KR20120088460A - Deposition apparatus - Google Patents

Abstract

PURPOSE: A deposition apparatus is provided to prevent impurities from permeating into a substrate mounted on a susceptor lower plate by forming the protrusion on a susceptor upper plate and improving adhesion between the impurities and the susceptor upper plate. CONSTITUTION: A chamber(10) is formed in the shape of a cylinder or a square box. Heating elements(60) are arranged at regular distances to uniformly heat a wafer(50). A heat insulation unit(20) is formed to effectively deliver the hear from the heating element to a susceptor. The susceptor includes a susceptor upper plate(37), a susceptor lower plate(38) and a susceptor side plate. A wafer holder(40) is located on the susceptor lower plate to fix the wafer.

Description

Deposition apparatus {DEPOSITION APPARATUS}

The present disclosure relates to a deposition apparatus.

In general, chemical vapor deposition (CVD) is widely used in the art of forming various thin films on a substrate or a wafer. The chemical vapor deposition method is a deposition technique involving a chemical reaction, and forms a semiconductor thin film, an insulating film, or the like on the wafer surface by using a chemical reaction of a source material.

Such a chemical vapor deposition method and deposition apparatus has recently been attracting attention as a very important technology among thin film formation technologies due to the miniaturization of semiconductor devices, development of high efficiency, high power LED, and the like. Currently, it is used to deposit various thin films such as silicon film, oxide film, silicon nitride film or silicon oxynitride film, tungsten film and the like on a wafer.

In particular, the Hot Wall Chemical Vapor Deposition (HW-CVD) apparatus using a high temperature wall reactor becomes a passage of gas and includes a susceptor for fixing the wafer. A deposit adheres to such susceptors, or unwanted impurities are generated to cause defects on the wafer.

The embodiment is to provide a deposition apparatus that can increase the reliability of the deposition process, and can form a high quality thin film.

Deposition apparatus according to the embodiment, the chamber; A susceptor provided in the chamber and a wafer holder positioned in the susceptor, the susceptor comprising: a susceptor top plate; And a susceptor lower plate facing the susceptor upper plate, wherein the susceptor upper plate includes a protrusion.

In the deposition apparatus according to the embodiment, a protrusion is formed on the top plate of the susceptor to increase adhesion between impurities and the susceptor top plate. As a result, it is possible to prevent a phenomenon in which impurities penetrate into the substrate mounted on the susceptor lower plate to generate a defect.

In addition, by varying the density of the susceptor upper plate and the susceptor lower plate, it is possible to prevent a phenomenon in which silicon droplets are generated by reacting excess silicon atoms with the substrate after the deposition process.

Thereby, the reliability of a vapor deposition process can be improved and a high quality thin film can be formed.

1 is a cross-sectional view of a deposition apparatus according to an embodiment.
2 is a perspective view illustrating a susceptor.
3 is an enlarged perspective view illustrating A of FIG. 2.

In the description of embodiments, each layer, region, pattern, or structure may be “on” or “under” the substrate, each layer, region, pad, or pattern. Substrate formed in ”includes all formed directly or through another layer. Criteria for the top / bottom or bottom / bottom of each layer will be described with reference to the drawings.

The thickness or the size of each layer (film), region, pattern or structure in the drawings may be modified for clarity and convenience of explanation, and thus does not entirely reflect the actual size.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

A deposition apparatus according to an embodiment will be described in detail with reference to FIGS. 1 to 3. 1 is a cross-sectional view of a deposition apparatus according to an embodiment, FIG. 2 is a perspective view illustrating a susceptor, and FIG. 3 is an enlarged perspective view of A of FIG. 2.

FIG. 2 is a perspective view illustrating only the susceptor portion in FIG. 1, and a cross section taken along the line II of FIG. 2 corresponds to a cross-sectional view of FIG. 1.

1 and 2, a deposition apparatus according to an embodiment includes a chamber 10, a heat generating element 60, a thermal insulation unit 20 that maintains heat, a susceptor 30, and a susceptor 30. It may include a wafer holder 40 provided.

