JP2005327804A - Semiconductor manufacturing equipment and method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an increase in manufacturing cost and decline in operation time as much as possible, and to manufacture semiconductor devices under stable processing conditions. <P>SOLUTION: Semiconductor manufacturing equipment comprises a reaction chamber 2 for performing plasma treatment, introductory pipe 18 for introducing gas for treatment into the reaction chamber, top electrode 10 installed above the reaction chamber, bottom electrode 12 which is installed opposite to the top electrode in the reaction chamber and whereon a substrate 100 to be treated is to be placed, high-frequency power source 16 which is electrically connected to the top electrode and/or the bottom electrode and applies high-frequency power between the top electrode and the bottom electrode to generate plasma of the gas for treatment, a vacuum pump 22 for evacuating the reaction chamber to make it to the prescribed pressure, and at least two kinds of inner walls 4 and 6 which are installed on the side in the reaction chamber, with at least one of these being movable up and down. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a semiconductor manufacturing apparatus and a semiconductor device manufacturing method for performing processing using plasma.

  As semiconductor devices have higher performance, higher integration, and miniaturization, particles that adhere to the semiconductor substrate during the manufacturing process have an increasing influence on the characteristics and production yield of the semiconductor device. Furthermore, in order to improve the productivity of semiconductor devices and promote efficiency, it is required to improve the stability of the processing conditions of the semiconductor manufacturing apparatus.

  As a generation source of particles, in addition to dust generation from a transport system of a semiconductor manufacturing apparatus, dust generation from a person, reaction products in a processing step using plasma are raised. Particles are often generated when the reaction product with a low vapor pressure adheres to the inner wall of the reaction chamber (chamber) and peels off, especially when processing with different processing conditions is performed in the same reaction chamber. The frequency of occurrence increases.

  In a semiconductor manufacturing apparatus that performs plasma processing such as dry etching or CVD (Chemical Vapor Deposition), it may be possible to dedicate a reaction chamber for each different processing condition in order to suppress the generation of particles. In this case, since the reaction chamber is dedicated, there is a problem that the number of semiconductor manufacturing apparatuses increases and the manufacturing cost increases.

  Therefore, in order to suppress an increase in manufacturing cost, it is necessary to take measures to suppress the generation of particles even when the semiconductor manufacturing apparatus is shared, that is, when processing with different processing conditions is performed in the same reaction chamber. The processing conditions largely depend on the state of the inner wall of the reaction chamber, and controlling the state of the inner wall of the reaction chamber is important for improving the stability of the processing conditions.

Conventionally, as a measure to suppress the generation of particles,
1) After the reaction chamber is opened to the atmosphere, wet reaction using chemicals or dry cleaning using plasma is performed to remove reaction products attached to the inner wall of the reaction chamber.
2) A removable protective film covering the inner wall of the reaction chamber is provided, and the reaction product adhering to the protective film is cleaned (for example, see Patent Document 1).
3) An exchangeable jacket is provided on the inner wall of the reaction chamber, and when the reaction product is deposited, the jacket is exchanged (for example, see Patent Document 2).
It is known.

However, when a plurality of treatments having different treatment conditions are performed, if the same reaction chamber is used, the deposits adhering to the inner wall of the reaction chamber naturally differ for each treatment condition. For this reason, every time processing is performed, the processing conditions themselves change, processing cannot be performed stably, and particles increase. In order to prevent an increase in particles, it is necessary to perform cleaning each time processing with different processing conditions is performed or to replace the above-described protective film and jacket. This causes a problem that the operating time of the semiconductor manufacturing apparatus is reduced.
Japanese Patent Publication No. 2720420 JP 2000-150487 A

  An object of the present invention is to provide a semiconductor manufacturing apparatus and a semiconductor device manufacturing method capable of manufacturing a semiconductor device under stable processing conditions while preventing an increase in manufacturing cost and a reduction in operating time as much as possible. To do.

  A semiconductor manufacturing apparatus according to a first aspect of the present invention includes a reaction chamber for performing plasma processing, an introduction pipe for introducing a processing gas into the reaction chamber, an upper electrode provided above the reaction chamber, and the upper portion A lower electrode provided in the reaction chamber so as to face the electrode and on which a substrate to be processed is placed; and at least one of the upper electrode and the lower electrode and electrically connected between the upper electrode and the lower electrode A high-frequency power source that applies high-frequency power to generate plasma of the processing gas, a vacuum pump that exhausts the reaction chamber to a predetermined pressure, and at least one of the top and bottom provided on the side of the reaction chamber And at least two types of movable inner walls.

