JP2011187757A - Method of manufacturing semiconductor device, and substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing semiconductor device, along with a substrate processing apparatus, capable of efficiently vaporizing a liquid raw material supplied into a processing chamber. <P>SOLUTION: The method of manufacturing semiconductor device includes: a step of loading a wafer 14 into the processing chamber 16; a step of forming a metal-containing film having a predetermined film thickness on the wafer 14 by alternately repeating a step of applying a bias voltage to a liquid raw material spray nozzle 70 and a supporting base 18 while supplying the liquid raw material including a metal compound into the processing chamber 16 through the liquid raw material spray nozzle 70 so as to spray a raw material gas, which is obtained by vaporizing the liquid raw material, onto the wafer 14 in a charged state, thereby allowing the raw material gas to adsorb onto the wafer 14, and a step of supplying an oxidizer into the processing chamber 16 so that the raw material gas adsorbing on the wafer 14 reacts with the oxidizer to form a metal-containing layer; and a step of unloading the treated wafer 14 from the processing chamber 16. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus.

As an insulating film material of a DRAM (Dynamic Random Access Memory) capacitor, Ta ₂ O ₅ and Al ₂ O ₃ etc. in the 90 nm generation, HfO ₂ , ZrO ₂ , Al ₂ O ₃ etc. in the 65 nm generation, SrTiO ₃ etc. in the 45 nm generation and later TiO _{2 and the} like are listed as candidates.

The Al film forming raw material of Al ₂ O ₃ is trimethylaluminum (Al (CH ₃ ) ₃ ), aluminum chloride (AlCl ₃ ) or the like, and the vapor pressure of AlCl ₃ (1.2 kPa at 20 ° C.) is relatively high.
On the other hand, the Hf film forming raw material of HfO ₂ is tetrakisethylmethylaminohafnium (TEMAH: Hf [N (C ₂ H ₅ ) (CH ₃ )] ₄ ) or tetrakisdimethylaminohafnium (TDMAH, Hf [N (CH ₃ ) ₂ ] ₄ ) etc., and the vapor pressure of TEMAH (13 Pa at 57 ° C.) is lower than that of AlCl ₃ .
The SrTiO ₃ raw material for Sr film formation is [1- (2-methoxyethoxy) -2,2,6,6-tetramethyl-3,5-heptaneedionate] stronnium (Sr (METHD) ₂ ). And Sr (tmhd) ₄ complex, etc., and the vapor pressure (4.6 Pa at 200 ° C.) of Sr (METHD) ₂ is lower than that of AlCl ₃ or TEMAH.

Conventionally, a vaporization method in which the film forming raw material as described above is vaporized using a vaporizer and supplied to a reaction chamber has been adopted. However, the vaporization method has a problem that a sufficient amount of vaporization cannot be obtained, or the raw material is liquefied in the middle of the piping and the piping is clogged.
In view of this, a method for supplying a film forming raw material by a flash spray method has been proposed.

  Patent Document 1 discloses a configuration in which a mixed solution in which a low-boiling organic compound is mixed with a solid or liquid organometallic compound at room temperature is directly injected by an injection valve into a film forming chamber that holds a substrate inside. .

JP 2008-182183 A

However, the above method has a problem that a sufficient vaporization amount cannot be obtained for a material having a lower vapor pressure (for example, Sr (METHD) ₂ ) than a film forming raw material handled by a conventional vaporizer. It was.

  An object of the present invention is to provide a method of manufacturing a semiconductor device and a substrate processing apparatus that efficiently vaporize a liquid material supplied to a processing chamber.

  According to one aspect of the present invention, a bias voltage is applied between the spray nozzle and the substrate while the substrate is loaded into the processing container, and the first raw material containing the metal compound is supplied from the spray nozzle into the processing container. The first raw material is sprayed in a charged state and supplied to the substrate, and the first raw material is adsorbed on the substrate, and the second raw material is placed in the processing container. A predetermined film on the substrate by alternately repeating the step of forming the metal-containing layer by reacting the first raw material and the second raw material adsorbed on the substrate. There is provided a method for manufacturing a semiconductor device, comprising: a step of performing a process of forming a thick metal-containing film; and a step of carrying out a processed substrate from the processing container.

  According to another aspect of the present invention, a processing container for accommodating a substrate, a first raw material supply system for supplying a first raw material containing a metal compound from a spray nozzle into the processing container, and a first container in the processing container. A second raw material supply system for supplying two raw materials, a bias voltage applying mechanism for applying a bias voltage between the spray nozzle and the substrate, and supplying the first raw material from the spray nozzle into the processing container. By applying a bias voltage between the spray nozzle and the substrate, the first raw material is sprayed in a charged state, supplied to the substrate, the first raw material is adsorbed on the substrate, and the processing is performed. By supplying the second raw material into the container, the first raw material adsorbed on the substrate reacts with the second raw material to form a metal-containing layer, and this is alternately repeated. On the substrate A substrate process comprising: a first raw material supply system, a second raw material supply system, and a control unit that controls the bias voltage application mechanism so as to form a metal-containing film having a predetermined thickness. An apparatus is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method and substrate processing apparatus of a semiconductor device which can vaporize the liquid raw material supplied to a processing chamber efficiently can be provided.