This will be described in more detail as follows.

The chamber 10 is formed in a cylindrical or rectangular box shape, and a predetermined space is provided inside the chamber 10 so as to process the wafer 40. Although not shown in the drawings, one side of the chamber 10 may further include a gas supply unit for introducing a precursor and a gas discharge unit for discharging the gas.

The chamber 10 serves to prevent the inflow of gas to the outside and maintain the degree of vacuum. To this end, the chamber 10 may include quartz having high mechanical strength and excellent chemical durability.

Subsequently, the heating element 60 may be provided outside the chamber 10.

The heating element 60 may be a resistive heating element that generates heat when power is applied, and may be disposed at regular intervals to uniformly heat the wafer 50. That is, in order to arrange the heat generating element 60 in a predetermined form, it may have a wire form. In one example, the heating element 60 may include a filament, a coil or a carbon wire.

Subsequently, the thermal insulation unit 20 may be provided in the chamber 10. The thermal insulation unit 20 may serve to preserve heat in the chamber 10. In addition, the heat generated from the heat generating element 60 is formed to be effectively transmitted to the susceptor 30.

The thermal insulation unit 20 is formed of a chemically stable material without deformation due to heat generated from the heat generating element 60. For example, the thermal insulation unit 20 may be formed of a nitride ceramic, a carbide ceramic, or a graphite material.

Subsequently, the susceptor 30 is positioned on the thermal insulation unit 20.

In the deposition apparatus according to the embodiment, the wafer 50 or the like on which the deposit is formed or the epitaxial growth occurs is placed on the susceptor 30.

Referring to FIG. 2, the susceptor 30 may include a susceptor upper plate 37, a susceptor lower plate 38, and a susceptor side plate 36. In addition, the susceptor upper plate 37 and the susceptor lower plate 38 face each other.

The susceptor 30 may be manufactured by positioning the susceptor upper plate 37 and the susceptor lower plate 38 and then placing the susceptor side plates 36 on both sides thereof.

However, since the embodiment is not limited thereto, a space for the gas passage may be manufactured in the susceptor 30 of the rectangular parallelepiped.

The susceptor lower plate 38 may include a wafer holder 40 capable of fixing the wafer 50 to be deposited.

In the space between the susceptor top plate 37 and the susceptor bottom plate 38, a vapor deposition process may be performed. The susceptor side plate 36 serves to prevent the reaction gas from escaping when air flows inside the susceptor 30.

The susceptor top plate 37 includes a protrusion 33. The protrusion 33 is formed on the lower surface of the susceptor upper plate 37, that is, the surface facing the susceptor lower plate 38 at the susceptor upper plate 37.

In particular, during hot wall chemical vapor deposition (HW-CVD) growth, a large amount of unwanted precipitates are generated in the susceptor top plate 37 due to the influence of airflow inside the susceptor 30. These deposits may fall into the wafer 50 causing an unintended reaction, which may cause defects in the wafer 50.

In the present exemplary embodiment, the protrusion 33 is formed on the susceptor top plate 37 to increase the surface area of the susceptor top plate 37 to increase the adhesion between the precipitate and the susceptor top plate 37. That is, the strong adhesion of the susceptor top plate 37 and the precipitate may prevent the precipitate from falling onto the wafer 50.

Therefore, this enables to obtain a high quality thin film with reduced defects.

The protrusion 33 may have a width W of 0.1 to 1 mm and a thickness T of 0.1 to 1 mm. When the width W and the thickness T of the protrusion 33 are smaller than 0.1 mm or larger than 1 mm, the surface area of the susceptor upper plate 37 does not increase much, so that the adhesion between the precipitate and the susceptor upper plate 37 is increased. It is difficult to see this increasing effect.

For example, the protrusion 33 may have a cylindrical shape as shown in FIG. 3. However, the exemplary embodiment is not limited thereto, and may include protrusions 33 having various shapes that may increase the surface area such as a spherical shape, a semicircle shape, and a polygonal shape.

