JP4723037B2 - Semiconductor device manufacturing method, cleaning method, and substrate processing apparatus - Google Patents

Description

  The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus, and more particularly to a cleaning technique in a reaction furnace.

2. Description of the Related Art A vertical CVD apparatus that collectively processes a plurality of substrates is known as a semiconductor manufacturing apparatus that performs a semiconductor device manufacturing method. Using a reaction furnace of this vertical CVD apparatus, a polysilicon film called a flat polysilicon film is formed on a plurality of substrates. Here, “flat” means to make the temperature gradient in the furnace flat (zero). Therefore, the flat polysilicon film refers to a polysilicon film formed on a plurality of substrates arranged in a furnace having a flat temperature gradient. Here, a region in the furnace where a plurality of substrates are arranged is referred to as a substrate arrangement region.
In forming the flat polysilicon film, a film forming gas nozzle called a long nozzle is used in order to uniformly supply a film forming gas to the entire substrate arrangement region. Here, the long nozzle refers to a film forming gas nozzle capable of supplying a film forming gas not from outside the substrate arrangement region in the furnace but from inside the substrate arrangement region in the furnace. In a reaction furnace of a vertical CVD apparatus, this long nozzle is usually inserted from the lower part of the furnace and extends toward the upper part of the furnace, so that it is inserted from the lower part in the furnace and stops there. The length is longer than the normal nozzle. For the formation of the flat polysilicon film described above, a plurality of, for example, four quartz long nozzles (hereinafter referred to as quartz long nozzles) having different lengths along the substrate arrangement region are used.
By the way, when the film formation is repeated in the reaction furnace, a product film as a by-product is deposited in the reaction furnace. When the deposited film thickness is 10 μm or more, it becomes a factor for generation of particles, and thus it is necessary to remove the deposited film once. Etching with a cleaning gas is employed to remove the film in the reactor. For example, when a polysilicon film is formed by supplying SiH ₄ into the reaction furnace, etching with ClF ₃ gas is effective. Here, the polysilicon film is naturally formed not only on the inner wall of the reaction furnace but also on the inner wall of the quartz long nozzle used for forming the flat polysilicon film. Therefore, it is necessary to etch the deposited films on both the inner wall of the reactor and the inner wall of the quartz long nozzle. In this case, the deposited film thickness in the deposition gas nozzle is generally 4 times or more thicker than the deposited film thickness in the reaction furnace. For this reason, it is necessary to clean the inside of the film forming gas nozzle separately from the cleaning inside the reaction furnace.
Therefore, conventionally, cleaning gas is introduced into the reaction furnace from the cleaning gas nozzle to clean the inside of the reaction furnace, and cleaning gas is also introduced into the film forming gas nozzle to clean the inside of the film forming gas nozzle. Yes. In this case, in addition to the method of simultaneously performing the cleaning process of the inner wall of the film forming gas nozzle and the cleaning process of the inner wall of the reaction tube, a method of performing these cleaning processes separately has also been proposed ( For example, see Patent Document 1).
JP 2000-68214 A (paragraph number 0091, etc.)

However, when the cleaning process for the inner wall of the film forming gas nozzle and the cleaning process for the inner wall of the reaction tube are performed simultaneously as in the method of Patent Document 1, it is necessary to match the cleaning time with the cleaning time required for the inner wall of the reaction tube. This is not preferable because devitrification occurs in the film forming gas nozzle.
Also, in the other method of Patent Document 1 in which the cleaning process for the inner wall of the film forming gas nozzle and the cleaning process for the inner wall of the reaction tube are performed separately, the inner wall of the film forming gas nozzle is also cleaned. Since the cleaning is performed under the same conditions (same gas flow rate, etc.), the film forming gas nozzle is greatly damaged and may not be reused. In particular, in the case of a long nozzle, the damage is great due to its shape, and it cannot be reused. Therefore, instead of cleaning the film forming gas nozzle for each maintenance, the film forming gas nozzle is replaced with a new one and cleaning is performed only in the reaction furnace.
That is, if the cleaning conditions for the inner wall of the film forming gas nozzle and the inner wall of the reaction tube are the same, the cleaning of the inner wall of the reaction tube is insufficient when the cleaning gas flow rate is low, and the cleaning gas flow rate is too high. There was a problem that the inner wall of the film forming gas nozzle was excessively cleaned.
An object of the present invention is to solve the above-mentioned problems of the prior art, reduce the damage of the film forming gas nozzle during cleaning, and reduce the cost and downtime of the apparatus during maintenance. And a substrate processing apparatus.

  The first invention includes a step of carrying a substrate into the reaction furnace, a step of supplying a film forming gas into the reaction furnace from at least one film forming gas nozzle to form a thin film on the substrate, A step of unloading the substrate from the reaction furnace, a first cleaning step of supplying a cleaning gas set to a first condition from the film formation gas nozzle into the reaction furnace, and a supply of a cleaning gas different from the film formation gas nozzle into the reaction furnace And a second cleaning step for supplying a cleaning gas set to a second condition from the mouth.

  When the step of loading the substrate into the reaction furnace, the step of forming the film on the substrate, and the step of unloading the substrate from the reaction furnace are repeated, the film generated during the film formation step is deposited in the film forming gas nozzle and in the reaction furnace. I will do it. This deposited film is removed by two cleaning steps.

  In the first cleaning step, the cleaning gas set to the first condition is supplied into the reaction furnace from the film forming gas nozzle. At this time, the formed film deposited in the film forming gas nozzle can be removed according to the first condition. It is preferable that the first condition is a condition in which the generated film deposited in the film forming gas nozzle can be preferentially etched.

  In the second cleaning step, the cleaning gas set to the second condition is supplied into the reaction furnace from the cleaning gas supply port. At this time, the formed film deposited in the reaction furnace can be removed according to the second condition. In addition, since a cleaning gas supply port different from the film forming gas nozzle is used as a supply port for supplying the cleaning gas, it is possible to supply an inert gas from the film forming gas nozzle, whereby in the second cleaning step, Intrusion of the cleaning gas into the film forming gas nozzle can be prevented. The second condition is preferably a condition that allows the preferential etching of the generated film deposited in the reaction furnace.

  Thus, since the first condition is set in the first cleaning step and the second condition is set in the second cleaning step, damage to the film forming gas nozzle can be reduced in the first cleaning step. . Therefore, it is possible to extend the time for replacing the film forming gas nozzle, which has been conventionally performed every time the inside of the reactor is cleaned. As a result, the manufacturing cost of the semiconductor manufacturing apparatus can be reduced. In addition, the time required for replacing the film forming gas nozzle can be reduced, and the downtime of the reactor can be shortened.

