JP2004063649A - Substrate treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment apparatus by which productivity is improved and costs are reduced by equalizing the etching speed distribution in the case of cleaning. <P>SOLUTION: A seating 4, a wafer support plate 2, a heat leveling plate 3 and a wafer support plate 2 are provided in this order from a lower side. A spacer 6 is provided in respective spaces between these members. A support 5 is fitted to the seating 4 and extends a hole 21 at the wafer support plate 2, a hole 31 at the heat leveling plate 3, and a hole 61 at the spacer 6. The spacer 6 is provided with a notch 62. Since etching gas or an etching liquid is easily infiltrated to the space between the spacer 6 and the support 5 via the notch 62 of the spacer 6, this part is prevented from remaining un-etched, thereby equalizing the etching speed distribution. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate processing apparatus, and more particularly to a thermal CVD for forming a thin film such as a metal film, a metal silicide film, an oxide film, a nitride film, or a silicon film doped with impurities or the like on a semiconductor wafer substrate surface in a semiconductor manufacturing process. Equipment, a plasma CVD apparatus, an epitaxial growth apparatus for growing a single crystal layer on a semiconductor wafer substrate, and a semiconductor wafer processing apparatus such as a dry etching apparatus for etching a thin film into a predetermined pattern. Further, the present invention relates to a semiconductor wafer processing apparatus suitable for a case where reaction by-products can be deposited on a wafer substrate holding section.
[0002]
[Prior art]
In the manufacture of semiconductor devices, various vacuum processing apparatuses such as CVD apparatuses and etching apparatuses are used as processing apparatuses for forming circuits on wafers. In the process of processing a wafer by these devices, minute dust due to reaction by-products and the like generated in the processing chamber adheres to the wafer surface. This is the main cause of the yield in the manufacturing process of the semiconductor element and the reduction of the operation rate of the device. Therefore, in order to reduce dust adhering to the wafer surface, reaction by-products deposited on the wall surface of the processing chamber by film formation are appropriately cleaned (removed).
[0003]
As a known technique relating to such film formation and cleaning, for example, there is a technique described in Japanese Patent Application Laid-Open No. 7-94419. In this known technique, a flat quartz-made reaction tube or the like is provided in a heating space formed by two parallel flat plate heaters, and a portion substantially disposed in the reaction tube and substantially corresponding to a wafer region is cut out. A semiconductor wafer is placed on a wafer support plate and exhausted while supplying gas into the processing chamber while heating, thereby forming a thin film (or epitaxial growth) on the wafer surface. When this film forming process is repeated and reaction by-products accumulate on the wall surface of the reaction tube, and the amount of the reaction by-product exceeds a limit value (thickness) and the sediment comes off, the gas reaction is appropriately performed. A cleaning is performed and deposits are removed by etching.
[0004]
As a wafer support used in the above-mentioned known semiconductor processing apparatus, for example, a wafer support 200 as shown in FIG. 1 can be mentioned. The wafer support 200 is set in the processing chamber of the semiconductor processing apparatus, and includes a pedestal 4 (see FIG. 2), a wafer support plate 2 (see FIG. 3), a heat equalizing plate 3 (see FIG. 4) if necessary, and a wafer support. It is composed of an inter-plate spacer 6 (see FIG. 5). As shown in FIG. 2, the pedestal 4 is provided with at least three or more columns 5, and the wafer support plate 2 is provided with holes 21 corresponding to the pedestal columns 5 as shown in FIG. The inner diameter of the spacer 6 is larger than the outer diameter of the column 5 and the diameter of the hole 21 of the wafer support plate 2, and determines the height of the wafer support plate 2 via the spacer 6. When there are two or more wafer support plates 2 or heat equalizing plates 3 or the like, the height and spacing of each can be determined by the spacer 6. In general, the contact between the wafer support plate 2 or the soaking plate 3 and the spacer 6 is flat and flat.
