JP2005256036A - Nozzle evaporation source for vapor deposition process, and vapor deposition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nozzle evaporation source for a vapor deposition process for improving the utilization rate of a material to be deposited by evaporation by improving the uniformity of a thickness of a material layer to be deposited by evaporation on a substrate in the nozzle evaporation source for the vapor deposition process, more particularly at the time of manufacturing of a large-sized substrate and preventing the sudden decrease in an vapor deposition rate of the material with lapse of time. <P>SOLUTION: The nozzle evaporation source for the vapor deposition process is provided with an insertion section 10 provided with nozzles 11 arrayed in a conical form to determine the evaporation direction of a chemical material, a furnace 20 which is disposed to a cylindrical shape opened on the upper side and is provided with a locking step to make the insertion section 10 insertable on the upper side, a filament 30 situated on the outer side of the furnace 20 to heat the furnace 20, a reflection plate 40 situated on the outer side of the filament 30 to minimize heat loss and a heat conduction section 50 inserted to the inner side of the furnace 20 and adapted to conduct the heat by the filament 30 down to the inner side of the furnace 20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a nozzle evaporation source and a deposition method for a deposition process, and more particularly to an evaporation source used in a deposition process for manufacturing a semiconductor element, a flat display element, and the like. The present invention relates to a nozzle evaporation source for a vapor deposition process and a vapor deposition method that uniformly vaporizes a material to be evaporated on a substrate and uniformly applies heat to the material inside the furnace.

  More specifically, when manufacturing a large-area substrate, it improves the uniformity of the thickness of the material layer deposited on the substrate, and prevents the material deposition rate from rapidly decreasing over time. The present invention relates to a nozzle evaporation source arranged in a conical shape for a vapor deposition process for increasing the utilization rate of a vapor deposition material.

  The deposition process is a method widely used in the manufacture of semiconductor devices and flat display devices. In order to coat the substrate with chemical substances used in the manufacture of semiconductor devices and flat display devices, chemical substances are contained. This is a method of forming a thin layer of a chemical substance on the substrate by heating the furnace and evaporating the chemical substance from the surface and depositing it on the substrate provided above the furnace. For the purpose of adjustment and efficient vapor deposition, the vapor deposition process is generally performed in a vacuum vessel.

  The most important part in the vapor deposition process is an evaporation source that heats a chemical substance as described above to evaporate the substance, and this evaporation source includes a furnace, a heating unit, and an opening. .

Examples of the evaporation source as described above include a point evaporation source, a linear evaporation source, and the like. Among these, the point evaporation source is most widely used.
As shown in FIG. 1, the conventional structure of the point-type evaporation source has an opening 2 which becomes narrower in a gourdate shape and is further widened in the upper part of a cylindrical furnace 1 whose lower side is closed for receiving a chemical substance. A heating part 3 for heating the furnace 1 is provided outside the furnace 1, and a nozzle part 4 is further provided in the opening 2 so that chemical substances are diffused widely. Also good.

In this manner, the heating unit 3 is heated to deposit the material while maintaining a predetermined distance from the substrate 5 to the point evaporation source.
The point-type evaporation source having the above-described structure has been widely used because it is easy to manufacture, but has a drawback that it is difficult to use for manufacturing a large-area substrate.

  The substrate of a semiconductor element is increasing in area, and in particular, in the case of a flat display element, a vapor deposition apparatus capable of manufacturing a large-area substrate is required to increase the size of a TV screen and improve productivity. In order to construct a vapor deposition system capable of manufacturing a large-area substrate, various technical problems must be solved. Among these, the development of an evaporation source for manufacturing a large-area substrate is the most important problem. It can be said.

  In the case of using the point evaporation source for manufacturing a large area substrate, for example, in order to deposit on a substrate having a size of 370 mm × 470 mm so that the uniformity of the thickness of the thin film is maintained within 5%. However, there is a problem that the point evaporation source must be separated from the substrate by about 1 m, the apparatus becomes large, and the utilization rate of the vapor deposition material becomes very low.

  In order to improve the above problems, as shown in FIG. 2, the substrate 5 is arranged so as to be deviated from the center of the evaporation source, or the substrate 5 is rotated. The problem of the evaporation source is not improved so much.

  Further, when the point-type evaporation source is used for manufacturing a large-area substrate, the furnace 1 should be enlarged and the volume of the furnace 1 receiving chemical substances should be increased. It becomes difficult for heat to be transferred to the chemical substance in the center of the furnace, and as shown in FIG. 3, only the chemical substance 6 near the inner wall of the furnace 1 is evaporated first, and a large amount of the chemical substance 6 remains in the furnace 1. However, since the deposition rate is significantly reduced, there is a problem that the chemical substance 6 must be filled frequently.