The first cleaning step and the second cleaning step can be performed simultaneously. It is also possible to execute either the first cleaning step or the second cleaning step first. When either one is performed first, it is preferable to perform the cleaning of the film forming gas nozzle first. After cleaning the deposition gas nozzle,
This is because there is a concern about the generation of particles.

  The first invention includes a step of carrying a substrate into the reaction furnace, a step of supplying a film forming gas into the reaction furnace from at least one film forming gas nozzle to form a thin film on the substrate, and a film forming process. A step of unloading the subsequent substrate from the reaction furnace, a first cleaning step of supplying a cleaning gas from the film forming gas nozzle into the reaction furnace maintained under the first condition, and a second condition different from the first condition And a second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle while supplying an inert gas from the film forming gas nozzle into the reaction furnace held by the semiconductor. It is good also as a manufacturing method of an apparatus.

  Examples of the first and second conditions include a cleaning gas flow rate and a cleaning gas concentration. An example of the substrate is a silicon wafer. Examples of the reaction furnace include a batch type vertical CVD apparatus and a single wafer type CVD apparatus. In the case of a vertical CVD apparatus, the transport means for executing the step of carrying the substrate in and out of the reaction furnace includes an elevating means for raising and lowering a substrate holder such as a boat. In the case of a single wafer type CVD apparatus, a substrate transfer means can be mentioned.

The at least one film forming gas nozzle may be a single system nozzle in which one film forming gas nozzle is provided for each film forming gas type, or a multi-system in which a plurality of film forming gas nozzles are provided for each film forming gas type. A nozzle may be used. In multi-system nozzles, that is, a plurality of film forming gas nozzles, the lengths of the respective film forming gas nozzles can be the same. It is preferable that the gas can be uniformly supplied to each substrate from each nozzle having a different position with respect to each substrate arranged in the substrate arrangement region so as to be different from the arrangement region.
The cleaning gas supply port does not need to be a nozzle unlike the film formation gas nozzle, and only one supply port is provided separately from the film formation gas nozzle. Examples of the step of forming a thin film on the substrate include a step of forming a polysilicon film. Examples of the cleaning gas include ClF ₃ , NF ₃ , F ₂ , and HF. Inert gas for diluting the cleaning gas N ₂ is preferable.

A second invention is a method of manufacturing a semiconductor device according to the first invention, wherein in the first cleaning step, an inert gas is supplied from a cleaning gas supply port.
When an inert gas is supplied from the cleaning gas supply port in the first cleaning step, the concentration of the cleaning gas supplied from the film forming gas nozzle into the reaction furnace can be adjusted. Further, the cleaning gas from the film forming gas nozzle can enter the cleaning gas supply port or the cleaning gas nozzle, and the inside of the cleaning gas supply port can be prevented from receiving unnecessary damage.

In a third invention, in the first invention, the first condition is a condition capable of preferentially etching the formed film deposited in the film forming gas nozzle, and the second condition is in the reactor. The method for manufacturing a semiconductor device is characterized in that the pre-etched product film is preferentially etched.
In the first cleaning step, if the product film deposited in the deposition gas nozzle is etched under the same condition as the second condition in which the product film deposited in the reactor can be preferentially etched, In one cleaning step, the film forming gas nozzle is damaged. In this respect, the first condition is set such that the generated film deposited in the deposition gas nozzle can be preferentially etched, and the generated film deposited in the reactor is preferentially etched. Therefore, the damage to the film forming gas nozzle can be reduced in the first cleaning step. In the second cleaning step, the conditions are set such that the product film deposited in the reaction furnace can be preferentially etched, so that the product film deposited in the reaction furnace can be effectively removed.

  The first condition that allows the preferential etching of the formed film deposited in the film forming gas nozzle is to lower the cleaning gas concentration or reduce the cleaning gas flow rate than the second condition. Can be mentioned. The second condition that allows the preferential etching of the product film deposited in the reaction furnace is to increase the concentration of the cleaning gas or increase the cleaning gas flow rate than the first condition. To do.

A fourth invention is a method of manufacturing a semiconductor device according to the first invention, characterized in that the cleaning gas flow rate is smaller in the first cleaning step than in the second cleaning step.
By making the cleaning gas flow rate smaller in the first cleaning step than in the second cleaning step, the film forming gas nozzle is not damaged in the first cleaning step without damaging the film forming gas nozzle. The deposited product film can be effectively removed. Further, in the second cleaning step, the formed film deposited in the reaction furnace can be effectively removed.

A fifth invention is a method for manufacturing a semiconductor device according to the first invention, wherein, in the film forming step, a silicon film is formed using SiH ₄ .
When a silicon film is formed using SiH ₄ in the film forming step, the silicon film generated in accordance with the film forming step is deposited in the film forming gas nozzle and the reaction furnace.
Thus, even when the step of forming a silicon film using SiH ₄ is included, the first condition for cleaning the inside of the film forming gas nozzle is different from the second condition for cleaning the inside of the reaction furnace. Therefore, in the first cleaning step, the silicon film deposited in the film forming gas nozzle can be removed without damaging the film forming gas nozzle. Further, in the second cleaning step, the formed film deposited in the reaction furnace can be effectively removed. Examples of the silicon film include a polysilicon film and an amorphous silicon film.

A sixth invention is a method for manufacturing a semiconductor device according to the first invention, wherein, in the film forming step, a film forming gas is supplied into the reaction furnace from a plurality of film forming gas nozzles having different lengths.
Even in the case where a film forming gas is supplied from a plurality of film forming gas nozzles having different lengths into the reaction furnace to form a thin film on the substrate, the first film forming gas nozzle is cleaned. Since the conditions and the second condition for cleaning the inside of the reaction furnace are different, in the first cleaning step, the formed films deposited in the plurality of film forming gas nozzles having different lengths are converted into the plurality of film forming gas nozzles. Can be removed without causing damage. In this case, it is preferable to change the supply time of the cleaning gas from the film forming gas nozzle into the reaction furnace in accordance with the length of the plurality of film forming gas nozzles. Further, in the second cleaning step, the formed film deposited in the reaction furnace can be effectively removed.
The plurality of film forming gas nozzles having different lengths described above are disposed at different positions in the substrate arrangement region in the reaction furnace in which the plurality of substrates are arranged, particularly in a vertical CVD apparatus that collectively processes a plurality of substrates. And is provided in order to uniformly supply a film forming gas to a plurality of substrates.