[0005]
[Problems to be solved by the invention]
When the film forming process is repeatedly performed in the conventional semiconductor wafer processing apparatus using the above-described wafer support 200, a reaction by-product is deposited on the inner wall of the reaction tube and the wafer support 200. Further, as shown in FIG. 7, when attention is paid to the spacer 6, the reaction by-product 63 is deposited also in an extremely narrow space between the pedestal support 5 and the spacer inner wall 64. When these reaction by-products 63 are cleaned with, for example, a reaction gas, the etching gas does not easily flow into the space between the pedestal support 5 and the inner wall 64 of the spacer, and the etching rate is extremely slow as compared with most other parts. Therefore, the etching residue easily occurs, and when the wafer film forming process is restarted, the above-mentioned etching remaining portion becomes a particle generation source. In addition, it takes a long etching time to completely remove the deposit without remaining the etching, the operation rate of the apparatus is reduced, over-etching of other parts occurs, and damage to quartz, which is a material of the wafer support 200, is reduced. As a result, the generation of particles and the quartz part replacement cycle are shortened, and the operating cost is increased.
[0006]
The above-described problem is the same when wet cleaning is performed, and a portion sandwiched between the column 5 and the inner wall 64 of the spacer has an etching residue. As a countermeasure method, there is a method of disassembling the quartz member constituting the wafer support 200 and performing wet cleaning. However, in a state where the reaction by-product 63 is deposited, the quartz member often adheres to the quartz member, and forcibly disassemble. In this case, quartz is damaged, which is inefficient.
[0007]
A main object of the present invention is to provide a substrate processing apparatus capable of realizing an improvement in productivity and a reduction in cost by achieving a uniform etching rate distribution during cleaning.
[0008]
[Means for Solving the Problems]
According to the present invention, there is provided a substrate processing apparatus including a processing chamber for processing a substrate, and a substrate support for supporting the substrate in the processing chamber, wherein the substrate support includes a plurality of constituent members, A substrate processing apparatus is provided in which at least one of the members is provided with a guide for assisting the cleaning medium to go around at least a part of the space between the plurality of members.
[0009]
The plurality of constituent members of the substrate support preferably include a plurality of substrate support plates that support the substrate, and a spacer that is provided between the plurality of substrate support plates and separates the substrate support plates from each other. The guide for assisting the wraparound is provided on at least one of the substrate support plate and the spacer at a contact portion between the substrate support plate and the spacer.
[0010]
The plurality of constituent members of the substrate support preferably include a pedestal, a substrate support plate for supporting the substrate, and a spacer provided between the pedestal and the substrate support plate for separating the pedestal and the substrate support plate. In this case, preferably, the guide for assisting the wraparound of the cleaning medium is provided on at least one of the substrate support plate and the spacer at a contact portion between the substrate support plate and the spacer. It is also preferable that the guide for assisting the cleaning medium to wrap around is provided on at least one of the pedestal and the spacer at the contact portion between the pedestal and the spacer. More preferably, a guide for assisting the wraparound of the cleaning medium is provided on at least one of the substrate support plate and the spacer at a contact portion between the substrate support plate and the spacer, and at a contact portion between the pedestal and the spacer, at least one of the pedestal and the spacer. Also provided on one side.
[0011]
Further, the plurality of constituent members of the substrate support are preferably provided with a substrate supporting plate for supporting the substrate, a soaking plate, and provided between the soaking plate and the substrate supporting plate to separate the soaking plate and the substrate supporting plate. And a spacer to be used. In this case, preferably, the guide for assisting the wraparound of the cleaning medium is provided on at least one of the substrate support plate and the spacer at a contact portion between the substrate support plate and the spacer. It is also preferable that the guide for assisting the cleaning medium to wrap around is provided on at least one of the heat equalizing plate and the spacer at the contact portion between the heat equalizing plate and the spacer. More preferably, a guide for assisting the wraparound of the cleaning medium is provided on at least one of the substrate support plate and the spacer at a contact portion between the substrate support plate and the spacer. And at least one of the spacers.
