JP2001123271A - Method of precoating plasma enhanced cvd system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occurrence of foreign substance in a film deposition process in a plasma enhanced CVD system using microwave and radio frequency(RF) plasma and to attain a plasma enhanced CVD system having high working ratio. SOLUTION: After the completion of NF3 plasma cleaning, microwave is introduced into a reaction chamber 1 and RF is applied to an upper chamber 2 to precoat the internal wall surface of the reaction chamber 1 with an SiO2 film of desired thickness. Owing to the confinement of molecules adsorbed on the wall surface immediately after plasma cleaning and the smoothing of the wall surface, the increase of foreign substance due to peeled-off layer at film deposition and the occurrence of foreign substance by abnormal electric discharge at the internal wall surface of the reaction chamber 1 at film deposition can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma CVD (c
In particular, in a high-density plasma CVD apparatus provided with a cleaning function for forming a film using microwave plasma and RF plasma and removing a wall deposit in a reaction chamber, cleaning of the wall deposited film is completed. This is related to the reduction of foreign matter later.

[0002]

2. Description of the Related Art Foreign matter (particles) generated in a semiconductor manufacturing apparatus is a major factor that lowers the yield and the operating rate of the apparatus. Plasma CVD devices are used to grow thin films on silicon wafers and other substrates. In the process of growing a thin film on the surface of a substrate such as a wafer using this apparatus, the thin film also grows on the inner wall surface of the reaction chamber other than the substrate and on other wall surfaces. This thin film differs depending on the type of film (SiO2, Si3N4, poly-Si, etc.), but when it is deposited to a certain thickness (several to several tens of μm), cracks occur in the film due to the internal stress of the film itself and the wall surface More peel off. The degree of this peeling greatly varies depending on the wall shape, surface treatment, and material on which the film is deposited. When the peeled matter generated by such a phenomenon adheres to the wafer surface, it becomes a foreign substance, causing disconnection or short circuit of the semiconductor circuit, which is a major cause of manufacturing defects.

Therefore, before such a phenomenon occurs, the film deposited on the wall surface of the reaction chamber must be removed. Therefore, the plasma CVD apparatus needs a cleaning function as well as a film forming function. As a cleaning method, a method of activating a cleaning gas with plasma and removing a deposited film by a chemical reaction or a sputtering action, that is, a so-called plasma cleaning method is often used. While this cleaning can remove reaction by-products on the wall surface, there is a problem that foreign matter frequently occurs after cleaning due to wall surface damage due to cleaning.

For example, in a plasma CVD apparatus for forming an insulating oxide film (SiO 2), a reaction by-product deposited on a wall of a reaction chamber peels off and adheres to a wafer. In order to prevent this, the deposited reaction by-products are periodically removed by dry cleaning using NF3 gas or the like.
At this time, since the deposition distribution of the reaction by-product is different from the etching distribution of the deposited film by the cleaning, if the deposit on the wall of the reaction chamber is entirely removed, the wall itself is etched in a portion where the film is removed in the initial stage. Overetch occurs. As a result, the wall surface becomes rough, and a reaction product or gas is adsorbed by the cleaning on the wall surface. Therefore, in the film formation after the cleaning is completed, foreign substances such as film peeling are frequently generated. To suppress this, Japanese Patent Application Laid-Open
JP-A-188488 and JP-A-8-97157 disclose a so-called precoat in which a film is deposited on a wall surface of a reaction chamber after cleaning to seal foreign matter.

[0005]

As described above, in the plasma CVD apparatus for an insulating film, the wall surface of the reaction chamber is roughened by cleaning, and there are reaction products and gas adsorbed by cleaning on the wall surface. In film formation, foreign matter is generated due to film peeling or the like. In addition, since a large amount of electrons generated by the plasma are accumulated in the insulating film on the wall of the reaction chamber, a large potential difference between the conductive wall and the insulating film causes a large number of foreign substances due to dielectric breakdown of the deposited film. There's a problem.

In the pre-coating method disclosed in the above publication, pre-coating is performed simply to prevent dielectric breakdown for sealing off foreign matter, and there is a possibility that foreign matter is generated at the time of deposition of the pre-coat, thereby contaminating the semiconductor element.

