JP5331224B2 - Substrate manufacturing method, semiconductor device manufacturing method, substrate processing method, cleaning method, and processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate manufacturing method, a semiconductor device manufacturing method, a substrate processing method, a cleaning method, and a processing device capable of improving operation rates. <P>SOLUTION: There is provided a substrate manufacturing method comprising the steps of: causing a gas introduction nozzle provided in a reaction tube to form an oxide film on a substrate supported by a supporter by introducing an oxidizable gas into the reaction tube; and cleaning the inside of the reaction tube by exporting the substrate on which the oxide film is formed from the reaction tube. The step of cleaning the inside of the reaction tube includes: a step of removing an oxide film formed on at least one of the reaction tube, the supporter, and the gas introduction nozzle by supplying the inside of the reaction tube with a hydrogen fluoride gas, a hydrogen fluoride gas and a hydrogen gas, or a gas containing at least a hydrogen fluoride gas and steam while the inside of the reaction tube is maintained at a predetermined temperature; and a step of supplying the inside of the reaction tube with an inactive gas while the predetermined temperature is maintained. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  The present invention relates to a substrate manufacturing method, a semiconductor device manufacturing method, a substrate processing method, a cleaning method, and a processing apparatus for processing a substrate such as a semiconductor wafer or a glass substrate.

  When a substrate is heat-treated using this type of heat treatment apparatus, a silicon oxide film is formed on each member such as a silicon carbide (SiC) or silicon (Si) reaction tube, a substrate support, and a gas introduction nozzle. In this case, when this silicon oxide film grows (accumulates) and becomes thicker, the silicon oxide film peels off due to the difference in thermal expansion between each member and the silicon oxide film, and particles are generated in the reaction furnace. There was a problem. Therefore, a cleaning process for removing the silicon oxide film from each member on which the silicon oxide film is formed is periodically performed.

  However, in this cleaning process, each member in the reaction furnace is removed, and the silicon oxide film is removed with an aqueous solution such as hydrogen fluoride (or a mixture of hydrogen fluoride and ammonium fluoride). Took a lot of time. Also, when attaching each member from which the cleaned silicon oxide film has been removed, particles, contaminants, etc. are mixed in the furnace. A process for removing these particles and contaminants by treatment is indispensable, which has been a factor in reducing the operating rate of the apparatus.

  An object of the present invention is to provide a substrate manufacturing method and a heat treatment apparatus that solve the above-mentioned conventional problems and improve the operating rate.

  The first feature of the present invention is that a gas introduction nozzle provided in a reaction tube introduces an oxidizing gas into the reaction tube and forms an oxide film on a substrate supported by a support; Unloading the substrate after film formation from the inside of the reaction tube and cleaning the inside of the reaction tube, and the step of cleaning the inside of the reaction tube maintains the inside of the reaction tube at a predetermined temperature. By supplying a gas containing at least hydrogen fluoride gas, hydrogen fluoride gas and hydrogen gas, or hydrogen fluoride gas and water vapor into the tube, at least one of the reaction tube, the support, and the gas introduction nozzle And a step of removing the oxide film formed on the member and a step of supplying an inert gas into the reaction tube while maintaining the predetermined temperature. It lies in the way.

  The second feature of the present invention is that a gas introduction nozzle provided in a reaction tube introduces an oxidizing gas into the reaction tube and forms an oxide film on a substrate supported by a support; Unloading the substrate after film formation from the inside of the reaction tube and cleaning the inside of the reaction tube, and the step of cleaning the inside of the reaction tube maintains the inside of the reaction tube at a predetermined temperature. By supplying a gas containing at least hydrogen fluoride gas, hydrogen fluoride gas and hydrogen gas, or hydrogen fluoride gas and water vapor into the tube, at least one of the reaction tube, the support, and the gas introduction nozzle A step of removing an oxide film formed on the member, and a step of supplying an inert gas into the reaction tube while maintaining the predetermined temperature. It lies in the way of production.

