KR20210001183A - Source material supply and film forming apparatus - Google Patents

Abstract

According to an embodiment of the present invention, provided is a raw material supply unit which can improve film forming speed. The raw material supply unit comprises: a liner which can accommodate a raw material; a crucible having a liner seating space for the liner to be seated; and a main heater heating and evaporating the raw material by heating the crucible, wherein the crucible and the liner each have an open top surface, and an evaporation hole is formed on a side surface of the liner. As the raw material is evaporated not only at the top but also through the evaporation hole, the raw material can be ejected to the top of the crucible.

Description

Raw material supply unit and film forming apparatus including the same {SOURCE MATERIAL SUPPLY AND FILM FORMING APPARATUS}

The following description relates to a raw material supply unit and a film forming apparatus including the same.

The film forming apparatus is an apparatus for forming a film on a film-forming object such as a substrate, a sensor, or a display using a specific raw material, and the film-forming apparatus may be configured in various ways depending on the raw material. For example, there is a method of forming a film on a film-forming object using a raw material evaporated by applying heat to a raw material, or forming a film on the film-forming object through a sputtering method in which plasma is generated to collide with the raw material.

The above-described background technology is possessed or acquired by the inventor in the process of deriving the present invention, and is not necessarily a known technology disclosed to the general public prior to filing the present invention.

An object of an embodiment is to provide a raw material supply unit capable of preventing deterioration of supplied raw materials and improving a film formation speed, and a film forming apparatus including the same.

According to an embodiment, the raw material supply unit includes a liner capable of receiving raw materials; A crucible having a liner seating space for seating the liner; And a main heater for heating and evaporating the raw material by heating the crucible, wherein the crucible and the liner each have an open top surface, and an evaporation hole is formed on a side surface of the liner, By evaporating the raw material not only through the upper part but also through the evaporation hole, it may be ejected to the upper part of the crucible.

The longitudinal central axis of the crucible coincides with the longitudinal central axis of the liner, and the inner diameter of the crucible is formed larger than the outer diameter of the liner, so that a donut-shaped gap is formed between the crucible and the liner, and the inside of the liner The raw material evaporated through the evaporation hole may be communicated with the upper portion of the liner through the donut-shaped gap.

The thickness of the donut-shaped gap may be 0.5mm to 2.0mm.

The cross-sectional area of the donut-shaped gap may be 90% to 110% of the sum of the areas of the evaporation holes.

The raw material supply unit may further include a support protrusion formed in at least one of the crucible and the liner to prevent the liner from shaking inside the crucible.

The support protrusion may have a shape in which a cross-sectional area becomes narrower toward a direction in which the liner is inserted toward the crucible.

The raw material supply unit further includes an auxiliary heater disposed at a position spaced upward from the auxiliary heater, and the main heater is located above the crucible to prevent the evaporated raw material from sticking to the upper side of the crucible can do.

The main heater may be driven at a temperature higher than that of the auxiliary heater.

The thermal conductivity of the liner may be lower than the thermal conductivity of the crucible.

The material of the crucible is any one of graphite and pyrolytic boron nitride (PBN), and the material of the liner is titanium (Ti), tantalum (Ta), stainless steel (SUS), and oxidation. It may be any one of aluminum (Al ₂ O ₃ ).

The liner may include an outer partition wall surrounding a receiving portion for receiving the raw material therein; And an inner partition wall enclosing a cavity in which the raw material is not accommodated therein, and partitioning between the receiving portion and the cavity, wherein the evaporation hole is formed on a side surface of the outer partition wall, and from the receiving portion A first evaporation hole serving as a passage through which the raw material is evaporated through the partition wall; And a second evaporation hole formed on a side surface of the inner partition wall and serving as a passage through which the raw material is evaporated from the receiving portion through the inner partition wall.

The evaporation hole may be formed only on the lower side of the side surface of the liner.

The area in which the evaporation hole is formed may be within 25% of the total length of the liner from the lower end of the liner.

The raw material supply unit may further include a nozzle cap positioned above the liner, and a nozzle hole having an area smaller than an upper surface open area of the liner may be formed in the center of the nozzle cap.

The raw material supply unit further includes an intermediate cap positioned between the nozzle cap and the liner, wherein the intermediate cap includes: a plurality of intermediate holes disposed radially at a predetermined angle; And an interference part positioned at the center of the plurality of intermediate holes and overlapping with the nozzle hole in a direction perpendicular to the ground.

The sum of the areas of the plurality of intermediate holes may be smaller than the areas of the nozzle holes.

