JP5866595B2 - Tray for plasma processing apparatus and plasma processing apparatus - Google Patents

Description

  The present invention relates to a plasma processing apparatus tray placed in a state in which a substrate to be processed is accommodated on a substrate mounting stage provided in a reaction vessel, and a plasma processing apparatus including such a tray.

  In the plasma processing apparatus, one or a plurality of substrates to be processed are mounted on a substrate mounting table provided in a reaction vessel, and plasma processing such as plasma etching processing or plasma film forming processing is performed. In particular, when plasma processing is performed on a plurality of substrates to be processed, the plurality of substrates to be processed are placed on a single tray and transferred to a reaction container in order to improve work efficiency. The substrate to be processed that has been transported to the reaction container is placed on the substrate placing table in a state of being placed on the tray.

  When the plasma etching process is performed, heat is generated in the substrate. In the plasma film forming process, it is necessary to maintain the substrate at a predetermined temperature. Therefore, in the plasma processing apparatus, a cooling mechanism or a heating mechanism is provided on the substrate mounting table so that the substrate on the substrate mounting table is cooled or heated. In order to improve heat transfer between the substrate to be processed held on the tray and the substrate mounting table, the conventional plasma processing apparatus has an accommodation hole penetrating in the thickness direction, and accommodates the substrate in this accommodation hole. Such a tray is used (Patent Documents 1 to 3).

JP 2006-066417 A Japanese Unexamined Patent Publication No. 2007-109770 JP 2010-267894 A

  In general, a material different from the substrate to be processed is used for the tray in consideration of strength and the like. However, if the material of the tray and the substrate to be processed are different, the plasma state becomes unstable near the boundary between the tray and the substrate to be processed, and it becomes impossible to perform uniform plasma processing on the entire substrate to be processed. There is a problem that the peripheral portion of the receiving hole is consumed by plasma etching. When the peripheral portion of the tray receiving hole is consumed, the substrate to be processed cannot be held in the correct position or posture. For this reason, when the peripheral portion of the accommodation hole is consumed, the entire tray has to be replaced with a new tray even if the other portions are not consumed.

  The present invention has been made to solve the above problems, and a first object of the present invention is to provide a plasma processing apparatus tray that does not impair the uniformity of plasma processing on a substrate to be processed, and such a tray. A plasma processing apparatus including a tray is provided. A second object of the present invention is to provide a plasma processing apparatus tray and a plasma processing apparatus equipped with such a tray that can minimize the replacement part when consumed by plasma processing.

The present invention is a plasma processing apparatus tray mounted in a state in which a substrate to be processed is accommodated on an upper surface of a substrate mounting table provided in a reaction container,
A tray body mounted on the upper surface of the substrate mounting table;
An opening provided in the tray body and penetrating in the thickness direction of the tray body;
An annular substrate holding member detachably attached to the opening,
The substrate holding member is provided on the outer peripheral edge of the substrate holding member, and engages with the opening, and the outer surface of the lower surface of the substrate to be processed formed at the lower part of the inner peripheral edge of the substrate holding member. have a substrate support portion for supporting the peripheral edge,
The inner peripheral surface of the opening is formed in a tapered shape that expands from below to above,
The outer peripheral surface of the engaging portion of the substrate holding member is formed in a taper shape corresponding to the inner peripheral surface of the opening and is engaged in a manner of being placed on the inner peripheral surface of the opening .

  In the plasma processing apparatus tray of the present invention, since the tray body and the substrate holding member are separated, the materials of the tray body and the substrate holding member can be freely selected. In particular, the substrate holding member can be made of an appropriate material that does not impair the uniformity of plasma processing, for example, the same material as the substrate to be processed. By using such a plasma processing apparatus tray, the plasma state in the vicinity of the outer peripheral edge of the substrate to be processed during the plasma processing can be stabilized, and uniform plasma processing can be performed on the entire substrate to be processed.

  In the plasma processing apparatus tray of the present invention, it is preferable that the upper end portion of the substrate holding member protrudes from the upper surface of the tray body when the substrate holding member is attached to the opening of the tray body. . In such a configuration, the upper end portion of the substrate holding member that protrudes from the tray body functions as a rectifying plate that adjusts the flow rate and flow rate of the source gas supplied during the plasma processing.

The plasma processing apparatus according to the present invention, which has been made to solve the above problems,
A tray for a plasma processing apparatus having a tray body, an opening penetrating in the thickness direction of the tray body provided in the tray body, and an annular substrate holding member detachably mounted in the opening;
A substrate mounting table on which the plasma processing apparatus tray is mounted;
An electrostatic chuck provided on the substrate mounting table and electrostatically attracting the plasma processing apparatus tray.