  A third feature of the present invention is that a gas introduction nozzle provided in a reaction tube introduces an oxidizing gas into the reaction tube and forms an oxide film on a substrate supported by a support; Unloading the substrate after film formation from the inside of the reaction tube and cleaning the inside of the reaction tube, and the step of cleaning the inside of the reaction tube maintains the inside of the reaction tube at a predetermined temperature. By supplying a gas containing at least hydrogen fluoride gas, hydrogen fluoride gas and hydrogen gas, or hydrogen fluoride gas and water vapor into the tube, at least one of the reaction tube, the support, and the gas introduction nozzle A substrate process comprising: removing an oxide film formed on the member; and supplying an inert gas into the reaction tube while maintaining the predetermined temperature. There is the law.

  The fourth feature of the present invention is that a gas introduction nozzle provided in the reaction tube is used to introduce an oxidizing gas into the reaction tube and form an oxide film on the substrate supported by the support. A method of cleaning the inside of the reaction tube later, wherein the step of cleaning the inside of the reaction tube is performed with hydrogen fluoride gas, hydrogen fluoride gas and hydrogen in the reaction tube while maintaining the inside of the reaction tube at a predetermined temperature. A step of removing an oxide film formed on at least one of the reaction tube, the support, and the gas introduction nozzle by supplying a gas or a gas containing at least hydrogen fluoride gas and water vapor And a step of supplying an inert gas into the reaction tube while maintaining the predetermined temperature.

  A fifth feature of the present invention is that a reaction vessel for processing a substrate, a support for supporting the substrate in the reaction tube, and a reaction tube are provided, and an oxide film is formed on the substrate in the reaction tube. A gas introduction nozzle for introducing an oxidizing gas for forming the reaction tube, and is formed on at least one of the reaction tube, the support, and the gas introduction nozzle in a state in which the inside of the reaction tube is maintained at a predetermined temperature. A cleaning gas supply line for supplying hydrogen fluoride gas, hydrogen fluoride gas and hydrogen gas, or a gas containing at least hydrogen fluoride gas and water vapor to remove the oxidized film, and maintaining the predetermined temperature In the processing apparatus, a purge gas supply line for supplying an inert gas is provided in the reaction tube.

  According to the present invention, the gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas is supplied into the reaction tube to remove the oxide film formed on each member, thereby removing and attaching each member. Work can be omitted, and the operating rate of the apparatus can be improved.

It is a perspective view which shows the whole heat processing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the reaction furnace used for the heat processing apparatus which concerns on embodiment of this invention.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an example of a heat treatment apparatus 10 according to an embodiment of the present invention. This heat treatment apparatus 10 is a batch type vertical heat treatment apparatus and has a casing 12 in which a main part is arranged. A pod stage 14 is connected to the front side of the housing 12, and the pod 16 is conveyed to the pod stage 14. For example, 25 wafers as substrates to be processed are stored in the pod 16 and set on the pod stage 14 with a lid (not shown) closed.

  A pod transfer device 18 is disposed on the front side in the housing 12 and at a position facing the pod stage 14. Further, a pod shelf 20, a pod opener 22, and a substrate number detector 24 are arranged in the vicinity of the pod transfer device 18. The pod shelf 20 is disposed above the pod opener 22, and the substrate number detector 24 is disposed adjacent to the pod opener 22. The pod carrying device 18 carries the pod 16 among the pod stage 14, the pod shelf 20, and the pod opener 22. The pod opener 22 opens the lid of the pod 16, and the number of substrates in the pod 16 with the lid opened is detected by the substrate number detector 24.

  Further, a substrate transfer machine 26, a notch aligner 28, and a substrate support (boat) 30 made of silicon carbide (SiC) as a support are arranged in the housing 12. The substrate transfer machine 26 has, for example, an arm (tweezer) 32 that can take out five substrates. By moving this arm 32, the pod placed at the position of the pod opener 22, the notch aligner 28, and the substrate. The substrate is transferred between the support tools 30. The notch aligner 28 detects notches or orientation flats formed on the substrate and aligns the notches or orientation flats of the substrate at a certain position.