In a seventh aspect of the present invention, in the first aspect, in the film formation step, the temperature gradient in the reaction furnace is flattened, and the film formation gas is supplied into the reaction furnace from a plurality of film formation gas nozzles having different lengths. A feature of the present invention is a method for manufacturing a semiconductor device.
Even when the film forming step includes a step in which the temperature gradient in the reaction furnace is flattened and the film forming gas is supplied into the reaction furnace from a plurality of film forming gas nozzles having different lengths. Since the first condition for cleaning the inside of the film gas nozzle is different from the second condition for cleaning the inside of the reaction furnace, the first gas is deposited in the plurality of film forming gas nozzles having different lengths in the first cleaning step. The generated film can be effectively removed without damaging the plurality of film forming gas nozzles. Further, in the second cleaning step, the formed film deposited in the reaction furnace can be effectively removed.
As described above, the reason why the temperature gradient in the reaction furnace is made flat is that, in particular, in a vertical CVD apparatus that collectively processes a plurality of substrates, the film formation temperature is made the same among the plurality of substrates. In addition, the plurality of film forming gas nozzles having different lengths are disposed at different positions in the substrate arrangement region in the reaction furnace in which the plurality of substrates are arranged, particularly in a vertical CVD apparatus that collectively processes a plurality of substrates. The film forming gas is uniformly supplied to a plurality of substrates.

An eighth invention is the method of manufacturing a semiconductor device according to the first invention, wherein the cleaning gas is ClF ₃ gas.
The first condition for cleaning the inside of the plurality of film forming gas nozzles is different from the second condition for cleaning the inside of the reaction furnace, and ClF ₃ gas is supplied as the cleaning gas in the first and second cleaning steps. Therefore, the generated film deposited in the film forming gas nozzle can be effectively removed without damaging the film forming gas nozzle. In addition, the formed film deposited in the reaction furnace can be effectively removed.

  According to a ninth aspect of the present invention, there is provided a reaction furnace that accommodates a substrate, a transport means that transports the substrate to the reaction furnace, at least one film forming gas nozzle that supplies gas into the reaction furnace, and the reaction furnace. A cleaning gas nozzle that is different from a film forming gas nozzle that supplies a gas; a transport unit; and a control unit that controls the gas supplied into the reactor from the film forming gas nozzle and the cleaning gas nozzle, respectively. In the transfer step, the substrate is carried into the reaction furnace, and the substrate after film formation is unloaded from the reaction furnace. In the film formation step, a film formation gas is supplied into the reaction furnace from at least one film formation gas nozzle, and a thin film is formed on the substrate. In the first cleaning step, the cleaning gas is supplied from the film forming gas nozzle into the reactor maintained at the first condition, and the second cleaning step. In this case, the inert gas is supplied from the film forming gas nozzle into the reaction furnace maintained at the second condition different from the first condition, and the cleaning gas is supplied from the cleaning gas nozzle different from the film forming gas nozzle. There is provided a semiconductor manufacturing apparatus.

  According to this, in the first cleaning step, the cleaning gas is supplied from the film forming gas nozzle into the reaction furnace maintained at the first condition, and in the second cleaning step, the reaction is performed in the reaction furnace maintained at the second condition. Since the control means for controlling the supply of the cleaning gas from the cleaning gas nozzle while supplying the inert gas from the film gas nozzle is provided, the semiconductor device manufacturing method of the first invention can be easily implemented.

  According to the present invention, damage to the film forming gas nozzle at the time of cleaning can be reduced, and the cost at the time of maintenance and the downtime of the apparatus can be reduced.

It is a schematic sectional drawing of the vertical type CVD apparatus by embodiment. It is explanatory drawing of the furnace 2 step | paragraph cleaning sequence by embodiment.

Embodiments of the present invention will be described below.
FIG. 1 is a schematic cross-sectional view of a vertical CVD apparatus showing a semiconductor manufacturing apparatus according to an embodiment. The vertical CVD apparatus includes a reaction furnace having a reaction space for mainly processing a substrate, and a transport means for transporting the substrate held by the substrate holding member to the reaction furnace, and the substrate holding member is accommodated in the reaction furnace. And configured to process the substrate.

The reaction furnace 31 includes a reaction tube 37 and a heating device (hereinafter referred to as a heater 39). The reaction tube 37 includes an outer tube (hereinafter referred to as an outer tube 115) and an inner tube (hereinafter referred to as an inner tube 116). The outer tube 115 is made of a heat-resistant material such as quartz (SiO ₂ ), and has a cylindrical shape with the upper end closed and the lower end opened. The inner tube 116 has a cylindrical shape having openings at both ends of the upper end and the lower end, and is disposed coaxially in the outer tube 115. A space between the outer tube 115 and the inner tube 116 forms a cylindrical space 114. The gas rising from the upper opening of the inner tube 116 passes through the cylindrical space 114 and is exhausted from the exhaust system (hereinafter referred to as the exhaust pipe 111). The control system of the reaction furnace 31 is controlled by the control means 103.

  A manifold 117 made of, for example, stainless steel is engaged with lower ends of the outer tube 115 and the inner tube 116, and the outer tube 115 and the inner tube 116 are held by the manifold 117. An annular flange is provided at each of the lower end portion of the outer tube 115 and the upper opening end portion of the manifold 117, and the space between these flanges is hermetically sealed.

  A disc-shaped lid (hereinafter referred to as a seal cap 38) made of, for example, stainless steel is detachably attached to the lower end opening of the manifold 117 so as to be hermetically sealed. A rotation means (hereinafter referred to as a rotation shaft 36) is connected to the seal cap 38, and the rotation shaft 36 rotates the substrate holding member (hereinafter referred to as the boat 21) and the plurality of wafers 200 held on the boat 21. Further, the seal cap 38 is connected to an elevating means (hereinafter referred to as a boat elevator 35) as a substrate conveying means, and elevates the boat 21. The boat elevator 35 conveys a plurality of wafers held in the boat 21 to the reaction space 34. The rotating shaft 36 and the boat elevator 35 are controlled by the control means 103 so as to have a predetermined speed.

  A heater 39 is coaxially disposed on the outer periphery of the outer tube 115. The heater 39 is controlled by the control means 103 so that the temperature in the outer tube 115 becomes a predetermined processing temperature. The inner tube 116, the outer tube 115, and the manifold 117 described above constitute a reaction space 34 for storing and processing the wafers 200 supported by the boat 21.

