WO2012030143A2

WO2012030143A2 - Susceptor and method for manufacturing the same

Info

Publication number: WO2012030143A2
Application number: PCT/KR2011/006410
Authority: WO
Inventors: Min Sung Kim; Kyoung Hoon Chai
Original assignee: Lg Innotek Co., Ltd.
Priority date: 2010-09-01
Filing date: 2011-08-30
Publication date: 2012-03-08
Also published as: WO2012030143A3; KR20120057731A

Abstract

A method for manufacturing a susceptor is provided. In the method, a carbon material is placed in a silicon carbide molded body, and the silicon carbide molded body having therein the carbon material is subjected to hot pressing.

Description

SUSCEPTOR AND METHOD FOR MANUFACTURING THE SAME

The present disclosure relates to a susceptor and a method for manufacturing the same.

In a semiconductor process or the like, a substrate or a wafer is placed on a susceptor for deposition, etching, and the like. The susceptor may include silicon carbide having a high level of heat resistance so as to withstand conditions like high temperature or the like. The susceptor may be formed by depositing a silicon carbide layer on the outer surface of a body containing graphite using chemical vapor deposition (CVD).

However, the susceptor including the silicon carbide layer formed by the CVD process may have impaired heat conductivity due to the uneven thickness of the silicon carbide layer, or may experience cracking or separation of the silicon carbide layer when repeatedly used. Furthermore, this separate CVD process may bring about a rise in price for susceptors in the manufacture thereof.

Embodiments provide methods of manufacturing susceptors, capable of manufacturing susceptors with excellent properties, and susceptors manufactured by the methods.

In one embodiment, a method for manufacturing a susceptor, comprises: placing a carbon material in a silicon carbide molded body; and subjecting the silicon carbide molded body having therein the carbon material to hot pressing.

The silicon carbide molded body may comprise: a first part having a concave portion providing a space to be filled with the carbon material; and a second part covering the first part.

Assuming that a thickness of the first part at the concave portion is a first thickness, and a thickness of the first part other than the concave portion is a second thickness, a ratio of the first thickness to the second thickness may be in a range of 5% to 95%.

The second part may have a plate shape. The second part may have a circular plate shape.

A hot-pressing sintering apparatus used in the method for manufacturing the susceptor comprises: a chamber; a mold member in the chamber; a pressing member in the mold member, the pressing member comprising an upper pressing member and a lower pressing member for pressing; and a heating member heating the inside of the chamber.

The placing of the carbon material in the silicon carbide molded body may comprise: placing the first part on the lower pressing member; placing the carbon material in the concave portion of the first part; and placing the second part on the first part and the carbon material.

In the hot pressing, the upper pressing member may be placed on the second part such that the silicon carbide molded body having therein the carbon material is pressed by the lower pressing member and the upper pressing member while being heated by the heating member.

The hot pressing may be performed at a temperature of at least 2000℃. The hot pressing may be performed at a pressure of between 10 MPa and 50 MPa.

The method may further comprise preliminarily pressing the silicon carbide molded body between the placing of the carbon material and the hot pressing.

The carbon material may be in the form of powder or a molded body shaped corresponding to the concave portion.

In another embodiment, a susceptor may be manufactured by the method for manufacturing a susceptor described above, and have a heat conductivity of at least 180 W/mK.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.

In the method for manufacturing a susceptor according to the embodiments, a silicon carbide body is formed simultaneously with a graphite body by hot pressing without performing a separate process (e.g., CVD) for forming a silicon carbide layer, and accordingly, the process can be simplified.

The thickness of a silicon carbide molded body and the thickness of a concave portion can be controlled to thereby freely control the thicknesses of the silicon carbide body and the graphite body, the specific gravity of the susceptor, and the like. Furthermore, since the silicon carbide body having a predetermined thickness is formed on the outer surface of the graphite body by hot pressing, the silicon carbide body can be formed to have uniform thickness. Accordingly, heat conductivity can be enhanced, and cracking, separation or the like of the silicon carbide body can be prevented, thus increasing the useful lifespan of the susceptor.

Fig. 1 is a schematic view illustrating a hot-pressing sintering apparatus applicable to a method for manufacturing a susceptor according to an embodiment.

Fig. 2 is a perspective view illustrating a silicon carbide molded body used in the method for manufacturing a susceptor according to the embodiment of FIG. 1.