It is a section lineblock diagram at the time of substrate processing of a substrate processing device used for one embodiment of the present invention. It is a section lineblock diagram at the time of substrate conveyance of a substrate processing device used for one embodiment of the present invention. It is a block diagram around the processing container of the substrate processing apparatus used for one Embodiment of this invention. It is a figure which shows the formation flow of a hafnium oxide film | membrane. It is a figure which shows the supply timing of a raw material, an oxidizing agent, and purge gas.

(1) Configuration of Substrate Processing Apparatus A configuration of a substrate processing apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional configuration diagram of the substrate processing apparatus according to the present embodiment during wafer processing, and FIG. 2 is a cross-sectional configuration diagram of the substrate processing apparatus according to the present embodiment during wafer transfer.

<Processing chamber>
As shown in FIGS. 1 and 2, the substrate processing apparatus according to this embodiment includes a processing container 12. The processing container 12 is configured as a flat sealed container having a circular cross section, for example. Moreover, the processing container 12 is comprised by metal materials, such as aluminum (Al) and stainless steel (SUS), for example. A processing chamber 16 for processing a wafer 14 as a substrate is configured in the processing container 12.

A support base 18 that supports the wafer 14 is provided in the processing chamber 16. For example, quartz (SiO ₂ ), carbon, ceramics, silicon carbide (SiC), aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), or the like is formed on the upper surface of the support base 18 that the wafer 14 directly touches. A susceptor 20 is provided as a support plate. In addition, the support base 18 incorporates a heater 22 as a heating means for heating the wafer 14. The lower end portion of the support base 18 passes through the bottom portion of the processing container 12.

  An elevating mechanism 24 is provided outside the processing chamber 16. By operating the lifting mechanism 24, the wafer 14 supported on the susceptor 20 can be lifted and lowered. The support table 18 rises to the position shown in FIG. 1 (wafer processing position) when the wafer 14 is processed, and descends to the position shown in FIG. 2 (wafer transfer position) when the wafer 14 is transferred. The periphery of the lower end portion of the support base 18 is covered with a bellows 26, and the inside of the processing chamber 16 is kept airtight.

  Further, for example, three lift pins 28 are provided in the vertical direction on the bottom surface (floor surface) of the processing chamber 16. The support base 18 is provided with through holes 30 for allowing the lift pins 28 to pass therethrough at positions corresponding to the lift pins 28. When the support table 18 is lowered to the wafer transfer position, the upper end portion of the lift pins 28 protrudes from the upper surface of the support table 18 so that the lift pins 28 support the wafer 14 from below.

  When the support table 18 is raised to the wafer processing position, the lift pins 28 are buried from the upper surface of the support table 18 so that the susceptor 20 provided on the upper surface of the support table 18 supports the wafer 14 from below. In addition, since the lift pins 28 are in direct contact with the wafer 14, it is desirable to form the lift pins 28 from a material such as quartz or alumina.

<Wafer transfer port>
On the inner wall side surface of the processing chamber 16, a wafer transfer port 32 for transferring the wafer 14 into and out of the processing chamber 16 is provided. The wafer transfer port 32 is provided with a gate valve 34. By opening the gate valve 34, the processing chamber 16 and the transfer chamber (preliminary chamber) 36 are communicated with each other. The transfer chamber 36 is formed in a sealed container 39, and a transfer robot 38 for transferring the wafer 14 is provided in the transfer chamber 36.

  The transfer robot 38 is provided with a transfer arm 38 a that supports the wafer 14 when the wafer 14 is transferred. By opening the gate valve 34 with the support 18 lowered to the wafer transfer position, the transfer robot 38 can transfer the wafer 14 between the processing chamber 16 and the transfer chamber 36. It is configured. The wafer 14 transferred into the processing chamber 16 is temporarily placed on the lift pins 28 as described above.

<Exhaust system>
An exhaust port 40 for exhausting the atmosphere in the processing chamber 16 is provided on the inner wall side surface of the processing chamber 16 and on the side opposite to the wafer transfer port 32. An exhaust pipe 42 is connected to the exhaust port 40. The exhaust pipe 42 includes a pressure regulator 44 such as an APC (Auto Pressure Controller) that controls the inside of the processing chamber 16 to a predetermined pressure, a raw material recovery trap 46, and A vacuum pump 48 is connected in series in order. An exhaust system (exhaust line) is mainly configured by the exhaust port 40, the exhaust pipe 42, the pressure regulator 44, the raw material recovery trap 46, and the vacuum pump 48.