The present invention has been made in order to avoid this problem, and an object of the present invention is to provide a high-throughput plasma having a high operating rate by a precoating method which does not generate foreign matter during film formation.
It is to provide a VD device.

[0008]

In order to solve the above-mentioned problems, according to the present invention, after cleaning is completed, pre-coating is performed on the wall surface of the reaction chamber with the microwave plasma generated by the microwaves introduced from the introduction window on the wall surface of the reaction chamber. Alternatively, after cleaning is completed, RF is applied to the wall surface of the reaction chamber and RF plasma is pre-coated on the wall surface of the reaction chamber.

Alternatively, after the cleaning is completed, RF is applied to the substrate electrode, and the wall surface of the reaction chamber is pre-coated with RF plasma.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A plasma CVD apparatus according to a first embodiment of the present invention will be described with reference to FIGS. 1, 3 and 4 are side sectional views showing the shape of the side section of the reaction chamber 1.

The reaction chamber 1 is formed by an upper chamber 2 and a lower chamber 3 made of an Al alloy (A5052).
And the lower chamber 3 are insulated from each other by an insulating material 6. The upper chamber 2 has a plurality of gas nozzles 4 made of alumina (Al ₂ O ₃ ) or the like for introducing O ₂ or NF ₃ gas.
There are provided several microwave introducing windows 5 (made of quartz or the like) for introducing waves. In this window, a waveguide 18 for guiding microwaves is provided.
Is connected. A microwave oscillator 19 (frequency 2.45 GHz) for generating a microwave and a power supply 21 are attached to the end of the microwave oscillator 19. In addition, R
Matching box 7 and RF so that F power can be applied
Power supply 8 (frequency 13.56 MHz) is connected.
In addition, an ECR (Electron Cyclotron Resonance) region is formed on the outer surface of the upper chamber 2 near the exit of the microwave introduction window 5 to increase electron density, promote generation of ions and radicals, and generate high density plasma. And a permanent magnet 2 for confining the plasma generated in the reaction chamber 1 by a cusp magnetic field.
A plurality of 0s are arranged.

A plurality of gas nozzles 9 for introducing gases such as SiH ₄ , Ar, and NF ₃ are provided in the lower chamber 3 in a circumferential direction, and a turbo molecular pump 10 is mounted on a lower part. At the end of the turbo molecular pump 10, a roughing vacuum pump 11 such as a positive displacement pump and a gas processing device 12 are connected. The lower chamber 3 is grounded. In the reaction chamber 1, a substrate electrode 15 in which an electrostatic suction device 14 for sucking a wafer 13 for film formation processing is installed is installed. A matching box 16 and an RF power supply 17 are connected to the substrate electrode 15 so that RF power can be applied. The wafer 13 is heated not only by the heat input from the plasma but also by the incidence of ions and the heat of reaction. Since the temperature of the wafer 13 has a great influence on the film quality, the film formation rate, etc., it is necessary to control the temperature of the wafer 13. This temperature control is performed by varying the pressure of the helium (He) gas flowing in the gap between the wafer 13 and the electrostatic chuck 14.

FIG. 2 is an explanatory diagram for explaining a process flow in this embodiment.

As shown in this figure, the process proceeds by repeating film forming processing → cleaning → precoat → film forming → cleaning a plurality of times. When film formation is repeated a plurality of times, a film of a reaction by-product is gradually deposited on the inner wall surface of the reaction chamber 1 and the surface of the substrate electrode 15. When this film exceeds a certain thickness, cracks are generated in the deposited film due to the internal stress of the film itself, and in the worst case, they are peeled off from the wall surface. The peeled deposited film adheres to the surface of the wafer 13 and causes a short circuit or disconnection of the semiconductor element wiring, resulting in a manufacturing defect and a reduction in production efficiency. Therefore, before the number of foreign substances exceeds the allowable value, cleaning for removing the deposited film in the reaction chamber 1 is performed, and subsequently, pre-coating for preventing the generation of foreign substances due to cleaning is performed. Hereinafter, each specific method will be described.

(1) Film Forming Method A film forming method will be described with reference to FIG.