[0012]
Preferably, the plurality of constituent members of the substrate support further include a support. It is preferable to provide three or more columns. Also, preferably, holes are made in the spacer, the substrate support plate, and the heat equalizing plate (when included in a plurality of components of the substrate support), and the columns are passed through these holes.
[0013]
In each of the above cases, preferably, a guide for assisting the wraparound of the cleaning medium is provided on the spacer.
[0014]
Preferably, a plurality of guides (at least two) are provided to assist the cleaning medium to wrap around.
[0015]
The cleaning medium is preferably a cleaning gas (etching gas).
Further, the cleaning medium is preferably an etchant.
[0016]
Further, according to the present invention, there is provided a substrate processing method for processing a substrate using the above substrate processing apparatus.
[0017]
Further, according to the present invention, there is provided a method of manufacturing a semiconductor device including a step of processing a substrate using the substrate processing apparatus.
[0018]
Note that a semiconductor wafer is preferably used as the substrate.
[0019]
According to the present invention,
A processing chamber for processing a semiconductor wafer, heating means capable of heating the processing chamber, a pedestal having at least three or more columns, one or more wafer support plates, one or more heat equalizing plates, And a wafer support configured with a spacer, wherein the distance between the wafer support plate, the soaking plate, the distance between the wafer support plate and the soaking plate can be determined by the spacer dimensions described above. A semiconductor wafer processing apparatus characterized by having a gap at a contact portion between a wafer support plate and a spacer for assisting the flow of an etchant such as a cleaning gas.
Preferably, quartz is used for the wafer support material.
[0020]
Further, according to the present invention, using the above-described semiconductor wafer processing apparatus, reaction by-products deposited on the inner wall of the processing chamber and the surface of the wafer support are attached by introducing an etching gas such as CIF ₃ into the processing chamber. There is provided a method for cleaning a semiconductor wafer processing apparatus, comprising removing a deposit.
[0021]
Further, according to the present invention, by using the semiconductor wafer processing apparatus, the reaction by-product deposited on the wafer support surface is not decomposed into an etching solution such as a hydrofluoric acid or a hydrofluoric nitric acid solution without decomposing the wafer support. A method for cleaning a semiconductor processing apparatus, wherein a deposited substance is removed by immersion is provided.
[0022]
According to such a semiconductor wafer processing apparatus and a method for cleaning a semiconductor processing apparatus, the reaction by-products adhering to the pedestal support and the inner wall surface of the spacer are apt to flow around the etchant, and the difference in etching rate from most of the other by-products is reduced. As a result, when performing the reactive gas cleaning, the etching time can be shortened, and damage to the quartz member due to over-etching can be reduced. Further, even when performing wet cleaning, the difference in etching rate between the pedestal support, the inner surface of the spacer, and most of the other portions is reduced, and overetching is reduced, and the entire surface of the holding portion can be cleaned. Therefore, there is no need to disassemble the quartz member, and workability is improved.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
First, an outline of a semiconductor wafer processing apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a schematic longitudinal sectional view of a semiconductor wafer processing apparatus according to one embodiment of the present invention, and FIG. 10 is a schematic transverse sectional view of a semiconductor wafer processing apparatus according to one embodiment of the present invention.
[0024]
The reaction tube 101 made of quartz, silicon carbide, or alumina has a cylindrical shape having a flat space in the horizontal direction, a wafer support 200 is provided inside the reaction tube 101, and gas is introduced into both ends of the reaction tube 101 in an airtight manner. A flange 103 and a gas introduction flange 104 are provided, and one of the gas introduction flanges 103 is further provided with a transfer chamber (not shown) via a gate valve 105. Gas introduction lines 107 and 108 and exhaust lines 109 and 110 are connected to the gas introduction flange 103 and the gas introduction flange 104, respectively, and upper and lower heaters 106a and 106b are provided above and below the reaction tube 101, respectively. The inside of the tube 101 is uniformly heated. Further, a heat insulator 113 is provided so as to cover the upper heater 106a, the lower heater 106b, and the reaction tube 101.
