JP2005197561A - Substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent problems of corrosion of piping or the like in a film formation method of a silicon oxide film by an ALD method and a film formation apparatus of a silicon oxide film by the ALD method. <P>SOLUTION: The manufacturing method and the manufacturing apparatus of a semiconductor device are provided, wherein for forming a silicon oxide film uniform and conformal at a low processing temperature of ≤500°C triethoxysilane and active oxygen such as ozone are alternately supplied into a processing chamber to form the silicon oxide film on the substrate. Further, triethoxysilane and ozone (O<SB>3</SB>), oxygen (O<SB>2</SB>), N<SB>2</SB>O or the like as processing gases, i.e., gases not involving Cl atoms are employed, so that problems such as corrosion of piping or the like are not created. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a method for manufacturing a semiconductor device, for example, a semiconductor integrated circuit device (hereinafter referred to as IC,
It is called a semiconductor device. In the manufacturing method of (1), the present invention relates to an effective technique that is used in an oxide film forming step of forming an oxide film and a nitride film by CVD on a substrate such as a semiconductor wafer (hereinafter referred to as a wafer) in which an IC is formed.

In the past, silicon nitride films have been frequently used in IC components, but in order to lower the dielectric constant, a laminated structure of a silicon oxide film and a nitride film is often used.
These silicon oxide films and nitride films have recently been reduced to 500 ° C as the minimum processing dimensions of ICs have been reduced.
It must be formed at the following low processing temperature.

For devices with complex shapes, it has been studied to form a film by the ALD method in order to ensure step coverage. Until now, a film forming temperature of 300 ° C. or less has been used for TCS (SiCl ₄ ).
It has been reported that a film is formed by an ALD (Atomic Layer Deposition) method using H ₂ O. However, when TCS, which is a chloride, reacts with water (H ₂ O),
HCl may be formed, which may corrode the exhaust system piping.

On the other hand, Si-based organometallic (MO) raw material and chlorine containing no H ₂ O
Alternatively, an ALD method using an oxidizing agent such as oxygen or ozone has been studied. However, the film formed by the ALD method at a low temperature of 300 ° C or less contains a large amount of Cl component in the chloride raw material, C and H component in the MO raw material, and is mixed as an impurity in the semiconductor device to be manufactured. There is a problem of deteriorating the characteristics of semiconductor devices.

Accordingly, an object of the present invention is to perform chemical vapor deposition of a silicon oxide film on a substrate such as a wafer at a low temperature using a silicon raw material.

In order to solve the above-described problems, the present invention provides a processing chamber for storing and processing a substrate, and first supplying triethoxysilane (hereinafter referred to as TRIE) as a processing gas to the processing chamber. A substrate processing apparatus comprising: a gas supply means; and a second gas supply means for supplying ozone as a second processing gas into the processing chamber, wherein the first processing gas and the second processing gas are supplied to the processing chamber. The substrate processing apparatus is characterized in that the substrate is processed alternately by being supplied into the processing chamber.

Further, the present invention provides a substrate carry-in step for carrying a substrate into a processing chamber, a first gas supply step for supplying TRIE as a first processing gas to the processing chamber, and a first processing gas from the processing chamber. A first exhaust process for exhausting, a second gas supply process for supplying ozone as a second process gas to the process chamber, and a second exhaust process for exhausting the second process gas from the process chamber. A method for manufacturing a semiconductor device is provided.

The present invention relates to a silicon oxide film forming method by an ALD method and a silicon oxide film forming apparatus by an ALD method. In particular, in order to form a homogeneous and conformal silicon oxide film at a low processing temperature of 500 ° C. or lower, TRIES and active oxygen such as ozone are alternately supplied to the processing chamber to form a silicon oxide film on the substrate. The present invention relates to a semiconductor device manufacturing method and a manufacturing apparatus. Further, in the present invention, TRIES and ozone (O ₃ ), oxygen (O ₂ ), N ₂ O, etc. are used as the processing gas, and since a gas not containing Cl atoms is used, there is a problem such as pipe corrosion. It does not occur.

A substrate processing apparatus according to the present invention includes an IO port for transferring a cassette in which a substrate is stored with the outside of the apparatus, a substrate transfer machine for loading and unloading the substrate in the cassette into a processing furnace,
It consists of a processing furnace that accommodates and processes substrates. Hereinafter, a processing furnace will be described in the substrate processing apparatus according to the embodiment of the present invention.