The susceptor 30 includes graphite having high heat resistance and easy processing to withstand conditions such as high temperature. Since such graphite is a porous body, there is a possibility of releasing occlusion gas during the deposition process. In addition, there is a problem in that the susceptor surface is changed to silicon carbide due to the reaction between the graphite and the source gas, so that the susceptor's film may contain silicon carbide.

Specifically, the susceptor lower plate 38 may include a silicon carbide film 35 on the substrate 34 including graphite. In addition, the susceptor top plate 37 may include a protrusion 33 including silicon carbide on the substrate 32 including graphite. At this time, the protrusion 33 may be manufactured by depositing silicon carbide on the substrate 32 including graphite, and then forming the silicon carbide portion into the shape of the protrusion 33.

However, since the embodiment is not limited thereto, the susceptor top plate 37 may be manufactured by forming a silicon carbide film on a substrate including graphite, and then may form a protrusion 33 on the silicon carbide film. That is, the protrusion 33 may be manufactured separately and then attached to the susceptor top plate 37.

Subsequently, the susceptor upper plate 37 and the susceptor lower plate 38 include graphite, and the susceptor upper plate 37 and the susceptor lower plate 38 are formed to have different densities.

The density of the susceptor upper plate 37 is 0.1 to 0.35 g / cm ³ than the density of the susceptor lower plate 38. Can be large. This is because, as the density of the material increases, the effect of temperature rise decreases, so that the graphite density of the susceptor upper plate 37 and the susceptor lower plate 38 is different to give a difference in time for the temperature to rise.

That is, the temperature of the susceptor upper plate 38 rises faster than the susceptor upper plate 37 due to the difference in graphite density, and the reaction gas does not rise to the susceptor upper plate 37 due to this temperature difference. Therefore, the reaction of the silicon carbide of the susceptor upper plate 37 can be suppressed, and the silicon droplets generated by this reaction can be reduced.

Therefore, when the difference between the graphite densities of the susceptor upper plate 37 and the susceptor lower plate 38 is less than 0.1 g / cm ³ , the temperature rises almost equally, and thus it is difficult to play a role of suppressing the generation of silicon droplets. In addition, the difference in graphite density is 0.35 g / cm ³ When flying more, the graphite density of the susceptor bottom plate 38 may be relatively low, which may not meet the graphite density required as the susceptor.

When manufacturing the susceptor upper plate 37 to give such a difference in density, the amount of graphite can be produced by more than the susceptor lower plate 38. That is, by varying the amount of graphite included in the same thickness of the susceptor upper plate 37 and the susceptor lower plate 38 may give a difference in density.

The features, structures, effects and the like described in the foregoing embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. In addition, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the present invention. It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments may be modified. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

10: chamber
20: thermal insulation unit
30: susceptor
37: susceptor top
33: protrusion
38: lower susceptor
40: wafer holder
60: heating element

Claims (9)

chamber;
A susceptor provided in the chamber and
A wafer holder positioned at the susceptor,
The susceptor is
Susceptor tops; And
It includes a susceptor lower plate facing the top of the susceptor,
The susceptor top plate comprises a protrusion. The method of claim 1,
The protrusion is formed on the surface of the susceptor upper plate facing the lower susceptor. The method of claim 2,
The protrusion has a width of 0.1 to 1 mm. The method of claim 3,
The protrusion has a thickness of 0.1 to 1 mm. The method of claim 1,
The susceptor top plate and the susceptor bottom plate include graphite. The method of claim 5,
The deposition apparatus of which the density of the susceptor upper plate and the susceptor lower plate is different. The method of claim 6,
And the susceptor top plate has a higher density than the susceptor bottom plate. The method of claim 7, wherein
And a density of the susceptor upper plate is 0.1 to 0.35 g / cm ³ greater than that of the susceptor lower plate. The method of claim 1,
Insulating unit is provided in the chamber,
And the susceptor is located on the thermal insulation unit.

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