  Further, in the method for manufacturing a semiconductor device according to the second aspect of the present invention, a processing gas is introduced into a reaction chamber, and high-frequency power is applied between an upper electrode and a lower electrode provided in the reaction chamber, and the processing gas is supplied. In which a plasma processing is performed on a substrate to be processed placed on the lower electrode, wherein at least one side portion of the reaction chamber has a plurality of inner walls that can move up and down. And performing two or more types of processing with different processing conditions on the substrate to be processed without opening the reaction chamber to the atmosphere, and moving an inner wall that can be moved up and down between the two or more types of processing. Thus, the inner wall of the side portion of the reaction chamber between the upper electrode and the lower electrode is changed.

  According to the present invention, an increase in manufacturing cost and a reduction in operating time can be prevented as much as possible, and a semiconductor device can be manufactured under stable processing conditions.

(First embodiment)
A semiconductor manufacturing apparatus according to a first embodiment of the present invention will be described with reference to FIGS. The semiconductor manufacturing apparatus 1 according to the present embodiment is a plasma processing apparatus, and a process for etching a SiO ₂ film formed on a substrate to be processed 100 using a mask made of a resist formed on the SiO ₂ film. And ashing the mask made of the resist. FIG. 1 is a cross-sectional view of the semiconductor manufacturing apparatus 1 according to the present embodiment when the SiO ₂ film is etched using a resist mask. FIG. 2 is a cross-sectional view of the semiconductor manufacturing apparatus 1 according to the present embodiment made of resist. It is sectional drawing in the case of performing an ashing process on a mask.

The semiconductor manufacturing apparatus 1 of the present embodiment includes a reaction chamber 2, and an inner wall 4 when etching the SiO ₂ film and an inner wall when ashing a mask made of resist are formed on the side surface of the reaction chamber 2. 6 is provided. The inner wall 6 can be moved up and down by a driving mechanism (not shown), and when etching the SiO ₂ film, as shown in FIG. 1, the inner wall 6 moves downward and is contained in a storage unit 8 provided below the reaction chamber 2. When the mask made of resist and made of resist is subjected to ashing, it moves upward and becomes the inner wall of the reaction chamber 2 as shown in FIG. Note that when the inner wall 6 is stored in the storage portion 8, the inner wall 4 serves as the inner wall of the reaction chamber 2.

  The reaction chamber 2 is provided with an upper electrode 10 also serving as an upper wall and a lower electrode 12 having an electrostatic chuck for fixing the substrate 100 to be processed. The lower electrode 12 is connected to a high frequency power supply 16 via a capacitor 14. Further, the electrostatic chuck has a function capable of holding the substrate to be processed 100 at an arbitrary temperature in the range of -30 ° C to 120 ° C.

In addition, the reaction chamber 2 is provided with an introduction pipe 18 into which an etching gas used for etching the SiO ₂ film and an ashing gas used for ashing a resist mask are introduced, and the etching gas and the ashing gas are discharged. A discharge pipe 20 is connected for the purpose. The etching gas and ashing gas are forcibly exhausted by the vacuum pump 22 through the exhaust pipe 20.

Next, the operation when the SiO ₂ film of the semiconductor manufacturing apparatus 1 according to the present embodiment is etched will be described.

First, a substrate to be processed 100 having a resist mask formed on a SiO ₂ film is prepared and fixed on the lower electrode 12 by an electrostatic chuck. At this time, the inner wall of the side portion of the reaction chamber 2 is in a state where the inner wall 6 is stored in the storage portion 8 and the inner wall 4 is exposed.

A C ₄ F ₈ / CO / Ar mixed gas as a SiO ₂ etching gas is introduced into the reaction chamber 2 through the introduction tube 18 at a flow rate of 16/300/380 sccm, respectively, and the substrate 100 to be processed is heated to 60 ° C. by an electrostatic chuck. In addition, after controlling the pressure in the reaction chamber 2 to 40 mTorr by the vacuum pump 22, 1700 W of high frequency power is applied between the upper and lower electrodes 10 and 12 by the high frequency power source 16 to generate plasma between the upper and lower electrodes 10 and 12, A SiO ₂ etching process is performed. At this time, the inner wall of the side portion of the reaction chamber 2 is in a state where the inner wall 6 is accommodated in the accommodating portion 8 and the inner wall 4 is exposed, so that the reaction product (fluorocarbon) generated by the SiO ₂ etching process is It accumulates on the inner wall 4 of the reaction chamber 2 and does not accumulate on the inner wall 6.