Fig. 3 is a perspective view illustrating a susceptor according to the embodiment of Fig. 1.

Fig. 4 is a cross-sectional view taken along line IV-IV'of Fig. 3.

Fig. 5 is a schematic view illustrating a hot-pressing sintering apparatus applicable to a method for manufacturing a susceptor according to another embodiment.

Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings.

In the descriptions of embodiments, it will be understood that when a layer (or film), a region, a pattern, or a structure is referred to as being `on/above/over/upper` substrate, each layer (or film), a region, a pad, or patterns, it can be directly on substrate each layer (or film), the region, the pad, or the patterns, or intervening layers may also be present. Further, it will be understood that when a layer is referred to as being `under/below/lower` each layer (film), the region, the pattern, or the structure, it can be directly under another layer (film), another region, another pad, or another patterns, or one or more intervening layers may also be present.

In the figures, a dimension of each of elements may be exaggerated for clarity of illustration, and the dimension of each of the elements may be different from an actual dimension of each of the elements.

Fig. 1 illustrates a non-limitative example of a hot-pressing sintering apparatus applicable to a method for manufacturing a susceptor according to an embodiment, and, of course, variously structured hot-pressing sintering apparatuses can be used.

Referring to Fig. 1, a hot-pressing sintering apparatus 100 according to an embodiment includes a chamber 10 maintaining a vacuum therein, a mold member 20 located inside the chamber 10, a pressing member 30, a heating member 40, and an insulating member 50. This will now be described in more detail.

The chamber 10 may be sealed in order to maintain a vacuum, which can thus prevent the oxidation of the heating member 40 and the like located within the chamber 10 while preventing the introduction of impurities to raw materials during a sintering process.

In order to maintain a vacuum, a vacuum pump 102 for a vacuum state is provided outside the chamber 10, and the vacuum pump 102 and the chamber 10 may be connected together through a valve 104 and an exhaust pipe 106. Thus, by selectively exhausting air, the inside of the chamber 10 can be maintained at a predetermined level of vacuum. Furthermore, a separate gas feeding source (not shown), a valve (not shown), and an inlet (not shown) may be provided for injecting an inert gas into the chamber 10.

A silicon carbide molded body 60 and a carbon material 200 are placed in the mold member 20 located within the chamber 10. Here, the silicon carbide molded body 60 and the carbon material 200 are raw materials for manufacturing a susceptor according to this embodiment.

The pressing member 30 pressing the raw materials in the mold member 20 may include a lower pressing member 31 positioned under the raw materials, and an upper pressing member 32 positioned above the raw material. The pressing member 30 may be formed of a material which is resistant to high temperature and may include graphite for example.

In this case, a high-purity graphite plate and/or graphite sheet 31a including, for example, 99.99% to 99.9999% graphite, may be placed on the top surface of the lower pressing member 31. Likewise, a high-purity graphite plate and/or graphite sheet 32a including, for example, 99.99% to 99.9999% graphite, may be placed on the bottom surface of the upper pressing member 32.

The heating member 40 heating the inside of the chamber 10 (particularly, the raw material within the mold member 20) is located outside the mold member 20. Various methods allowing the mold member 20 to be heated may be applied to the heating member 202. For example, the heating member 40 may include graphite to generate heat by external power, thus heating the mold member 20.

The insulating member 50 between the heating member 40 and the chamber 10 serves to maintain the mold member 20 at a suitable temperature during reaction. The insulating member 50 may include graphite so as to withstand high temperature.

A method for manufacturing a susceptor according to this embodiment may include: placing the carbon material 200 inside the silicon carbide molded body 60, preliminarily pressing the silicon carbide molded body 60, which has therein the carbon material 200, by using the hot-pressing sintering apparatus 100, and subjecting hot-pressing thereto.

Firstly, the operation in which the carbon material 200 is placed inside the silicon carbide molded body 600 will now be described.

Referring to Fig. 2 as well as Fig. 1, the silicon carbide molded body 60 according to this embodiment may include a first part 61 having a concave portion 64 that provides a space to be filled with the carbon material 200, and a second part 62 covering the first part 61. The second part 62 may be in the form of a plate having a flat surface toward the first part 61, for example, a circular plate.

As a result, hot-pressing can be carried out in the state where the carbon material 200 is stably placed and the first and

second parts

61 and 62 form an outer edge.

