SiH ₄ line of the gas supply system 1a and the ammonia NH ₃ line of the gas supply system 1b. The driving gas is also supplied to the continuous valves 2a and 2b, the valve is opened, silane SiH ₄ is diluted with ammonia NH ₃ , and a predetermined minute flow rate is made to flow on the substrate SUB. The temperature of the substrate is about 400 ° C. The reaction chamber RC is evacuated by a vacuum exhaust system VP and has a reduced pressure atmosphere of about 260 Pa. It is considered that silane is decomposed on the substrate surface to form an Si layer in atomic layer units.

  As shown in FIG. 1D, the gas supply systems 1a, 1b, the triple valves 2a, 2b are stopped, all the valves of the gas supply system pipe 1 and the triple valves 2a, 2b are closed, and the waste gas line 3 Driving gas is supplied to the inlet valves V14 and V24 to open them. The residual gas in the reaction chamber RC is exhausted, and the residual gas downstream of the gas supply system pipes 1a and 1b is also exhausted.

As shown in FIG. 1E, the drive gas of the valves V14 and V24 at the inlet of the waste gas line 3 is stopped and the valves V14 and V24 are closed, the ammonia NH ₃ line of the gas supply system 1b and the nitrogen N ₂ line of the gas supply system 1a, The driving gas is supplied to the triple valves 2a and 2b to open the valve, and ammonia diluted with nitrogen is allowed to flow into the reaction chamber RC at a predetermined flow rate to form a reduced pressure atmosphere of about 260 Pa. The temperature of the substrate SUB is about 400 ° C. Plasma is generated by turning on the high frequency power supply PS. It is considered that the Si layer in atomic units on the substrate surface is nitrided (becomes SiN-like composition) by the plasma containing ammonia. However, the formed layer was extremely thin and could not be detected by a cross-sectional SEM or the like.

  As shown in FIG. 1F, the high frequency power supply PS is turned off, the driving gas of the gas supply systems 1a, 1b and the triple valves 2a, 2b is stopped, and all the valves of the gas supply system 1 and the triple valves 2a, 2b are turned on. The drive gas is supplied to the valves V14 and V24 at the inlet of the waste gas line 3 to open the valves V14 and V24. The residual gas in the reaction chamber RC is exhausted, and the residual gas downstream of the gas supply system pipes 1a and 1b is also exhausted. The surface treatment of the substrate ends.

As shown in FIG. 1G, the driving gas of the valves V14 and V24 at the inlet of the waste gas line 3 is stopped, the valves V14 and V24 are closed, the tetramethylsilane Si (CH ₃ ) ₄ line of the gas supply system 1c and the gas supply system 1b. The driving gas is supplied to the carbon dioxide CO ₂ line and the triple valve 2b to open the valve, and the mixed gas is flowed into the reaction chamber RC to form a reduced pressure atmosphere of about 280 Pa. The temperature of the substrate SUB is set to about 400 ° C., and plasma is generated by turning on the high-frequency power source PS. A SiC layer is deposited. Note that the SiC layer is a layer made of a material containing Si—C bonds, and may contain other components (H, O, etc.) derived from the source gas.

  As shown in FIG. 1H, the high frequency power supply PS is turned off, all valves of the gas supply system pipes 1a, 1b, 1c and the triple valves 2a, 2b are closed, and the gas supply system 1b side valve at the inlet of the waste gas line 3 is closed. The driving gas is supplied to V24 to open the valve V24. Residual gas in the reaction chamber RC is exhausted, and residual gas on the downstream side of the gas supply system pipe 1b is also exhausted. The SiC layer deposition ends. Thereafter, an interlayer insulating film is formed.

FIG. 1I is a photograph showing a surface state obtained by photographing the surface of the SiC layer with an optical microscope. Many protrusions are observed, and it is considered that Si indicates abnormally grown hillocks. Since it is not observed when the surface treatment is not performed, it is considered that hillocks are generated by the soak with the SiH ₄ / NH ₃ mixed gas and the plasma treatment with the NH ₃ / N ₂ mixed gas.

