KR101046612B1 - Atomic layer deposition apparatus - Google Patents

Abstract

Disclosed is an atomic layer deposition apparatus including a showerhead in a central portion of a susceptor to prevent vortex and stagnation of deposition gas and to prevent mixing and particle generation of source gas. The atomic layer deposition apparatus includes: a process chamber in which a plurality of substrates are accommodated and a deposition process is performed; a susceptor provided in the process chamber and seated in a horizontal direction and rotatably provided; Shower head having a plurality of injection hole groups for injecting a deposition gas for depositing a thin film on the substrate and having a plurality of injection regions for injecting one type of deposition gas onto the substrate, An exhaust line formed along a boundary and formed of a plurality of exhaust hole groups for sucking and exhausting the exhaust gas in the process chamber and a central exhaust block formed at the center of the showerhead to suck and exhaust the exhaust gas from the central portion of the susceptor It is configured to include.

Atomic layer deposition system, ALD, shower head, deposition gas stagnation

Description

Atomic Layer Deposition Apparatus {ATOMIC LAYER DEPOSITION APPARATUS}

The present invention relates to an atomic layer deposition apparatus, and more particularly, an atomic layer capable of preventing particle generation due to vortices and congestion of deposition gas in the central portion of the susceptor, depositing a thin film uniformly, and improving film quality. Provided is a deposition apparatus.

In general, in order to deposit a thin film having a predetermined thickness on a substrate such as a semiconductor substrate or glass, physical vapor deposition (PVD) using physical collision such as sputtering and chemical vapor deposition using chemical reaction thin film manufacturing method using (chemical vapor deposition, CVD) or the like is used.

The chemical vapor deposition method may include atmospheric pressure chemical vapor deposition (APCVD), low pressure chemical vapor deposition (LPCVD), plasma organic chemical vapor deposition (plasma enhanced CVD, PECVD), and the like. Plasma organic chemical vapor deposition has been widely used due to the advantages of being able to deposit and fast forming thin films.

However, as the design rule of the semiconductor device is drastically fined, a thin film of a fine pattern is required, and the step height of the region where the thin film is formed is also very large. As a result, the use of an atomic layer deposition (ALD) method capable of forming a very fine pattern of atomic layer thickness very uniformly and having excellent step coverage is increasing.

The atomic layer deposition method (ALD) is similar to the conventional chemical vapor deposition method in that it uses chemical reactions between gas molecules. However, unlike conventional chemical vapor deposition (CVD) methods injecting multiple gas molecules into the process chamber at the same time to deposit a reaction product generated above the substrate on the substrate, the atomic layer deposition method includes one source material. Source gas is injected into the process chamber and then purged to physically adsorb the source gas on top of the heated substrate, and then source gas is chemically reacted only on the upper surface of the substrate by injecting a source gas containing another source material. It is different in that it deposits a chemical reaction product. The thin film implemented through such an atomic layer deposition method has a very good step coverage characteristics and has the advantage that it is possible to implement a pure thin film with a low impurity content, which is widely attracting attention.

In general, in the atomic layer deposition apparatus, a deposition gas composed of different kinds of source gases is injected while the shower head or susceptor rotates at high speed, and a thin film is formed on the surface of the substrate while the substrate sequentially passes through the deposition gas. In addition, in the conventional atomic layer deposition apparatus, a substrate is loaded into a process chamber and loaded into a susceptor, a thin film is formed while rotating at a high speed while the susceptor is raised at a predetermined height, and then the susceptor is returned to the loading position when the deposition process is completed. Strong to unload the substrate.

Meanwhile, in the conventional atomic layer deposition apparatus, the exhaust gas including the deposition gas and the unreacted deposition gas injected from the upper part of the susceptor flows into the center of the susceptor due to the high speed rotation of the susceptor, causing vortices to occur. There was a problem that the gas is stagnant in the central portion.