<Film forming material introduction system>
On the upper surface (ceiling wall) of the processing chamber 16, a liquid source spray nozzle 70 that supplies “source gas”, which is vaporized by low pressure boiling by spraying (spraying) the liquid source, into the processing chamber 16; A liquid oxidant spray nozzle 72 that supplies “oxidant gas”, which is vaporized by boiling under reduced pressure by injecting liquid oxidant, into the processing chamber 16, and gaseous oxidant into the processing chamber 16. A gas oxidant introduction port 74 to be supplied and a purge gas introduction port 76 to supply a purge gas into the processing chamber 16 are provided. Hereinafter, these (the liquid material spray nozzle 70, the liquid oxidant spray nozzle 72, the gas oxidant introduction port 74, and the purge gas introduction port 76) may be collectively referred to as a film forming material introduction system.
In FIG. 1 and FIG. 2, for the sake of simplification, the spray nozzle (the liquid raw material spray nozzle 70 and the liquid oxidant spray nozzle 72) and the introduction port (the gas oxidant introduction port 74 and the purge gas introduction port 76) are respectively shown. One by one is shown.
The configuration of the liquid and gas supply system connected to these film forming material introduction systems will be described later.

<Shower head>
A shower head 52 as a gas dispersion mechanism is provided between the film forming material introduction system and the wafer 14 at the wafer processing position. The shower head 52 disperses the gas introduced from the film forming material introduction system, and the gas that has passed through the dispersion plate 52a is further uniformly dispersed and supplied to the surface of the wafer 14 on the support base 18. A shower plate 52b. The dispersion plate 52a and the shower plate 52b are provided with a plurality of vent holes.

  The dispersion plate 52 a is disposed to face the upper surface of the shower head 52 and the shower plate 52 b, and the shower plate 52 b is disposed to face the wafer 14 on the support base 18. Note that spaces are respectively provided between the upper surface of the shower head 52 and the dispersion plate 52a, and between the dispersion plate 52a and the shower plate 52b, and these spaces are supplied from the film forming material introduction system. It functions as a dispersion chamber (first buffer space) 52c for dispersing the gas and a second buffer space 52d for diffusing the gas that has passed through the dispersion plate 52a.

<Exhaust duct>
A step portion 54 is provided on the inner wall side surface of the processing chamber 16. The step portion 54 is configured to hold the conductance plate 56 near the wafer processing position. The conductance plate 56 is configured as a single donut-shaped (ring-shaped) disk in which a hole for accommodating the wafer 14 is provided in the inner peripheral portion.

  A plurality of outlets 58 arranged in the circumferential direction at predetermined intervals are provided on the outer periphery of the conductance plate 56. The discharge port 58 is formed discontinuously so that the outer periphery of the conductance plate 56 can support the inner periphery of the conductance plate 56.

  On the other hand, a lower plate 60 is locked to the outer peripheral portion of the support base 18. The lower plate 60 includes a ring-shaped concave portion 60a and a flange portion 60b provided integrally on the inner upper portion of the concave portion 60a. The recess 60 a is provided so as to close a gap between the outer peripheral portion of the support base 18 and the inner wall side surface of the processing chamber 16.

  A part of the bottom of the recess 60a near the exhaust port 40 is provided with a plate exhaust port 60c for exhausting (circulating) gas from the recess 60a to the exhaust port 40 side. The flange portion 60 b functions as a locking portion that locks on the upper outer peripheral edge of the support base 18. When the flange portion 60 b is locked on the upper outer peripheral edge of the support base 18, the lower plate 60 is moved up and down together with the support base 18 as the support base 18 moves up and down.

  When the support base 18 is raised to the wafer processing position, the lower plate 60 is also raised to the wafer processing position. As a result, the conductance plate 56 held in the vicinity of the wafer processing position closes the upper surface portion of the recess 60a of the lower plate 60, and the exhaust duct 62 is formed with the inside of the recess 60a as the gas flow path region. .

  At this time, due to the exhaust duct 62 (conductance plate 56, lower plate 60) and the support base 18, the inside of the processing chamber 16 is located above the processing chamber above the exhaust duct 62 and below the processing chamber below the exhaust duct 62. It will be partitioned. The conductance plate 56 and the lower plate 60 are made of a material that can be maintained at a high temperature, for example, high temperature resistant high load quartz, in consideration of etching of reaction products deposited on the inner wall of the exhaust duct 62. Is preferred.

  Here, the flow of gas in the processing chamber 16 during wafer processing will be described. First, the gas supplied from the film forming material introduction system to the upper portion of the shower head 52 enters the second buffer space 52d from the many holes of the dispersion plate 52a through the dispersion chamber (first buffer space) 52c. It passes through a large number of holes in the shower plate 52 b and is supplied into the processing chamber 16 and is uniformly supplied onto the wafer 14.

  The gas supplied onto the wafer 14 flows radially outward in the radial direction of the wafer 14. The surplus gas after contacting the wafer 14 flows radially on the exhaust duct 62 (that is, on the conductance plate 56) provided on the outer periphery of the support base 18 toward the radially outer side of the wafer 14. The gas is discharged from a discharge port 58 provided on the duct 62 into the gas flow path region (in the recess 60a) in the exhaust duct 62.