[Example 1]
FIG. 1 is a schematic view showing a processing furnace of a substrate processing apparatus in an embodiment of the present invention. In this embodiment, ozone is used as the oxidizing agent. FIG. 1 shows a processing furnace 10 for receiving and processing wafers.
1; a TRIES supply unit that supplies triethoxysilane (SiH (OC ₂ H ₅ ) ₃ , hereinafter referred to as TRIES) into the processing chamber 52; an ozone supply unit that supplies ozone into the processing chamber 52; Processing chamber 52
It is divided into an exhaust part for exhausting the atmosphere inside and a control part.

The processing furnace 101 heats an inner wall of the processing chamber 52, a processing chamber 52 that can be decompressed, a substrate support 12 that supports a substrate in the processing chamber, a heater 3 that heats the processing chamber to a processing temperature, and the processing chamber 52. An inner wall heater 21 to perform, an inert gas supply pipe 6 for supplying an inert gas,
It has a valve 36 and a flow rate controller 33 as flow rate control means for controlling the flow rate of the inert gas.

The output of the heater 3 is controlled by the control unit so that the temperature of the substrate 1 becomes a predetermined temperature, for example, 300 ° C. to 500 ° C. The inner wall heater 21 heats the inner wall of the processing chamber 52, and the liquid TRIES does not re-liquefy and adhere at normal temperature and pressure, and further, a temperature at which a sealing material such as an O-ring is not deteriorated, for example, 80 ° C. to 180 ° C. The output is controlled by the control means.

  In this embodiment, argon is used as the inert gas.

The TRIES supply unit is a TRIES supply pipe 4, a TRIES supply pipe 10 for introducing TRIES from the TRIES supply apparatus 4 to the processing chamber 52, a valve 34, and a TRIES supply pipe heater for heating the TRIES supply pipe 10. 22.

Since TRIES is a liquid at room temperature and normal pressure, the TRIES feeder 4 supplies TRIE to a predetermined temperature, for example 70
Vaporize by heating to ~ 100 ° C. The TRIES feeder 4 of this embodiment has a flow rate control means built-in so as to perform the flow rate of TRIES. Note that a separate flow rate control unit may be provided in the middle of the TRIE supply pipe 10 so that the TRIE supply unit 4 does not include the flow rate control unit.

The TRIES vaporized by the TRIE feeder 4 passes through the TRIES supply pipe 10 to the processing chamber 5.
2 is supplied. The TRIES supply pipe 10 is heated to a predetermined temperature, for example, 70 to 100 ° C. or more by the TRIES supply pipe heater 22 so that the vaporized TRIES does not re-liquefy.

The ozone supply unit includes an ozone generator 5, an ozone supply pipe 11 for introducing ozone from the ozone generator 5 into the processing chamber 52, a flow rate controller 32 as a flow rate control means for controlling the flow rate of the ozone, A valve 35, an oxygen supply pipe 30 for supplying oxygen (O ₂ ) as a raw material of ozone to the ozone generator 5, and nitrogen (N ₂ ) used for generating ozone are supplied to the ozone generator 5. A nitrogen supply pipe 31 is provided.

Ozone uses oxygen and nitrogen supplied from the oxygen supply pipe 30 and the nitrogen supply pipe 31,
It is generated by the ozone generator 5. In this embodiment, the supply ratio of oxygen and nitrogen is supplied at a ratio of 100: 1, for example, oxygen 6 slm and nitrogen 60 ccm. The ozone concentration produced is about 170 g / m3.

The exhaust unit includes a vacuum pump 8 serving as an exhaust unit for reducing the pressure in the processing chamber 52, and the processing chamber 52.
And an exhaust pipe 7 for connecting the vacuum pump 8, a valve 37, a pressure control means 38 for controlling the pressure in the processing chamber 52, and an exhaust pipe heater 20 for heating the exhaust pipe 7.
The exhaust pipe heater 20 has a temperature at which TRIES flowing through the exhaust pipe 7 does not re-liquefy, and further, the output by the control means so that the seal material such as an O-ring is not deteriorated, for example, 80 ° C. to 180 ° C. Is controlled.