Here, since the source gas is included in the deposition gas and the exhaust gas, when vortices and stagnation occur in the central portion of the susceptor, particles may be generated due to by-products of chemical reactions generated when the gases are mixed with each other. These particles deteriorate the quality of the thin film and cause defects. In addition, when the deposition gas flows into the center of the susceptor, the density of the deposition gas increases in the center portion of the susceptor compared to the edge portion, so that the thin film deposited near the center of the susceptor on the substrate is formed. There is a problem that the thickness is relatively thicker than other parts and the quality and thickness uniformity of the thin film are deteriorated.

Conventionally, an exhaust line may be provided in the central portion of the showerhead to discharge the stagnant exhaust gas of the susceptor. The exhaust line may not exhaust enough of the stagnant exhaust gas of the susceptor center portion. There is a problem of further intensifying the phenomenon that gas is introduced into the center of the susceptor. In addition, when the suction force of the exhaust line provided in the showerhead is increased, since the deposition gas injected from the showerhead may be sucked into the exhaust line before reaching the substrate, the suction force that may act on the exhaust line is substantially limited and thus There is a problem that it is difficult to discharge the stagnant exhaust gas to the susceptor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and to provide an atomic layer deposition apparatus capable of preventing the vortex and stagnation of exhaust gas from occurring at the center portion of the susceptor due to the high speed rotation of the susceptor.

In addition, the present invention is to provide an atomic layer deposition apparatus capable of preventing particle generation and exhaust failure by exhausting the exhaust gas of the susceptor center portion by the exhaust line provided in the shower head.

According to embodiments of the present invention for achieving the above object of the present invention, having a showerhead in the central portion of the susceptor to prevent vortex and stagnation of the deposition gas and to prevent the mixing and particle generation of the source gas The atomic layer deposition apparatus includes: a process chamber in which a plurality of substrates are accommodated and a deposition process is performed; a susceptor provided in the process chamber and seated in a horizontal direction and rotatably provided; Shower head having a plurality of injection hole groups for injecting a deposition gas for depositing a thin film on the substrate and having a plurality of injection regions for injecting one type of deposition gas onto the substrate, A plurality of exhaust hole groups are provided along the boundary to suck and exhaust the exhaust gas in the process chamber. Luer binary is configured to include a central exhaust block formed at the central portion of the shower head and the exhaust line to the discharge by sucking the exhaust gas from the susceptor center.

The injection zone includes at least one source region into which source gas is injected and at least one purge region into which purge gas is injected, and the exhaust line discharges exhaust gas sucked from each source region through different exhaust buffers. It comprises two or more exhaust blocks formed. Here, the exhaust block is formed such that exhaust gas sucked from one source region and the purge region is discharged through one exhaust buffer.

The central exhaust block may be formed such that a center buffer, which is a flow path for discharging exhaust gas sucked from the central exhaust block, is continuously or separated from the exhaust buffer of the exhaust block. In addition, the central exhaust block may be formed to have a region having a size corresponding to the central portion of the susceptor. In addition, the central exhaust block may be formed to discharge the exhaust gas sucked from each source region through different center buffers.

The exhaust line may include an auxiliary exhaust block formed to cross the injection area. For example, the auxiliary exhaust block may be formed such that an auxiliary buffer, which is a flow path for discharging exhaust gas sucked from the auxiliary exhaust block, is in communication with or separated from the exhaust block and the central exhaust block.

As described above, according to the present invention, first, by increasing the width and width of the exhaust line of the central portion of the showerhead to increase the area acting the suction force in the exhaust line to increase the displacement, in particular, the susceptor center Since the exhaust gas suction amount of the portion is increased, it is possible to prevent the vortex and stagnation of the exhaust gas from occurring in the center portion of the susceptor.

Second, it is possible to deposit a thin film of uniform thickness on the substrate and improve the quality of the thin film by preventing particle generation due to the mixing of exhaust gas in the center of the susceptor and eliminating the increase in gas density in the center of the susceptor.