  Thereafter, the gas flows in the exhaust duct 62 and is exhausted to the exhaust port 40 via the plate exhaust port 60c. As described above, gas sneaking into the lower portion of the processing chamber 16, that is, the back surface of the support base 18 and the bottom surface side of the processing chamber 16 is suppressed.

Next, the configuration around the processing container 12 and the configuration of the liquid / gas supply system connected to the film forming material introduction system will be described with reference to FIG.
FIG. 3 is a configuration diagram around the processing container 12 of the substrate processing apparatus according to the embodiment of the present invention.

<Power supply>
A spray power source 80 that applies a bias voltage to the liquid source spray nozzle 70 is connected to the liquid source spray nozzle 70. For this reason, the raw material gas injected from the liquid raw material spray nozzle 70 is supplied into the processing chamber 16 in a charged state. Since the charged source gas (source molecule) repels each other, the molecules diffuse into the processing chamber 16 without bonding and clustering, for example.

  Similarly, a spray power source 82 that applies a bias voltage to the liquid oxidant spray nozzle 72 is connected to the liquid oxidant spray nozzle 72. For this reason, the oxidant gas sprayed from the liquid oxidant spray nozzle 72 is supplied into the processing chamber 16 in a charged state. Since the charged oxidant gas (oxidant molecule) repels each other, for example, the respective molecules are diffused into the processing chamber 16 without being clustered or the like.

  On the other hand, a support base power supply 84 that applies a bias voltage to the support base 18 is connected to the support base 18 that supports the wafer 14. By applying a bias voltage opposite to the bias voltage applied to the liquid material spray nozzle 70 and the liquid oxidant spray nozzle 72 by the spray power sources 80 and 82 to the support table 18 on the wafer 14 side, The raw material gas and the oxidant gas injected from the raw material spray nozzle 70 and the liquid oxidant spray nozzle 72 are accelerated and collide with the wafer 14.

  That is, the injected source gas and oxidant gas are accelerated according to the bias voltage between the injection side and the wafer 14 side. For this reason, the injected gas molecules (raw material gas and oxidant gas) are charged, ionized, diffused into the processing chamber 16 and simultaneously drawn into the wafer 14 side. Thereby, compared with the case where this configuration is not provided, the liquid source and the liquid oxidant are easily vaporized, and the amount of the source gas and the oxidant gas adsorbed on the wafer 14 can be increased. .

<Liquid material supply system>
A liquid source supply source 100 that supplies a liquid source including, for example, TEMAH (Hf source) as a source is provided outside the processing chamber 16. The liquid source supply source 100 is configured as a tank (sealed container) capable of containing (filling) the liquid source therein.

A pressurized gas supply pipe 102 is connected to the liquid source supply source 100. A pressurized gas supply source (not shown) is connected to the upstream end of the pressurized gas supply pipe 102. The downstream end of the pressurized gas supply pipe 102 communicates with a space existing in the upper part of the liquid source supply source 100, and the pressurized gas is supplied into this space.
As the pressurized gas, it is preferable to use a gas that does not react with the liquid material, for example, nitrogen (N ₂₎ an inert gas or the like is preferably used.

  A liquid source supply pipe 104 is connected to the liquid source supply source 100. The upstream end of the liquid source supply pipe 104 is immersed in the liquid source accommodated in the liquid source supply source 100.

  The downstream end of the liquid source supply pipe 104 is connected to the liquid source spray nozzle 70. The liquid source supply pipe 104 is provided with a liquid flow rate controller (LMFC) 106 as flow rate control means for controlling the supply rate of the liquid source, and an open / close valve V1 for controlling the supply of the liquid source.

  In the above configuration, the liquid source can be pumped (supplied) from the liquid source supply source 100 to the liquid source spray nozzle 70 by opening the open / close valve V1 and supplying the pumped gas from the pumped gas supply pipe 102. Become.

  A liquid source supply system (liquid source supply line) is mainly configured by the liquid source supply source 100, the pressurized gas supply pipe 102, the liquid source supply pipe 104, the LMFC 106, and the valve V1.

<Liquid oxidant supply system>
Similarly, a liquid oxidant supply source 110 that supplies a liquid oxidant containing, for example, H ₂ O (water) as an oxidant is provided outside the processing chamber 16. The liquid oxidant supply source 110 is configured as a tank (sealed container) capable of containing (filling) the liquid oxidant therein.

A pressurized gas supply pipe 112 is connected to the liquid oxidant supply source 110. A pressurized gas supply source (not shown) is connected to the upstream end of the pressurized gas supply pipe 112. Further, the downstream side end portion of the pressurized gas supply pipe 112 communicates with a space existing in the upper part in the liquid oxidant supply source 110, and the pressurized gas is supplied into this space.
As the pressurized gas, it is preferable to use a gas that does not react with the liquid oxidizing agent, for example an inert gas such as N ₂ gas is preferably used.

  A liquid oxidant supply pipe 114 is connected to the liquid oxidant supply source 110. The upstream end of the liquid oxidant supply pipe 114 is immersed in the liquid oxidant accommodated in the liquid oxidant supply source 110.

