JP2023110807A - Sample holding tool - Google Patents

Abstract

To provide a sample holding tool capable of suppressing an abnormal discharge in a flow channel.SOLUTION: A sample holding tool comprises a ceramic substrate, a base plate, and an embedded member. The ceramic substrate includes: a first surface on which a processed body is mounted; a second surface that is positioned on the side opposite to the first surface; and a first flow channel that penetrates between the first surface and the second surface. The base plate is bonded to the second surface of the ceramic substrate, and includes a penetration hole at a position corresponded to at least the first flow channel. The embedded member includes a madreporic body at an end part on the first flow channel side in the penetration hole, and includes a second flow channel communicated with the first flow channel via the madreporic body. In addition, the second flow channel includes: a first portion that is vertical to the first surface; and a second portion that crosses the first portion.SELECTED DRAWING: Figure 3

Description

The disclosed embodiments relate to sample holders.

2. Description of the Related Art In the process of manufacturing semiconductor components, an electrostatic chuck is used as a sample holder that holds an object to be processed such as a semiconductor wafer to be plasma processed. This electrostatic chuck is constructed, for example, by bonding a ceramic substrate in which electrodes are embedded to a metal base plate.

The electrostatic chuck is formed with a flow path for supplying heat transfer gas for temperature control to the object to be processed placed on the electrostatic chuck. In addition, from the viewpoint of suppressing the invasion of plasma into the flow path, an electrostatic chuck has been proposed in which a porous body is arranged in the flow path (see, for example, Patent Document 1).

JP 2019-165223 A

However, in the conventional technology described above, there is room for further improvement in terms of suppressing abnormal discharge in the flow path.

One aspect of the embodiments has been made in view of the above, and an object thereof is to provide a sample holder capable of suppressing abnormal electric discharge in a channel.

A sample holder according to one aspect of an embodiment includes a ceramic substrate, a base plate, and an embedding member. The ceramic substrate has a first surface on which an object to be processed is placed, a second surface opposite to the first surface, and a first flow penetrating between the first surface and the second surface. have a road and The base plate is bonded to the second surface of the ceramic substrate and has through holes at least at positions corresponding to the first flow paths. The embedding member has a porous body at an end on the first flow path side in the through hole, and has a second flow path that communicates with the first flow path via the porous body. Also, the second channel has a first portion perpendicular to the first surface and a second portion intersecting with the first portion.

According to one aspect of the embodiment, it is possible to provide a sample holder capable of suppressing abnormal discharge in the channel.

FIG. 1 is a perspective view showing the configuration of a sample holder according to an embodiment. FIG. 2 is a schematic diagram showing a cross section of the sample holder according to the embodiment. FIG. 3 is an enlarged cross-sectional view showing the configuration of the embedding member and its surroundings according to the embodiment. FIG. 4 is a plan view showing an example of the configuration of the embedding member according to the embodiment viewed from above. FIG. 5 is an enlarged cross-sectional view showing a configuration of an embedding member and its surroundings according to Modification 1 of the embodiment. FIG. 6 is a plan view showing an example of the configuration of the embedding member according to Modification 1 of the embodiment, viewed from above. FIG. 7 is an enlarged cross-sectional view showing the configuration of an embedding member and its surroundings according to Modification 2 of the embodiment. FIG. 8 is a plan view showing an example of a configuration of an embedding member according to Modification 2 of the embodiment, viewed from above. FIG. 9 is an enlarged cross-sectional view showing a configuration of an embedding member and its surroundings according to Modification 3 of the embodiment. FIG. 10 is a plan view showing an example of a configuration of an embedding member according to Modification 3 of the embodiment, viewed from above. FIG. 11 is an enlarged cross-sectional view showing a configuration of an embedding member and its surroundings according to Modification 4 of the embodiment. FIG. 12 is a plan view showing an example of a configuration of an embedding member according to Modification 4 of the embodiment, viewed from above. FIG. 13 is an enlarged cross-sectional view showing the configuration of an embedding member and its surroundings according to Modification 5 of the embodiment. FIG. 14 is a plan view showing an example of a configuration of an embedding member according to Modification 5 of the embodiment, viewed from above.

Hereinafter, embodiments of a sample holder disclosed in the present application will be described with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below. Moreover, each embodiment can be appropriately combined within a range that does not contradict the content. Also, in each of the following embodiments, the same parts are denoted by the same reference numerals, and overlapping descriptions are omitted.