A plurality of film-forming gas nozzles 40 made of quartz are provided on one side of the manifold 117 from the reaction tube 37. By these film forming gas nozzles 40, a film forming gas is supplied into the inner tube 116. The film forming gas nozzle 40 is composed of a plurality of, for example, four quartz long nozzles A to D having different lengths (the lengths have a relationship of A>B>C> D). Here, the film forming gas nozzle 40 is constituted by four quartz long nozzles having different lengths, and the film thickness uniformity of the plurality of wafers 200 is ensured after the temperature gradient in the reaction furnace is made zero. For this purpose, the wafer array region 22 is divided into four zones, and a plurality of long nozzles are extended in the reaction furnace so as to correspond to the divided zones, and a film forming gas can be supplied from these. It is necessary.
The tips of the quartz long nozzles A to D are positioned in the wafer arrangement region 22 in the reaction space 34. In this case, the tip portions serving as the exits of the quartz long nozzles A to D are positioned so as to be displaced in the vertical direction along the wafer arrangement region 22, and the film forming gas is formed on the plurality of wafers 200 from midway in the wafer arrangement region 22. Are supplied evenly. Base end portions serving as inlets of these quartz long nozzles A to D are taken out of the reaction tube 37 through nozzle through holes formed on one side of the manifold 117.

Further, on the other side of the manifold 117, a quartz cleaning gas nozzle (hereinafter referred to as a ClF ₃ nozzle 46) that forms a cleaning gas supply port is provided. A cleaning gas is supplied into the inner tube 116 by the ClF ₃ nozzle 46. The tip of the ClF ₃ nozzle 46 is positioned below the wafer arrangement region 22. The base end portion of the ClF ₃ nozzle 46 is taken out of the reaction tube 37 through a nozzle through hole formed in the flange 117. Here, the ClF ₃ nozzle 46 is also made of quartz made of the same material as the quartz long nozzles A to D. However, the ClF ₃ nozzle 46 has a shorter length than the quartz long nozzles A to D, and is made of quartz. The damage problem at the time of cleaning like the long nozzles A to D does not occur so much.

  Further, a gas exhaust pipe 111 connected to an exhaust device (not shown) such as a vacuum pump is connected to the other side of the manifold 117, and a cylindrical space between the outer tube 115 and the inner tube 116 is connected. The control means 103 controls to discharge the gas flowing through 114 and bring the outer tube 115 into a reduced pressure atmosphere with a predetermined pressure.

The quartz long nozzles A to D and the ClF ₃ nozzle 46 described above are connected to a film forming gas source, an inert gas source, and a cleaning gas source (not shown) through a piping system.

In the quartz long nozzles A to D, the base end portions taken out of the reaction tube 37 are respectively air valves 79 to 82, two-way valves 51 to 54, air valves 75 to 78, flow control means (hereinafter referred to as MFC). ) It is connected to a film-forming gas source (not shown) (hereinafter referred to as SiH ₄ gas source) by piping through which 91-94 and air valves 71-74 are interposed. The two-way valves 51 to 54 are valves for switching the quartz long nozzles A to D side piping to the SiH ₄ gas source side piping or the non-film forming gas source side piping. Here, the non-film forming gas source side means an inert gas source side (hereinafter, N ₂ gas source) or a cleaning gas source (ClF ₃ gas source) side.

Further, the ClF ₃ nozzle 46 is connected to a ClF ₃ gas source (not shown) through a pipe having an air valve 89, a two-way valve 55, an air valve 84, an MFC 95, and an air valve 83 interposed therebetween. Here, the two-way valve 55 is a valve for switching the ClF ₃ gas source side piping to the ClF ₃ nozzle 46 side or the quartz long nozzles A to D side piping.

Further, a pipe between the two-way valve 55 and the air valve 84 interposed in the pipe on the ClF ₃ nozzle 46 side is connected to a pipe through which an air valve 86, an MFC 96, and an air valve 85 are interposed. It is connected to an N ₂ gas source (not shown). In addition, an air valve 88 is connected to a pipe in which four two-way valves 51 to 54 provided in a pipe on the film forming gas nozzle 40 side and a two-way valve 55 provided in a pipe on the ClF ₃ nozzle 46 side are connected in common. , MFC97, and a pipe through which an air valve 87 is interposed are connected, and the pipe is connected to the N ₂ gas source described above.

The control means 103 is a transport step for transporting a plurality of wafers 200 held in the boat 21 to the reaction space 34 by the boat elevator 35, and an exhaust pipe while supplying a film forming gas from the quartz long nozzles A to D to the reaction space 34. Control is performed to execute a film forming step for evacuating from 111 and forming a thin film on the wafer 200, and a cleaning step for removing the formed film deposited in the reaction tube 37 in the film forming step. The control means 103 controls the introduction of gas into the quartz long nozzles A to D and the ClF ₃ nozzle 46 in the film forming step and the cleaning step as follows.

During the film forming step, the control means 103 causes the two-way valves 51 to 51 provided in the pipe on the film forming gas nozzle 40 side so that the SiH ₄ gas source communicates with the quartz long nozzles A to D.
54 is switched to the quartz long nozzles A to D side, and the film forming gas whose flow rate is controlled by the MFC 91 to 94 is supplied to the reaction space 34 from the quartz long nozzles A to D.

In the cleaning step, the cleaning step is divided into a first cleaning step and a second cleaning step. In the first cleaning step, the inside of the reaction furnace 31 is maintained at the first condition by the control means 103. In addition, the two-way valves 51 to 54 provided in the piping on the film forming gas nozzle 40 side and the piping on the ClF ₃ nozzle 46 side so that the ClF ₃ gas source communicates with the quartz long nozzles A to D side piping. By switching the intervening two-way valve 55 to the film forming gas nozzle 40 side pipe at a predetermined timing, the cleaning gas (ClF ₃ gas) whose flow rate is controlled by the MFC 95 is supplied from the quartz long nozzles A to D. The reaction space 34 maintained at the first condition is supplied.

In the second cleaning step, the control means 103 maintains the inside of the reaction furnace 31 at a second condition different from the first condition, and the ClF ₃ gas source communicates with the ClF ₃ nozzle 46 side. By switching the two-way valve 55 provided in the pipe on the ClF ₃ nozzle 46 side to the ClF ₃ nozzle 46 side at a predetermined timing, the ClF ₃ gas whose flow rate is controlled by the MFC 95 is supplied from the ClF ₃ nozzle 46. It is supplied to the reaction space 34 held under a second condition different from the first condition.

Further, in the first cleaning step and the second cleaning step, the control means 103 controls the opening and closing of the air valves 86, 88 and the like provided in the pipe on the N ₂ gas source side at a predetermined timing. An inert gas whose flow rate is controlled by MFC 96 to 97 is supplied from the long nozzles A to D or the ClF ₃ nozzle 46 to the reaction space 34.