The crucible has a larger diameter than the liner seating space, and further includes a cap seating space formed on an upper side of the liner seating space, and in a state where the liner is seated in the liner seating space, the intermediate cap and the The nozzle cap may be sequentially seated and positioned in the cap seating space.

The inner diameter of the intermediate cap may be the same as the inner diameter of the liner seating space.

The raw material supply unit may further include a main heater disposed at a position overlapping the nozzle cap and the intermediate cap when viewed from the side.

According to an embodiment, a film forming apparatus includes a liner having at least a part of a side surface and an open upper surface, a crucible having an open upper surface and accommodating the liner, and a main heater for heating and evaporating the raw material contained in the liner. A raw material supply unit; And a controller for controlling a driving temperature of the main heater based on the evaporation rate of the raw material.

The raw material supply unit further includes an auxiliary heater disposed at a position spaced downward from the main heater, and the main heater is located above the crucible to prevent the evaporated raw material from sticking to the upper side of the crucible In addition, the controller may independently control a driving temperature of the auxiliary heater and a driving temperature of the main heater.

According to an embodiment, while the film forming apparatus is operated at a low temperature, it is possible to reduce a phenomenon in which raw materials are decomposed and deteriorated by heat, so that even if raw materials that are more vulnerable to heat are used compared to conventional raw materials, film formation can be performed stably. have.

1 is a diagram illustrating a film forming apparatus according to an exemplary embodiment.
2 is a cross-sectional view of a raw material supply unit according to an exemplary embodiment.
3 is an exploded cross-sectional view of a raw material supply unit according to an embodiment.
4 is a perspective view illustrating a nozzle cap and an interference cap according to an exemplary embodiment.
5 and 6 are diagrams illustrating a state in which a raw material gas flows inside a raw material supply unit according to an exemplary embodiment.
7 is a cross-sectional view of a raw material supply unit according to another embodiment.
8 is a top view of a raw material supply unit shown in FIG. 7.
9 is a cross-sectional view of a raw material supply unit according to another embodiment.

Hereinafter, embodiments will be described in detail through exemplary drawings. In adding reference numerals to elements of each drawing, it should be noted that the same elements are assigned the same numerals as possible even if they are indicated on different drawings. In addition, in describing the embodiment, if it is determined that a detailed description of a related known configuration or function interferes with the understanding of the embodiment, a detailed description thereof will be omitted.

In addition, in describing the constituent elements of the embodiment, terms such as first, second, A, B, (a) and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, order, or order of the component is not limited by the term. When a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected or connected to that other component, but another component between each component It should be understood that may be “connected”, “coupled” or “connected”.

Components included in one embodiment and components including common functions will be described using the same name in other embodiments. Unless otherwise stated, descriptions in one embodiment may be applied to other embodiments, and detailed descriptions in the overlapping range will be omitted.

1 is a diagram showing a film forming apparatus according to an embodiment, FIG. 2 is a cross-sectional view of a raw material supply unit according to an embodiment, Fig. 3 is an exploded cross-sectional view of a raw material supply unit according to an embodiment, and FIG. 4 is an embodiment It is a perspective view showing the nozzle cap and the interference cap according to.

1 to 4, the film forming apparatus 1 according to an exemplary embodiment uses the raw material S accommodated in the raw material supply unit 2 to form a film on the surface of a film-forming object such as a substrate B. It is a device that can. The film forming apparatus 1 may include at least one raw material supply unit 2, a rotating plate R for rotating the raw material supply unit 2, and a control unit C capable of controlling them.

The raw material supply unit 2 can supply a material for a film to be formed on the object to be formed by evaporating the raw material S contained therein. Here, "evaporation" means that (i) the raw material (S) is melted into a liquid state and then vaporized into a gaseous state, as well as (ii) the raw material (S) is directly in a solid state. It should be noted that it is a concept that includes sublimation into a gaseous state. The raw material S may be, for example, an organic material. In the case of organic materials, in particular, since the heat transfer property is not good, the raw material located closer to the inner wall of the crucible 21 is more likely to evaporate faster than the center of the crucible 21 (see FIG. 6 ). In consideration of this tendency, the raw material supply unit 2, the crucible 21 and/or the liner 22 have a shape having a length (or height) longer than a diameter (or width), and a raw material supply unit having such a shape ( By arranging a plurality of 2), it is possible to provide a more uniform evaporation amount than when using a raw material supply unit having one large diameter. The raw material supply unit 2 may include a crucible 21, a liner 22, a main heater 27, an auxiliary heater 23, a nozzle cap 25, and an intermediate cap 26.