Next, the resist used as the SiO ₂ processing mask is stripped (ashing / removal). When continuous processing is performed using a conventional semiconductor manufacturing apparatus, reaction products during the SiO ₂ processing are deposited on the inner wall. As it is, peeling treatment is performed. For this reason, at the time of resist stripping treatment, there are problems such as etching of SiO _{2 and} peeling of products on the inner wall leading to generation of particles (dust).

In contrast, in this embodiment, following the etching of SiO _2, when the resist stripping, as shown in FIG. 2, the inner wall 6 of the reaction chamber 2 is moved upward, SiO ₂ treatment The resist peeling process is performed in a state where the inner wall 4 is isolated from the plasma. After introducing an O ₂ / Ar mixed gas as a resist ashing gas into the reaction chamber 2 at a flow rate of 300/100 sccm, the substrate to be processed 100 is controlled to 60 ° C. by an electrostatic chuck, and the pressure is controlled to 40 mTorr by a vacuum pump 22. Then, 800 W of high frequency power was applied between the upper and lower electrodes 10 and 12 to generate plasma, and a resist ashing process was performed. At this time, since the inner wall 4 to which SiO ₂ is adhered is not exposed to plasma, it is possible to prevent the generation of particles (dust) due to the deposit on the inner wall 4 being peeled off, and the semiconductor device under stable processing conditions. Can be manufactured.

As described above, according to the present embodiment, it is possible to stabilize the state of the inner wall by changing the inner wall of the reaction chamber according to the SiO ₂ etching processing condition and the resist ashing processing condition according to the processing condition. A semiconductor device can be manufactured under the processing conditions. As a result, it is possible to prevent a decrease in the manufacturing yield of the semiconductor device, and an increase in the manufacturing cost of the semiconductor device can be prevented. Further, it is not necessary to clean the inner wall of the reaction chamber for each processing condition. For this reason, compared with the case where the inner wall of the reaction chamber is cleaned for each processing condition, the time for stopping the semiconductor manufacturing apparatus is short, and the apparatus can be operated efficiently. In addition, a plurality of processes can be performed with one semiconductor manufacturing apparatus, and an increase in manufacturing cost can be prevented.

  In this embodiment, the processing conditions are switched for each wafer. However, the same result is obtained even when the processing is switched in units of one lot (for example, 24 wafers).

Further, in the present embodiment, the inner wall 6 for ashing processing is stored in the storage unit 8, but the storage unit 8 may be integrated with the reaction chamber 2 as shown in FIG. 3. In this case, when the ashing process is not performed, the inner wall 6 for the ashing process is preferably moved so as to be below the lower electrode 12 in order to prevent exposure to the plasma of the SiO ₂ etching gas.

(Second Embodiment)
Next, a semiconductor manufacturing apparatus according to a second embodiment of the present invention will be described. The semiconductor manufacturing apparatus according to the present embodiment is used for high-mix low-volume production.

There are a wide variety of semiconductor processes, and conventionally, processing is performed by a dedicated device for each process. However, as in the case of high-mix low-volume production, if a semiconductor manufacturing device is dedicated, the cost of the semiconductor manufacturing device and the manufacturing cost of the semiconductor device are more than necessary, and the efficiency deteriorates. Need to perform multiple processes. For example, in order to perform a plurality of processes (SiO ₂ etching → resist ashing) with one etching apparatus, cleaning of the reaction chamber (mostly removal of the fluorocarbon film with O ₂ ) is performed under the conditions for actually performing the process. (Many of them are state control by CF-based gas) seasoning is required, and mixed use of processes is being studied. However, in this case, it is difficult to avoid the problems of dust control and deterioration of parts (for example, inner walls). In addition, it is impossible to mix the processes of SiO ₂ processing → ashing → Al processing → ashing using the same reaction chamber because the components in the reaction chamber are different. This is because when SiO ₂ processing is performed, a component mainly composed of Al is used. When ashing is performed, a component mainly composed of SiO ₂ is used, and when performing Al processing, SiO ₂ is performed. Therefore, it is impossible to select a suitable part for each.