Next, an example of a semiconductor device manufacturing method using the above-described reaction furnace 31 will be described.
(1) Film formation step and operation related to film formation step First, the boat 21 is lowered by the boat elevator 35. A plurality of wafers 200 are held on the boat 21. Next, the temperature in the reaction space 34 is set to a predetermined processing temperature while being heated by the heater 39.
An inert gas whose flow rate is controlled by the MFC 97 is supplied into the reaction space 34 from the quartz long nozzles A to D, and the reaction space 34 is filled with the inert gas in advance. The boat 21 is lifted by the boat elevator 35 and moved into the reaction space 34, and the furnace port is hermetically closed by the seal cap 38. The internal temperature of the reaction space 34 is maintained at a predetermined processing temperature. At this time, the temperature gradient in the reaction space 34 formed by the heating control by the control means 103 of the heater 39 is flat, that is, zero. The reason for setting the temperature gradient to zero is to make the film quality and film thickness of the wafer having an influence on the temperature uniform.

  After evacuating the reaction space 34 to a predetermined vacuum state, the boat 21 and the plurality of wafers 200 held on the boat 21 are rotated by the rotating shaft 36. At the same time, the deposition gas whose flow rate is controlled by the MFC 91 to 94 is supplied from the quartz long nozzles A to D into the reaction space 34. The supplied gas rises in the reaction space 34 and is uniformly supplied to the plurality of wafers 200 arranged in the wafer arrangement region 22. The reaction space 34 during the low pressure CVD process is evacuated through the exhaust pipe 111, and the pressure is controlled by an automatic pressure controller (not shown) so as to obtain a predetermined vacuum, and the low pressure CVD process, ie, film formation for a predetermined time. Perform steps.

When the film forming step is completed in this manner, the gas in the reaction space 34 is replaced with an inert gas and the pressure is set to a normal pressure, and then the boat elevator 35 moves to proceed to the reduced pressure CVD processing of the next wafer 200. The boat 21 is lowered and the boat 21 and the processed wafer 200 are taken out from the reaction space 34. The processed wafer 200 on the boat 21 taken out from the reaction space 34 is replaced with an unprocessed wafer 200 and is again raised into the reaction space 34 in the same manner as described above to perform a low pressure CVD process.

  By the way, if the deposited film thickness of the inner wall of the reaction furnace 31 is, for example, 10 μm or more, it becomes a cause of generation of particles.

  This cleaning step is performed in two stages without lowering the furnace temperature to room temperature. In the first stage (first cleaning step), mainly the inner wall of the film forming gas nozzle 40 (quartz long nozzles A to D) is cleaned. In the second stage (second cleaning step), mainly the inner wall and the like of the reaction tube 37 are cleaned. Hereinafter, this will be specifically described with reference to FIG.

(2) First Cleaning Step The operation for cleaning the inner walls of the quartz long nozzles A to D will be described. In the present embodiment, this first cleaning step is performed prior to the second cleaning step of the inner wall of the reaction tube 37 and the like in order to prevent the quartz long nozzles A to D from devitrifying. In this case, the inside of the reaction furnace 31 is maintained at the first condition. The first condition is a condition in which the total flow rate of ClF ₃ gas that flows to the quartz long nozzles A to D in the first cleaning step is smaller than the total flow rate that flows from the ClF ₃ nozzle 46 in the second cleaning step. It is.

A ClF ₃ gas whose flow rate is controlled by the MFC 95 is introduced from the inlets of the quartz long nozzles A to D for film formation, and is supplied into the reaction tube 37 from the outlet. Thereby, the generated film deposited on the inner walls of the quartz long nozzles A to D is etched by the ClF ₃ gas. The etched product film is discharged into the reaction space 34 from the exits of the quartz long nozzles A to D. At this time, an evacuation process is performed. As a result, the formed film that has been etched and output to the reaction space 34 is discharged through the exhaust pipe 111.

As shown in FIG. 2, the cleaning process is performed by flowing a mixed gas of ClF ₃ and N ₂ with a small flow rate (blacked portion), and the four quartz long nozzles A to D are simultaneously performed here. In this case, since the lengths of the four quartz long nozzles A to D are different, the cleaning process is sequentially completed from the shorter quartz long nozzle D to the longer quartz long nozzle A. As described above, the control unit 103 controls the time during which the mixed gas of ClF ₃ and N ₂ is allowed to flow to each of the quartz long nozzles A to D. In this case, even after the cleaning is completed, N ₂ gas is continuously supplied from the quartz long nozzles A to D after the cleaning (white portion) so that the inert gas is supplied into the reaction space 34. . This prevents overetching of the quartz long nozzles A to D after the etching is completed.
That is, ClF ₃ gas usually remains in the quartz long nozzles A to D after the cleaning process. Therefore, if this is left as it is, the entire inner walls of the quartz long nozzles A to D are over-etched. However, in the present embodiment, the inert gas N ₂ is continuously supplied to the quartz long nozzles A to D after the cleaning process (white portion). Thereby, the ClF ₃ gas remaining in the quartz long nozzles A to D is expelled. Further, ClF ₃ gas discharged into the reaction space 34 from the quartz long nozzles A to D that have not been cleaned is prevented from flowing into the quartz long nozzles A to D that have been cleaned. As a result, overetching due to the remaining and inflow of ClF ₃ gas in the quartz long nozzles A to D is prevented.

In the first cleaning step, N ₂ gas is supplied into the reaction space 34 from the ClF ₃ nozzle 46. When an inert gas is supplied from the ClF ₃ nozzle 46, the concentration of the ClF ₃ gas supplied from the film forming gas nozzle 40 into the reaction space 34 can be adjusted. In addition, the ClF ₃ gas supplied from the film forming gas nozzle 40 into the reaction space 34 is changed to ClF ₃ nozzle 4.
Since it does not enter 6, extra devitrification of the ClF ₃ nozzle can be prevented.

(3) Second Cleaning Step Next, the operation for cleaning the inner wall and the like of the reaction tube 37 will be described. In the present embodiment, as shown in FIG. 2, the second cleaning step for cleaning the inner wall and the like of the reaction tube 37 has completed etching of the longest quartz long nozzle A among the quartz long nozzles A to D. Thereafter, a large flow rate of a mixed gas of ClF ₃ and N ₂ is continuously passed through the ClF ₃ nozzle (blacked portion). Here, in the second cleaning step, the outer walls of the quartz long nozzles A to D are also exposed to the ClF ₃ gas for the reaction furnace and cleaned in the same manner as the inner wall of the reaction tube 37. Here, the inside of the reaction furnace 31 is maintained under the second condition. The second condition is a condition in which the total flow rate flowing from the ClF ₃ nozzle 46 in the second cleaning step is larger than the total flow rate of ClF ₃ gas flowing to the quartz long nozzles A to D in the first cleaning step. It is.