The crucible 21 may have an upper surface open toward the object to be deposited and accommodate the liner 22. Heat transferred to the crucible 21 through the auxiliary heater 23 may be transferred to the raw material S through the liner 22. The crucible 21 may include a liner seating space 212, a cap seating space 213, and a support protrusion 214.

The liner seating space 212 is a space in which the liner 22 is seated, and has a diameter larger than the outer diameter of the liner 22, and thus a donut-shaped gap g between the liner seating space 212 and the liner 22 Can be formed.

The cap seating space 213 may have a larger diameter than the liner seating space 212 and may be formed on the upper side of the liner seating space 212. According to such a structure, since a stepped shape is formed from the cap seating space 213 to the liner seating space 212, in a state where the liner 22 is seated in the liner seating space 212, the cap seating space 213 As a result, the intermediate cap 26 and the nozzle cap 25 may be sequentially seated and positioned.

The support protrusion 214 may protrude inwardly from an inner wall forming the liner seating space 212, and may support the side surface of the liner 22. For example, the support protrusion 214 is formed at three or more points as shown in FIG. 8, so that the liner 22 may be prevented from shaking inside the crucible 21. As shown in Fig. 8, when viewed from the top, the support protrusion 314 reduces obstruction of the flow of the raw material S evaporated through the donut-shaped gap g, and the uniformity of the flow of the raw material S It may be formed to be spaced apart at a radially constant angle so as not to impede. The support protrusion 214 may have a shape in which a cross-sectional area becomes narrower as the liner 22 is inserted toward the crucible 21. For example, the support protrusion 214 includes an inclined portion inclined downward toward the center of the crucible 21, so that the liner 22 may be easily inserted into the crucible 21.

On the other hand, the support protrusion 214 has been exemplarily described with respect to the embodiment formed on the crucible 21, but, unlike this, those of ordinary skill in the art will understand that the support protrusion 214 may be formed on the liner 22 I will be able to. In addition, it is also possible that the support protrusion 214 is formed in both the crucible 21 and the liner 22. For example, the support protrusion 214 may protrude outward from the outer wall of the liner 22 to support the inner wall of the liner seating space 212 of the crucible 21. In this case, the support protrusion 214 includes an inclined portion that is inclined upward in a direction away from the center of the crucible 21, so that the liner 22 can be easily inserted into the crucible 21.

The liner 22 is a part that directly receives the raw material S and serves as a medium for transferring the heat received from the crucible 21 to the raw material S. The thermal conductivity of the liner 22 may be lower than that of the crucible 21. For example, the material of the crucible 21 is any one of graphite and pyrolytic boron nitride (PBN), and the material of the liner 22 is titanium (Ti), tantalum (Ta) , Stainless steel (SUS), aluminum oxide (Al ₂ O ₃ ) It may be any one of. According to this configuration, in consideration of the physical properties of the raw material (S), it is possible to appropriately delay the speed at which the heat transferred through the crucible 21 is transferred to the inside of the liner 22, so that the raw material (S) is more than necessary. Heated to temperature can reduce the problem of deterioration. In addition, as the heat transferred to the inside of the liner 22 is delayed, the temperature of the donut-shaped gap g between the crucible 21 and the liner 22 can be kept sufficiently high, so that the donut having a fairly narrow gap It is possible to reduce the problem that the donut-shaped gap g is closed by depositing the raw material S in the mold gap g.

The liner 22 may have a shape in which at least a portion of a side surface and an upper surface thereof are open. The liner 22 may include an evaporation hole 221 formed on a side surface and a receiving portion 222 formed therein to receive the raw material S.

The evaporation hole 221 may allow the raw material S to be evaporated from the inside of the liner 22 to communicate with the upper portion of the liner 22 through a donut-shaped gap g. Therefore, the raw material S accommodated in the receiving portion 222 may evaporate not only through the upper surface of the liner 22 having a limited area, but also through the side surface of the liner 22 and be ejected to the top of the crucible 21 , The film forming speed of the film forming apparatus 1 can be dramatically improved.

On the other hand, since the lower portion of the liner 22 has a closed structure, it is possible to prevent the raw material S from directly contacting the crucible 21. For example, the evaporation hole 221 may not be formed on the lower surface of the liner 22. According to such a structure, by preventing the raw material from directly contacting the crucible 21 having high thermal conductivity or transferring heat from the crucible 21 directly to the centrally located raw material S, the raw material S Can reduce the problem of deterioration.