  FIG. 1J is a graph showing the results of measuring the resistance of the copper wiring. The squares show the resistance distribution, and the horizontal line drawn in them shows the average value. Vertical lines on the top and bottom indicate the width of variation. Although some samples have a resistance value Rt that is less than the intended value, there are many samples that exceed the resistance value Rt, which is not a satisfactory result.

The inventor examined the cause of these unsatisfactory experimental results. One possibility is the interlocking triple valve 2a. After soaking with the SiH ₄ / NH ₃ mixed gas shown in FIG. 1C, the triple valve 2a is closed as shown in FIG. 1D. SiH ₄ gas is confined in the triple valve 2a. Since the piping between the triple valves V11, V12, V13 is as long as about 1.8 m, there is a volume that cannot be ignored. Since it is SiH ₄ gas before being diluted with NH ₃ gas, the concentration is also high.

In the process of FIG. 1E, the triple valves 2a and 2b are opened, N ₂ gas flows through the triple valve 2a, and NH ₃ gas flows through the triple valve 2b. Even if NH ₃ gas is confined in the triple valve 2b, no problem will occur because the same NH ₃ gas flows. N ₂ gas flows through the triple valve 2a, but there is no guarantee that the previously confined SiH ₄ gas will disappear quickly. In particular, SiH ₄ gas adsorbed on the surface or the like may be released over time. When copper in the copper wiring migrates due to heat generated by plasma, a fresh copper surface that is not covered by the nitrided Si layer may be generated. When SiH ₄ comes into contact with and reacts with the copper surface, Si may grow and hillocks may occur. If the substrate is heated in a process such as plasma treatment or SiC layer growth and there is Si adhering to the copper wiring, Si may diffuse into the copper wiring. Si diffusion into the copper interconnect will increase the resistance of the copper interconnect.

  Therefore, the present inventor has considered improving the PE-CVD apparatus so that gas is not trapped in the triple valve 2a. When discarding the residual gas downstream of the gas supply systems 1a and 1b by opening the valves V14 and V24 at the inlet of the waste gas line 3, only one of the three valves V11, V12 and V13 is closed in the triple valve 2a. If possible, the residual gas in the reaction chamber and the residual gas on the downstream side of the gas supply system can be exhausted, and the confinement of the gas in the triple valve 2a can be avoided.

  FIG. 2A is a diagram schematically showing the configuration of a prototype PE-CVD apparatus. The valve drive gas is all turned off. Replace one of the triple valves 2a, the second valve V12 in the prototype device, with a normally open valve (indicated by a circle), and close the gas supply line 3 on the gas supply system 1a side. The valve V14 is interlocked (the drive gas is made common). The first and third valves V11 and V13 of the triple valve 2a are interlocked with a normally closed valve, which is the same as that described with reference to FIG. 1C. Valves V11 and V13 are interlocking valves driven by the driving gas DG1, and valves V12 and V14 are interlocking valves driven by the driving gas DG2. However, when the driving gas DG2 is supplied, the valve V14 is opened and the valve V12 is closed. When the driving gases DG1 and DG2 are supplied, the triple valve 2a is closed only at V12, and V11 and V13 are opened. The valve V14 of the waste gas line is opened. When only the driving gas DG1 is supplied, all the triple valves 2a are opened, and the gas supply system 1a and the reaction chamber RC are connected. The valve V14 of the waste gas line is closed. The triple valve 2b is a normally closed valve that is not changed and the valves V21, V22, and V23 are all opened by supplying the driving gas. In the process of supplying gas from the gas supply systems 1a and 1b to the reaction chamber RC shown in FIGS. 1C and 1E, the driving gas is supplied to the triple valve 2b to be opened, and the interlocking valves V11 and V13 are driven. The same state is realized by supplying the gas DG1.