  The downstream end of the liquid oxidant supply pipe 114 is connected to the liquid oxidant spray nozzle 72. The liquid oxidant supply pipe 114 is provided with a liquid flow rate controller (LMFC) 116 as flow rate control means for controlling the supply flow rate of the liquid oxidant, and an open / close valve V2 for controlling the supply of the liquid oxidant. .

  In the above configuration, the liquid oxidant is pumped (supplied) from the liquid oxidant supply source 110 to the liquid oxidant spray nozzle 72 by opening the opening / closing valve V2 and supplying the pumped gas from the pumped gas supply pipe 112. Is possible.

A liquid oxidant supply system (liquid oxidant supply line) is mainly configured by the liquid oxidant supply source 110, the pressurized gas supply pipe 112, the liquid oxidant supply pipe 114, the LMFC 116, and the valve V2.
<Gas oxidizing agent supply system>
A gas oxidant supply source 120 that supplies oxygen (O ₂ ) gas is provided outside the processing chamber 16. An upstream end of the first gas oxidant supply pipe 122 is connected to the gas oxidant supply source 120. An ozonizer 124 is connected to the downstream end of the first gas oxidant supply pipe 122 to generate a reaction gas (reactant), that is, an ozone gas as an oxidant, from oxygen gas by plasma. The first gas oxidant supply pipe 122 is provided with a flow rate controller (MFC) 126 as flow rate control means for controlling the supply flow rate of oxygen gas.

  An upstream end of an ozone gas supply pipe 130 as a gas oxidant supply pipe is connected to an ozone gas supply port 128 as an outlet of the ozonizer 124. The downstream end of the ozone gas supply pipe 130 is connected to the gas oxidant introduction port 74. That is, the ozone gas supply pipe 130 is configured to supply ozone gas as a gaseous oxidant into the processing chamber 16. The ozone gas supply pipe 130 is provided with an open / close valve V <b> 3 that controls supply of ozone gas into the processing chamber 16.

  An upstream end of the second gas oxidant supply pipe 132 is connected to the upstream side of the first gas oxidant supply pipe 122 from the MFC 126. The downstream end of the second gas oxidant supply pipe 132 is connected to the upstream side of the open / close valve V <b> 3 of the ozone gas supply pipe 130. The second gas oxidant supply pipe 132 is provided with a flow rate controller (MFC) 136 as flow rate control means for controlling the supply flow rate of oxygen gas.

  In the above-described configuration, oxygen gas is supplied to the ozonizer 124 to generate ozone gas, and ozone gas can be supplied into the processing chamber 16 by opening the opening / closing valve V3. If oxygen gas is supplied from the second gas oxidant supply pipe 132 during the supply of ozone gas into the processing chamber 16, the ozone gas supplied into the processing chamber 16 is diluted with oxygen gas, and the ozone gas is supplied. The density can be adjusted.

  Mainly, a gas oxidant supply system (first gas oxidant supply pipe 122, ozonizer 124, MFC 126, ozone gas supply pipe 130, open / close valve V3, second gas oxidant supply pipe 132, MFC 136 is used as a gas oxidant supply system ( Gas oxidant supply line).

<Purge gas supply system>
In addition, a purge gas supply source 140 for supplying N ₂ gas as a purge gas is provided outside the processing chamber 16. The purge gas supply source 140 is connected to an upstream end portion of the purge gas supply pipe 142. The purge gas supply pipe 142 is provided with a flow rate controller (MFC) 146 as flow rate control means for controlling the supply flow rate of the purge gas. The downstream end of the purge gas supply pipe 142 is connected to the purge gas inlet 76. That is, the purge gas supply pipe 142 is configured to supply N ₂ gas as a purge gas into the processing chamber 16. The purge gas supply pipe 142 is provided with an open / close valve V4 that controls the supply of N ₂ gas into the processing chamber 16.

  A purge gas supply system (purge gas supply line) is mainly configured by the purge gas supply source 140, the purge gas supply pipe 142, the MFC 146, and the open / close valve V4.

<Controller>
The substrate processing apparatus according to the present embodiment includes a controller 150 that controls the operation of each unit of the substrate processing apparatus. The controller 150 includes a heater 22, an elevating mechanism 24, a gate valve 34, a transfer robot 38, a pressure regulator (APC) 44, a vacuum pump 48, LMFCs 106 and 116, an ozonizer 124, MFCs 126, 136 and 146, open / close valves V1 to V4, and the like. To control the operation.

(2) Substrate Processing Step Next, as a step of manufacturing the semiconductor device (device) according to the embodiment of the present invention, a substrate processing step of forming a thin film on the wafer 14 using the above-described substrate processing apparatus. This will be described with reference to FIG.
FIG. 4 is a flowchart of the substrate processing process according to the embodiment of the present invention.
Hereinafter, a case where a hafnium oxide (HfO ₂ ) film is formed on the wafer 14 using ozone (O ₃ ) as an oxidizing agent will be described as an example. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 150.