As disclosed in FIG. 2 and the like, the crucible 21 and the liner 22 may each have an open top surface. In other words, the crucible 21 and the liner 22 may both be opened in the same direction. According to this structure, since the evaporated raw material S rises in the evaporating direction as it is and can approach perpendicularly to the surface of the object to be formed, fast film formation can be performed.

The center axis in the longitudinal direction of the crucible 21 coincides with the center axis in the longitudinal direction of the liner 22, and the inner diameter of the crucible 21 is formed larger than the outer diameter of the liner 22, so that the crucible 21 and the liner 22 A donut-shaped gap g having a uniform thickness may be formed between ).

For example, the thickness of the donut-shaped gap g may be 0.5mm to 2.0mm. If the thickness of the donut-shaped gap g is less than 0.5 mm, the raw material S is fixed to the donut-shaped gap g, thereby causing a problem of blocking the flow path through the donut-shaped gap g. When the thickness of the doughnut-shaped gap g is greater than 2.0 mm, the conductivity of heat provided from the crucible 21 toward the liner 22 is rapidly decreased. In addition, when the thickness of the doughnut-shaped gap g is greater than 2.0 mm, the raw material evaporated through the top of the liner 22 is higher than the level at which the evaporation amount of the raw material S evaporated to the side through the evaporation hole 221 increases. The level at which the evaporation amount of S) decreases increases. Accordingly, the thickness of the donut-shaped gap g can be designed within the above-described range.

The cross-sectional area of the donut-shaped gap g may be 90% to 110% of the sum of the areas of the evaporation holes 221. If the cross-sectional area of the donut-shaped gap (g) is less than 90% of the sum of the area of the evaporation hole (221), a differential pressure is applied by the raw material (S) gas stagnating between the inlet and outlet ends of the donut-shaped gap (g). As a result, the pressure in the doughnut-shaped gap g increases, thereby preventing evaporation through the evaporation hole 221. In addition, there may be a problem that the raw material S contained in the stagnant gas phase is decomposed. In addition, the velocity of the raw material (S) gas discharged through the donut-shaped gap (g) is different from each other, the speed of the raw material (S) gas discharged through the upper portion of the liner 22, it is possible to hinder the uniformity of film formation. . When the cross-sectional area of the doughnut-shaped gap g exceeds 110%, the conductivity of heat provided from the crucible 21 toward the liner 22 decreases, resulting in a negative effect such as a decrease in process efficiency.

The main heater 27 can evaporate the raw material S contained in the liner 22 by heating the crucible 21. For example, the main heater 27 may have a shape surrounding the outer periphery of the crucible 21.

For example, the main heater 27 is disposed above the crucible 21 to prevent the raw material S evaporated from the liner 22 from sticking to the upper side of the crucible 21. For example, the main heater 27 is disposed at a position overlapping the nozzle cap 25 and the intermediate cap 26 when viewed from the side, so that the raw material on the inner walls of the nozzle cap 25 and the intermediate cap 26 (S) can prevent the problem of sticking.

The auxiliary heater 23 can evaporate the raw material S contained in the liner 22 by heating the crucible 21. For example, the auxiliary heater 23 may have a shape surrounding the outer periphery of the crucible 21. For example, the auxiliary heater 23 may be disposed at a position spaced downward from the main heater 27. According to such a structure, the crucible 21 and the liner 22 are formed long in the longitudinal direction, so that even if the raw material S is located at a portion far from the main heater 27, the main heater 27 and/or auxiliary By appropriately controlling the heater 23, it is possible to perform temperature control for each section of the raw material S. If necessary, a plurality of auxiliary heaters 23 may be spaced apart.

The nozzle cap 25 may be positioned above the liner 22. In the center of the nozzle cap 25, a nozzle hole 251 having an area smaller than the top open area of the liner 22 may be formed. According to the nozzle hole 251, it is possible to improve the uniformity of film formation compared to the case of performing film formation in a state where the top surface of the liner 22 is completely open without the nozzle cap 25, and in particular, the film according to the remaining amount of raw materials. It can reduce the change of thickness over time. The nozzle hole 251 is formed in the center of the nozzle cap 25, and the peripheral portion of the nozzle hole 251 can shield the upper side of the edge portion of the liner 22. As disclosed in FIG. 6 to be described later, the raw material S exhibits a higher evaporation amount at a portion close to the inner wall side of the crucible 21, that is, at the edge portion of the liner 22. In a direction perpendicular to the ground, the nozzle cap 25 shields the rim of the liner 22 so that the raw material S evaporated from the rim of the liner 22 is ejected vertically to the upper side of the crucible 21. Can be prevented. Accordingly, the nozzle cap 25 prevents the raw material S that rapidly evaporates from the edge portion of the liner 22 from being directly transferred to the film-forming object, and the nozzle space 252 formed inside the nozzle cap 25 In, by sufficiently mixing, the uniformity of film formation can be improved. In consideration of such a function, the nozzle space 252 may be referred to as a “mixing space”.