A large flow rate of a mixed gas of ClF ₃ and N ₂ is introduced from the inlet of the ClF ₃ nozzle 46 for cleaning treatment, and is supplied into the reaction space 34 from the outlet. As a result, the formed film deposited on the inner wall of the reaction tube 37, the outer walls of the quartz long nozzles A to D and the ClF ₃ nozzle 46, and the like are etched. At this time, an evacuation process is executed. As a result, the etched product film is discharged through the exhaust pipe 111.

Further, in this case, as shown in FIG. 2, a small flow rate of inert gas N ₂ is continuously supplied into the reaction space 34 from all the quartz long nozzles A to D after the completion of the cleaning process (white coating portion). ). This is to prevent ClF ₃ gas from entering the quartz long nozzles A to D. That is, after removing the produced film in the quartz long nozzles A to D, when removing the produced film in the reaction furnace under the second condition, a large flow rate of ClF ₃ gas enters the quartz long nozzles A to D. Therefore, there is a concern that it may adversely affect the next film formation. For this reason, when removing the generated film such as the inner wall of the reaction furnace, the inflow of ClF ₃ gas is prevented by flowing a small flow rate of N ₂ gas through the quartz long nozzles A to D.

The specific conditions of the film forming step and the cleaning step described above are as follows. The film type here is a polysilicon film (that is, a flat polysilicon film), the film forming gas is SiH ₄ , and the cleaning gas is a mixed gas of ClF ₃ gas and N ₂ (hereinafter referred to as ClF ₃ + N ₂ ). N ₂ is an inert gas that dilutes the cleaning gas.
[Deposition step conditions]
Reactor capacity: 300-500L
Deposition temperature: 600-700 ° C
Reactor pressure: 10-100 Pa
Wafer diameter: 30cm
Number of wafers inserted into the reactor: 100 Wafer arrangement area height: 1 to 1.2 m
Flow through all quartz long nozzles A to D (SiH ₄ ) Total flow rate: 0.04 to 1.2 SLM
Flow through each quartz long nozzle A to D (SiH ₄ ): 0.01 to 0.3 SLM

[First condition in first cleaning step]
Flow through all quartz long nozzles A to D (ClF ₃ + N ₂ ) Total flow rate: 0.02 to 6 SLM
Total flow rate of ClF ₃ flowing through all quartz long nozzles A to D: 0.01 to 2 SLM
N ₂ total flow rate flowing through all quartz long nozzles A to D: 0.01 to 4 SLM
(ClF ₃ + N ₂ ) flow through each quartz long nozzle A to D: 0.005 to 1.5 SLM
ClF ₃ flow rate flowing through each quartz long nozzle A to D: 0.0025 to 0.5 SLM
N ₂ total flow rate flowing through each quartz long nozzle A to D: 0.0025 to 1 SLM
N ₂ flow rate to flow through ClF ₃ nozzle: 0.1-1 SLM
N ₂ flow rate to flow to each quartz long nozzle A to D after cleaning: 0.01 to 1 SLM
Cleaning time: 5min-30min

The completion of cleaning of each quartz long nozzle A to D and the timing of flowing N ₂ gas thereafter depend on the thickness of the polysilicon film, but the length of the nozzle is nozzle A> nozzle B> nozzle C> nozzle. Since D, cleaning is completed in the order of nozzle D → nozzle C → nozzle B → nozzle A, and N ₂ gas is allowed to flow.

[Second condition in second cleaning step]
Flow through ClF ₃ nozzle (ClF ₃ + N ₂ ) Total flow rate: 1.1 to 11 SLM
ClF ₃ flow into the nozzle _(ClF 3 + _{N 2)} ClF ₃ flow rate of the total flow rate: 0.1～1SLM
ClF ₃ flow into the nozzle _{(ClF 3 + N 2) N} 2 flow rate of the total flow rate: 1～10SLM
Cleaning time: 1 to 3 hours (hours)
N ₂ flow rate flowing through each quartz long nozzle A to D: 0.01 to 0.1 SLM
(Common conditions for the first condition and the second condition)
Temperature: 300-500 ° C
Reactor pressure: 10 to 200 Pa
ClF ₃ concentration: 10-50%

As described above, according to the present embodiment, the mixed gas flow rate of ClF ₃ and N ₂ in the first cleaning step is smaller than the mixed gas flow rate in the second cleaning step (1/50 to 1 / Therefore, damage to the quartz long nozzles A to D can be reduced in the first cleaning step. Therefore, it is possible to extend the time for exchanging the quartz long nozzle, which has been conventionally performed every time the inside of the reaction tube 37 is cleaned. As a result, the cost for maintenance of the CVD apparatus can be greatly reduced. In addition, the time required for exchanging the quartz long nozzle can be reduced, and the downtime of the reactor can be shortened.

Further, in the first cleaning step, a mixed gas of ClF ₃ and N ₂ having a smaller flow rate than that in the second cleaning step is supplied from the quartz long nozzles A to D having a length longer than that of the ClF ₃ nozzle 46. Therefore, the polysilicon film deposited in the quartz long nozzles A to D can be effectively removed without damaging the quartz long nozzles A to D. At this time, is an inert gas N ₂ is supplied to the cleaning completion quartz long nozzle to D, since ClF ₃ gas remaining inside the quartz long nozzle to D is evicted, over by ClF ₃ gas remaining etching Can be prevented. The cleaning ClF ₃ gas, which is discharged into the reaction space 34 from the quartz long nozzle to D that has not ended is, since it is prevented from entering the cleaning after the end of the quartz long nozzle to D, ClF ₃ Overetching at the tips of the inner walls of the quartz long nozzles A to D due to gas intrusion can be prevented.

In the first cleaning step, the cleaning gas supply time is changed in accordance with the lengths of the plurality of quartz long nozzles A to D having different lengths. Appropriate etching can be performed without causing damage such as etching.
In particular, in the embodiment, a flat polysilicon film is formed by supplying a film forming gas into the reaction furnace from a plurality of quartz long nozzles A to D having different lengths while setting the temperature gradient in the reaction furnace to zero. However, in the present invention, when etching the generated film deposited on the inner walls of the quartz long nozzles A to D having different lengths used when forming such a flat polysilicon film, Since the quartz long nozzles A to D are susceptible to damage due to their shapes, they are particularly useful.

In the second cleaning step, a mixed gas of ClF ₃ and N ₂ having a larger flow rate than that in the first cleaning step is supplied from the ClF ₃ nozzle 46 into the reaction tube 37. The polysilicon film deposited on the substrate can be effectively removed. Further, as a cleaning gas nozzle for cleaning the inside of the reaction tube 37, a ClF ₃ nozzle 46 different from the film forming gas nozzle 40 is used, and N ₂ gas can be supplied from the quartz long nozzles A to D. In the second cleaning step, ClF ₃ gas can be prevented from entering the quartz long nozzles A to D. Therefore, overetching in the quartz long nozzles A to D due to the intrusion of ClF ₃ gas can be prevented.