  Further, a reaction furnace 40 is disposed at the upper part on the back side in the housing 12. The substrate support 30 loaded with a plurality of substrates is carried into the reaction furnace 40 and subjected to heat treatment.

  An example of the reaction furnace 40 is shown in FIG. The reaction furnace 40 has a reaction tube 42 made of silicon carbide (SiC). The reaction tube 42 has a cylindrical shape in which the upper end is closed and the lower end is opened, and the opened lower end is formed in a flange shape. A heater 46 is disposed around the reaction tube 42.

  The lower part of the reaction tube 42 is opened to insert the substrate support 30, and this open part (furnace port part) is sealed by the furnace port seal cap 48 contacting the O-ring 49. is there. The furnace port seal cap 48 supports the substrate support 30 made of silicon carbide (SiC) and is provided so as to be movable up and down together with the substrate support 30. Between the furnace port seal cap 48 and the substrate support 30, there is a first heat insulating member 52 made of quartz, and a second made of silicon carbide (SiC) disposed above the first heat insulating member 52. A heat insulating member 50 is provided. The substrate support 30 is used as a support for supporting the substrate. The substrate support 30 supports a large number of, for example, 25 to 100 substrates 54 in multiple stages with a gap in a substantially horizontal state, and is loaded into the reaction tube 42.

  The reaction tube 42 is provided with a gas supply line 60 and a gas exhaust line 62. The gas introduction nozzle 66 is provided in the reaction tube 42 and is connected to the downstream end of the gas supply line 60. The processing gas introduced into the gas supply line 60 is supplied into the reaction tube 42 via the gas introduction nozzle 66. The gas introduction nozzle 66 is configured to extend above the upper end of the substrate arrangement region along the inner wall of the reaction tube 42, that is, above the upper end of the substrate support 30.

  The gas supply line 60 includes nitrogen (N2) gas, argon (Ar) gas, hydrogen (H2) gas, oxygen (O2) gas, hydrogen fluoride (HF) gas, chlorine fluoride (ClF3) gas, and water vapor (H2O). These gases (or at least two kinds of mixed gases) are supplied into the reaction tube 40 via the gas supply line 60 and the gas introduction nozzle 66. It has become. The flow rate of the gas supplied into the reaction tube 42 is controlled by the controller 70.

Next, the operation of the heat treatment apparatus 10 will be described.
In the following description, the operation of each part constituting the heat treatment apparatus 10 is controlled by the controller 70.

  First, when the pod 16 containing a plurality of substrates 54 is set on the pod stage 14, the pod 16 is transferred from the pod stage 14 to the pod shelf 20 by the pod transfer device 18 and stocked on the pod shelf 20. Next, the pod 16 stocked on the pod shelf 20 is transported and set to the pod opener 22 by the pod transport device 18, the lid of the pod 16 is opened by the pod opener 22, and the pod 16 is detected by the substrate number detector 24. The number of substrates 54 accommodated in is detected.

  Next, the substrate transfer machine 26 takes out the substrate 54 from the pod 16 at the position of the pod opener 22 and transfers it to the notch aligner 28. In the notch aligner 28, the notch is detected while rotating the substrate 54, and the notches of the plurality of substrates 54 are aligned at the same position based on the detected information. Next, the substrate transfer device 26 takes out the substrate 54 from the notch aligner 28 and transfers it to the substrate support 30 (substrate support step).