Third, the injection zones are adjacent to each other at the central portion of the shower head, and by forming a central exhaust block, it is possible to effectively prevent the mixing of different source gases through the central portion of the shower head.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited or limited by the embodiments. In describing the present invention, a detailed description of well-known functions or constructions may be omitted for clarity of the present invention.

Hereinafter, an atomic layer deposition apparatus 100 according to embodiments of the present invention will be described in detail with reference to FIGS. 1 to 6. For reference, FIG. 1 is a perspective view of an atomic layer deposition apparatus 100 according to an embodiment of the present invention, and FIG. 2 illustrates an example of the showerhead 103 in the atomic layer deposition apparatus 100 of FIG. 1. 3 is a cross-sectional view of the showerhead 103 taken along line II of FIG. 2. FIG. 4 is a plan view illustrating a modification example of the showerhead 103 of FIG. 2, FIG. 5 is a cross-sectional view taken along line II-II of the showerhead 103 of FIG. 4, and FIG. 6 is III in FIG. 4. It is sectional drawing along the -III line.

Referring to FIG. 1, the atomic layer deposition apparatus 100 includes a process chamber 101, a susceptor 102, a showerhead 103, and an exhaust unit 104.

The process chamber 101 accommodates the substrate 10 and provides a space for depositing a predetermined thin film on the surface of the substrate 10. Here, since the deposition process is performed in a low pressure atmosphere close to the vacuum, the atomic layer deposition apparatus 100 has a hermetic structure capable of maintaining a vacuum.

The substrate 10 may be a silicon wafer. However, the object of the present invention is not limited to the silicon wafer, and the substrate 10 may be a transparent substrate including glass used for a flat panel display device such as a liquid crystal display (LCD) and a plasma display panel (PDP). have. In addition, the substrate 10 is not limited in shape and size by the drawings, and may have substantially various shapes and sizes, such as a circle and a rectangle.

The susceptor 102 is provided in the process chamber 101 to allow the plurality of substrates 10 to be seated in a horizontal direction and to orbit the substrate 10 with respect to the center of the susceptor 102. The rotating shaft 125 is provided. As the susceptor 102 rotates, a predetermined thin film is formed on the surface of the substrate 10 while the substrate 10 sequentially passes through the deposition gas. For example, the susceptor 102 has a flat plate shape having a flat top surface and a predetermined diameter so that the substrate 10 may be horizontally seated, and the plurality of substrates 10 may have the susceptor ( Along the circumferential direction of 102).

Here, the shape of the susceptor 102 is not limited to a circular shape and may have various shapes, and the number of substrates 10 mounted on the susceptor 102 may also be changed.

The shower head 103 is provided above the process chamber 101 to provide the deposition gas to the surface of the substrate 10 seated on the susceptor 102.

The deposition gas is a gas used in a process of depositing a thin film, at least one source gas, a source gas and the substrate 10 including a source material constituting a thin film to be deposited on the substrate 10, A stable gas that does not react chemically with the deposited thin film is used for purging the source gas. For example, the deposition gas is composed of two different source gases (hereinafter, referred to as first gas S1 and second gas S2) and one type of purge gas PG.

The shower head 103 is formed with a plurality of injection holes 131 for the injection of the deposition gas and an injection buffer 132 that is a flow path for supplying the deposition gas to the injection hole 131, the injection buffer One side is provided with a gas supply unit 105 for supplying the deposition gas to the injection buffer 132. For example, the gas supply unit 105 may include a first supply source 151 supplying the first gas S1, a second supply source 152 supplying the second gas S2, and the purge gas PG. ) May be configured as a third source 153 for supplying ().