First, a wafer 13 is introduced into a reaction chamber 1 whose pressure has been adjusted by a turbo molecular pump 10 and a roughing vacuum pump 11 via a transfer chamber (not shown).
5, the wafer 13 is attracted by electrostatic force by applying a voltage to the electrostatic attracting device 14. In this state, for example, oxygen gas is introduced from the gas nozzle 4 and Ar and SiH ₄ gases are introduced from the gas nozzle 9 into the reaction chamber 1 in desired amounts by using a mass flow controller. Further, the pressure in the reaction chamber 1 is adjusted from several millimeters to several tens Pa using the turbo molecular pump 10 and the roughing vacuum pump 11. In this way, when a μ wave of several hundreds to several Kw is introduced from the μ wave introduction window 5, a large number of electrons generated in the ECR region are converted into O ₂ ,
Ar and SiH ₄ are turned into plasma, and SiH ₃ , which is a decomposition product of SiH ₄ , and oxygen and the like are generated on the wafer 13.
React on the surface of the substrate 13 to deposit an SiO ₂ film on the wafer 13. At the same time, the RF power supply 17 is connected to the substrate electrode 15.
When RF power of several hundreds to several Kw is applied using the matching box 16 and a plasma sheath is formed between the surface of the wafer 13 and the plasma, and a bias voltage (−several tens to thousands of volts) is generated. Ions (especially Ar) generated by turning the introduced gas into plasma enter the surface of the wafer 13 by an electric field. Thus, the SiO ₂ film deposited on the surface of the wafer 13 is sputtered with Ar ions. By doing so, the stepped portion such as the Al wiring
An O ₂ film can be formed without voids (voids). After depositing a desired film thickness, the gas introduction, the application of microwaves, and the application of RF are stopped, the applied voltage of the electrostatic chuck is cut off, and the wafer 13 is carried out of the reaction chamber 1.

(2) Cleaning Method A cleaning method will be described with reference to FIG.

First, the surface of the electrostatic adsorption device 14 is protected from plasma in the reaction chamber 1 whose pressure has been adjusted by the turbo-molecular pump 10 and the roughing vacuum pump 11 via the transfer chamber (not shown). A cover wafer 22 made of alumina or the like is introduced and placed on the substrate electrode 15. In this way, for example, a desired amount of NF ₃ gas is introduced into the reaction chamber 1 from the gas nozzle 4 using a mass flow controller. Then, the pressure in the reaction chamber 1 is adjusted from several to several thousand Pa using the turbo molecular pump 10 and the roughing vacuum pump 11, and several hundred to several hundred using the RF power source 8 and the matching box 7 in the upper chamber 2. By applying RF power of Kw, NF ₃ plasma is generated in the reaction chamber 1. NF ₃
F radicals and F ions generated by the decomposition of gas are converted to SiO ₂
The deposited film is cleaned (etched) by reacting with the Si of the film and being discharged as a gas such as SiF ₄ . At this time, the RF power supply applied to the substrate electrode 15 and the power supply 21 of the microwave oscillator 19 for generating the microwave are shut off.

The reaction by-products thus deposited are removed. At this time, since the deposition distribution of the reaction by-product is different from the etching distribution of the deposited film by the cleaning, if the deposit on the wall of the reaction chamber is entirely removed, the wall itself is etched in a portion where the film is removed in the initial stage. Overetch occurs. Therefore, in the film formation immediately after the completion of the cleaning, (1) the inner wall surface of the reaction chamber 1 is rough, and reaction products and gas adsorption by the cleaning remain on the inner wall surface.
Foreign substances frequently occur due to film peeling or the like. (2) Also, immediately after cleaning, since the conductive wall surface is exposed, when a large amount of electrons generated by the plasma are accumulated in the insulating film on the inner wall surface of the reaction chamber 1, the conductive wall surface and the insulating film may be separated. The dielectric breakdown of the deposited film occurs due to the potential difference therebetween, and foreign matter frequently occurs. In order to prevent these things, it is necessary to precoat the inner wall surface of the reaction chamber 1 immediately after cleaning.