The intermediate cap 26 may be positioned between the nozzle cap 25 and the liner 22. For example, as shown in FIG. 2, the inner diameter of the intermediate cap 26 may be the same as the inner diameter of the liner seating space 212. According to this structure, since the stepped portion on the flow path through which the raw material S evaporated through the evaporation hole 221 is transferred to the intermediate cap 26 can be removed, the raw material S gas is fixed in the flow path. You can avoid the problem. In the intermediate space 262 formed inside the intermediate cap 26, not only the raw material S evaporated above the liner 22, but also the raw material evaporated to the side of the liner 22 through the evaporation hole 221 ( S) is also introduced and mixed together, so that the uniformity of the raw material S gas provided from the raw material supply unit 2 can be further improved.

As shown in FIG. 4, the intermediate cap 26 includes a plurality of intermediate holes 261 radially arranged at a constant angle, and an interference unit (not sign) located at the center of the plurality of intermediate holes 261 can do. The interference part may overlap the nozzle hole 251 in a direction perpendicular to the ground. For example, the diameter d1 of the nozzle hole 251 (see FIG. 3) may be shorter than the distance d2 between the plurality of intermediate holes 261 (see FIG. 3 ). According to such a structure, the raw material (S) gas ejected through the intermediate hole 261 is in the nozzle space 252, (i) the bottom edge of the nozzle cap 25, and (ii) the intermediate cap ( 26) collides with the interference, and can be mixed more evenly.

As shown in FIG. 4, the sum of the areas of the plurality of intermediate holes 261 may be smaller than the areas of the nozzle holes 251. The intermediate hole 261 may be installed to overlap at a position where the evaporation rate of the raw material S is relatively fast. In other words, when viewed in a direction perpendicular to the ground, the intermediate hole 261 may be located inside rather than the sidewall of the liner 22 and may be formed at a point spaced apart from the center of the liner 22. According to such a structure, a process in which particles of the raw material (S) contained in an irregular distribution in the gas ejected through the side and upper sides of the liner 22 rapidly inflow and pass through the relatively narrow middle hole 261 in a large amount In, the uniformity of the raw material (S) particles in the gas can be improved. In addition, in such a process, in the intermediate space 262 formed inside the intermediate cap 25, the raw material S gases each evaporated at different evaporation rates may be mixed. In other words, the raw material (S) gas evaporated through the evaporation hole 221, the raw material (S) gas evaporated from the rim of the liner 22, and the raw material (S) evaporated from the center portion of the liner 22 The gases can be mixed with each other.

On the other hand, since the raw material S is evaporated from the upper and side surfaces of the liner 22, the raw material S located under the center of the liner 22 accumulates heat for the longest time. A heater may not be provided on the lower side (bottom) of the liner 22 so that the raw material S is not deteriorated by the accumulated heat.

The controller C may control a film-forming object (or a support structure supporting the film-forming object), a raw material supply unit 2, and the like. For example, the controller C may independently control the driving temperature of the main heater 27 and the driving temperature of the auxiliary heater 23. For example, the control unit C causes the main heater 27 to be driven at a temperature higher than the temperature of the auxiliary heater 23, so that the raw material S from the upper side of the crucible 21 in a relatively low temperature state It is cooled before reaching the object to be deposited, thereby preventing the problem of sticking to unwanted surrounding parts.

For example, the control unit C controls the amount of evaporation of the raw material S by controlling the driving temperature of the portion where the raw material S is first evaporated, that is, the main heater 27 located above the crucible 21. can do. In this process, the part where the raw material S is later evaporated, that is, the driving temperature of the auxiliary heater 23 located at the lower side of the crucible 21 is controlled to be lower than the driving temperature of the main heater 27, While preventing excessive heat from being provided to the located raw material S, it is possible to assist in the role of the main heater 27.

On the other hand, when the raw material S evaporates and the height of the raw material S decreases, the control unit C increases the driving temperature of the raw material S by a distance spaced apart from the main heater 27, Evaporation can be maintained. Here, the height of the raw material S is based on various previously measured data, such as (i) the height of the raw material S over time, or (ii) a sensor that directly measures the amount of change in the thickness of the film formed on the object , (iii) It may be collected through a flow meter for measuring the flow rate of the raw material (S) gas ejected from the raw material supply unit (2).