The control unit includes a control device 9. The control unit 9 includes a heater 3, an inner wall heater 21, TR
The temperature of the IES supply pipe heater 22 and the exhaust pipe heater 20 and the flow rate controllers 32, 3
3 and the pressure control means 37 are controlled.

[Example 2]
FIG. 2 is a schematic configuration diagram of the vertical processing furnace 101 according to the present embodiment, and shows the processing furnace part in a vertical cross section. A reaction tube 2 is provided as a reaction vessel for processing the substrate (wafer) 1 inside a heater 3 which is a heating means for heating the substrate 1, and the lower end opening of the reaction tube 2 is hermetically sealed by a seal cap 111 which is a lid. The processing chamber 52 is formed by being hermetically closed through an O-ring 110 that is a member. At least the heater 3, the reaction tube 2, and the seal cap 1
11, the processing furnace 101 is formed. The seal cap 111 has a quartz cap 116.
A boat 115 serving as a substrate holding means is erected through the quartz cap 116, and the quartz cap 116 serves as a holding means for holding the boat 115. Then, the boat 115 is inserted into the processing furnace 101. A plurality of wafers 1 to be batch-processed are stacked on the boat 115 in a horizontal posture in multiple stages in the tube axis direction. The heater 3 heats the wafer 1 inserted into the processing furnace 101 to a predetermined temperature.

Then, TRIE is used as a supply pipe for supplying a plurality of types of gases into the processing chamber 52, here two types of gases.
An S supply pipe 10 and an ozone supply pipe 11 are provided. Here, the processing gas enters the processing chamber 52 from the TRIES supply pipe 10 through a flow rate controller 41 as a flow rate control means and a valve 34 as an on-off valve, and further through a nozzle 113 installed in the processing chamber 52 described later. Is supplied.
From the ozone supply pipe 11, a flow rate controller 32 which is a flow rate control means and a valve 35 which is an on-off valve.
The processing gas is supplied to the processing chamber 52 through a nozzle 114 which will be described later.

An exhaust pipe 20, which is an exhaust pipe for exhausting the atmosphere (gas) in the processing chamber 52, is provided in the processing chamber 52.
Is connected to a vacuum pump 8 as an exhaust means through a valve 42 so that the inside of the processing chamber 52 can be evacuated. The valve 42 opens and closes the processing chamber 5 by opening and closing the valve.
2 can be evacuated and stopped, and the pressure can be adjusted by adjusting the valve opening. In the present embodiment, the valve 43 is a valve capable of adjusting the pressure. However, as shown in FIG. 1 of the first embodiment, the valve 43 that is an on-off valve for stopping evacuation / evacuation of the processing chamber 52 and the pressure You may install separately in the pressure control part 38 which is a control means.

Inside the reaction tube 2 constituting the processing chamber 52, a nozzle 113 is erected from the lower part of the reaction tube 2 along the inner wall of the reaction tube (in the loading direction of the wafer 1). The nozzle 113 is provided with supply holes for supplying a plurality of gases. When the pressure difference between the supply hole and the processing chamber 52 is small, the opening area of the supply hole is preferably increased from the upstream side toward the downstream side or the opening pitch is decreased.

Further, the nozzle 11 is positioned along the inner wall of the reaction tube (along the loading direction of the wafer 1) at a position rotated about 120 ° from the position of the nozzle 113 along the inner periphery of the reaction tube 2.
4 is installed. Similarly, the nozzle 114 is provided with supply holes which are supply holes for supplying a plurality of gases.

A boat 115 on which a plurality of wafers 1 are placed in multiple stages at the same interval is provided in the center of the reaction tube 2 so that the boat 115 can enter and exit the reaction tube 2 by a boat elevator mechanism (not shown). It has become. Further, in order to improve the uniformity of processing, a boat rotation mechanism 112 which is a rotation means for rotating the boat 115 is provided. By rotating the boat rotation mechanism 112, the boat 115 held by the quartz cap 116 is removed. It is designed to rotate.