  The present invention has been made in view of the above-described problems, and in the nozzle evaporation source, in particular, the uniformity of the thickness of the material layer deposited on the substrate during the manufacture of the large area substrate is improved, and the material is deposited. It is an object of the present invention to provide a vapor deposition process nozzle evaporation source for preventing the rate from rapidly decreasing with the passage of time and improving the utilization rate of the vapor deposition material.

  In order to achieve the above object, the evaporation source nozzle evaporation source of the present invention determines the evaporation direction of a chemical substance, and a plurality of evaporation pipes penetrating downward and downward in the vertical direction are provided on the inside. An insertion portion connected to the evaporation pipe and provided with a nozzle arranged in a conical shape along the outer periphery of the upper side, and a locking stage provided in a cylindrical shape having an opening on the upper side and allowing the insertion portion to be inserted on the upper side A furnace provided with a filament, a filament for heating the furnace, located outside the furnace, a reflector located outside the filament for minimizing heat loss, and inserted inside the furnace And a heat conducting part for transferring heat from the filament to the inside of the furnace.

  According to the nozzle evaporation source for the deposition process of the present invention, the uniformity of the thickness of the material layer deposited on the substrate during the manufacture of the large area substrate is improved, and the deposition rate of the material is increased with time. Therefore, it is possible to prevent a sudden decrease and to improve the utilization rate of the vapor deposition material.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.
FIG. 4 is a cross-sectional view showing a furnace for a vapor deposition process nozzle evaporation source according to the present invention, and FIG. 5 is a cross-sectional view showing a first embodiment of the vapor deposition process nozzle evaporation source according to the present invention. The nozzle evaporation source for the vapor deposition process of the present invention determines the evaporation direction of the chemical substance. A plurality of evaporation pipes penetrating the lower side and the lower side in the vertical direction are provided inside, connected to these evaporation pipes, and the upper side A furnace provided with an insertion portion 10 provided with nozzles 11 arranged in a conical shape along the outer periphery thereof, and a cylindrical stage with an opening on the upper side, and provided with a locking stage 21 that allows the insertion portion 10 to be inserted on the upper side. 20, the outside of the furnace 20, the filament 30 for heating the furnace 20, the outside of the filament 30, the reflector 40 for minimizing heat loss, and the inside of the furnace 20 And a heat conduction part 50 for transferring heat from the filament 30 to the inside of the furnace 20.
In order to prevent the evaporating substance from leaking, the engaging step 21 can be formed with a screw thread (not shown) or the connecting portion can be sealed with a gasket.

FIG. 6 is a cross-sectional view taken along the line AA ′ of FIG. 4 and shows an example of the heat conduction portion of the nozzle evaporation source for the vapor deposition process of the present invention.
That is, the heat conducting unit 50 has a plurality of pins 51 that are in contact with the inner surface of the furnace 20 and whose end portions extend vertically toward the center side. The space surrounded by the pins 51 and the furnace By forming the space portions 52a and 52b on which the substance is placed at the center side of the heat 20, the heat transferred from the filament 30 outside the furnace 20 is also efficiently transferred to the chemical substance inside the furnace 20. The

  In the heat conduction part 50 shown in FIG. 6, the space part 52a on the center side of the furnace 20 has a substantially hexagonal shape, and the space part 52b surrounded by the pins 51 has a substantially octagonal shape. The spaces 52a and 52b are connected to each other, but may be various forms of heat conducting portions as shown in FIGS.

  That is, as shown in FIG. 7, the pin 51 is formed so that the space portions 52a and 52b are substantially circular, or as shown in FIG. 8, the structure of the pin 51 faces the center side. The space part 52 which comprises a structure and is enclosed by the said pin 51 may become a substantially triangular structure.

However, the structure of the heat conducting unit 50 is not limited to the structure shown in FIGS. 6 to 8, and it goes without saying that various embodiments are possible.
In some cases, it is preferable from the viewpoint of heat conduction efficiency that the heat conducting portion 50 is formed integrally with the furnace 20.

  FIG. 9 is a cross-sectional view showing a first embodiment of the insertion part of the nozzle evaporation source for the vapor deposition process of the present invention, and FIG. 10 is a cross-sectional view taken along the line B-B ′ of FIG. 9. The structure of the insertion part 10 is provided with a plurality of evaporation pipes 12 communicating with the lower side in the vertical direction, and the nozzle 11 is uniformly conically connected from the outside of the evaporation pipe 12 to the upper part of the insertion part 10. It is preferable to be formed.