Meanwhile, depending on the type of the raw material S, the difference between the evaporation temperature and the denaturation temperature may not be very large. In other words, when the driving temperature of the main heater 27 increases excessively, there is a concern that the raw material S gas may be deteriorated during the rising process. Accordingly, the control unit C can supplement the amount of heat to be provided to the raw material S by increasing the driving temperature of the auxiliary heater 23 while preventing the driving temperature of the main heater 27 from exceeding the limit temperature. have. According to this method, by providing a uniform evaporation amount without excessively increasing the temperature of the main heater 27, it is possible to reduce a change in film thickness over time according to the remaining amount of the raw material S. In other words, the controller C increases the driving temperature of the auxiliary heater 23 according to the remaining amount of the raw material S, so that the main heater 27 and/or the auxiliary heater 23 is It can be made to provide the amount of heat appropriate for each section (by height). Further, the control unit C may control the evaporation amount of the raw material S evaporated through the evaporation hole 221 by controlling the driving temperature of the auxiliary heater 23.

Meanwhile, FIG. 1 is a conceptual diagram of a film forming apparatus 1 for convenience of understanding, and an insulating material for preventing excessive heat transfer from the raw material supply unit 2 to the chamber where the substrate B is located. It should be noted that the structure of may be installed.

Likewise, the raw material supply unit 2 disclosed in FIG. 2 is also briefly illustrated, and although omitted in the drawing, the raw material supply unit 2 includes an insulating case surrounding the outside of the crucible 21 and the heaters 23 and 27, an insulating case, and It should be noted that a reflector or the like may be provided that is installed between the heaters 23 and 27 to concentrate heat generated from the heaters 23 and 27 toward the crucible.

5 and 6 are diagrams illustrating a state in which a raw material gas flows inside a raw material supply unit according to an exemplary embodiment.

Referring to FIGS. 5 and 6, the initial state and the mid-late state of the raw material S can be confirmed. First, when viewed in the vertical direction as a reference, the raw material S located above the liner 22 is evaporated according to the operation of the main heater 27. On the other hand, in the radial direction, the evaporation hole 221 may cause the raw material S located at the edge of the liner 22 to be consumed faster than the raw material S located at the center of the liner 22 There is this.

If the raw material S is in a solid state consisting of one lump, all of the raw material S adjacent to the evaporation hole 221 is exhausted, and an empty space is formed between the sidewall of the liner 22 and the raw material S. I can. In this case, there may be a problem in that the conductivity of heat transferred from the liner 22 to the raw material S is rapidly decreased. However, by using a powdery raw material (S) and forming a small diameter of the evaporation hole 221 so that the powdery raw material (S) is not lost to the outside of the liner 22, such a problem can be solved. Can be prevented. According to such a structure, as the film forming process proceeds, the raw material S at the edge portion of the liner 22 is first evaporated, but the powdery raw material S is an empty space (ie, the liner 22) by its own weight. By flowing down to fill the edge portion), it is possible to prevent a problem in which an air layer is formed between the side wall of the liner 22 and the raw material S.

The diameter of the evaporation hole 221 may be, for example, 0.5mm to 2mm. When the diameter of the evaporation hole 221 is less than 0.5mm, the evaporation effect is lowered, which is inefficient, and when it exceeds 2mm, the powdery raw material S may be lost. Therefore, the diameter of the evaporation hole 221 can be designed within the above-described range.

On the other hand, as the raw material S is exhausted as shown in FIG. 6, the height of the raw material S accommodated in the liner 22 gradually decreases, and when the film formation process is performed under the same conditions, the side surface of the liner 22 The amount of evaporation of the raw material S generated through may be reduced. In other words, as the evaporation amount of the raw material S supplied from the raw material supply unit 2 changes during the film formation process, there is a concern that the uniformity of film formation may be impaired.

In order to prevent such a problem, the controller C (see FIG. 1) may control the driving temperature of the auxiliary heater 23 based on, for example, the evaporation rate of the raw material S. In other words, the control unit C increases the driving temperature of the auxiliary heater 23 as the film forming process time elapses, so that the raw material S evaporated from the raw material supply unit 2 until the raw material S is sufficiently exhausted. It can be controlled so that the evaporation amount is uniform. For example, for determining the driving temperature of the auxiliary heater 23, the evaporation rate of the raw material S may be based on various previously measured data such as (i) the evaporation rate of the raw material S over time, or , (ii) a sensor that directly measures the rate of change in thickness of a film formed on the object to be formed, or (iii) a flow meter that measures the flow rate of the raw material (S) gas ejected from the raw material supply unit 2, and the like.