  In the embodiment, the nozzle cleaning is performed first and the reaction tube cleaning is performed later. On the contrary, the reaction tube cleaning may be performed first. However, after the nozzle cleaning, the amount of cleaning gas is reduced in the nozzle cleaning step, so that the formed film etched from the inner wall of the nozzle cannot be effectively discharged from the reaction tube and accumulates at the bottom of the reaction tube, and particles are collected. There are concerns about the occurrence. Therefore, it is preferable to perform cleaning in the order of the embodiment without such a concern.

  In the embodiment, the case where the polysilicon film is subjected to the cleaning process has been described. However, the present invention is not limited to this, and the present invention can also be applied to the case where another film type is subjected to the cleaning process. In the embodiment, the case where four film forming gas nozzles are used has been described. However, the number of film forming gas nozzles is not limited to four.

In the embodiment, when a polysilicon film is formed on the substrate using SiH ₄ and the polysilicon film deposited in the reaction tube or the nozzle in the film forming process is cleaned, the polysilicon is used as a cleaning gas. Since ClF ₃ which is most effective for etching the silicon film is used, the polysilicon film deposited on the inner wall of the deposition gas nozzle and the inner wall of the reaction tube can be effectively removed. The cleaning gas of the present invention is not limited to ClF ₃ , and other cleaning gases such as NF ₃ and F ₂ can also be used.

  In the embodiment, the case where a plurality of film forming gas nozzles are simultaneously cleaned has been described. However, the plurality of film forming gas nozzles are sequentially selected one by one in accordance with a predetermined order, so that each one is performed. It may be.

In the embodiment, the total flow rate of the cleaning gas is used as the parameter as the first and second conditions, but the present invention is not limited to this. For example, the cleaning gas concentration may be used as a parameter. In this case, it is preferable that the concentration of the cleaning gas (ClF ₃ or the like) is smaller in the first cleaning step than in the second cleaning step. By doing so, the polysilicon film deposited in the quartz long nozzles A to D can be effectively removed without damaging the quartz long nozzles A to D. The gas concentration is determined by changing the flow rate of dilution gas N ₂ or ClF ₃ . In this case, both the gas concentration and the gas flow rate can be used as parameters, or only the gas concentration can be used as a parameter.

Further, in the embodiment, the case where the second cleaning step (reaction tube cleaning) is performed after the first cleaning step (nozzle cleaning) has been described. However, the first cleaning step and the second cleaning step are performed simultaneously. It is also possible to do this. In this case, the cleaning gas set to the first condition is supplied from the film forming gas nozzle, and the cleaning gas set to the second condition different from the first condition is supplied from the ClF ₃ nozzle. The first condition, the second condition, the supply of N ₂ to the deposition gas nozzle after the cleaning, and the like are the same as in the embodiment.
As described above, if the first cleaning step and the second cleaning step are performed simultaneously, the cleaning time can be shortened in total.

  In the embodiment, the case of a multi-system nozzle that is particularly effective has been described. However, the present invention can also be applied to the case of a single-system nozzle. Moreover, although the case of the film-forming gas nozzles having different lengths has been described, the present invention can also be applied to the case of having film-forming gas nozzles having the same length.

A flat polysilicon film was formed using the vertical CVD apparatus shown in FIG. 1, and then cleaning with ClF ₃ gas was performed. In the first cleaning step, as a first condition, N ₂ for dilution is set so that the ClF ₃ gas has a concentration of 28.6% in the quartz long nozzles A to D at a furnace temperature of 400 ° C. The gas was mixed and flowed, and cleaning was performed at a total mixed gas flow rate of 0.7 SLM (ClF ₃ : 0.2 SLM, N ₂ : 0.5 SLM). This total flow rate is about 1/3 of the second condition described later. As a result, it was confirmed that the cleaning in the quartz long nozzles A to D can be performed while minimizing damage.
Note that the etching rate under this condition, that is, the ClF ₃ concentration of 28.6% and the mixed gas total flow rate 0.7 SLM (ClF ₃ : 0.2 SLM, N ₂ : 0.5 SLM) is the same concentration and the total mixed gas flow rate. It has been confirmed that the etching rate is 4.7 times as high as 0.07 SLM (ClF ₃ : 0.02 SLM, N ₂ : 0.05 SLM).

Further, as the second cleaning step, the second condition is that the furnace temperature is 400 ° C. and the ClF ₃ gas is diluted to a concentration of 28.6% in the ClF ₃ nozzle 46. The N ₂ gas was mixed and flowed, and cleaning was performed at a total mixed gas flow rate of about 2.5 SLM. Thus, it was confirmed that the ClF ₃ gas cleaning can effectively clean the inner wall of the reaction furnace, and can suppress damage in the quartz long nozzles A to D.

The first cleaning step flow into the quartz long nozzle and ClF ₃ nozzles after completion of the cleaning in the N ₂ gas flow, and the flow rate of N ₂ gas to flow into the quartz long nozzle in the second cleaning step, both 0. 02SLM. As a result, it was confirmed that there was no adverse effect during the formation of the next flat polysilicon film, damage to the nozzle such as overetching, and the nozzle was not devitrified.

21 Boat (substrate holding member)
31 Reaction furnace 40 Deposition gas nozzles 41 to 44 Quartz long nozzle (deposition gas nozzle)
46 ClF ₃ nozzle (cleaning gas nozzle)
200 wafer (substrate)

Claims (8)