(3) Precoating Method The precoating method will be described with reference to FIG. First,
The wafer 13 is introduced into the reaction chamber 1 whose pressure has been adjusted by the turbo molecular pump 10 and the roughing vacuum pump 11 via a transfer chamber (not shown), and is placed on the substrate electrode 15 and electrostatically attracted. A voltage is applied to the device 14 to attract the wafer 13 by electrostatic force. In this state, for example, oxygen gas from the gas nozzle 4 and Ar and SiH4 gas from the gas nozzle 9 are introduced into the reaction chamber 1 in desired amounts by using a mass flow controller, and the turbo molecular pump 10 and the roughing vacuum pump 1 are introduced.
1 to adjust the pressure in the reaction chamber 1 from several millimeters to several tens Pa. Thereafter, the power supply 21 is turned on, and several hundreds to several Kw of μ-waves are introduced from the μ-wave introduction window 5, so that a large number of electrons generated in the ECR region turn O ₂ , Ar, and SiH ₄ into plasma. Oxygen or the like reacts with SiH ₃ , which is a decomposition product of SiH ₄ generated by plasma, to deposit an SiO ₂ film on the inner wall surface of the reaction chamber 1. After depositing a film having a film thickness of several tens to several thousands nm so as not to cause a dielectric breakdown of the deposited film due to accumulation of electron wall surface during film formation, after introducing gas and stopping the power supply 21 for applying microwaves, The voltage applied to the electrostatic chuck is cut off, and the wafer 13 is carried out of the reaction chamber 1. The RF power supply 8 for the matching box and the RF power supply 17 for the matching box 17 are off.

By performing the above process, the inner wall surface of the reaction chamber 1 generated by the cleaning can be roughened, reaction by-products and gas adsorbed molecules can be contained, and the occurrence of foreign substances due to film peeling can be prevented. Further, a film having a sufficient pressure resistance can be deposited on the conductive wall surface exposed by the cleaning. Therefore, even if a large amount of electrons generated by the plasma are accumulated in the insulating film on the inner wall surface of the reaction chamber 1,
Since no dielectric breakdown occurs due to a potential difference between the conductive wall surface and the insulating film, no foreign matter is generated. As described above, according to the present embodiment, it is possible to realize a plasma CVD apparatus with a small amount of foreign substances and a high operation rate (throughput).

Hereinafter, various embodiments of the precoating method of the present invention will be described. The processes up to the precoat and the processes up to the electrostatic attraction of the wafer 13 at the time of the precoat are the same as those of the first embodiment, the description up to that point is omitted, and in the following description, the process after the electrostatic attraction of the wafer 13 is performed. The above steps are performed.

The pre-coating method for the plasma CVD apparatus according to the second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
Gas and Ar gas and SiH ₄ gas are introduced into the reaction chamber 1 from the gas nozzle 9 by using a mass flow controller, and a turbo molecular pump 10 and a roughing vacuum pump 11 are introduced.
Is used to adjust the pressure in the reaction chamber 1 to several millimeters to several tens Pa. At the same time, by turning on the RF power source 8 in the upper chamber 2 and applying RF power of several hundred to several Kw using the matching box 7, O ₂ , Ar, and SiH ₄ are turned into plasma. Thereby, SiH ₃ , which is a decomposition product of the generated SiH ₄ , reacts with oxygen and the like, and SiO _{2 is formed on the} inner wall surface of the reaction chamber 1.
Deposit the film. In order to prevent dielectric breakdown of the deposited film due to accumulation of electrons on the wall surface during film formation, the film thickness is several tens to several thousand n.
After depositing a film of m, gas introduction and RF application are stopped, the applied voltage of the electrostatic chuck is cut off, and the wafer 13 is carried out of the reaction chamber 1. Thus, as in the first embodiment, it is possible to realize a plasma CVD apparatus with little foreign matter generation and a high operation rate (throughput).

Next, a method of precoating a plasma CVD apparatus according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
From the gas nozzle 9 and Ar gas and SiH ₄ gas from the gas nozzle 9 are introduced into the reaction chamber 1 in a desired amount using a mass flow controller, and are reacted to several millimeters to several tens Pa using a turbo molecular pump 10 and a roughing vacuum pump 11. Adjust the pressure in the chamber 1. At the same time, by turning on the RF power supply 17 to the substrate electrode 15 and applying RF power of several hundred to several Kw using the matching box 16, O ₂ , Ar, and SiH ₄ are turned into plasma. Thereby, SiH ₃ which is a decomposition product of the generated SiH ₄ reacts with oxygen and the like, and S
An iO ₂ film is deposited. After depositing a film having a thickness of several tens to several thousands nm, the gas is introduced and the RF power is turned off so that the dielectric breakdown of the deposited film due to the accumulation of electrons on the wall surface does not occur during the film formation. Thereafter, the voltage applied to the electrostatic chuck is cut off, and the wafer 13 is carried out of the reaction chamber 1. This allows
As in the first embodiment, it is possible to realize a plasma CVD apparatus having a low operating rate (throughput) with less generation of foreign matter.