7 is a cross-sectional view of a raw material supply unit according to another embodiment, and FIG. 8 is a top view of the raw material supply unit illustrated in FIG. 7.

7 and 8, a raw material supply unit 3 according to another embodiment includes a crucible 31, a liner 32, a main heater 37, an auxiliary heater 33, a nozzle cap 35, and a middle A cap 36 may be included.

The crucible 31 may include a liner seating space, a cap seating space 213 and a support protrusion 314.

The liner 32 may include an evaporation hole 321 and a receiving portion 322.

For example, the evaporation hole 321 may be formed only on the lower side of the side surface of the liner 32. The area in which the evaporation hole 321 is formed may be within 25% of the total length of the liner 32 from the lower end of the liner 32.

According to this structure, since the raw material S can be continuously evaporated from the lower side of the liner 32, it is possible to prevent the raw material S located at the lower center of the material from deteriorating.

In addition, unlike the structures described in FIGS. 5 and 6, the height of the raw material S decreases as the film formation process proceeds, and the side surface of the liner 32 is removed until it is reduced to the area where the evaporation hole 321 is formed. The amount of evaporation of the raw material S through may be kept the same. In other words, since it is possible to provide a uniform evaporation amount for a sufficient time without adjusting the temperature of the auxiliary heater 33, the film formation process can be performed in a simple manner without various sensors for detecting the fluctuation of the evaporation amount. have.

For example, the cross-sectional area of the donut-shaped gap g is designed to be 90% to 110% of the sum of the area of the evaporation hole 321, so that the raw material S between the inlet and outlet ends of the donut-shaped gap g Prevent the problem of gas stagnation, and ensure that the velocity of the raw material (S) gas discharged through the donut-shaped gap (g) is the same as the speed of the raw material (S) gas discharged through the upper portion of the liner 22. I can.

9 is a cross-sectional view of a raw material supply unit according to another embodiment.

Referring to FIG. 9, a raw material supply unit 4 according to another embodiment includes a crucible 41, a liner 42, a main heater 47, an auxiliary heater 43, a nozzle cap 45, and an intermediate cap ( 46) may be included.

The liner 42 may include an evaporation hole 421, a receiving portion 422, an outer partition wall 423, an inner partition wall 424 and a cavity 425.

The outer partition wall 423 is a partition wall surrounding the receiving portion 422 for accommodating the raw material S therein, and can be understood as a portion forming the exterior of the liner 42. A first evaporation hole 4211 serving as a passage through which the raw material S is evaporated may be formed on the side of the outer partition wall 423 from the receiving portion 422 through the outer partition wall 423.

The inner partition wall 424 is a partition wall surrounding the cavity 425 in which the raw material S is not accommodated, and may be located inside the outer partition wall 423. The inner partition wall 424 may be understood as a member partitioning between the receiving portion 422 and the cavity 425. A second evaporation hole 4212 serving as a passage through which the raw material S is evaporated may be formed on the side surface of the inner partition wall 424 from the receiving portion 422 through the inner partition wall 424. Meanwhile, the first evaporation hole 4211 and the second evaporation hole 4212 may be collectively referred to as an evaporation hole 421.

According to such a structure, since it is possible to provide a higher evaporation amount through the two evaporation holes 4211 and 4212, productivity can be improved by dramatically improving the film formation speed.

In addition, it is possible to more efficiently reduce the problem of deterioration of the raw material S that may be generated by heat accumulated at the lower end of the center of the liner 42 during a long film forming process.

As described above, although the embodiments have been described by the limited drawings, various modifications and variations are possible from the above description to those of ordinary skill in the art. For example, the described techniques are performed in a different order from the described method, and/or components such as the described structure, device, etc. are combined or combined in a form different from the described method, or in other components or equivalents. Even if substituted or substituted by, appropriate results can be achieved.