The control device 9 serving as a control means includes flow rate controllers 23, 33, 41, valves 34, 35, 36.
, 42, heater 3, exhaust pipe heater 20, TRIE supply pipe heater 22, ozone supply pipe heater 24, vacuum pump 8, boat rotation mechanism 112, boat lifting mechanism not shown in the figure, and flow control Flow rate adjustment of the devices 23, 33, 41, valves 34, 35,
36, 42 open / close operation, exhaust pipe heater 20, TRIE supply pipe heater 22,
Adjustment of the output of the ozone supply pipe heater 24, start / stop of the vacuum pump 8, adjustment of the rotational speed of the boat rotation mechanism 112, control of the lifting / lowering operation of the boat lifting / lowering mechanism, and the like are performed.

[Example 3]
3 and 4 are schematic configuration diagrams of the vertical processing furnace 101 according to the present embodiment. FIG. 3 shows a vertical cross section of the processing furnace 101, and FIG. 4 shows a cross section of the processing furnace 101. A reaction tube 2 is provided as a reaction vessel for processing the wafer 1 as a substrate inside a heater 3 as a heating means, and the lower end opening of the reaction tube 2 is an O-ring as an airtight member by a seal cap 111 as a lid. 1
10 is sealed in an airtight manner, and a processing chamber 52 is formed. A processing furnace 101 is formed by at least the heater 3, the reaction tube 2, and the seal cap 111. A boat 115 as a substrate holding means is erected on the seal cap 111 via a quartz cap 116, and the quartz cap 116 serves as a holding means for holding the boat 115. Then, the boat 115 is inserted into the processing furnace 101. A plurality of wafers 1 to be batch-processed are stacked on the boat 115 in a horizontal posture in multiple stages in the tube axis direction. The heater 3 heats the wafer 1 inserted into the processing furnace 101 to a predetermined temperature.

As a supply pipe for supplying a plurality of types of processing gases to the processing chamber 52, here two types of processing gases
A TRIES supply pipe 10 and an oxygen supply pipe 213 are provided. Here, TRIES supply pipe 10
The processing gas is supplied to the processing chamber 52 through a flow rate controller 41 as a flow rate control means and a valve 34 as an on-off valve, and further through a buffer chamber 212 installed in the processing chamber 52 described later. A processing gas is supplied from the oxygen supply pipe 213 into the processing chamber 52 through a flow rate controller 32 that is a flow rate control unit, a valve 35 that is an on-off valve, and a gas supply unit 216 that will be described later.

An exhaust pipe 20, which is an exhaust pipe for exhausting the atmosphere (gas) in the processing chamber 52, is provided in the processing chamber 52.
Is connected to a vacuum pump 8 as an exhaust means through a valve 42 so that the inside of the processing chamber 52 can be evacuated. The valve 42 opens and closes the processing chamber 5 by opening and closing the valve.
2 can be evacuated and stopped, and the pressure can be adjusted by adjusting the valve opening. In the present embodiment, the valve 43 is a valve capable of adjusting the pressure. However, as shown in FIG. 1 of the first embodiment, the valve 43 that is an on-off valve for stopping the vacuum evacuation / evacuation of the processing chamber 52 and the pressure You may install separately in the pressure control part 38 which is a control means.

Inside the reaction tube 2 constituting the processing chamber 52, a buffer chamber 212 which is a gas dispersion space is provided from the lower part of the reaction tube 2 along the inner wall of the reaction tube (along the loading direction of the wafer 1). The buffer chamber 212 is provided at the end of the wall adjacent to the wafer 1 in the buffer chamber 212.
A gas supply hole 211 that is a supply hole for supplying a processing gas is provided therein. The gas supply holes 211 have the same opening area from the lower part to the upper part, and are provided at the same opening pitch.

A plurality of gas supply holes 214 for supplying the processing gas in the buffer chamber 212 are provided in the processing chamber 52 on the wall constituting the buffer chamber 212. This gas supply hole 214 is connected to the reaction tube 2
Open towards the center of the. When the differential pressure between the buffer chamber 212 and the processing chamber 52 is small, the gas supply hole 214 may have the same opening area from the upstream side to the downstream side with the same opening pitch. If it is larger, the opening area should be increased from the upstream side toward the downstream side, or the opening pitch should be reduced.