Further, in the embodiments described below, expressions such as "constant", "perpendicular", "perpendicular" or "parallel" may be used, but these expressions are strictly "constant", "perpendicular", " It does not have to be "perpendicular" or "parallel". For example, "perpendicular" means that the central axis of the first portion is 90°±2° to the first plane, and "parallel" means that the central axis of the second portion is 0°±2° to the first plane. That is, each of the expressions described above allows deviations in, for example, manufacturing accuracy and installation accuracy.

<Embodiment>
First, the configuration of a sample holder 100 according to an embodiment will be described with reference to FIGS. 1 to 4. FIG. FIG. 1 is a perspective view showing the configuration of a sample holder 100 according to an embodiment. As shown in FIG. 1, the sample holder 100 has a structure in which a ceramic substrate 110 and a base plate 120 are bonded together.

The ceramic substrate 110 uses electrostatic force to attract an object (not shown) such as a semiconductor wafer. The ceramic substrate 110 is a member obtained by forming a raw material containing ceramic into a substantially disc shape.

Ceramic substrate 110 is mainly made of, for example, aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), yttria (Y ₂ O ₃ ), cordierite, silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), or the like. included as an ingredient.

The base plate 120 is a supporting member that supports the ceramic substrate 110 . The base plate 120 is attached to, for example, a semiconductor manufacturing apparatus, and causes the sample holder 100 to function as a semiconductor holding device that holds an object to be processed such as a semiconductor wafer.

The base plate 120 is a metal circular member. As a metal material forming the base plate 120, for example, an aluminum-based composite material such as aluminum, stainless steel, titanium, or AlSiC can be used.

FIG. 2 is a schematic diagram showing a cross section of the sample holder 100 according to the embodiment. As described above, the sample holder 100 is constructed by bonding the ceramic substrate 110 and the base plate 120 together.

The ceramic substrate 110 has a first surface 110a and a second surface 110b. An object to be processed (not shown) such as a semiconductor wafer is placed on the first surface 110a. The second surface 110b is located on the side opposite to the first surface 110a.

The object to be processed placed on the first surface 110a of the ceramic substrate 110 is subjected to plasma processing by generating plasma above the first surface 110a. This plasma can be generated by applying high-frequency power to an electrode (not shown) facing the first surface 110a to excite the gas.

An electrode 111 is arranged inside the ceramic substrate 110 . Such an electrode 111 is, for example, an electrostatic adsorption electrode, and is a conductive member containing metal such as platinum, tungsten, molybdenum. In the sample holder 100, when a voltage is applied to the electrode 111, an electrostatic force is generated, and the sample holder 100 serves as an electrostatic chuck and causes the first surface 110a of the ceramic substrate 110 to attract the object to be processed by the electrostatic force.

The base plate 120 is bonded to the second surface 110b of the ceramic substrate 110. As shown in FIG. The base plate 120 may be bonded to the second surface 110b via a bonding material, for example. As such a bonding material, for example, an adhesive such as silicone resin can be used.

The base plate 120 may have a space 121 inside. Such a space 121 may be used, for example, as a coolant passage for passing a cooling medium such as cooling water or cooling gas. The base plate 120 may also function as a high-frequency electrode to which high-frequency power for plasma generation is applied.

As shown in FIG. 2, the ceramic substrate 110 is formed with a first flow path 112 penetrating between the first surface 110a and the second surface 110b.

A through hole 122 is formed at a position corresponding to at least the first channel 112 of the base plate 120 . An embedding member 130 is arranged in the through hole 122 .

Embedded member 130 is, for example, a cylindrical member made of an insulating material such as aluminum oxide (Al ₂ O ₃ ). When the second surface 110 b of the ceramic substrate 110 is provided with the recess 113 , the embedded member 130 protrudes toward the ceramic substrate 110 from the upper surface of the base plate 120 (that is, the surface bonded to the second surface 110 b ) to form the recess 113 . may be fitted to

As a result, the length of the first channel 112 is shortened at the position corresponding to the concave portion 113 of the ceramic substrate 110, so that plasma generation in the first channel 112 can be suppressed.

The embedding member 130 has a porous body 131 at the end on the first channel 112 side. Since the porous body 131 is positioned at the end on the first flow path 112 side in this way, when plasma is generated above the first surface 110a of the ceramic substrate 110, the plasma is generated in the first flow path. 112 to reach the base plate 120 side can be reduced.

Porous body 131 is, for example, alumina porous body or other ceramic porous body. The porous body 131 only needs to have voids to the extent that gas can flow. Porosity of porous body 131 is, for example, 40% or more and 60% or less.