  The tray for a plasma processing apparatus of the present invention includes a tray body and an annular substrate holding member that is detachably attached to the opening of the tray body, and the substrate to be processed is held by the substrate holding member. . Thus, since the tray main body and the substrate holding member are separated, the material of the tray main body and the substrate holding member can be freely selected so that the uniformity of the plasma processing on the substrate to be processed is not impaired. Further, even when the substrate holding member is consumed by the plasma processing, it is only necessary to replace the substrate holding member.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic which shows the whole structure of the plasma processing apparatus which concerns on the 1st Example of this invention. The longitudinal cross-sectional view (a) and external appearance perspective view (b) of a tray which were mounted on a part of board | substrate mounting base and the board | substrate mounting base. The elements on larger scale of a substrate mounting base and a tray. The cross-sectional perspective view of the opening part of a tray main body and a board | substrate holding member. The cross-sectional perspective view of the opening part of a tray main body and a board | substrate holding member which concern on 2nd Example of this invention. The cross-sectional perspective view of the opening part of a tray main body which shows the 3rd Example of this invention, a board | substrate holding member, and a board | substrate mounting base. The board | substrate mounting stand, a tray, and the elements on larger scale of a to-be-processed substrate.

  Embodiments of a plasma processing apparatus tray and a plasma processing apparatus according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of a plasma processing apparatus 1 according to a first embodiment of the present invention, and FIGS. 2 to 4 are views showing the structure of a plasma processing apparatus tray 10 (hereinafter simply referred to as “tray 10”). A plasma processing apparatus 1 according to the present embodiment performs plasma etching on a substrate 11 to be processed, and includes a vacuum vessel 2 in which a processing chamber 2a is formed, and an upper portion disposed opposite to the inside of the vacuum vessel 2. An electrode 21 and a lower electrode 22 are provided. Here, plasma etching is performed on the disk-shaped substrate 11 to be processed, but the shape of the substrate 11 to be processed is not limited to the disk shape but may be a rectangular plate shape or the like.

A dielectric layer 23 is provided on the upper surface of the lower electrode 22, and the lower electrode 22 and the dielectric layer 23 function as an electrostatic chuck portion 24. In addition, a water cooling jacket 25 in which a flow passage (not shown) for circulating a refrigerant is disposed in the lower electrode 22 is provided in the lower portion of the lower electrode 22. A refrigerant is supplied from the cooling mechanism 26 to the flow path. The lower electrode 22, the dielectric layer 23, and the water cooling jacket 25 constitute the substrate mounting table 27 of the present invention. A plurality of annular grooves 28 corresponding to the size of the substrate to be processed 11 are formed on the upper surface of the substrate mounting table 27.
Although not shown, the plasma processing apparatus 1 includes, in addition to the above, a gas supply source for generating plasma, an evacuation apparatus, a high-frequency power source for applying a high-frequency voltage to the upper electrode 21 and the lower electrode 22, and the like. Yes.

  The tray 10 has a tray main body 101 disposed on the substrate mounting table 27 and a plurality of openings 102 provided on the tray main body 101 and having an inner diameter slightly larger than the outer diameter of the substrate 11 to be processed. doing. These openings 102 penetrate the tray body 101 in the thickness direction. In these openings 102, annular substrate holding members 103 are detachably mounted. The substrate holding member 103 includes an annular portion 104 along the inner peripheral surface of the opening 102, and a substrate support portion that is provided at the lower part of the inner peripheral surface of the annular portion 104 and protrudes inward of the annular portion. 105, and an engaging portion 106 provided over the entire periphery of the outer peripheral surface of the annular portion 104. When the substrate holding member 103 is mounted in the opening 102 of the tray main body 101, the thickness dimension (vertical dimension) of the substrate holding member 103 is such that the lower end portion of the substrate holding member 103 protrudes below the lower surface of the tray main body 101. Is set.

  The tray main body 101 and the substrate holding member 103 can be manufactured from appropriate materials. For example, in the case of a structure in which the tray 10 is attracted to the substrate mounting table 27 by the electrostatic chuck portion 24 as in the plasma processing apparatus 1 of the present embodiment, the tray body 101 is preferably made of a metal material such as aluminum. When the tray main body 101 is made of a metal material, the tray main body 101 can be strongly adsorbed to the substrate mounting table 27 by the electrostatic chuck portion 24.