<Substrate Loading Step (S1), Substrate Placement Step (S2)>
First, the elevating mechanism 24 is operated to lower the support base 18 to the wafer transfer position shown in FIG. Then, the gate valve 34 is opened to allow the processing chamber 16 and the transfer chamber 36 to communicate with each other. Then, the wafer 14 to be processed is loaded from the transfer chamber 36 into the processing chamber 16 with the transfer robot 38 supported by the transfer arm 38a (S1). The wafer 14 carried into the processing chamber 16 is temporarily placed on lift pins 28 protruding from the upper surface of the support base 18. When the transfer arm 38a of the transfer robot 38 returns from the processing chamber 16 to the transfer chamber 36, the gate valve 34 is closed.

  Subsequently, the elevating mechanism 24 is operated to raise the support base 18 to the wafer processing position shown in FIG. As a result, the lift pins 28 are buried from the upper surface of the support table 18, and the wafer 14 is placed on the susceptor 20 on the upper surface of the support table 18 (S2).

<Pressure adjusting step (S3), temperature raising step (S4)>
Subsequently, the pressure regulator (APC) 44 performs control so that the pressure in the processing chamber 16 becomes a predetermined processing pressure (S3). Further, the power supplied to the heater 22 is adjusted, the temperature of the wafer 14 is raised, and the surface temperature of the wafer 14 is controlled to be a predetermined processing temperature (S4).

In the substrate loading step (S1), the substrate placement step (S2), the pressure adjustment step (S3), the temperature raising step (S4), and the substrate unloading step (S10) described later, while operating the vacuum pump 48, The on-off valve V3 is closed, the on-off valve V4 is opened, and N ₂ gas is always allowed to flow into the processing chamber 16. Thereby, it is possible to suppress adhesion of particles on the wafer 14. The vacuum pump 48 is always operated at least from the substrate carry-in process (S1) to the substrate carry-out process (S10) described later.

<Raw material gas supply step (S5)>
Subsequently, the opening / closing valve V1 is opened, the liquid material is supplied to the liquid material spray nozzle 70, and introduction of the material gas into the processing chamber 16 is started. Here, the liquid raw material is a mixed solution of an organic metal compound raw material and a low boiling point organic compound.
In this embodiment, as the organometallic compound raw material (Hf raw material), for example, TEMAH (tetrakisethylmethylaminohafnium, Hf [N (C ₂ H ₅ ) (CH ₃ )] ₄ ), tetrakis (1-methoxy-2) -Methyl-2-propoxy) hafnium (Hf (MMP) ₄ , Hf [OC (CH ₃ ) ₂ CH ₂ OCH ₃ ] ₄ ), tetraxylary sutralium hafnium (Hf [OC (CH ₃ ) ₃ ] ₄ ), Use TDMAH (tetrakisdimethylaminohafnium, Hf [N (CH ₃ ) ₂ ] ₄ ), TDEAH (tetrakisdiethylaminohafnium, Hf [N (C ₂ H ₅ ) ₂ ] ₄ ), hafnium tetrachloride (HfCl ₄ ), etc. can do.

As a low boiling point organic compound, for example, n-pentane (CH ₃ (CH ₂ ) ₃ CH ₃ ), cyclopentane (C ₅ H ₁₀ ), hexane (CH ₃ (CH ₂ ) ₄ CH ₃ ), ethanol (C ₂ H) ₅ OH) and the like.
The low boiling point organic compound has a boiling point lower than that of at least the organometallic compound raw material.

When the source gas is introduced into the processing chamber 16, a bias voltage is applied to the liquid source spray nozzle 70 by the spray power source 80. A bias voltage opposite to the bias voltage applied to the liquid source spray nozzle 70 is applied to the support table 18 by a support table power supply 84. For this reason, the source gas sprayed from the liquid source spray nozzle 70 is charged and ionized to diffuse into the processing chamber 16, and is accelerated to collide with the wafer 14. At this time, the source gas is dispersed by the shower head 52 and uniformly supplied onto the wafer 14 in the processing chamber 16.
Excess source gas flows through the exhaust duct 62 and is exhausted to the exhaust port 40.

  When a predetermined time has elapsed after opening the on-off valve V1 and starting the supply of the source gas, the on-off valve V1 is closed and the supply of the source gas into the processing chamber 16 is stopped.

<Purge process (S6)>
After closing the on-off valve V1 and stopping the supply of the source gas into the processing chamber 16, the on-off valve V4 is opened to supply N ₂ gas into the processing chamber 16. N ₂ gas is supplied into the processing chamber 16 through the shower head 52, flows through the exhaust duct 62, and is exhausted to the exhaust port 40. In this way, the inside of the processing chamber 16 is purged with N ₂ gas, and the raw material gas remaining in the processing chamber 16 is removed.

<Oxidant supply step (S7)>
Oxygen gas is supplied from the gaseous oxidant supply source 120 to the ozonizer 124, and ozone gas is generated by the ozonizer 124. When the purge in the processing chamber 16 is completed, the opening / closing valve V4 is closed and the opening / closing valve V3 is opened, and supply of ozone gas as an oxidizing agent into the processing chamber 16 from the gas oxidizing agent inlet 74 is started. The ozone gas is dispersed by the shower head 52 and is uniformly supplied onto the wafer 14 in the processing chamber 16. Excess ozone gas and reaction byproducts flow through the exhaust duct 62 and are exhausted to the exhaust port 40.