In the present invention, since the opening area and opening pitch of the gas supply holes 214 are adjusted from the upstream side to the downstream side, there is a difference in gas flow velocity from each supply port of the gas supply hole 211, but the flow rate is almost the same amount. Erupt. Then, the processing gas ejected from each gas supply hole of the gas supply hole 211 is ejected into the buffer chamber 212 and once introduced, and the flow velocity difference of the gas is made uniform. That is, the processing gas ejected from the gas supply hole 211 in the buffer chamber 212 is ejected into the processing chamber 52 from the gas supply hole 214 after the particle velocity of each gas is relaxed in the buffer chamber 212. In this way, when a processing gas having a difference in flow velocity or the like ejected from the gas supply hole 211 is ejected from each gas supply hole of the gas supply hole 214, a gas having a uniform flow rate and flow velocity is obtained. can do.

Further, a first rod-like electrode 2 that is a first electrode having an elongated structure is provided in the buffer chamber 212.
30 and a second rod-shaped electrode 231 which is a second electrode are disposed protected by electrode protection tubes 218 and 220 which are protective tubes for protecting the electrode from the upper part to the lower part, and this first rod-shaped electrode 2
30 or the second rod-shaped electrode 231 is connected to a high-frequency power source 233 via a matching unit 232.
And the other is connected to ground which is a reference potential. As a result, plasma is generated in the plasma generation region 219 between the first rod-shaped electrode 230 and the second rod-shaped electrode 231.

The electrode protection tubes 218 and 220 have a structure in which the first rod-shaped electrode 230 and the second rod-shaped electrode 231 can be inserted into the buffer chamber 212 in a state of being isolated from the atmosphere of the buffer chamber 212. Here, if the inside of the electrode protection tubes 218 and 220 is the same atmosphere as the outside air (atmosphere), the first rod-shaped electrode 230 and the second rod-shaped electrode 231 inserted into the electrode protection tubes 218 and 220 are the heater 3. It will be oxidized by heating. Therefore, the electrode protection tube 218,
An inert gas purge mechanism is provided for filling or purging the interior of 220 with an inert gas such as nitrogen to prevent the oxidation of the first rod-shaped electrode 230 or the second rod-shaped electrode 231 by suppressing the oxygen concentration sufficiently low. It is done.

Furthermore, from the position of the gas supply hole 214 to the inner wall that has turned the inner circumference of the reaction tube 2 about 120 °,
A buffer chamber 216 is provided. The buffer chamber 216 is for supplying a processing gas different from the processing gas supplied from the buffer chamber 212 when supplying a plurality of types of gases one by one to the wafer 1 in film formation by the ALD method. . Similarly to the buffer chamber 212, the buffer chamber 216 has gas supply holes 215 that are gas supply holes for supplying gas at the same pitch at positions adjacent to the wafer, and the gas supply pipe 10 is connected to the lower portion. Gas supply hole 21
When the differential pressure between the buffer chamber 216 and the processing chamber 52 is small, the opening area of 5 may be the same opening area from the upstream side to the downstream side with the same opening pitch, but when the differential pressure is large, the upstream side It is preferable to increase the opening area toward the downstream side or to decrease the opening pitch.

A boat 115 on which a plurality of wafers 1 are placed in multiple stages at the same interval is provided in the center of the reaction tube 2 so that the boat 115 can enter and exit the reaction tube 2 by a boat elevator mechanism (not shown). It has become. Further, in order to improve the uniformity of processing, a boat rotation mechanism 112 which is a rotation means for rotating the boat 115 is provided. By rotating the boat rotation mechanism 112, the boat 115 held by the quartz cap 116 is removed. It is designed to rotate.

The control device 9 serving as a control means includes flow rate controllers 23, 33, 41, valves 34, 35, 36.
, 42, heater 3, exhaust pipe heater 20, TRIE supply pipe heater 22, ozone supply pipe heater 24, vacuum pump 8, boat rotation mechanism 112, boat lifting mechanism not shown in the figure, high frequency power supply 233, matching unit 232 Connected to the flow controller 23, 33, 4
1 flow rate adjustment, opening / closing operation of valves 34, 35, 36, 42, exhaust pipe heater 20, T
Adjusting the output of the RIES supply pipe heater 22 and the ozone supply pipe heater 24, starting / stopping the vacuum pump 8, adjusting the rotation speed of the boat rotation mechanism 112, raising / lowering operation control of the boat lifting mechanism, power supply control of the high frequency power supply 233, Impedance control by the matching unit 232 is performed.