  FIG. 2B shows a state where the residual gas is discarded. The driving gas in the gas supply system 1 is stopped, all valves are closed, the driving gas supply to the triple valve 2b is also stopped, and the triple valves V21, V22, V23 are closed. Driving gas DG1, DG2 is supplied to the triple valve 2a. The driving gas DG1 opens the valves V11 and V13. The driving gas DG2 opens the valve V14 and closes the valve V12. Residual gas in the gas supply system 1a side pipe above the closed valve V12 is discarded from the gas line 3 through the valve V14, and residual gas in the reaction chamber RC in the pipe below the valve V12 is discharged from the reaction chamber. Exhausted. 1C to 1H, the residual gas exhausting step shown in FIGS. 1D and 1F is replaced with the one shown in FIG. 2B. It is expected that gas confinement in the triple valve 2a is suppressed, and adverse effects due to the confined gas are suppressed.

  FIG. 2C shows a state in which the gas supply system 1b side valve V24 at the inlet of the discarded gas line 3 shown in FIG. 1H is opened and the triple valve 2b is closed to exhaust. The valve V12 is normally open.

  When the steps of FIGS. 1C to 1H are completed and the reaction chamber RC is opened, all of the driving gas may be turned off to the state of FIG. 2A. The valve V12 is opened, but no problem arises because the valves V1 and V3 on both sides are closed. In order to close all the triple valves V11, V12, V13, the driving gas DG2 may be supplied.

  Using the prototype PE-CVD apparatus, the process shown in FIGS. 1C and 1H is replaced with FIG. 2B in FIGS. 1D and 1F, and FIG. 1H is replaced with FIG. 2C to perform surface treatment on the copper dual damascene wiring. Growing layer.

  FIG. 3A is an optical micrograph of the surface of the SiC layer, and FIG. 3B is a graph showing a measurement result of wiring resistance. No hillock-like surface irregularities were observed. Although the wiring resistance varies in some cases over the target wiring resistance Rt, the main distribution of the wiring resistance is lower than the target resistance value. The width of the variation has also narrowed. Apart from whether the inventor's interpretation was correct or not, as a result, the performance of the copper wiring was improved and the properties of the semiconductor device were also improved. This is thought to be due to the suppression of gas confinement.

  As mentioned above, although this invention was demonstrated along the preliminary experiment and the Example, these are not restrictive at all. For example, the triple valve 2b may have the same configuration as the triple valve 2a. The number of gas supply systems can be increased or decreased arbitrarily. The copper wiring includes not only pure copper but also a copper alloy. The barrier metal is not limited to TaN. Ta, TiN or the like may be used. The material of the interlayer insulating film is not limited to silicon oxide or SiOC. A coating type low dielectric constant insulating film such as porous silica or SiLK may be used. The copper diffusion preventing insulating film is not limited to the SiC film. A SiN film or the like may be used.

  The gas supply system and the reaction chamber may be connected by a double valve. It would be effective for a configuration without a filter. Further, four or more valves including a plurality of filters may be used. When pipes including two or more continuous valves are used and unnecessary gases are discarded, gas confinement occurs if the continuous valves are simultaneously closed. If only one of the continuous valves is closed, gas confinement can be suppressed. Similar effects can be expected from a high-frequency power source and a CVD apparatus without a counter electrode instead of the PE-CVD apparatus.

  It will be apparent to those skilled in the art that other various modifications, substitutions, improvements, combinations, and the like are possible. The features of the present invention will be described below.

[Appendix 1] (1)
A reaction chamber for film formation;
A first gas supply system pipe for supplying gas to the reaction chamber, the first gas supply system pipe including a plurality of pipes including a mass flow controller and valves before and after the mass flow controller;
A first connection pipe having a continuous valve including two or more valves connecting the first gas supply system pipe and the reaction chamber;
An exhaust pipe connected to the reaction chamber;
A waste gas pipe including a first waste gas valve that selectively connects the exhaust system pipe downstream with the first gas supply system pipe;
And one of the continuous valves of the first connection pipe and the first discarded gas valve are normally open, and the other is normally closed. Interlocking vapor phase growth equipment.