Assuming that the thickness of the first part 61 at the concave portion 64 is a first thickness, and the thickness of the first part 61 other than the concave portion 64 is a second thickness, the ratio of the first thickness to the second thickness may be 5% to 95%. The thickness ratio of less than 5% may impair stability in a hot-pressing process due to the insufficient first thickness of the first part 61 at the concave portion 64. The thickness ratio exceeding 95% may impair durability of a manufactured susceptor due to an insufficient amount of carbon material 200.

According to this embodiment, the carbon material 200 may be in the form of powder. Alternatively, the carbon material 200 may be in the form of a molded body shaped corresponding to the concave portion 64 of the first part 61. The carbon material 200 in the form of a molded body may be formed by molding carbon powder such as graphite powder using a cold isostatic press (CIP), a press, or the like.

Here, the first and

second parts

61 and 62 may be produced by molding silicon carbide having a purity of at least 5N in a press or a CIP. The carbon material 200 may have a grain size of between 0.3㎛ and 500 ㎛ for example, and a purity of at least 2N. As described above, the silicon carbide molded body 60 including high-purity silicon carbide and the carbon material 200 are used in this embodiment, and thus manufactured susceptors can have enhanced properties.

In order to place the carbon material 200 inside the silicon carbide molded body 60, the first part 61 may be located on the lower pressing member 31, the carbon material 200 may be located in the concave portion 64 of the first part 61, and the second part 62 may be located on the first part 61 and the carbon material 200.

Subsequently, the silicon carbide molded body 60 filled with the carbon material 200 is subjected to preliminary pressing and then hot pressing using the hot-pressing sintering apparatus 100.

The silicon carbide molded body 60 filled with the carbon material 200 may be preliminarily pressed at a pressure level corresponding to 10% and 100% of pressure applied in the subsequent hot pressing process. However, this preliminary pressing is not an essential operation, and may or may not be carried out, as desired.

Thereafter, while high temperature is maintained by the heating member 40, the upper pressing member 32 is placed onto the second part 62, and the carbon material 200 within the silicon carbide molded body 60 is then pressed using the upper and lower

pressing members

31 and 32. In this manner, the silicon carbide molded body 70 and the carbon material 200 are sintered into desired shapes by high temperature and high pressure (see Figs. 3 and 4).

The above hot-pressing operation may be carried out at a temperature of at least 2000℃ under a pressure of between 10 MPa and 50 MPa for one to ten hours. The temperature, pressure and time are optimized for formation of a susceptor. However, embodiments are not limited thereto, and the temperature, pressure and/or time may be variously set provided that they allow for formation of a susceptor from the silicon carbide molded body 60 and the carbon material 200 through hot pressing.

*After the hot-pressing, the manufactured susceptor may be subjected to an additional process such as processing, washing or the like.

Referring to Figs. 3 and 4, a susceptor 300 manufactured by the manufacturing method described above includes a graphite body 302 including graphite, and a silicon carbide body 304 surrounding the outer surface of the graphite body 302. The graphite body 302 is formed by subjecting to hot pressing the carbon material 200 of Fig. 2 in the form of powder or in the form of a molded body shaped corresponding to the concave portion 64 of Fig. 2. Also, the silicon carbide body 304 is formed by sintering the silicon carbide molded body 60 of Fig. 2 through the hot pressing.

As described above, since the hot pressing operation also forms the silicon carbide body 304 surrounding the outer surface of the graphite body 302 according to this embodiment, the process can be simplified as compared to the related art method in which a graphite body is formed by hot pressing and a silicon carbide layer is then formed by a separate process such as chemical vapor deposition (CVD). Accordingly, the manufacturing costs can be saved.

Furthermore, the thickness of the silicon carbide body 304 may be adjusted by adjusting the thickness of the silicon carbide molded body 60. Furthermore, the amount of carbon material 200 being provided in the concave portion 64 of Fig. 2 may be controlled by adjusting the height of the concave portion 64 of the first part 61 of Fig. 2. Consequently, the thickness of the graphite body 302 can be freely controlled, and thus the specific gravity of the susceptor 300 can also be freely controlled.

Also, the thickness of the silicon carbide body 304 may be formed to be more uniform as compared to that formed by the CVD technique. Accordingly, heat conductivity can be enhanced, and cracking, separation or the like does not occur.