Claims (21)

A liner capable of receiving raw materials;
A crucible having a liner seating space for seating the liner; And
By heating the crucible, it includes a main heater for heating and evaporating the raw material,
The crucible and the liner each have an open top surface,
An evaporation hole is formed on a side surface of the liner, and the raw material is evaporated through the evaporation hole as well as the upper portion of the liner, so that the material can be ejected to the top of the crucible.
The method of claim 1,
The longitudinal central axis of the crucible coincides with the longitudinal central axis of the liner, and the inner diameter of the crucible is formed larger than the outer diameter of the liner, so that a donut-shaped gap is formed between the crucible and the liner,
The raw material evaporated from the inside of the liner through the evaporation hole is in communication with the upper portion of the liner through the donut-shaped gap.
The method of claim 2,
The raw material supply unit, characterized in that the thickness of the donut-shaped gap is 0.5mm to 2.0mm.
The method of claim 2,
The raw material supply unit, wherein the cross-sectional area of the donut-shaped gap is 90% to 110% of the sum of the areas of the evaporation holes.
The method of claim 1,
The raw material supply unit is formed on at least one or more of the crucible and the liner, the raw material supply unit further comprising a support protrusion for preventing the liner from shaking inside the crucible.
The method of claim 5,
The support protrusion has a shape in which a cross-sectional area becomes narrower toward a direction in which the liner is inserted toward the crucible.
The method of claim 1,
The raw material supply unit further includes an auxiliary heater disposed at a position spaced downward from the main heater,
The main heater is positioned above the crucible to prevent the evaporated raw material from sticking to the upper side of the crucible.
The method of claim 7,
The raw material supply unit, wherein the main heater is driven at a temperature higher than that of the auxiliary heater.
The method of claim 1,
The raw material supply unit, characterized in that the thermal conductivity of the liner is lower than the thermal conductivity of the crucible.
The method of claim 9,
The material of the crucible is any one of graphite and pyrolytic boron nitride (PBN),
The material of the liner is a raw material supply unit, characterized in that any one of titanium (Ti), tantalum (Ta), stainless steel (SUS), and aluminum oxide (Al ₂ O ₃ ).
The method of claim 1,
The liner,
An outer partition wall surrounding a receiving portion for receiving the raw material therein; And
It surrounds a cavity in which the raw material is not accommodated and includes an inner partition wall partitioning between the receiving portion and the cavity,
The evaporation hole,
A first evaporation hole formed on a side surface of the outer partition wall and serving as a passage through which the raw material is evaporated from the receiving portion through the outer partition wall; And
A raw material supply unit including a second evaporation hole formed on a side surface of the inner partition wall and serving as a passage through which the raw material is evaporated from the receiving portion through the inner partition wall.
The method of claim 1,
The evaporation hole is a raw material supply unit, characterized in that formed only under the side of the liner.
The method of claim 12,
The raw material supply unit, wherein the region in which the evaporation hole is formed is within 25% of the total length of the liner from the lower end of the liner.
The method of claim 1,
The raw material supply unit further includes a nozzle cap positioned above the liner,
A raw material supply unit, characterized in that a nozzle hole having an area smaller than the upper surface open area of the liner is formed in the center of the nozzle cap.
The method of claim 14,
The raw material supply unit further includes an intermediate cap positioned between the nozzle cap and the liner,
The middle cap,
A plurality of intermediate holes arranged at a radially constant angle; And
A raw material supply unit located at the center of the plurality of intermediate holes and including an interference unit overlapping the nozzle hole in a direction perpendicular to the ground.
The method of claim 15,
The raw material supply unit, wherein the sum of the areas of the plurality of intermediate holes is smaller than the area of the nozzle holes.
The method of claim 15,
The crucible,
It has a larger diameter than the liner seating space, further comprising a cap seating space formed on the upper side of the liner seating space,
In a state in which the liner is seated in the liner seating space, the intermediate cap and the nozzle cap are sequentially seated and positioned in the cap seating space.
The method of claim 17,
The raw material supply unit, characterized in that the inner diameter of the intermediate cap is the same as the inner diameter of the liner seating space.
The method of claim 15,
The raw material supply unit,
When viewed from the side, the raw material supply unit further comprising a main heater disposed at a position overlapping the nozzle cap and the intermediate cap.
A raw material supply unit including a liner having at least a part of a side surface and an open upper surface, a crucible having an open upper surface and accommodating the liner, and a main heater for heating and evaporating the raw material contained in the liner; And
And a control unit that controls a driving temperature of the main heater based on the evaporation rate of the raw material.
The method of claim 20,
The raw material supply unit further includes an auxiliary heater disposed at a position spaced downward from the main heater,
The main heater is located on the upper side of the crucible to prevent the evaporated raw material from sticking to the upper side of the crucible,
Wherein the control unit is capable of independently controlling a driving temperature of the auxiliary heater and a driving temperature of the main heater.

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