Next, a method of precoating a plasma CVD apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
Gas and Ar gas and SiO ₄ gas are introduced from the gas nozzle 9 into the reaction chamber 1 in a desired amount by using a mass flow controller, and a turbo molecular pump 10 and a roughing vacuum pump 11 are introduced.
And the pressure in the reaction chamber 1 is adjusted from several millimeters to several tens Pa by using the .mu.-wave of several hundreds to several Kw from the .mu.-wave introduction window 5, and the RF power source 8 and the matching box 7 are used for the upper chamber 2. By applying RF power of several hundred to several Kw, O ₂ , Ar, and SiH ₄ are turned into plasma. As a result, SiH ₃ , which is a decomposition product of the generated SiH ₄ , reacts with oxygen or the like, thereby depositing an SiO ₂ film on the inner wall surface of the reaction chamber 1. After depositing a film having a thickness of several tens to several thousands nm so as not to cause dielectric breakdown of the deposited film due to wall accumulation of electrons during film formation, and after stopping gas introduction, introduction of microwaves, and RF application. Then, the applied voltage of the electrostatic suction device is turned off, and the device is carried out of the reaction chamber 1. Thus, as in the first embodiment, it is possible to realize a plasma CVD apparatus with little foreign matter generation and a high operation rate (throughput).

Next, a method of precoating a plasma CVD apparatus according to a fifth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
Gas and Ar gas and SiH ₄ gas are introduced into the reaction chamber 1 from the gas nozzle 9 by using a mass flow controller, and a turbo molecular pump 10 and a roughing vacuum pump 11 are introduced.
Is used to adjust the pressure in the reaction chamber 1 to several millimeters to several tens Pa. Then, several hundreds to several Kw of μ-waves are applied from the μ-wave introduction window 5 to the substrate electrode 15 by using an RF power supply 17 and a matching box 16 to apply RF power of several hundreds to several Kw, so that O ₂ , Ar and SiH ₄ are turned into plasma. By reacting the generated SiH ₃ , which is a decomposition product of SiH ₄ , with oxygen and the like, an SiO ₂ film is deposited on the inner wall surface of the reaction chamber 1. After depositing a film having a thickness of several tens to several thousands nm so as not to cause dielectric breakdown of the deposited film due to wall accumulation of electrons during film formation, and after stopping gas introduction, introduction of microwaves, and RF application. Then, the applied voltage of the electrostatic suction device is turned off, and the device is carried out of the reaction chamber 1. As a result, as in the first embodiment, it is possible to realize a plasma CVD apparatus with little generation of foreign matter and a high operation rate (throughput).

Next, a method of precoating a plasma CVD apparatus according to a sixth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
Gas and Ar gas and SiH ₄ gas are introduced into the reaction chamber 1 from the gas nozzle 9 by using a mass flow controller, and a turbo molecular pump 10 and a roughing vacuum pump 11 are introduced.
, The pressure in the reaction chamber 1 is adjusted from several millimeters to several tens Pa, and RF power of several hundreds to several Kw is applied to the upper chamber 2 using the RF power source 8 and the matching box 7,
Further, by applying RF power of several hundreds to several kW using the RF power source 17 and the matching box 16 to the substrate electrode 15, O ₂ , Ar, and SiH ₄ are turned into plasma, and the generated SiH ₄ is decomposed. By reacting the substance SiH ₃ with oxygen or the like, an SiO ₂ film is deposited on the inner wall surface of the reaction chamber 1. After depositing a film having a thickness of several tens to several thousands nm so as not to cause dielectric breakdown of the deposited film due to wall accumulation of electrons during film formation, and after stopping gas introduction, introduction of microwaves, and RF application. Then, the applied voltage of the electrostatic suction device is turned off, and the device is carried out of the reaction chamber 1. Thus, as in the first embodiment, it is possible to realize a plasma CVD apparatus with little foreign matter generation and a high operation rate (throughput).