  When a predetermined time has elapsed after opening the on-off valve V3 and starting the supply of ozone gas, the on-off valve V3 is closed and the supply of ozone gas into the processing chamber 16 is stopped.

<Purge process (S8)>
After closing the on-off valve V3 and stopping the supply of ozone gas into the processing chamber 16, the on-off valve 4 is opened to supply N ₂ gas into the processing chamber 16. N ₂ gas is supplied into the processing chamber 16 through the shower head 52, flows through the exhaust duct 62, and is exhausted to the exhaust port 40. In this way, the inside of the processing chamber 16 is purged with N ₂ gas, and ozone gas and reaction byproducts remaining in the processing chamber 16 are removed.

<Repeating step (S9)>
Then, the steps S5 to S8 are set as one cycle, and this cycle is repeated a predetermined number of times, whereby a HfO ₂ film having a desired film thickness is formed on the wafer 14 (thin film forming step).
FIG. 5 is a diagram illustrating the supply timing of the raw material, the oxidizing agent, and the purge gas in steps S5 to S8. Thus, the source gas (TEMAH) and the oxidant gas (O ₃ ) are not supplied into the processing chamber 16 at the same time, and the processing chamber is formed by the purge gas (N ₂ ) between the steps S5 and S7. A process of purging the inside of the 16 is sandwiched.

<Substrate unloading step (S10)>
Thereafter, the wafer 14 after the HfO ₂ film having a desired film thickness is formed from the inside of the processing chamber 16 by a procedure reverse to the procedure shown in the substrate loading step (S1) and the substrate placement step (S2). It is carried out into the transfer chamber 36, and the substrate processing process concerning this embodiment is completed.

  In the case where the thin film forming step is performed by the CVD method, the processing temperature is controlled so as to be a temperature range in which the source gas is self-decomposed. In this case, in the source gas supply step (S 5), the source gas is self-decomposed and a thin film of about 1 to several tens of atomic layers is formed on the wafer 14. In the oxidant supply step, impurities such as C and H are removed from a thin film of about 1 to several tens of atomic layers formed on the wafer 14 by ozone gas.

  Further, when the thin film forming process is performed by the ALD method, the processing temperature is controlled so as to be a temperature range in which the source gas is not self-decomposed. In this case, the source gas is adsorbed onto the wafer 14 in the source gas supply step. In the oxidant supply step, the raw material gas adsorbed on the wafer 14 and the ozone gas react to form a thin film having a thickness of less than one atomic layer on the wafer 14. At this time, impurities such as C and H to be mixed into the thin film can be desorbed by ozone gas.

For example, when forming a HfO ₂ film, the processing temperature is 390 to 450 ° C., the processing pressure is 50 to 400 Pa, and the organic material is processed in the processing furnace of the present embodiment by the CVD method. Metal compound raw material (TEMAH) supply flow rate: 0.01 to 0.2 g / min, oxidizing agent (ozone gas) supply flow rate: 100 to 3000 sccm are exemplified.

In the processing furnace of the present embodiment, the processing conditions for processing the substrate by the ALD method are, for example, when forming an HfO ₂ film, processing temperature: 200 to 350 ° C., processing pressure: 50 to 400 Pa, organic Metal compound raw material (TEMAH) supply flow rate: 0.01 to 0.2 g / min, oxidizing agent (ozone gas) supply flow rate: 100 to 3000 sccm are exemplified.

In the above embodiment, the case where gaseous ozone gas is used as the oxidant has been described. However, the present invention is not limited thereto, and liquid H ₂ O may be used as the oxidant. In this case, H ₂ O as an oxidant is supplied from the liquid oxidant spray nozzle 72 into the processing chamber 16 instead of the gas oxidant introduction port 74.

When a zirconium oxide (ZrO ₂ ) film is formed on the wafer 14, examples of the organometallic compound raw material (Zr raw material) include tetrakisdimethylaminozirconium (Zr [N (CH ₃ ) ₂ ] ₄ ), tetrakisdiethylamino Zirconium (Zr [N (C ₂ H ₅ ) ₂ ] ₄ ), tetrakisethylmethylamino zirconium (Zr [N (C ₂ H ₅ ) (CH ₃ )] ₄ ) and the like can be used.

When forming a strontium titanate (SrTiO ₃ ) film on the wafer 14, as the organometallic compound raw material (Sr raw material), for example, bis [1- (2-methoxyethoxy) -2,2,6,6-tetra Methyl-3,5-heptaneedionate] stronium (Sr (METHD) ₂ ), bis (pentamethylcyclopentadienyl) strontium (Sr [C ₅ (CH ₃ ) ₅ ] ₂ ), etc. it can.

  In the above embodiment, the substrate processing apparatus having the configuration in which the shower head 52 is provided has been described. However, the present invention is not limited thereto, and the substrate processing apparatus may be configured to have no shower head 52. Further, a rotation mechanism for rotating the support base 18 may be provided.