A second channel 132 communicating with the first channel 112 via the porous body 131 is formed in the embedding member 130 . The second flow path 132 and the first flow path 112 form a continuous gas flow path from the lower surface of the base plate 120 through the porous body 131 to the upper surface (first surface 110a) of the ceramic substrate 110 .

A heat transfer gas such as, for example, helium may flow through second flow path 132 and first flow path 112 . By flowing the heat transfer gas through the second flow path 132 and the first flow path 112, the heat transfer gas is supplied to the back surface of the object to be processed placed on the first surface 110a of the ceramic substrate 110. and the ceramic substrate 110 are improved.

FIG. 3 is an enlarged cross-sectional view showing the configuration of the embedding member 130 and its surroundings according to the embodiment, and FIG. 4 is a plan view showing an example of the configuration of the embedding member 130 according to the embodiment viewed from above. is. 4 and subsequent drawings corresponding to FIG. 4 also show the position of the first flow path 112 formed in the ceramic substrate 110 (see FIG. 3) for easy understanding.

As shown in FIG. 3 and the like, in the embodiment, the second flow path 132 formed in the embedding member 130 has a first portion 132a and a second portion 132b. The first portion 132 a is a portion perpendicular to the first surface 110 a of the ceramic substrate 110 .

The second portion 132b is a portion that intersects with the first portion 132a. In other words, the second portion 132b is a portion extending in a direction different from that of the first portion 132a. For example, in the embodiment, the second portion 132b is parallel to the first surface 110a and linear.

In addition, in the embodiment, the second flow path 132 is formed by connecting the two first parts 132a with one second part 132b. As a result, the second flow path 132 has a curved shape inside the embedding member 130 .

Of the two first portions 132a, the first portion 132a directly connected to the porous body 131 is positioned so as to overlap the first flow path 112 in plan view, as shown in FIG. On the other hand, of the two first portions 132a, the first portion 132a that is not directly connected to the porous body 131 is positioned so as not to overlap the first flow path 112 in plan view.

By the way, for example, it is assumed that first flow path 112 and second flow path 132 are positioned linearly from the upper surface (first surface 110 a ) of ceramic substrate 110 to the lower surface of base plate 120 .

In this case, when plasma is generated above the first surface 110a, the charged particles in the plasma enter the first channel 112 while maintaining high energy, and the porous body 131 and the second channel 132 As a result, abnormal discharge may occur in the porous body 131 and the second flow path 132 .

On the other hand, in the embodiment, as shown in FIG. 3 and the like, the second flow path 132 has a bent structure, that is, a labyrinth structure. As a result, even if charged particles in the plasma enter the first channel 112 when plasma is generated above the first surface 110 a , the charged particles are removed from the second channel 132 . It can be deactivated by colliding with a wall.

Furthermore, in the embodiment, compared to the case where the first flow path 112 and the second flow path 132 are located in a straight line from the first surface 110a of the ceramic substrate 110 to the bottom surface of the base plate 120, the length of the entire flow path is length can be increased.

As a result, when plasma is generated above the first surface 110a, even if charged particles in the plasma enter the first channel 112, they can be deactivated in the middle of the long channel. can be done.

As described above, in the embodiment, since the second flow path 132 has a bent structure, charged particles entering the second flow path 132 can be easily deactivated. The occurrence of abnormal discharge in 112 and second flow path 132 can be suppressed.

The embedding member 130 according to the embodiment includes, for example, a cylindrical green sheet formed with a through hole corresponding to the first portion 132a and a cylindrical green sheet formed with a lateral hole corresponding to the second portion 132b. can be formed by laminating to form a laminate and firing the laminate.

In the embodiment, by arranging the second portion 132b parallel to the first surface 110a, a green sheet having a lateral hole corresponding to the second portion 132b can be easily formed. can be easily formed.

Note that the embedding member 130 according to the embodiment is formed by arranging two semi-cylindrical molded bodies each having a first portion 132a and a second portion 132b formed in a semi-cylindrical shape and crimping them so as to form a cylindrical shape. It may be formed by sintering the formed body.

In addition, the embedding member 130 according to the embodiment is formed by using a 3D printer to produce a cylindrical molded body in which the first portion 132a and the second portion 132b are formed, and firing the molded body. good too.

<Modification 1>
Next, various modifications of the embodiment will be described with reference to FIGS. 5 to 14. FIG. FIG. 5 is an enlarged cross-sectional view showing the configuration of the embedding member 130 according to Modification 1 of the embodiment and its surroundings, and FIG. FIG. 2 is a plan view showing an example of the configuration;

As shown in FIG. 5 and the like, in the sample holder 100 according to Modification 1, the configuration of the second channel 132 is different from that of the above embodiment. Specifically, in Modification 1, the second portion 132b of the second flow path 132 is located at an angle with respect to the first portion 132a and the first surface 110a.