  In this way, when one batch of the substrates 54 is transferred to the substrate support 30, for example, a substrate in which a plurality of substrates 54 are loaded in the reaction furnace 40 (reaction vessel 43) set to a temperature of about 600 ° C. The support 30 is loaded (carrying in), and the inside of the reaction furnace 40 is sealed with the furnace port seal cap 48 (substrate carrying-in process). Next, the furnace temperature is raised to the heat treatment temperature to oxidize the substrate 54 such as oxygen (O 2) gas or water vapor (H 2 O) in the reaction tube 42 via the gas supply line 60 and the gas introduction nozzle 66. Introducing the oxidizing gas. When the substrate 54 is heat-treated, the substrate 54 is heated to a temperature of about 1350 ° C. or more, for example, and the surface of the substrate 54 is oxidized (oxidation process).

  When the heat treatment of the substrate 54 is completed, for example, the temperature in the furnace is lowered to a temperature of about 600 ° C., and then the substrate support 30 supporting the substrate 54 after the heat treatment (after oxidation) is unloaded from the reaction tube 42 (unloading step). ) The substrate support 30 is made to wait at a predetermined position until all the substrates 54 supported by the substrate support 30 are cooled. Next, when the substrate 54 of the substrate support 30 that has been put on standby is cooled to a predetermined temperature, the substrate transfer device 26 takes out the substrate 54 from the substrate support 30, and the empty pod set in the pod opener 22. It is conveyed to 16 and accommodated. Next, the pod transport device 18 transports the pod 16 containing the substrate 54 to the pod shelf 20 or the pod stage 14 to complete a series of processes. The reaction tube 42 is cleaned after the above-described series of processing is performed a predetermined number of times (predetermined time) or at a desired timing (cleaning step).

Next, an example of the above-described cleaning process will be described.
In the cleaning step, a silicon oxide film having a predetermined thickness is formed on the inner wall of the reaction tube 42, the substrate support 30, the first heat insulating member 52, the second heat insulating member 54, the gas introduction nozzle 66, and the like by the above-described oxidation step. To be implemented.

  First, the controller 70 supplies a cleaning gas containing at least one of hydrogen fluoride (HF) gas and chlorine fluoride (ClF 3) gas into the reaction tube 42 from a gas supply source (not shown). More specifically, the controller 70 includes a mixed gas (HF + N2) of hydrogen fluoride (HF) gas and nitrogen (N2) gas, and a mixed gas (HF + Ar) of hydrogen fluoride (HF) gas and argon (Ar) gas. ), A gas selected from a mixed gas (HF + H2) of hydrogen fluoride (HF) gas and hydrogen (H2) gas and a mixed gas (HF + H2O) of hydrogen fluoride (HF) gas and water vapor (H2O) The reaction tube 40 is supplied for a predetermined time through the line 60 and the gas introduction nozzle 66. The cleaning reaction is accelerated by supplying a small amount of water vapor (H 2 O) or hydrogen (H 2) into the reaction tube 42.

  Thereby, the silicon oxide films formed on the inner wall of the reaction tube 42, the substrate support 30, the first heat insulating member 52, the second heat insulating member 54, the gas introduction nozzle 66, and the like are removed by the reaction with the cleaning gas. The The cleaning gas species is not limited to those containing hydrogen fluoride (HF) gas and chlorine fluoride (ClF 3) described above, but reacts with the silicon oxide film and is a member of silicon carbide (SiC) or silicon (Si). Any gas that does not react with or has low reactivity may be used.

  Subsequently, the controller 70 supplies an inert gas into the reaction tube 42 from a gas supply source (not shown). More specifically, the controller 70 supplies (purges), for example, argon (Ar) gas, nitrogen (N 2) gas or the like into the reaction tube 42 through the gas supply line 60 and the gas introduction nozzle 66 for a predetermined time. Thereby, the cleaning gas in the reaction tube 42 is replaced with the inert gas.

  This cleaning process is automatically performed under the control of the controller 70. The cleaning gas may be supplied into the reaction tube 40 through a different path from the gas supply line 60 to which the processing gas is supplied and the gas introduction nozzle.

  Next, examples and comparative examples will be described.