  In this case, the substrate 11 to be processed and the substrate holding member 103 are preferably made of the same material. According to such a configuration, the state of plasma generated in the vicinity of the outer peripheral edge of the substrate 11 to be processed is stabilized, and uniform plasma processing can be performed on the entire substrate 11 to be processed. If the substrate holding member 103 is made of the same material as the substrate 11 to be processed, the substrate holding member 103 is also subjected to plasma etching, and the substrate holding member 103 is likely to be consumed. Then, since the tray main body 101 and the substrate holding member 103 are separate bodies, it is only necessary to replace the consumed substrate holding member 103, which is more economical than the conventional case where the entire tray is replaced.

  When the substrate 11 to be processed is a conductor such as silicon, if the substrate holding member 103 is made of a dielectric material such as alumina, the substrate holding member 103 functions as a focus ring. That is, plasma can be converged on the substrate 11 to be processed, and a decrease in plasma density in the vicinity of the outer periphery of the substrate 11 to be processed can be prevented. For this reason, the uniformity of the plasma on the to-be-processed substrate 11 can be improved.

  When the substrate 11 to be processed is a compound semiconductor substrate, the tray body 101 is preferably made of a metal material, and the substrate holding member 103 is preferably made of a ceramic material such as alumina, silicon dioxide, or aluminum nitride. Since the substrate holding member 103 made of a ceramic material is difficult to be subjected to plasma etching, the consumption of the substrate holding member 103 during plasma processing can be suppressed. The tray main body 101 made of a metal material generates metal radicals by plasma processing. However, the substrate holding member 103 is interposed between the tray main body 101 and the substrate to be processed 11 so that the tray main body 101 and the substrate to be processed 11 are adjacent to each other. Therefore, the contamination of the substrate 11 to be processed by the metal radicals can be suppressed to a minimum.

The operation of the plasma processing apparatus 1 is as follows.
First, the substrate 11 to be processed is inserted into the annular portion 104 of the substrate holding member 103 from above the tray body 101, and the peripheral portion of the lower surface of the substrate 11 to be processed is placed on the substrate support portion 105. As a result, the substrate 11 to be processed is held in the lower part of the substrate holding member 103. Thereafter, the tray 10 is transported to the substrate platform 27 while being held by the transport holder 30, and is placed at a predetermined position on the substrate platform 27. At this time, the tray 10 is placed on the substrate platform 27 with the lower end of the substrate holding member 103 entering the annular groove 28. Then, after the substrate 11 to be processed is placed on the dielectric layer 23, it is separated from the substrate support portion 105. Further, the tray main body 101 is attracted by the electrostatic chuck portion 24. Subsequently, the inside of the vacuum vessel 2 is depressurized, and the source gas is introduced into the vacuum vessel 2, and a high frequency voltage is applied to the upper electrode 21 and the lower electrode 22. Thereby, the source gas is turned into plasma, and the surface of the substrate 11 to be processed is subjected to plasma processing.

  Moreover, the substrate mounting table 27 is cooled by the refrigerant flowing through the water cooling jacket 25, and the heat generated in the substrate 11 to be processed held on the tray 10 is taken away. In particular, in this embodiment, when the tray 10 is placed on the substrate platform 27, the lower end portion of the substrate holding member 103 enters the annular groove 28, so that the processing target held at the lower portion of the substrate holding member 103 is used. The lower surface of the substrate 11 and the upper surface of the substrate mounting table 27 are in contact with each other. For this reason, the heat generated in the substrate to be processed 11 is efficiently taken away by the substrate mounting table 27, and the substrate to be processed 11 can be efficiently cooled.

  FIG. 5 is a sectional perspective view of the opening of the plasma processing apparatus tray and the substrate holding member according to the second embodiment of the present invention. In this embodiment, the opening 102 of the tray main body 101 is tapered so as to expand from the lower part to the upper part, and the outer peripheral surface of the annular portion 104 of the substrate holding member 103 has a shape corresponding to the inner peripheral surface of the opening 102. The taper is configured to engage with the inner peripheral surface of the opening 102 of the tray body 101 in such a manner that the outer peripheral surface of the annular portion 104 is placed. Therefore, in this embodiment, the outer peripheral surface of the annular portion 104 becomes the engaging portion 106. Further, the inner peripheral surface of the annular portion 104 is an inclined surface that is inclined inward from the upper side to the lower side, and the substrate 11 to be processed is held on the inner peripheral surface of the annular portion 104. Therefore, the inner peripheral surface of the annular portion 104 becomes the substrate support portion 105. The substrate holding member 103 has a lower end that enters the annular groove 28.