[Appendix 2] (2)
The vapor phase growth apparatus according to supplementary note 1, wherein when there are two or more valves other than the one valve of the continuous valve of the first connection pipe, they are of the same type and interlock with a common driving gas.

[Appendix 3] (3)
A second gas supply system pipe for supplying gas to the reaction chamber, the second gas supply system pipe including a plurality of pipes including a mass flow controller and valves before and after the mass flow controller;
A second connection pipe having a continuous valve including two or more valves connecting the second gas supply system pipe and the reaction chamber;
The vapor phase growth apparatus according to appendix 1 or 2, further comprising: a second waste gas valve that selectively connects the exhaust gas pipe downstream of the second gas supply system pipe and the exhaust system pipe.

[Appendix 4]
The vapor phase growth apparatus according to appendix 3, wherein the two or more valves of the second connection pipe are the same type of valves that are linked by a common driving gas.

[Appendix 5]
Valves before and after the mass flow controller of the first and second gas supply pipes, valves other than the one valve of the continuous valve of the first connection pipe, continuous valves of the second connection pipe, and the waste gas The vapor phase growth apparatus according to appendix 3 or 4, wherein the first and second discarded gas valves of the pipe are normally closed types, and the one valve of the continuous valve of the first connection pipe is a normally open type. .

[Appendix 6]
The continuous valves of the first and second connection pipes are first, second, and third triple valves, including a filter between the second and third valves, and the first and second valves are connected between the first and second valves. 2. The vapor phase growth apparatus according to any one of appendices 3 to 5, which is longer than between the third and third valves.

[Appendix 7]
The vapor phase growth apparatus according to any one of appendices 1 to 6, further comprising a high-frequency power source for generating plasma in the reaction chamber.

[Appendix 8] (4)
Preparing a semiconductor substrate on which damascene wiring is formed;
A reaction chamber, a first gas supply system pipe, a first connection pipe including two or more continuous valves connecting the first gas supply system pipe and the reaction chamber, and connected to the reaction chamber The semiconductor in the reaction chamber of a vapor phase growth apparatus having an exhaust system pipe, a waste gas pipe including a first waste gas valve that selectively connects the exhaust system pipe and a downstream of the first gas supply system pipe Carrying in a substrate and supplying a first gas from the first gas supply system pipe to perform a first surface treatment;
Closing the first gas supply system pipe, closing only one of the two or more continuous valves of the first connection pipe, and opening the first waste gas valve to exhaust residual gas;
Supplying a second gas from the first gas supply system piping to perform a second surface treatment;
A method of manufacturing a semiconductor device including:

[Appendix 9] (5)
The vapor phase growth apparatus further includes a second gas supply system pipe, and a second connection pipe including two or more continuous valves that connect the second gas supply system pipe and the reaction chamber, The waste gas pipe includes a second waste gas valve that selectively connects the exhaust gas pipe downstream with the second gas supply system pipe, and the first surface treatment and the second surface treatment include The method for manufacturing a semiconductor device according to appendix 8, wherein gas is supplied from a first gas supply system pipe and the second gas supply system pipe.

[Appendix 10]
The first surface treatment is performed by supplying SiH ₄ gas from the first gas supply system pipe and supplying a dilution gas from the second gas supply system pipe, and the second surface treatment is performed by the first surface treatment. The manufacturing method of a semiconductor device according to appendix 9, wherein dilution gas is supplied from the gas supply system pipe and NH ₃ is supplied from the second gas supply system pipe, and the process is performed in plasma.

[Appendix 11]
The damascene wiring is copper wiring;
After the second surface treatment, further includes a step of vapor-phase growing a copper diffusion prevention insulating film,
The method for manufacturing a semiconductor device according to any one of appendices 8 to 10.