In addition, the shower head 103 is provided with an exhaust portion 104 for sucking and exhausting the exhaust gas in the process chamber 101, the exhaust portion 104 is the exhaust gas inside the process chamber 101 It consists of an exhaust line 140 consisting of a plurality of exhaust holes 141 for sucking the exhaust buffer 142 (see Fig. 3) which is a flow path of the exhaust gas sucked from the exhaust hole 141.

The shower head 103 is formed with a spraying region 130 defined by a plurality of spraying hole groups 131 in which one type of deposition gas is sprayed onto the substrate 10. According to the number of deposition gases, a plurality of injection regions 130 are formed. For example, the injection region 130 may include a first source region 311, a second source region 313, and the first source through which the first gas S1 and the second gas S2 are injected, respectively. It is divided into two purge regions 312 and 314 disposed adjacent to the region 311 and the second source region 313 to which the purge gas PG is injected. As shown by a dotted line in FIG. 2, the spraying region 130 is formed in a fan shape roughly dividing the shower head 103.

The size, number, and arrangement of the injection holes 131 are not limited by the drawings, and may be disposed in substantially various forms to uniformly inject the deposition gas into the substrate 10. In addition, the injection hole 131 may have a circular hole or a slit shape. Likewise, the size, size, number and arrangement of the exhaust holes 141 are not limited by the drawings and may be changed in various ways.

The exhaust line 140 is defined as a plurality of exhaust hole 141 groups formed along the boundary of the injection area 130. That is, the exhaust line 140 serves to partition the discharge area of the exhaust gas and the injection region 130. For example, the exhaust line 140 is provided along the boundary of each spraying region 130 to form two 'U' or 'c' shapes to partition the shower head 103 into approximately four regions. Exhaust blocks 411 and 412 are provided, and in particular, the exhaust blocks 411 and 412 are formed to be adjacent to each other at a predetermined length at the center of the shower head 103. Hereinafter, a portion in which the exhaust blocks 411 and 412 are formed adjacent to each other in the central portion of the shower head 103 is called a central exhaust block 415 and is illustrated by a dotted box in FIG. 2.

Here, the central exhaust block 415 is defined as a portion formed in the central portion of the shower head 103 among the exhaust blocks 411 and 412, and may be continuously formed with the exhaust blocks 411 and 412. However, unlike the above-described embodiment, the central exhaust block 415 may be formed to have exhaust buffers 142a, 142 (see FIG. 3) independent of the exhaust blocks 411, 412. Here, the exhaust block 411 and 412 and the central exhaust block 415 are formed continuously, the buffer and the central exhaust block 415 to discharge the exhaust gas sucked in the exhaust block (411, 412) This means that the buffer through which exhaust gas sucked in is discharged is formed in communication. In addition, as illustrated in FIGS. 2 and 4, the exhaust blocks 411 and 412 and the central exhaust block 415 include a continuous shape.

On the other hand, since the unreacted source material is included in the exhaust gas, the exhaust gas sucked in the first source region 311 and the second source region 313 is the exhaust buffer 142 or the exhaust unit 104. ) Particles can be generated by reacting with each other inside. Therefore, the first and second source regions 311 and 313 should be formed to discharge the exhaust gas through the exhaust blocks 411 and 412 having flow paths that are independent of each other. However, since the purge gas PG does not chemically react with the first and second gases S1 and S2, in the purge regions 312 and 314, the first source region 311 or the second source region ( Exhaust gases may be exhausted using the same exhaust blocks 411 and 412 as 313. In the present exemplary embodiment, the exhaust line 140 may include a first exhaust block 411 and a second source region formed to suck exhaust gas from the first source region 311 and the purge regions 312 and 314. 313 and the second exhaust block 412 formed to suck the exhaust gas from the purge regions 312 and 314.

In addition, the central exhaust block 415 also has an exhaust buffer inside the central exhaust block 415 so that the exhaust gases sucked from the first source region 311 and the second source region 313 are not mixed with each other. Compartments can be formed.