For example, a susceptor provided with a silicon carbide layer by a related art chemical vapor deposition method may have a useful lifespan of about 1 to 60 times, a heat conductivity of 127 W/mK, and a specific gravity of 1.8 g/cm³. In contrast, the susceptor according to this embodiment may have a useful life span of at least 200 times, a heat conductivity of at least 180 W/mK, and a specific gravity of between 1.8 g/cm³ to 3.1 g/cm³. The susceptor according to this embodiment has superior lifespan and heat conductivity as compared to a related art susceptor, and may be variously varied in terms of specific gravity according to required properties.

Hereinafter, a method for manufacturing a susceptor according to another embodiment will be described with reference to Fig. 5. A description of like or similar parts to those of the previous embodiment may be omitted for clarity and simplicity.

The method for manufacturing a susceptor according to another embodiment may utilize a hot-pressing sintering apparatus 102 applicable to the method for manufacturing a susceptor according to another embodiment.

The method for manufacturing a susceptor according to another embodiment may include placing a carbon material 200 in a silicon carbide molded body 61, and subjecting hot pressing thereto.

In detail, the hot pressing may include placing a silicon carbide material 63 on the silicon carbide molded body 61 having therein the carbon material 200, and subjecting the silicon carbide molded body 61 having therein the carbon material 200 and the silicon carbide material 63 to hot pressing.

Here, the silicon carbide material 63 may be in the form of powder. The silicon carbide material 63 may be a silicon carbide powder having a purity of at least 5N.

The silicon carbide material 63 may be placed on the carbon material 63. Thus, a silicon carbide body 304 surrounding the outer surface of a graphite body 302 may be provided afterwards.

The features, structures, effects and the like described in the above embodiments are included in at least one embodiment, but not limited to only one embodiment. Furthermore, the features, structures, effects and the like exemplified in each embodiment may be modified and combined in other embodiments by those skilled in the art. Accordingly, such combinations and modifications should be construed as falling within the scope of the principles of this disclosure.

Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.

Claims

A method for manufacturing a susceptor, the method comprising:

placing a carbon material in a silicon carbide molded body; and

subjecting the silicon carbide molded body having therein the carbon material to hot pressing.
The method according to claim 1, wherein the silicon carbide molded body comprises:

a first part having a concave portion providing a space to be filled with the carbon material; and

a second part covering the first part.
The method according to claim 2, wherein assuming that a thickness of the first part at the concave portion is a first thickness, and a thickness of the first part other than the concave portion is a second thickness, a ratio of the first thickness to the second thickness is in a range of 5% to 95%.
The method according to claim 2, wherein the second part has a plate shape.
The method according to claim 4, wherein the second part has a circular plate shape.
The method according to claim 2, wherein a hot-pressing sintering apparatus used in the method for manufacturing the susceptor comprises: a chamber; a mold member in the chamber; a pressing member in the mold member, the pressing member comprising an upper pressing member and a lower pressing member for pressing; and a heating member heating the inside of the chamber,

wherein the placing of the carbon material in the silicon carbide molded body comprises:

placing the first part on the lower pressing member;

placing the carbon material in the concave portion of the first part; and

placing the second part on the first part and the carbon material.
The method according to claim 6, wherein in the hot pressing, the upper pressing member is placed on the second part such that the silicon carbide molded body having therein the carbon material is pressed by the lower pressing member and the upper pressing member while being heated by the heating member.
The method according to claim 1, wherein the hot pressing is performed at a temperature of at least 2000℃.
The method according to claim 1, wherein the hot pressing is performed at a pressure of between 10 MPa and 50 MPa.
The method according to claim 1, further comprising preliminarily pressing the silicon carbide molded body between the placing of the carbon material and the hot pressing.
The method according to claim 2, wherein the carbon material is in the form of powder or a molded body shaped corresponding to the concave portion.
A susceptor manufactured by the method for manufacturing a susceptor according to any one of claims 1 to 11, the susceptor having a heat conductivity of at least 180 W/mK.
The method according to claim 1, wherein the hot pressing comprises:

placing a silicon carbide material on the silicon carbide molded body having therein the carbon material; and

subjecting the silicon carbide molded body having therein the carbon material, and the silicon carbide material to hot pressing.
The method according to claim 13, wherein the silicon carbide material is in the form of powder.
The method according to claim 14, wherein the silicon carbide material is placed on the carbon material.