[Appendix 12]
The method of manufacturing a semiconductor device according to claim 11, wherein the step of vapor-phase-growing the copper diffusion prevention insulating film forms the SiC film by plasma-enhanced chemical vapor deposition.

CDB1 first copper diffusion prevention insulating film,
IL1 first interlayer insulating film,
BM barrier metal layer,
CW copper layer,
DDW dual damascene wiring,
SP surface treatment,
CDB2 second copper diffusion prevention insulating film,
IL2 second interlayer insulating film,
V valve,
MFC mass flow controller,
RC reaction chamber,
VP vacuum exhaust system,
PS high frequency power supply,
DG driving gas,
1 gas supply system,
2 Triple valve,
3 Waste gas line,
11 Silicon substrate,
12 Shallow trench isolation,
13 Gate insulating film,
14 gate electrode,
17 side wall spacer,
18 source / drain regions,
20 Etch stopper film,
21 lower interlayer insulating film,
22 Tungsten plug,
29, 47 Copper diffusion prevention insulating film,
44 barrier metal layer,
45 Copper wiring layer.

Claims (4)

A reaction chamber for film formation;
A first gas supply system for supplying a first gas to the reaction chamber, the first gas supply system including a mass flow controller and a plurality of pipes including valves before and after the mass flow controller;
A first connection pipe connecting the first gas supply system and the reaction chamber;
A first continuous valve including two or more valves provided in the first connection pipe and capable of shutting off the supply of the first gas to the reaction chamber;
An exhaust pipe connected to the reaction chamber;
A waste gas pipe connected to the exhaust system pipe;
A first waste gas valve that controls connection and disconnection between the first connection pipe downstream of the first gas supply system and upstream of the first continuous valve and the waste gas pipe;
One valve of the first continuous valve and the first discarded gas valve are different types, one being normally open and the other being normally closed, and interlocked by the first driving gas, A vapor phase growth apparatus in which another valve of the first continuous valve is driven by a second driving gas.   2. The vapor phase growth apparatus according to claim 1, wherein two or more of the other valves of the first continuous valve are of the same type and are interlocked by the second driving gas. A second gas supply system for supplying a second gas to the reaction chamber, the second gas supply system including a mass flow controller and a plurality of pipes including valves before and after the mass flow controller;
A second connection pipe connecting the second gas supply system and the reaction chamber;
A second continuous valve including two or more valves provided in the second connection pipe and capable of shutting off the supply of the second gas to the reaction chamber;
A second waste gas valve capable of controlling connection and disconnection between the second connection pipe and the waste gas pipe downstream of the second gas supply system and upstream of the second continuous valve;
The vapor phase growth apparatus according to claim 1 or 2, further comprising: Preparing a semiconductor substrate on which damascene wiring is formed;
A first gas supply system that includes a reaction chamber and a first gas supply system that supplies a first gas to the reaction chamber, the gas flow system including a mass flow controller and a plurality of pipes provided before and after the mass flow controller;
A first connection pipe connecting the first gas supply system and the reaction chamber;
Provided in the first connection pipe;
A first continuous valve including two or more valves capable of shutting off the supply of the first gas to the reaction chamber;
An exhaust pipe connected to the reaction chamber;
A waste gas pipe connected to the exhaust system pipe;
A first waste gas valve that controls connection and disconnection between the first connection pipe downstream of the first gas supply system and upstream of the first continuous valve and the waste gas pipe;
One valve of the first continuous valve and the first waste gas valve are different types, one being normally open and the other being normally closed, and interlocked by the first driving gas,
Carrying the semiconductor substrate into the reaction chamber of a vapor phase growth apparatus in which another valve of the first continuous valve is driven by a second driving gas;
Supplying a first process gas as the first gas from the first gas supply system to perform a first surface treatment;
Closing the first gas supply system;
Close only one valve of the first continuous valve;
Opening the first waste gas valve to exhaust residual gas;
Supplying a second processing gas as the first gas from the first gas supply system to perform a second surface treatment;
A method of manufacturing a semiconductor device including:

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