Next, a method of precoating a plasma CVD apparatus according to a seventh embodiment of the present invention will be described with reference to FIG.
FIG. 10 is a side sectional view showing the shape of the side section of the reaction chamber 1.

In this embodiment, for example, the gas nozzle 4
Gas and Ar gas and SiH ₄ gas are introduced into the reaction chamber 1 from the gas nozzle 9 by using a mass flow controller, and a turbo molecular pump 10 and a roughing vacuum pump 11 are introduced.
Is used to adjust the pressure in the reaction chamber 1 to several millimeters to several tens Pa. Then, several hundreds to several Kw of μ-waves are applied from the μ-wave introduction window 5 to the upper chamber 2 with RF power of several hundreds to several Kw using the RF power supply 8 and the matching box 7. Further, RF power of several hundreds to several Kw is applied to the substrate electrode 15 using the RF power supply 17 and the matching box 16.
Thereby, O ₂ , AR, and SiH ₄ are turned into plasma. Thus by SiH ₃ and oxygen or the like as a decomposition product of SiH ₄ produced is reacted, the SiO ₂ film is deposited in the reaction chamber 1 in the wall. After depositing a film having a thickness of several tens to several thousands nm so as not to cause dielectric breakdown of the deposited film due to wall accumulation of electrons during film formation, and after stopping gas introduction, introduction of microwaves, and RF application. Then, the applied voltage of the electrostatic adsorption device is turned off, and the reaction chamber 1 is turned off.
Take it out. Thus, as in the first embodiment, the plasma C having a high operation rate (throughput) with little generation of foreign matter is used.
A VD device can be realized.

The precoating method according to the eighth embodiment of the present invention will be described with reference to FIG. FIG. 11 is an explanatory diagram of the precoating method. In this embodiment, pre-coating is performed in two stages. As the first stage, the same precoat as in the first embodiment is performed, and then the same precoat as in the fourth embodiment is performed. Thus, as in the first embodiment, a plasma CVD apparatus with little foreign matter generation and a high operation rate (throughput) can be realized.

A precoating method according to a ninth embodiment of the present invention will be described with reference to FIG. FIG. 12 is an explanatory diagram of the precoating method. As in the eighth embodiment, pre-coating is performed in two stages. As the first stage, the same precoat as in the first embodiment is performed, and then the same precoat as in the fifth embodiment is performed. Thus, as in the first embodiment, the plasma CV having a low operating rate (throughput) with less generation of foreign matter is used.
D device can be realized.

The precoating method according to the tenth embodiment of the present invention will be described with reference to FIG. FIG. 13 is an explanatory diagram of the precoating method. As in the eighth embodiment, pre-coating is performed in two stages. As the first stage, the same precoat as in the first embodiment is performed, and then the same precoat as in the sixth embodiment is performed. Thus, as in the first embodiment, it is possible to realize a plasma CVD apparatus with little foreign matter generation and a high operation rate (throughput).

In addition, a pre-coating method in which Embodiments 1 to 6 are appropriately combined is also possible, and the same effect can be expected.

The semiconductor device to which the above-described embodiment can be applied includes a polysilicon film of a gate electrode wiring, a phosphorus-doped polysilicon film, an oxide film or a phosphorus glass film for element isolation and interlayer insulation, a capacitor, and the like. A semiconductor element provided with at least one film among Si ₃ N ₄ films for insulation may be mentioned.

[0040]

According to the present invention, in film formation immediately after plasma cleaning, foreign matter increases due to film peeling due to confinement of wall surface adsorbed molecules and smoothing of the wall surface, and dielectric breakdown of the deposited film on the inner wall surface of the reaction chamber 1. Therefore, there is an effect that a plasma CVD apparatus having a high operation rate (throughput) can be realized.

[Brief description of the drawings]

FIG. 1 is a partial side sectional view showing a configuration of a reaction chamber of a plasma CVD apparatus according to a first embodiment.