Next, an example of process processing for a substrate such as a wafer performed in the embodiment of the present invention will be described. The substrate processing will be described using the processing furnace 101 of the first embodiment shown in FIG.

Examples of the present invention were performed by the ALD method. In the ALD method, under a certain film formation condition (temperature, time, etc.), two kinds (or more) of processing gases used for film formation are alternately supplied onto the substrate one by one, and one atomic layer In this method, the film is formed by adsorbing in units and utilizing surface reaction.
The film thickness is controlled by the number of processing gas supply cycles. For example, the film formation rate is 1 mm /
As a cycle, when a 20-mm film is formed, the treatment is performed 20 cycles. ALD
As a processing gas used in the processing, the first processing gas will be described as TRIE, and the second processing gas will be described using ozone as an example.

FIG. 5 is an example of a film forming recipe (film forming procedure) used at the time of forming the SiO ₂ film in the present invention. FIG. 6 illustrates the chemical reaction that occurs in each step shown in FIG. FIG.
This shows the molecular structure of TRIES and the bond energy between each atom. In FIG. 6, [C ₂ H ₅ (ethyl group)] in FIG. 9 is abbreviated as Et.

The film formation recipe shown in FIG. 5 includes STEP (1): TRIES supply step, STEP (2): inert gas purge step 1, STEP (3): ozone supply step, STEP (4): inert gas purge step 2. The steps are one cycle, and the procedure for controlling the film thickness by the number of cycles is shown.

STEP (1): TRIES supply step
In the TRIES supply / step, TRIES is supplied to the processing chamber 52 and TRIE is reacted to the substrate surface.
/ Adsorb.

In the present embodiment, with the valve 35 closed, the valve 34 is opened to perform TRIES in the processing chamber 5.
2 is supplied. When it is desired to increase the pressure in the processing chamber 52, the valve 36 may be opened and an inert gas such as argon (Ar) may be supplied into the processing chamber 52 to control the pressure.

As shown in FIG. 9, the smallest bond energy of TRIES is a Si—H bond. Therefore, in the TRIES supply step, this Si-H bond is broken, Si and O are bonded, and TREIS is adsorbed on the substrate.

STEP (2): Inert gas purge step 1
In the inert gas purge step 1, the unreacted gas in STEP (1) is purged with an inert gas and removed. For example, Ar can be used as the inert gas.

In the present embodiment, the unreacted gas of STEP (1) is exhausted from the processing chamber 52 with the valves 34 and 35 closed and the valve 37 opened to exhaust the atmosphere in the processing chamber 52. This time,
If the valve 37 is opened and the processing chamber 52 is evacuated by opening the valve 36 and supplying the inert gas into the processing chamber 52, the processing chamber 52 is also purged.

STEP (3): Ozone supply step In the ozone supply step, ozone is supplied to the processing chamber 52 and reacted with Si (OEt) ₃ reacting / adsorbing on the substrate surface to form a SiO ₂ film on the substrate 1. To do.

In the present embodiment, with the valve 34 closed, the valve 35 is opened and ozone is supplied to the processing chamber 52. If it is necessary to prevent the backflow of ozone, the valve 36 may be opened to allow the inert gas to flow.

As shown in FIG. 9, since the binding energy of the OC, CC, and CH bonds is relatively small, Et and O supplied from ozone react in the ozone supply step, and the components constituting the Et are CO _2.
, CH ₄ , H ₂ O, etc., leaving, and Si—O remains on the substrate.

STEP (4): Inert gas purge step 2
In the inert gas purge step 2, the unreacted gas in STEP (3) is purged with an inert gas and removed. For example, Ar can be used as the inert gas.

In the present embodiment, the unreacted gas of STEP (1) is exhausted from the processing chamber 52 with the valves 34 and 35 closed and the valve 37 opened to exhaust the atmosphere in the processing chamber 52. This time,
If the valve 37 is opened and the processing chamber 52 is evacuated by opening the valve 36 and supplying the inert gas into the processing chamber 52, the processing chamber 52 is also purged.

Steps (1) to (4) are repeated to form a SiO2 film on the substrate. The number of repetitions is arbitrarily changed according to the film forming temperature and the required film thickness. In addition, the inert gas purge steps 1 and 2 are caused by direct reaction between different processing gases such as TRIES and ozone.
In order to prevent the generation of by-products and cause particles, the process gas is purged with sufficient time to be completely discharged from the process chamber 52.