Further, the upper end of the substrate holding member 103 is configured to protrude upward from the upper surface of the tray main body 101. A portion of the substrate holding member 103 that protrudes above the upper surface of the tray main body 101 functions as a current plate, and has an effect of adjusting the speed and concentration of the source gas flowing on the substrate 11 to be processed accommodated in the tray 10. In FIG. 5 , for the sake of convenience, the substrate holding member 103 is drawn so as to protrude by substantially the same length as the upper surface of the tray main body 101, but the length dimension of the protruding portion is the source gas provided in the vacuum vessel 2. The position may be appropriately changed according to the position of the inlet and the outlet, the position of the opening 102 provided in the tray body 101, and the like.

  6 and 7 show a third embodiment of the present invention, which differs from the first embodiment in the following points. In other words, a plurality of columnar convex portions 110 corresponding to the internal shape of the substrate holding member 103 are provided on the upper surface of the substrate mounting table 27. Inside the substrate mounting table 27, electrostatic chucks are provided at the respective convex portions 110 and other portions.

When the tray 10 is placed on the substrate mounting table 27, the convex portion 110 is disposed inside the substrate holding member 103, and the upper surface of the convex portion 110 is higher than the upper surface of the substrate supporting portion 105 of the substrate holding member 103. Located in. Therefore, the substrate 11 to be processed that has been supported by the substrate support portion 105 is pushed upward by the convex portion 110 and placed directly on the upper surface of the convex portion 110. Therefore, since the heat generated in the substrate 11 to be processed is efficiently conducted to the substrate mounting table 27, the substrate 11 to be processed can be efficiently cooled.
Further, in this embodiment, since the electrostatic chuck is also provided on each convex portion 110, not only the tray 10 but also the substrate 11 itself can be strongly electrostatically adsorbed to the convex portion 110.

In addition, this invention is not limited to an above-described Example, A various change is possible. For example, in the above embodiment, the upper end and the lower end of the substrate holding member protrude above and below the upper and lower surfaces of the tray body, but the upper and lower ends are substantially the same as the upper and lower surfaces of the tray body. It may be in a height position.
Further, a step portion may be provided on the upper or lower portion of the inner peripheral surface of the opening of the tray body, and the substrate holding member may be detachably mounted on the step portion. In this case, the thickness dimension (vertical dimension) of the substrate holding member may be made smaller than the thickness dimension of the tray body, and may be mounted on the upper half or lower half of the inner peripheral surface of the opening.

DESCRIPTION OF SYMBOLS 1 ... Plasma processing apparatus 2 ... Vacuum container 2a ... Processing chamber 10 ... Plasma processing apparatus tray 101 ... Tray main body 102 ... Opening 103 ... Substrate holding member 104 ... Annular part 105 ... Substrate support part 106 ... Engagement part 11 ... To-be-processed Substrate 21 ... Upper electrode 22 ... Lower electrode 23 ... Dielectric layer 24 ... Electrostatic chuck 25 ... Water cooling jacket 26 ... Cooling mechanism 27 ... Substrate mounting base 28 ... Annular groove

Claims (5)

A plasma processing apparatus tray placed in a state in which a substrate to be processed is accommodated on an upper surface of a substrate placement table provided in a reaction vessel,
A tray body disposed on the upper surface of the substrate mounting table;
An opening provided in the tray body and penetrating in the thickness direction of the tray body;
An annular substrate holding member detachably attached to the opening,
The substrate holding member engages with the opening provided at the outer peripheral edge of the substrate holding member, and the outer peripheral edge of the lower surface of the substrate to be processed formed at the lower part of the inner peripheral edge of the substrate holding member have a substrate support portion for supporting the,
The inner peripheral surface of the opening is formed in a tapered shape that expands from below to above,
The plasma is characterized in that the outer peripheral surface of the engagement portion of the substrate holding member is formed in a taper shape corresponding to the inner peripheral surface of the opening and is engaged with the inner surface of the opening. Tray for processing equipment.   The tray for a plasma processing apparatus according to claim 1, wherein the substrate holding member is made of the same material as the substrate to be processed. 3. The plasma processing apparatus tray according to claim 1, wherein when the substrate holding member is attached to the opening of the tray main body, an upper end portion of the substrate holding member protrudes from an upper surface of the tray main body. . A tray for a plasma processing apparatus according to any one of claims 1 to 3 ,
A substrate mounting table on which the plasma processing apparatus tray is mounted;
A plasma processing apparatus, comprising: an electrostatic chuck provided on the substrate mounting table and electrostatically attracting the tray for the plasma processing apparatus.   A convex portion corresponding to the internal shape of the substrate holding member is provided on the upper surface of the substrate mounting table, and when the plasma processing apparatus tray is mounted on the substrate mounting table, the convex portion is The plasma processing apparatus according to claim 4, wherein the plasma processing apparatus is disposed inside the substrate holding member, and an upper surface of the convex portion is positioned above an upper surface of the substrate support portion.

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