FIG. 2 is an explanatory diagram of a process flow of the first embodiment.

FIG. 3 is a partial sectional side view illustrating a configuration of a reaction chamber during cleaning according to the first embodiment.

FIG. 4 is a partial side sectional view showing a configuration of a reaction chamber at the time of precoating of the first embodiment.

FIG. 5 is a partial side sectional view showing a configuration of a reaction chamber at the time of precoating of a second embodiment.

FIG. 6 is a partial sectional side view illustrating a configuration of a reaction chamber at the time of precoating according to a third embodiment.

FIG. 7 is a partial side sectional view showing a configuration of a reaction chamber at the time of precoating of a fourth embodiment.

FIG. 8 is a partial side sectional view showing a configuration of a reaction chamber at the time of precoating according to a fifth embodiment.

FIG. 9 is a partial sectional side view showing a configuration of a reaction chamber at the time of precoating according to a sixth embodiment.

FIG. 10 is a partial side sectional view showing a configuration of a reaction chamber at the time of precoating according to a seventh embodiment.

FIG. 11 is an explanatory diagram of a precoating method according to an eighth embodiment.

FIG. 12 is an explanatory diagram of a precoating method according to a ninth embodiment.

FIG. 13 is an explanatory diagram of a precoating method according to a tenth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reaction chamber, 2 ... Upper chamber, 3 ... Lower chamber, 4 ... Gas nozzle, 5 ... Microwave introduction window, 6 ... Insulating material, 7 ... Matching box, 8 ... RF power supply, 9 ... Gas nozzle, 10 ... Turbo molecular pump , 11: roughing vacuum pump, 12: gas processing device, 13: wafer, 14: electrostatic suction device, 15: substrate electrode, 16: matching box, 17: RF power supply,
18 ... waveguide, 19 ... microwave oscillator, 20 ... permanent magnet, 2
1 ... power supply, 22 ... cover wafer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masayuki Hachiya 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside Kokubu Works, Hitachi, Ltd. (72) Katsumi Oyama 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 F-term in Hitachi Kokubu Office (reference) 4K030 AA06 AA14 BA44 DA06 EA04 FA02 FA03 KA14 KA30 LA11 5F045 AA10 AB03 AB32 AB33 AC01 AC02 AC11 AC16 BB14 DP02 EB05 EB06 EB11 EH17

Claims (4)

[Claims] (1) Micro (μ) wave plasma and RF (radio frequency) plasma are generated in a reaction chamber, and a thin film is formed on a wafer or the like installed on a substrate electrode, and the thin film is deposited on a wall surface of the reaction chamber by film formation. A pre-coating method for a plasma CVD apparatus having a plasma cleaning function for removing deposits, characterized in that after cleaning is completed, pre-coating is performed on a wall of the reaction chamber with a microwave plasma generated by a microwave introduced from an introduction window on a wall of the reaction chamber. Pre-coating method for a plasma CVD apparatus. 2. A microwave plasma and RF in a reaction chamber.
(radio frequency) Pre-coating of a plasma CVD device equipped with a plasma cleaning function that generates plasma, forms a thin film on a wafer or the like placed on a substrate electrode, and removes deposits deposited on the walls of the reaction chamber by film formation. In the method, RF is applied to the reaction chamber wall after cleaning is completed, and RF is applied.
A pre-coating method for a plasma CVD apparatus, comprising pre-coating a wall of a reaction chamber with plasma. 3. A microwave plasma and RF in a reaction chamber.
(radio frequency) Pre-coating of a plasma CVD device equipped with a plasma cleaning function that generates plasma, forms a thin film on a wafer or the like placed on a substrate electrode, and removes deposits deposited on the walls of the reaction chamber by film formation. A precoating method for a plasma CVD apparatus, comprising applying RF to a substrate electrode after cleaning and precoating a wall of a reaction chamber with RF plasma. 4. A semiconductor device comprising at least one of a polysilicon film for a gate electrode wiring, a phosphorus-doped polysilicon film, an oxide film and a phosphorus glass film for element isolation and interlayer insulation, and a Si3N4 film for capacitor insulation. In semiconductor devices,
4. A semiconductor device, wherein at least one of the films is formed by using the plasma CVD apparatus according to claim 1.