Although the above-described film forming recipe has been described by taking the processing furnace for processing the substrates shown in FIG. 1 one by one as an example, the film forming recipe can also be applied to one that simultaneously processes a plurality of substrates as shown in FIG.

Using the substrate processing apparatus and the substrate processing method as described above, an SiO ₂ film was formed on the substrate using the film formation recipe shown in FIG. 5, and the dependency between the film formation rate and temperature was examined.

FIG. 7 shows the temperature dependence of the film formation rate per cycle. TRIES supply step is 30 seconds,
The inert gas purge step 1 is 30 seconds, the ozone supply step (3) is 30 seconds, the inert gas purge step 2 is 4 seconds, and the total time is 94 seconds / cycle. As shown in FIG. 7, the film formation temperature is
It is 0.6 mm or more per cycle in the range of 350 ° C. to 450 ° C., and for example, the time required to form a film of 100 mm is 4 hours or less, and a film forming speed that can withstand practical use is secured.

FIG. 10 shows quantitative results of each element on the substrate surface obtained by ESCA (Electron Spectroscopy for Chemical Analysis). The content of the concerned C component is 2% or less, and it can be seen that the present invention is effective for the production of a SiO ₂ film having a low content of C despite the use of an organic material.

FIG. 8 is a concentration distribution in the depth direction of the C, H, and N components in the SiO ₂ film analyzed by SIMS (secondary ion mass spectrometry). The concentration distribution of both C and N is about 2 × 10 19 atoms / cm 3, and the content is low, similar to the result of ESCA in FIG.

In the present invention, the reason why the concentration of C in the film is low despite the high content of the C component in the raw material is that the ozone used as an oxidant is strong and sufficiently desorbs carbon from the film. Can be considered.

FIG. 11 is a comparison of film formation rates of ozone and oxygen. The film formation temperature is 450 ° C., the TRIES supply step is 40 ccm for 30 seconds, and the ozone (or oxygen) supply step is 30 seconds. It can be seen that the ozone generation rate is 5 times faster than oxygen alone. This is probably because ozone is more oxidizing than oxygen. When oxygen is used as the second reactant, it can be seen that oxygen is weak in oxidizing power and is preferably activated by plasma excitation and supplied to the processing chamber.

In the above-described film forming recipe, TRIE and ozone are used as the processing gas, but oxygen may be used instead of ozone. However, since oxygen has a weaker oxidizing power than ozone, it is preferably supplied into the processing chamber 52 in an activated state by plasma excitation. Therefore, when oxygen is used as the second processing gas, the processing furnace 201 shown in FIGS. 3 and 4 is used, oxygen is supplied from the oxygen supply pipe 213 to the buffer chamber 212, and the first rod electrode 230, It is preferable that the gas is supplied into the processing chamber 52 while being activated by the second rod-shaped electrode 231 or the like.

Further, N ₂ O may be used as the second processing gas.
However, since N ₂ O has a weak oxidizing power like oxygen, the processing furnace shown in FIGS. 3 and 4 is used to supply N ₂ O into the processing chamber 52 while being activated by plasma. preferable.

  The present invention also has the following features.

[1] carrying at least one substrate into the processing chamber;
Supplying SiH (OC ₂ H ₅ ) ₃ (triethoxysilane: hereinafter referred to as TRIES) and a substance containing oxygen atoms without containing hydrogen atoms to deposit a SiO 2 film on the substrate;
A step of unloading the substrate from the processing chamber;
A method for manufacturing a semiconductor device, comprising:

[2] carrying at least one substrate into the processing chamber;
Supplying a first processing gas containing TRIES into the processing chamber;
Supplying a second processing gas containing oxygen atoms without containing hydrogen atoms into the processing chamber;
Depositing a SiO ₂ film on the substrate by alternately repeating the first process gas supply step and the second process gas supply step a plurality of times;
A step of unloading the substrate from the processing chamber;
A method for manufacturing a semiconductor device, comprising:

[3] carrying at least one substrate into the processing chamber;
Supplying a first processing gas containing TRIES into the processing chamber;
Supplying a second processing gas containing oxygen atoms without containing hydrogen atoms into the processing chamber;
Supplying an inert gas into the processing chamber;
A first process gas supply step, an inert gas supply step, a second process gas supply step, an inert gas supply step,
The process of depositing the SiO ₂ film on the substrate by repeating a plurality of times in this order,
A step of unloading the substrate from the processing chamber;
A method for manufacturing a semiconductor device, comprising:

[4] The method for manufacturing a semiconductor device according to [1] to [3], wherein the processing chamber pressure in the deposition step is 1 Pa or more and 10,000 Pa or less.