Carrying the substrate into the reactor;
Supplying a film forming gas into the reactor from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate;
Unloading the substrate after film formation from the reactor;
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles, and cleaning is sequentially completed from a shorter film forming gas nozzle to a longer film forming gas nozzle among the plurality of film forming gas nozzles. In addition, the inert gas is supplied to the film forming gas nozzle that has been cleaned,
In the second cleaning step, in a state where an inert gas is supplied into the plurality of film forming gas nozzles, a cleaning gas is supplied from the cleaning gas supply port ,
The total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is larger than the flow rate of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. A method for manufacturing a semiconductor device, characterized in that the semiconductor device is made smaller . Carrying the substrate into the reactor;
Supplying a film forming gas into the reactor from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate;
Unloading the substrate after film formation from the reactor;
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, a cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles while an inert gas is supplied from the cleaning gas supply port, and a shorter one of the plurality of film forming gas nozzles is formed. The cleaning is sequentially completed from the film gas nozzle to the longer film forming gas nozzle, and the inert gas is supplied to the film forming gas nozzle after the cleaning,
In the second cleaning step, in a state where an inert gas is supplied into the plurality of film forming gas nozzles, a cleaning gas is supplied from the cleaning gas supply port ,
The total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is larger than the flow rate of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. A method for manufacturing a semiconductor device, characterized in that the semiconductor device is made smaller . Carrying the substrate into the reactor;
Supplying a film forming gas into the reactor from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate;
Unloading the substrate after film formation from the reactor;
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles, and cleaning is sequentially completed from a shorter film forming gas nozzle to a longer film forming gas nozzle among the plurality of film forming gas nozzles. And supplying an inert gas to the film forming gas nozzle after cleaning,
In the second cleaning step, in a state where an inert gas is supplied into the plurality of film forming gas nozzles, a cleaning gas is supplied from the cleaning gas supply port,
The concentration of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is the same as the concentration of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. And the total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is supplied into the reaction furnace from the cleaning gas supply port in the second cleaning step. A method of manufacturing a semiconductor device, wherein the flow rate is smaller than a flow rate of a cleaning gas. Carrying the substrate into the reactor;
Supplying a film forming gas into the reactor from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate;
Unloading the substrate after film formation from the reactor;
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, a cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles while an inert gas is supplied from the cleaning gas supply port, and a shorter one of the plurality of film forming gas nozzles is formed. The cleaning is sequentially completed from the film gas nozzle to the longer film forming gas nozzle, and the inert gas is supplied to the film forming gas nozzle after the cleaning,
In the second cleaning step, an inert gas is supplied into the plurality of film forming gas nozzles.
In the supplied state, the cleaning gas is supplied from the cleaning gas supply port,
The concentration of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is the same as the concentration of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. And the total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is supplied into the reaction furnace from the cleaning gas supply port in the second cleaning step. method of manufacturing a semi-conductor device you characterized in that set to be smaller than the flow rate of the cleaning gas. A cleaning method for cleaning the inside of the plurality of film forming gas nozzles and the inside of the reaction furnace after supplying a film forming gas into the reaction furnace from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate There,
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles, and cleaning is sequentially completed from a shorter film forming gas nozzle to a longer film forming gas nozzle among the plurality of film forming gas nozzles. And supplying an inert gas to the film forming gas nozzle after cleaning,
In the second cleaning step, in a state where an inert gas is supplied into the plurality of film forming gas nozzles, a cleaning gas is supplied from the cleaning gas supply port,
The total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is larger than the flow rate of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. A cleaning method characterized by reducing the size. A cleaning method for cleaning the inside of the plurality of film forming gas nozzles and the inside of the reaction furnace after supplying a film forming gas into the reaction furnace from a plurality of film forming gas nozzles having different lengths to form a thin film on the substrate There,
A first cleaning step of supplying a cleaning gas into the plurality of film forming gas nozzles to remove a generated film deposited in the plurality of film forming gas nozzles;
A second cleaning step of supplying a cleaning gas from a cleaning gas supply port different from the film forming gas nozzle into the reaction furnace to remove a formed film deposited in the reaction furnace,
In the first cleaning step, a cleaning gas is simultaneously supplied into the plurality of film forming gas nozzles while an inert gas is supplied from the cleaning gas supply port, and a shorter one of the plurality of film forming gas nozzles is formed. The cleaning is sequentially completed from the film gas nozzle to the longer film forming gas nozzle, and the inert gas is supplied to the film forming gas nozzle after the cleaning,
In the second cleaning step, in a state where an inert gas is supplied into the plurality of film forming gas nozzles, a cleaning gas is supplied from the cleaning gas supply port,
The total flow rate of the cleaning gas supplied into the plurality of film forming gas nozzles in the first cleaning step is larger than the flow rate of the cleaning gas supplied into the reactor from the cleaning gas supply port in the second cleaning step. A cleaning method characterized by reducing the size. A reactor containing the substrate;
A plurality of film forming gas nozzles having different lengths for supplying a film forming gas into the reaction furnace;
A cleaning gas supply port provided separately from the film forming gas nozzle, for supplying a cleaning gas into the reaction furnace;
Supplying a cleaning gas into the plurality of film forming gas nozzles to remove a formed film deposited in the plurality of film forming gas nozzles, and supplying a cleaning gas into the reaction furnace from the cleaning gas supply port And a second cleaning for removing the formed film deposited in the reaction furnace, and in the first cleaning, a cleaning gas is simultaneously supplied into the plurality of film-forming gas nozzles, and the plurality of components are formed. Among the film gas nozzles, cleaning is sequentially completed from a shorter film formation gas nozzle to a longer film formation gas nozzle, and an inert gas is supplied to the film formation gas nozzle that has been cleaned. 2, the cleaning gas is supplied with an inert gas supplied into the plurality of film forming gas nozzles. It controls the introduction of the cleaning gas and the inert gas so as to supply the cleaning gas from the supply port, the total flow rate of the cleaning gas supplied to the said plurality of the film forming gas nozzles in the first cleaning, second Control means for controlling the flow rate of the cleaning gas so as to be smaller than the flow rate of the cleaning gas supplied into the reactor from the cleaning gas supply port in the cleaning ;
A substrate processing apparatus comprising: A reactor containing the substrate;
A plurality of film forming gas nozzles having different lengths for supplying a film forming gas into the reaction furnace;
A cleaning gas supply port provided separately from the film forming gas nozzle, for supplying a cleaning gas into the reaction furnace;
Supplying a cleaning gas into the plurality of film forming gas nozzles to remove a formed film deposited in the plurality of film forming gas nozzles, and supplying a cleaning gas into the reaction furnace from the cleaning gas supply port And performing a second cleaning for removing the formed film deposited in the reaction furnace, and in the first cleaning, the plurality of components are formed while an inert gas is supplied from the cleaning gas supply port. The cleaning gas is supplied into the film gas nozzle at the same time, and the cleaning is sequentially completed from the shorter film forming gas nozzle to the longer film forming gas nozzle among the plurality of film forming gas nozzles. An inert gas is supplied to the deposition gas nozzle, and in the second cleaning, the plurality of deposition gases are supplied. While supplying an inert gas into the nozzle, to control the introduction of the cleaning gas and the inert gas so as to supply the cleaning gas from the cleaning gas supply port, said plurality of film deposition gas nozzles in the first cleaning Control means for controlling the flow rate of the cleaning gas so that the total flow rate of the cleaning gas supplied into the reactor becomes smaller than the flow rate of the cleaning gas supplied into the reaction furnace from the cleaning gas supply port in the second cleaning. ,
A substrate processing apparatus comprising:

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