[Example]
First, an oxidation process (including an annealing process) was performed in the heat treatment apparatus 10. The oxidation (or annealing) temperature in this oxidation step was 1350 ° C., and the oxidation time was 750 hours (continuous use time). Subsequently, a cleaning process was performed in the heat treatment apparatus 10. That is, the cleaning gas was supplied into the reaction tube 40 through the gas supply line 60 and the gas introduction nozzle 66 under the control of the controller 70 for a predetermined time. Subsequently, under the control of the controller 70, an inert gas was supplied (purged) into the reaction tube 40 through the gas supply line 60 and the gas introduction nozzle 66 for a predetermined time. The cleaning gas species in this example was a mixed gas (HF + Ar) of hydrogen fluoride (HF) gas and argon (Ar) gas.

  It took 60 minutes to remove the silicon oxide film formed on each member such as the inner wall of the reaction tube 42, the substrate support 30, the gas introduction nozzle 66, and the first heat insulating member 52, and 20 minutes to purge time. The cleaning temperature was 80 ° C. That is, the time required for the cleaning process in this example was 80 minutes.

[Comparative example]
First, an oxidation step (including an annealing step) similar to that in the above example was performed in the heat treatment apparatus 10. Subsequently, a cleaning process was performed. In the cleaning process in this comparative example, each member such as the reaction tube 42, the substrate support 30, the gas introduction nozzle 66, the first heat insulating member 52, and the like was removed by two workers, and each member was formed with a cleaning liquid. After removing the silicon oxide film and washing and drying each member, the two members attach and adjust each member in the reaction furnace 40 to heat (bake) the reaction furnace 40. The cleaning liquid type in this comparative example was a mixed liquid (HF + NH4F) of hydrogen fluoride (HF) and an aqueous ammonium fluoride solution (NH4F). In addition, water (H 2 O) was used for washing after cleaning.

  120 minutes for removing each member such as the reaction tube 42, the substrate support 30, the gas introduction nozzle 66, the first heat insulating member 52, and 1440 minutes for removing the silicon oxide film formed on each member and washing with water, It took 240 minutes to dry the members, 240 minutes to attach and adjust each member, and 1440 minutes to heat (blank) the reactor 40. Therefore, the time required for the cleaning process in this comparative example was 3480 minutes.

  As described above, the cleaning process in the heat treatment apparatus 10 of the present invention can significantly reduce the time required for the cleaning process as compared with the cleaning process in the comparative example, thereby improving the operating rate of the apparatus. it can. In addition, since the cleaning process in the heat treatment apparatus 10 of the present invention is automatically performed by the controller 70, the burden on the operator is reduced as compared with the cleaning process in the comparative example.

  Each member such as the reaction tube 42, the substrate support 30, the gas introduction nozzle 66, and the first heat insulating member 52 may be made of silicon (Si) instead of silicon carbide (SiC). In this case, the silicon oxide film formed on each member made of silicon (Si) is preferably removed with a cleaning gas containing hydrogen fluoride (HF) gas.

The heat treatment apparatus of the present invention can be applied to a substrate manufacturing process.
An example in which the heat treatment apparatus of the present invention is applied to one process of manufacturing a SIMOX (Separation by Implanted Oxygen) wafer, which is a kind of SOI (Silicon On Insulator) wafer, will be described.

  First, oxygen ions are implanted into the single crystal silicon wafer by an ion implantation apparatus or the like. Thereafter, the wafer into which oxygen ions are implanted is annealed at a high temperature of 1300 ° C. to 1400 ° C., for example, 1350 ° C. or higher, for example, in an Ar, O 2 atmosphere using the heat treatment apparatus of the above embodiment. By these processes, a SIMOX wafer in which a SiO 2 layer is formed inside the wafer (an SiO 2 layer is embedded) is produced.

  The heat treatment apparatus of the present invention can be applied even when performing a high-temperature annealing treatment performed as one step of such a substrate manufacturing process.