Here, the first source region 311 and the second source region 313 are adjacent to each other in the central portion of the shower head 103 due to the morphological characteristics of the spraying region 130 and the shower head 103. Done. However, according to the present exemplary embodiment, the central exhaust block 415 is formed at the center of the shower head 103, so that the center and the first and second source regions 311 and 313 at the center of the shower head 103 are formed. Inflow and mixing of the first and second gases S1 and S2 may be prevented.

1 and 1, when the susceptor 102 rotates at a high speed, the exhaust gas on the susceptor 102 is the central portion CA of the susceptor 102. In the process of inflow to the vortex of the exhaust gas and congestion due to this occurs. Here, the central portion CA is defined as a region in which the vortices are generated while the exhaust gas is introduced near the center of the susceptor 102, and the substrate 10 is seated on the susceptor 102. It is not an area.

The central exhaust block 415 increases the exhaust volume of the central portion CA of the susceptor 102 in which the vortices and stagnation of the exhaust gas occur in this way, thereby vortexing and stagnating the exhaust gas in the central portion CA. To prevent it from happening.

In detail, the central exhaust block 415 forms a plurality of exhaust holes 141 in the central portion of the shower head 103, which is a portion corresponding to the central portion CA of the susceptor 102. Increase the displacement of the portion CA. That is, the exhaust line 140 has a shape in which two exhaust blocks 411 and 412 provided along the boundary of the injection region 130 are adjacent to each other at the center of the shower head 103. In addition, the central exhaust block 415 is formed such that the exhaust hole 141 may be disposed in the entire region corresponding to the central portion CA. For example, as illustrated in FIGS. 2 and 3, the central exhaust block 415 is formed in a straight shape having a predetermined length at the center of the shower head 103. In addition, the central exhaust block 415 may have an expanded shape than the exhaust blocks 411 and 412 so as to correspond to the size of the central portion CA.

However, the present invention is not limited by the drawings, and the shape and location of the exhaust line 140, the exhaust blocks 411 and 412, and the central exhaust block 415 may be changed in various ways.

Meanwhile, in order to increase the displacement of the exhaust line 140, the area of the exhaust blocks 411 and 412 and the number of the exhaust holes 141 may be increased.

4 to 6 illustrate an example of the shower head 103 in which the area of the exhaust blocks 411 and 412 is increased as a modified embodiment of the above-described embodiment. The embodiments described below are substantially the same except for the above-described embodiment and the shape of the exhaust blocks 411 and 412, and the same names and reference numerals are used for the same components, and redundant descriptions are omitted. do.

Referring to the drawings, the exhaust line 140 is formed at the center of the exhaust block 411 and 412 and the shower head 103 formed along the boundary of the injection region 130 to form a central portion of the susceptor 102. And a central exhaust block 416 for sucking and discharging the exhaust gas of CA.

The exhaust line 140 includes two exhaust blocks 411 and 412 having a 'U' or 'c' shape for dividing the shower head 103 into approximately four areas, and the diameter of the shower head 103. Two auxiliary exhaust blocks 413 and 414 formed to cross the shower head 103 in a direction may be formed.

The exhaust blocks 411 and 412 are formed with two exhaust blocks 411 and 412 to prevent mixing of the exhaust gas sucked in the first source region 311 and the second source region 313. do.

The auxiliary exhaust blocks 413 and 414 are formed to cross the purge regions 312 and 314. In this case, when the injection pressure of the purge gas PG is high, the thickness of the film deposited on the substrate 10 may be unevenly formed while the first and second gases S1 and S2 are biased in one direction. . The auxiliary exhaust blocks 413 and 414 are formed in the purge regions 312 and 314 to control the injection pressure of the purge gas PG.

In FIG. 4, reference numerals 313a, 313b, 314a, and 314b denote regions in which the purge regions 313 and 314 are defined by the auxiliary exhaust blocks 413 and 414, respectively.