In this way, when plasma is generated above the first surface 110 a and charged particles in the plasma enter the first channel 112 , the charged particles are prevented from reaching the wall surface of the second channel 132 . It can be deactivated by colliding with it.

Further, in Modification 1, even if the charged particles in the plasma enter the first channel 112, they can be deactivated in the middle of the long channel. Therefore, according to Modification 1, the occurrence of abnormal discharge in first flow path 112 and second flow path 132 can be suppressed.

<Modification 2>
FIG. 7 is an enlarged cross-sectional view showing the configuration of the embedding member 130 according to Modification 2 of the embodiment and its surroundings, and FIG. FIG. 2 is a plan view showing an example of the configuration; As shown in FIG. 7, in Modification 2, the second flow path 132 has three first portions 132a and two second portions 132b.

Of the three first portions 132a, the first portion 132a directly connected to the porous body 131 and the first portion 132a farthest from the porous body 131 overlap the first flow path 112 in plan view, as shown in FIG. located. On the other hand, among the three first portions 132a, the middle first portion 132a is positioned so as not to overlap the first flow path 112 in plan view.

In Modification 2, the second flow path 132 is formed by connecting the three first parts 132a with two second parts 132b. Thereby, the second flow path 132 of Modification 2 has a shape in which a plurality of portions are bent in the middle.

Thus, when plasma is generated above the first surface 110 a and charged particles in the plasma enter the first channel 112 , the charged particles collide with the wall surface of the second channel 132 . can be effectively deactivated.

Furthermore, in Modification 2, compared to the case where the first flow path 112 and the second flow path 132 are located in a straight line from the first surface 110a of the ceramic substrate 110 to the lower surface of the base plate 120, the entire flow path is The length can be even longer.

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, they are effectively deactivated in the middle of the longer channel. be able to.

Thus, in Modification 2, the second flow path 132 has a structure that bends at a plurality of locations, thereby effectively suppressing the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132. can be done.

Although the example of FIG. 7 shows the case where the second flow path 132 has three first parts 132a and two second parts 132b, the present disclosure is not limited to such an example, and the second flow path 132 may have four or more first portions 132a and three or more second portions 132b.

<Modification 3>
FIG. 9 is an enlarged cross-sectional view showing the configuration of the embedding member 130 according to Modification 3 of the embodiment and its surroundings, and FIG. FIG. 2 is a plan view showing an example of the configuration;

As shown in FIG. 9 and the like, in Modification 3, both of the two first portions 132a are positioned so as not to overlap the first flow path 112 in plan view. For example, one first portion 132a is positioned close to the peripheral edge of the porous body 131, and the other first portion 132a is positioned close to the peripheral edge of the porous body 131 on the opposite side of the one first portion 132a. do.

As a result, in Modification 3, when charged particles in the plasma enter the first flow path 112 when plasma is generated above the first surface 110a, the charged particles are removed from the porous body 131. It can be effectively deactivated by colliding with the wall surface of the gap or the wall surface of the second channel 132 .

Furthermore, in the third modification, compared to the case where the first flow path 112 and the second flow path 132 are located in a straight line from the first surface 110a of the ceramic substrate 110 to the lower surface of the base plate 120, the entire flow path is The length can be even longer.

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, they are effectively deactivated in the middle of the longer channel. be able to.

Thus, in Modification 3, by arranging the first portion 132a of the second flow path 132 so as not to overlap the first flow path 112 in plan view, the first flow path 112 and the second flow path 132 can effectively suppress the occurrence of abnormal discharge.

<Modification 4>
FIG. 11 is an enlarged cross-sectional view showing the configuration of the embedding member 130 according to Modification 4 of the embodiment and its surroundings, and FIG. FIG. 2 is a plan view showing an example of the configuration; As shown in FIG. 12, in Modification 4, the second portion 132b is bent in plan view.

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, the charged particles collide with the wall surface of the second channel 132. can be effectively deactivated.

Furthermore, in Modification 4, compared to the case where the first flow path 112 and the second flow path 132 are located in a straight line from the first surface 110a of the ceramic substrate 110 to the lower surface of the base plate 120, the entire flow path is The length can be even longer.

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, they are effectively deactivated in the middle of the longer channel. be able to.

In this way, in Modification 4, the second portion 132b has a further curved structure, so that the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be effectively suppressed.