[0025]
The gate valve 105 is opened, and the wafer 1 is carried in from the left side in the figure by a wafer transfer robot (not shown) and placed on the wafer support 200. In this example, two wafers 1 are placed on the wafer support 200.
[0026]
The wafer transfer robot retreats, the gate valve 105 is closed, the reaction gas is introduced into the reaction tube 101 from the gas introduction lines 107 and 108, and is exhausted from the exhaust lines 109 and 110. In order to ensure the uniformity of the treatment, the reaction gas flows diagonally, for example, from the gas introduction line 107 to the exhaust line 110, or from the gas introduction line 108 to the exhaust line 109, and The direction of the flow is changed every time.
[0027]
When the processing of the wafer 1 is completed, the gate valve 105 is opened, and the wafer 1 is unloaded by the wafer transfer robot.
[0028]
Next, the wafer support used in the present embodiment will be described. FIG. 1 is a schematic view of a wafer support of the present embodiment, FIG. 2 is a schematic view of a pedestal having a support of the present embodiment, and FIG. 3 is a wafer support plate and a wafer of the present embodiment. FIG. 4 is a plan view of the heat equalizing plate of the present embodiment, FIG. 6 is a schematic view of a spacer provided with a gap of the present embodiment, and FIG. FIG. 6 is a detailed cross-sectional view of a portion of the wafer support of the embodiment having a pedestal support, a spacer, a wafer support plate, and a heat equalizing plate.
[0029]
The wafer support 200 of the present embodiment is installed in a processing chamber (reaction tube 101) of a semiconductor wafer processing apparatus, and includes a pedestal 4 and a support 5 (see FIG. 2), and two wafer support plates 2 (see FIG. 3). ), And is composed of one heat equalizing plate 3 (see FIG. 4) and a spacer 6 (see FIG. 5). As shown in FIG. 2, the pedestal 4 is provided with three columns 5. It is preferable that the number of the columns 5 is three or more. As shown in FIG. 3, a hole 21 is formed in the wafer support plate 2 so as to correspond to the column 5. An opening 22 having a diameter larger than the diameter of the wafer 1 is provided at the center of the wafer support plate 2, and four wafer support members 23 projecting into the opening 22 are provided. The wafer 1 is supported by the wafer support member 23 and is supported in the opening 22. As shown in FIG. 4, the heat equalizing plate 3 is also provided with holes 31 corresponding to the columns 5. As shown in FIG. 6, the spacer 6 has a cylindrical shape, and a cylindrical hole 61 is provided at the center of the spacer 6. The inner diameter of the spacer 6 is the outer diameter of the support 5 and the hole 21 of the wafer support plate 2. Larger than the diameter of. The upper and lower surfaces of the spacer 6 are flat, and the wafer support plate 2 or the heat equalizing plate 3 and the spacer 6 are configured to be flat and in contact with each other. Notches 62 are provided on the upper and lower surfaces of the spacer 6, respectively. The cutouts 62 are provided at three locations on the upper surface and the lower surface, respectively. The notch 62 allows the outer surface of the spacer 6 to communicate with the hole 61. The pedestal 4, the support 5, the wafer support plate 2, and the soaking plate 3 are made of quartz.
[0030]
The pedestal 4, the lower wafer support plate 2, the heat equalizing plate 3, and the upper wafer support plate 2 are provided in this order from the bottom. Spacers 6 are provided between the pedestal 4 and the wafer support plate 2, between the lower wafer support plate 2 and the heat equalizing plate 3, and between the heat equalizing plate 3 and the upper wafer support plate 2, respectively. ing. The height of the wafer support plate 2 and the heat equalizing plate 3 and the distance between the wafer support plate 2 and the heat equalizing plate 3 are determined by the spacer 6. The support 5 penetrates the hole 21 of the wafer support plate 2, the hole 31 of the heat equalizing plate 3, and the hole 61 of the spacer 6.