The semiconductor manufacturing apparatus of the present embodiment is the same as the semiconductor manufacturing apparatus shown in FIG. 1 in three types of inner walls, for example, a first inner wall made of Al for SiO ₂ processing, a second inner wall made of SiO ₂ for ashing, and Al processing. A third inner wall made of SiO ₂ is provided, and at least two of the three types of inner walls can be moved up and down. Then, a first internal wall made of the Al for SiO ₂ processing, ashing processing the second internal wall made of SiO _2, using a third inner wall of SiO ₂ to Al machining.

  Thus, by moving the inner wall up and down according to each processing condition, the inner wall state of the reaction chamber can be separated, and the inner wall state can be stabilized. Therefore, it is possible to stabilize the processing conditions and it is not necessary to clean the inner wall of the reaction chamber for each processing condition. For this reason, compared with the case where the inner wall of the reaction chamber is cleaned for each processing condition, the time for stopping the semiconductor manufacturing apparatus can be shortened, and the semiconductor manufacturing apparatus can be operated efficiently. In addition, since the processing conditions can be stabilized, the manufacturing yield of semiconductor devices can be increased and the manufacturing cost can be reduced.

  In addition, it is necessary to replace parts required for each process except the inner wall (for example, a ring provided so as to surround the substrate to be processed placed on the lower electrode) for each process. However, the time required to replace these parts is much shorter than the time required to clean the reaction chamber, so that the semiconductor manufacturing apparatus can be operated efficiently even if the above parts are replaced.

  Note that the processing conditions may be switched for each wafer, or the processing may be switched in units of one lot (24 sheets).

  In the above embodiment, the plasma processing apparatus used for the etching process has been described. However, a CVD (Chemical Vapor Deposition) apparatus using plasma may be used.

Sectional view during SiO ₂ etching process of a semiconductor manufacturing apparatus according to a first embodiment of the present invention. Sectional drawing at the time of the ashing process of the semiconductor manufacturing apparatus by 1st Embodiment of this invention. Sectional drawing which shows the structure of the semiconductor manufacturing apparatus by the modification of 1st Embodiment.

Explanation of symbols

1 semiconductor manufacturing apparatus 2 the reaction chamber 4 SiO ₂ etching process for the inner wall 6 ashing for the inner wall 10 the upper electrode (upper wall)
12 Lower electrode 16 High frequency power supply 18 Introduction pipe 22 Vacuum pump

Claims (5)

  A reaction chamber for performing plasma treatment; an introduction pipe for introducing a processing gas into the reaction chamber; an upper electrode provided above the reaction chamber; and a cover provided in the reaction chamber so as to face the upper electrode. A plasma of the processing gas by applying a high-frequency power between the lower electrode on which the processing substrate is placed and at least one of the upper electrode and the lower electrode and being electrically connected to the upper electrode and the lower electrode A high-frequency power source that generates a vacuum, a vacuum pump that exhausts the reaction chamber to a predetermined pressure, and at least two types of inner walls that are provided on the side of the reaction chamber and that can move up and down. The semiconductor manufacturing apparatus characterized by the above-mentioned.   The semiconductor manufacturing apparatus according to claim 1, wherein the plasma process is an etching process or a CVD process.   The semiconductor manufacturing apparatus according to claim 1, wherein the movable inner wall is movable below the lower electrode.   A substrate to be processed placed on the lower electrode by introducing a processing gas into the reaction chamber, applying high-frequency power between an upper electrode and a lower electrode provided in the reaction chamber to turn the processing gas into plasma A method of manufacturing a semiconductor device in which plasma processing is performed, wherein at least one side portion of the reaction chamber has a plurality of inner walls that can move up and down, and the processing conditions differ from each other for the substrate to be processed. More than one type of treatment is performed without opening the reaction chamber to the atmosphere, and an inner wall that can be moved up and down is moved between the two or more types of treatment, so that the side of the reaction chamber between the upper electrode and the lower electrode is moved. A method of manufacturing a semiconductor device, wherein an inner wall is changed.   5. The method of manufacturing a semiconductor device according to claim 4, wherein the at least two kinds of processes include an etching process and an ashing process.

Images