<Modification 5>
FIG. 13 is an enlarged cross-sectional view showing the configuration of the embedding member 130 according to Modification 5 of the embodiment and its surroundings, and FIG. FIG. 2 is a plan view showing an example of the configuration;

As shown in FIG. 13, in this modification 5, the second portion 132b is bent when viewed from the side. Further, in Modification 5, the second portion 132b has a portion through which the medium flows in the direction away from the first surface 110a (downward in FIG. 13).

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, the charged particles are caused to collide with the wall surface of the second channel. can be effectively deactivated by

Furthermore, in the fifth modification, compared to the case where the first flow path 112 and the second flow path 132 are located in a straight line from the first surface 110a of the ceramic substrate 110 to the lower surface of the base plate 120, the entire flow path is The length can be even longer.

As a result, when plasma is generated above the first surface 110a and charged particles in the plasma enter the first channel 112, they are effectively deactivated in the middle of the longer channel. be able to.

As described above, in the fifth modification, the medium is allowed to flow in the direction away from the first surface 110a, thereby effectively suppressing the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132. can be done.

A sample holder 100 according to an embodiment includes a ceramic substrate 110 , a base plate 120 and an embedding member 130 . The ceramic substrate 110 includes a first surface 110a on which an object to be processed is placed, a second surface 110b opposite to the first surface 110a, and a second surface 110b penetrating between the first surface 110a and the second surface 110b. 1 channel 112 . The base plate 120 is bonded to the second surface 110 b of the ceramic substrate 110 and has through holes 122 at least at positions corresponding to the first flow paths 112 . The embedding member 130 has a porous body 131 at the end of the through hole 122 on the side of the first flow path 112 , and a second flow path 132 communicating with the first flow path 112 via the porous body 131 . have Also, the second flow path 132 has a first portion 132a perpendicular to the first surface 110a and a second portion 132b intersecting with the first portion 132a. Thereby, the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be suppressed.

Also, in the sample holder 100 according to the embodiment, the second portion 132b is parallel to the first surface 110a. Thereby, the embedding member 130 can be formed easily.

Moreover, in the sample holder 100 according to the embodiment, the second channel 132 has a plurality of second parts 132b. Thereby, the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be effectively suppressed.

In addition, in the sample holder 100 according to the embodiment, the first channel 112 and the first portion 132a of the second channel 132 are positioned so as not to overlap each other in plan view. Thereby, the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be effectively suppressed.

Moreover, in the sample holder 100 according to the embodiment, the second portion 132b is bent in plan view. Thereby, the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be effectively suppressed.

In addition, in the sample holder 100 according to the embodiment, the second portion 132b has a portion through which the medium flows in the direction away from the first surface 110a. Thereby, the occurrence of abnormal discharge in the first flow path 112 and the second flow path 132 can be effectively suppressed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the above embodiment, an example in which the porous body 131 is provided on the embedding member 130 has been described, but the present disclosure is not limited to such an example, and the porous body 131 may be provided on the ceramic substrate 110 .

Further advantages and other aspects can be easily derived by those skilled in the art. Therefore, the broader aspects of the invention are not limited to the specific details and representative embodiments so shown and described. Accordingly, various changes may be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and equivalents thereof.

100 sample holder 110 ceramic substrate 110a first surface 110b second surface 112 first channel 120 base plate 122 through-hole 130 embedding member 131 porous body 132 second channel 132a first part 132b second part

Claims (6)

a ceramic substrate;
a base plate;
an embedded member;
The ceramic substrate has a first surface on which an object to be processed is placed, a second surface opposite to the first surface, and a first flow penetrating between the first surface and the second surface. having a road and
the base plate is bonded to the second surface of the ceramic substrate and has a through hole at least at a position corresponding to the first flow path;
The embedding member has a porous body at an end portion of the through-hole on the side of the first flow path, and has a second flow path that communicates with the first flow path via the porous body. ,
The second flow path is
a first portion perpendicular to the first plane;
and a second portion that intersects with the first portion. The sample holder according to Claim 1, wherein the second portion is parallel to the first surface. The sample holder according to claim 1 or 2, wherein the second channel has a plurality of the second parts. The sample holder according to any one of claims 1 to 3, wherein the first channel and the first part of the second channel are positioned so as not to overlap each other in plan view. The sample holder according to any one of claims 1 to 4, wherein the second portion is bent in plan view. The sample holder according to any one of claims 1 to 5, wherein the second portion has a portion through which the medium flows in a direction away from the first surface.

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