[0031]
In the wafer support 200 assembled in this manner, as shown in FIG. 8, an etching gas or an etching solution is supplied to the space between the spacer 6 and the support post 5 through the cutout portion 62 provided in the spacer 6 during cleaning. Since it easily goes around, it is possible to prevent the occurrence of etching residue in this portion. As a result, when performing the reactive gas cleaning, the etching time can be reduced, and damage to the quartz member due to over-etching can be reduced.
[0032]
The inside of the processing chamber (reaction tube 101) is heated to about 650 ° C., a SiH ₄ gas is introduced to deposit a silicon film of about 10 μm on the inner wall of the reaction tube 101 and the wafer support 200, and then CIF is heated at about 570 ° C. Gas cleaning using _three gases was performed for 180 minutes.
[0033]
Although the etching residue was confirmed in the conventional quartz spacer 6 shown in FIG. 5, it was confirmed that there was no etching residue in the case of using the spacer 6 provided with the gap (notch portion 62) in the present embodiment. Was. Therefore, according to the present embodiment, it has become clear that the etching rate on the inner wall of the spacer 6 and the surface of the column 5 can be increased, and the etching rate distribution in the processing chamber can be made uniform.
[0034]
As described above, according to the present invention, it is possible to make the etching rate distribution uniform during gas reaction cleaning and wet cleaning. Therefore, even when all the deposits attached to the reaction tube wall surface and the wafer support are completely removed, etching and damage to the reaction tube wall surface and the wafer support surface itself are reduced, so that the yield reduction due to particle generation is reduced. It is possible to suppress and structure the productivity. Further, the frequency of replacing and wet cleaning of quartz parts such as a reaction tube can be reduced, and the downtime of the apparatus during cleaning can be shortened. Therefore, the operation rate and throughput of the apparatus can be improved, and thereby the productivity can be improved.
[0035]
【The invention's effect】
According to the present invention, there is provided a substrate processing apparatus capable of realizing an improvement in productivity and a reduction in cost by making the etching rate distribution uniform in gas reaction cleaning and wet cleaning.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an embodiment of the present invention and a wafer support of the prior art.
FIG. 2 is a schematic view of a pedestal having a pillar according to an embodiment of the present invention and a prior art.
FIG. 3 is a plan view of a wafer support plate and a wafer according to an embodiment of the present invention and a conventional technique.
FIG. 4 is a plan view of a heat equalizing plate according to an embodiment of the present invention and a conventional technology.
FIG. 5 is a schematic view of a prior art spacer.
FIG. 6 is a schematic view of a spacer provided with a gap according to an embodiment of the present invention.
FIG. 7 is a detailed sectional view of a portion of a conventional wafer support composed of a pedestal support, a spacer, a wafer support plate, and a heat equalizing plate.
FIG. 8 is a detailed cross-sectional view of a portion composed of a pedestal support, a spacer, a wafer support plate, and a heat equalizing plate of the wafer support unit according to one embodiment of the present invention.
FIG. 9 is a schematic vertical sectional view of a semiconductor wafer processing apparatus according to one embodiment of the present invention.
FIG. 10 is a schematic cross-sectional view of a semiconductor wafer processing apparatus according to one embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Wafer 2 ... Wafer support plate 3 ... Heat equalizing plate 4 ... Pedestal 5 ... Post 6 ... Spacer 21, 31, 61 ... Hole 62 ... Cutout 63 ... Reaction by-product 64 ... Inner wall 101 ... Reaction tubes 103, 104 ... Gas introduction flange 105 Gate valves 107 and 108 Gas introduction lines 109 and 110 Exhaust line 106a Upper heater 106b Lower heater 113 Insulation material 200 Wafer support

Claims (1)

A substrate processing apparatus comprising: a processing chamber for processing a substrate; and a substrate support for supporting the substrate in the processing chamber, wherein the substrate support includes a plurality of constituent members, and at least one member of the plurality of constituent members. A substrate processing apparatus provided with a guide for assisting the cleaning medium to wrap around at least a part of the space between the plurality of members.

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