[Preferred embodiment of the present invention]
Hereinafter, other preferred embodiments of the present invention will be additionally described.

  According to one aspect of the present invention, a bias voltage is applied between the spray nozzle and the substrate while the substrate is loaded into the processing container, and the first raw material containing the metal compound is supplied from the spray nozzle into the processing container. The first raw material is sprayed in a charged state and supplied to the substrate, and the first raw material is adsorbed on the substrate, and the second raw material is placed in the processing container. A predetermined film on the substrate by alternately repeating the step of forming the metal-containing layer by reacting the first raw material and the second raw material adsorbed on the substrate. There is provided a method for manufacturing a semiconductor device, comprising: a step of performing a process of forming a thick metal-containing film; and a step of carrying out a processed substrate from the processing container.

  Preferably, in the step of performing the process of forming the metal-containing film having the predetermined thickness, the bias voltage is applied between the spray nozzle and the substrate while supplying the first raw material containing the metal compound from the spray nozzle into the processing container. To spray the first raw material in a charged state and supply it to the substrate, and to adsorb the first raw material on the substrate, and to purge the inside of the processing container with an inert gas A step of forming a metal-containing layer by reacting the first raw material adsorbed on the substrate with the second raw material by supplying a second raw material into the processing container A process of purging the inside of the processing container with an inert gas is set as one cycle, and this cycle is repeated a plurality of times to form a metal-containing film having a predetermined thickness on the substrate.

  Preferably, the first raw material is an organometallic compound or a mixed solution of an organometallic compound and an organic compound having a boiling point lower than that at least.

  Preferably, the second raw material is an oxidizing agent, the metal-containing layer is a metal oxide layer, and the metal-containing film is a metal oxide film.

Preferably, the second raw material is water vapor (H ₂ O) or ozone (O ₃ ), the metal-containing layer is a metal oxide layer, and the metal-containing film is a metal oxide film.

  According to another aspect of the present invention, a processing container for accommodating a substrate, a first raw material supply system for supplying a first raw material containing a metal compound from a spray nozzle into the processing container, and a first container in the processing container. A second raw material supply system for supplying two raw materials, a bias voltage applying mechanism for applying a bias voltage between the spray nozzle and the substrate, and supplying the first raw material from the spray nozzle into the processing container. By applying a bias voltage between the spray nozzle and the substrate, the first raw material is sprayed in a charged state, supplied to the substrate, the first raw material is adsorbed on the substrate, and the processing is performed. By supplying the second raw material into the container, the first raw material adsorbed on the substrate reacts with the second raw material to form a metal-containing layer, and this is alternately repeated. On the substrate A substrate process comprising: a first raw material supply system, a second raw material supply system, and a control unit that controls the bias voltage application mechanism so as to form a metal-containing film having a predetermined thickness. An apparatus is provided.

DESCRIPTION OF SYMBOLS 12 Processing container 14 Wafer 16 Processing chamber 18 Support stand 20 Susceptor 22 Heater 24 Elevating mechanism 32 Wafer transfer port 34 Gate valve 36 Transfer chamber 40 Exhaust port 42 Exhaust pipe 44 Pressure regulator 48 Vacuum pump 70 Liquid raw material spray nozzle 72 Liquid oxidizing agent Spray nozzle 74 Gas oxidant inlet 76 Purge gas inlet 80, 82 Spray power supply 84 Support base power supply 100 Liquid raw material supply source 110 Liquid oxidant supply source 120 Gas oxidant supply source 140 Purge gas supply source 150 Controller

Claims (2)

A step of carrying the substrate into the processing container;
By applying a bias voltage between the spray nozzle and the substrate while supplying the first raw material containing the metal compound from the spray nozzle into the processing container, the first raw material is sprayed in a charged state. Supplying the substrate with the first raw material adsorbed on the substrate, and supplying the second raw material into the processing container, whereby the first raw material adsorbed on the substrate and the first raw material A step of forming a metal-containing layer on the substrate by alternately repeating the step of reacting the two raw materials to form a metal-containing layer, and
Unloading the processed substrate from within the processing container;
A method for manufacturing a semiconductor device, comprising: A processing container for containing a substrate;
A first raw material supply system for supplying a first raw material containing a metal compound from a spray nozzle into the processing container;
A second raw material supply system for supplying a second raw material into the processing container;
A bias voltage application mechanism for applying a bias voltage between the spray nozzle and the substrate;
By applying a bias voltage between the spray nozzle and the substrate while supplying the first raw material from the spray nozzle into the processing container, the first raw material is sprayed in a charged state on the substrate. The first raw material and the second raw material adsorbed on the substrate by supplying, adsorbing the first raw material on the substrate, and supplying the second raw material into the processing container. The first raw material supply system and the second raw material supply system are formed so as to form a metal-containing layer having a predetermined thickness on the substrate by alternately repeating this process. And a control unit for controlling the bias voltage application mechanism;
A substrate processing apparatus comprising:

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