  The heat treatment apparatus of the present invention can also be applied to a semiconductor device (device) manufacturing process. In particular, it is preferably applied to a heat treatment step performed at a relatively high temperature, for example, a thermal oxidation step such as wet oxidation, dry oxidation, hydrogen combustion oxidation (pyrogenic oxidation), HCl oxidation, or the like.

  The heat treatment apparatus of the present invention can also be applied when performing a heat treatment step as one step of the semiconductor device manufacturing step.

  INDUSTRIAL APPLICABILITY The present invention can be used in a method for manufacturing a substrate such as a semiconductor wafer or a glass substrate and a heat treatment apparatus that require cleaning of the reaction tube and each member in the reaction tube.

DESCRIPTION OF SYMBOLS 10 Heat processing apparatus 30 Substrate support 42 Reaction tube 54 Substrate 60 Gas supply line 66 Gas introduction nozzle

Claims (5)

A step of introducing an oxidizing gas into the reaction tube by a gas introduction nozzle provided in the reaction tube to form an oxide film on a substrate supported by a support;
Removing the substrate after forming the oxide film from the inside of the reaction tube, and cleaning the inside of the reaction tube,
The step of cleaning the inside of the reaction tube includes:
By supplying a gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas into the reaction tube while maintaining the inside of the reaction tube at a predetermined temperature, the reaction tube, the support, and the gas introduction nozzle Each member is made of silicon carbide, and removing the oxide film formed on the member made of silicon carbide ;
And a step of supplying an inert gas into the reaction tube. A step of introducing an oxidizing gas into the reaction tube by a gas introduction nozzle provided in the reaction tube to form an oxide film on a substrate supported by a support;
Removing the substrate after forming the oxide film from the inside of the reaction tube, and cleaning the inside of the reaction tube,
The step of cleaning the inside of the reaction tube includes:
By supplying a gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas into the reaction tube while maintaining the inside of the reaction tube at a predetermined temperature, the reaction tube, the support, and the gas introduction nozzle Each of the members is made of silicon carbide, and the step of removing the oxide film formed on the member made of silicon carbide ;
The method of manufacturing a semiconductor device which comprises a step of supplying an inert gas into the reaction tube. A step of introducing an oxidizing gas into the reaction tube by a gas introduction nozzle provided in the reaction tube to form an oxide film on a substrate supported by a support;
Removing the substrate after forming the oxide film from the inside of the reaction tube, and cleaning the inside of the reaction tube,
The step of cleaning the inside of the reaction tube includes:
By supplying a gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas into the reaction tube while maintaining the inside of the reaction tube at a predetermined temperature, the reaction tube, the support, and the gas introduction nozzle Each of the members is made of silicon carbide, and the step of removing the oxide film formed on the member made of silicon carbide ;
And a step of supplying an inert gas into the reaction tube. A method of cleaning the inside of the reaction tube after performing a process of introducing an oxidizing gas into the reaction tube and forming an oxide film on a substrate supported by a support by a gas introduction nozzle provided in the reaction tube. ,
The step of cleaning the inside of the reaction tube includes:
By supplying a gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas into the reaction tube while maintaining the inside of the reaction tube at a predetermined temperature, the reaction tube, the support, and the gas introduction nozzle Each of the members is made of silicon carbide, and the step of removing the oxide film formed on the member made of silicon carbide ;
Cleaning method which comprises a step of supplying an inert gas into the reaction tube. A reaction vessel for processing the substrate;
A support for supporting the substrate in the reaction tube;
A gas introduction nozzle that is provided in the reaction tube and introduces an oxidizing gas for forming an oxide film on the substrate in the reaction tube;
In a state where the inside of the reaction tube is maintained at a predetermined temperature, each member of the reaction tube, the support, and the gas introduction nozzle is made of silicon carbide, and an oxide film formed on the member made of silicon carbide is formed. A cleaning gas supply line for supplying a gas containing at least one of hydrogen fluoride gas and chlorine fluoride gas for removal;
And a purge gas supply line for supplying an inert gas into the reaction tube.

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