The exhaust blocks 411 and 412 and the auxiliary exhaust blocks 413 and 414 may be formed continuously or independently of each other. However, both the exhaust blocks 411 and 412 and the auxiliary exhaust blocks 413 and 414 may prevent the exhaust gas sucked from the first source region 311 and the second source region 313 from mixing. So that it is formed.

The exhaust hole 141 is densely arranged in the central portion of the shower head 103 to form a central exhaust block 416 for sucking the exhaust gas of the central portion CA of the susceptor 102. The central exhaust block 416 may be formed in communication with the exhaust blocks 411 and 412 and the auxiliary exhaust blocks 413 and 414 or may be formed independently of each other. However, the central exhaust block 416 may include two or more central exhaust blocks 416 to prevent mixing of the exhaust gases sucked in the first source region 311 and the second source region 313. As shown in FIG. 6, the two central exhaust blocks 416 may be formed with independent exhaust buffers 142a and 142b which form independent flow paths.

As described above, the present invention has been described with reference to the preferred embodiments, but those skilled in the art can variously modify the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated that it can be changed.

1 is a perspective view of an atomic layer deposition apparatus according to an embodiment of the present invention;

FIG. 2 is a plan view illustrating an example of a showerhead in the atomic layer deposition apparatus of FIG. 1; FIG.

3 is a cross-sectional view taken along line II of the showerhead of FIG. 2;

4 is a plan view for explaining another example of the showerhead of FIG. 2;

5 is a cross-sectional view taken along the line II-II of the showerhead of FIG. 4;

6 is a cross-sectional view taken along line III-III of the showerhead of FIG. 4.

<Explanation of symbols for the main parts of the drawings>

10: substrate 100: atomic layer deposition apparatus

101: process chamber 102: susceptor

103: shower head 104: exhaust

105: gas supply unit 125: rotating shaft

130: injection area 131: injection hole

132: injection buffer 140: exhaust line

141: exhaust hole 142: exhaust buffer

311, 312: source area

313, 313a, 313b, 314, 314a, 314b: purge region

411, 412: exhaust block 413, 414: auxiliary exhaust block

415, 416: center exhaust block

Claims (8)

A process chamber in which a plurality of substrates are accommodated and a deposition process is performed; A susceptor provided in the process chamber, the susceptor being rotatably seated in the horizontal direction; It is formed on the susceptor is composed of a plurality of injection hole groups for injecting a deposition gas for depositing a thin film on the substrate, consisting of one or more source region to which the source gas is injected and one or more purge region is injected into the purge gas A shower head having a plurality of spray regions; A plurality of exhaust hole groups are provided along the boundary of each injection area in the shower head and suck and discharge the exhaust gas in the process chamber, and the exhaust gas sucked in each source area is discharged through different exhaust buffers. An exhaust line comprising two or more exhaust blocks configured to exhaust; And A central exhaust block formed in a central portion of the shower head to suck and exhaust exhaust gas from the central portion of the susceptor; Including, And each exhaust block is configured such that exhaust gas sucked from one source region and the purge region is discharged through one exhaust buffer. delete delete The method of claim 1, The central exhaust block, And a central buffer, which is a flow path for discharging the exhaust gas sucked from the central exhaust block, continuously or separately from the exhaust buffer of the exhaust block. 5. The method of claim 4, And the central exhaust block is formed to have a region having a size corresponding to a central portion of the susceptor. 5. The method of claim 4, And the central exhaust block is configured to discharge exhaust gas sucked from each source region through different center buffers. The method of claim 1, The exhaust line further comprises an auxiliary exhaust block formed to cross the injection area. The method of claim 7, wherein The auxiliary exhaust block is an atomic layer deposition apparatus, characterized in that the auxiliary buffer which is a flow path for discharging the exhaust gas sucked in the auxiliary exhaust block is formed so as to communicate with or separate from the exhaust block and the central exhaust block.

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