[5] In the above [1] to [4], when supplying the first processing gas containing TRIE to the processing chamber, supply piping for supplying TRIES into the processing chamber and / or exhaust piping for exhausting the processing chamber A method for manufacturing a semiconductor device, characterized in that the temperature is 80 ° C. or higher and 170 ° C. or lower.

[6] The method for manufacturing a semiconductor device according to [1] to [5], wherein the temperature of the inner wall of the processing chamber is also 80 ° C. or higher and 170 ° C. or lower.

[7] The semiconductor device according to [1] to [6], wherein the temperature of the inner wall of the processing chamber is higher than the temperature of the supply piping for supplying TRIES into the processing chamber and the exhaust piping for exhausting the processing chamber. Manufacturing method.

[8] The method for manufacturing a semiconductor device according to [1] to [7], wherein the second processing gas is a substance selected from ozone (O ₃ ), O ₂ , and N ₂ O.

[9] In the above [1] to [8], the inert gas is helium (He) or neon (Ne).
, Argon (Ar), krypton (Kr), xenon (Xe), and nitrogen (N ₂ ).

[10] In the above [1] to [9], the at least one substrate is a plurality of substrates, and the film forming process is performed in a state where a plurality of substrates are supported in multiple stages with a gap in the processing chamber. Semiconductor device manufacturing process characterized by

[11] In the above [1] to [10], when O ₂ is selected as the second processing gas, O ₂
A method for manufacturing a semiconductor device, wherein plasma is excited to form an active species and is supplied to a processing chamber.

[12] a processing chamber for processing at least one substrate;
A heater provided in the processing chamber for heating the substrate;
A supply pipe for supplying a first processing gas containing TRIES in the processing chamber;
A supply pipe for supplying a second processing gas containing oxygen atoms without containing hydrogen atoms in the processing chamber;
A supply pipe for supplying an inert gas into the processing chamber;
An exhaust pipe for exhausting the processing chamber;
In the processing chamber, a first processing gas, an inert gas, a second processing gas, an inert gas,
A controller that controls to repeatedly supply a plurality of times in this order;
A method for manufacturing a semiconductor device, comprising:

Schematic (longitudinal sectional view) of the processing furnace according to Example 1 Schematic (longitudinal sectional view) of the processing furnace according to Example 2 Schematic (longitudinal sectional view) of the processing furnace according to Example 3 Schematic diagram (cross-sectional view) of a processing furnace according to Example 3 Deposition recipe according to an embodiment of the present invention Diagram illustrating film formation reaction at each processing step Diagram showing the relationship between deposition temperature and deposition rate The figure which shows the analysis result by SIMS Diagram showing the molecular structure of TRIES and each binding energy The figure which shows the result of ESCA Diagram showing the deposition rate when ozone and oxygen are used

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wafer 3 Heater 4 TRIE supplier 5 Ozone generator 7 Exhaust piping 8 Vacuum pump 9 Control device 52 Processing chamber 101 Processing furnace

Claims (2)

A processing chamber for receiving and processing substrates;
First gas supply means for supplying triethoxysilane as a processing gas first to the processing chamber;
A second gas supply means for supplying ozone as a second processing gas to the processing chamber;
A substrate processing apparatus comprising:
A substrate processing apparatus for processing a substrate by alternately supplying the first processing gas and the second processing gas into a processing chamber. A substrate carrying-in process for carrying the substrate into the processing chamber;
A first gas supply step of supplying triethoxysilane as a first processing gas to the processing chamber;
A first exhaust process for exhausting the first process gas from the process chamber; a second gas supply process for supplying ozone as the second process gas to the process chamber;
A semiconductor device manufacturing method comprising: a second exhaust process for exhausting a second process gas from the process chamber.

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