Further, it is preferable that a circular reflector 13 is further provided on the upper side of the insertion portion 10 to improve thermal efficiency and prevent chemical substances from being stacked on the nozzle of the insertion portion 10.
In some cases, the circular reflector 13 may be formed in a plurality of layers.
A blocking plate 60 provided by a column 61 having a predetermined height may be further provided on the upper side of the circular reflecting plate 13 so that the flow of the chemical substance toward the center of the substrate can be adjusted.

FIG. 11: is sectional drawing which shows 2nd Embodiment of the insertion part of the said nozzle evaporation source for vapor deposition processes.
That is, in forming the insertion portion 10, the outer peripheral portion 10 a of the insertion portion 10 is provided in a concave shape so that heat can be more efficiently transferred to the evaporation tube 12 and the nozzle 11, and It becomes possible to prevent the substances from being stacked more efficiently.

  12 (a) and 12 (b) are partial enlarged views of FIG. 11. As shown in FIG. 12 (a), the nozzle 11 has a uniform width in the longitudinal direction or FIG. 12 (b). As shown, the width may increase in the longitudinal direction.

13 to 15 are cross-sectional views showing further embodiments of the nozzle evaporation source for the vapor deposition process of the present invention.
FIG. 13 shows a second embodiment of the nozzle evaporation source for the vapor deposition process of the present invention, in which a cylindrical hollow portion 70 penetrating the center of the insertion portion 10 and the furnace 20 is provided, and a central heating portion is provided in the hollow portion 70. 31 is provided. Both the filament 30 and the central heating part 31 can be provided, or only the central heating part 31 can be provided.

FIG. 14 shows a third embodiment of the present invention to which the embodiment of FIG. 13 is applied. A small small-sized evaporation having the same shape as the insertion portion on the upper side of the central hollow portion 70 in FIG. A source 80 is further provided, and another material is received in the small evaporation source 80 and can be applied to a process of depositing two materials at the same time.
At this time, a cooling unit (not shown) may be configured between the small evaporation source 80 at the center and the nozzle evaporation source arranged in a conical shape with a large outer shell in order to prevent thermal mutual interference. .

In addition, as shown in FIG. 15, the diameter of the column forming the hollow portion 70 can be further increased, and the shadow effect that can occur during the manufacture of a large-area substrate can be minimized.
That is, when a substrate is manufactured in the vapor deposition process, in order to determine the vapor deposition form on the substrate, the vapor deposition process is generally performed with a thin mask manufactured along the vapor deposition form in close contact with the lower side of the substrate. In the case of the conventional point-type evaporation source, the shadow effect of the mask may occur because the flow of the evaporating substance reaches the edge of the substrate in an uneven manner.

However, as shown in FIG. 15, when a cylinder with a large diameter is formed, the evaporation substance reaches almost all parts of the substrate almost vertically, so that the shadow effect that can occur when manufacturing a large-area substrate is minimized. The effect that can be obtained.
In addition, as described above, when the hollow portion 70 is enlarged, it is preferable to provide the filament 30 on both sides of the portion 22 where the substance can be received.

  On the other hand, the insertion part 10 may be provided integrally with the furnace 20, and in some cases, the intermediate part and the lower part of the furnace 20 may be separately connected.

The operation and effect of the present invention will be described below with reference to FIGS.
First, the operation principle of the entire nozzle evaporation source for the vapor deposition process of the present invention will be described.
As shown in FIG. 5, the filament 30 for heating the furnace 20 is preferably located above the furnace 20, which may be the evaporation tube 12 of the insertion portion 10 located above the furnace 20. This is because the nozzle 11 is heated more than the lower part of the furnace 20 where the evaporated substance evaporates, and the evaporation pipe 12 and the nozzle 11 are prevented from being blocked by the stack of evaporated substances.

In addition, the filament 30 may be provided on the lower side of the furnace 20 at a predetermined ratio so that the upper side and the lower side of the furnace 20 are heated uniformly.
Further, in order to uniformly evaporate the chemical substance from the surface, the outer surface of the furnace 20 that is filled with the chemical substance is not directly heated, but the upper part of the furnace 20 is heated to constitute the insertion portion 10. Evaporation is performed using radiant heat generated from the substance. In order to spread the radiant heat uniformly, the lower surface of the insertion portion 10 is preferably formed in a conical shape recessed upward.

  A shielding plate 60 is provided above the insertion portion 10 to adjust the size of the shielding plate 60 during the deposition process using the point evaporation source of the present invention to regulate the flow of the evaporating material toward the center. Thereby, it is possible to further adjust the uniformity of the deposited thin film and further increase the uniformity of the deposited thin film.

Hereinafter, an operation principle that can ensure the uniformity of the deposited thin film using the insertion portion 10 will be described.
In the case of a conventional point-type evaporation source, it is considered that the evaporating substance is emitted from one point and spreads upward in a hemispherical shape, and the evaporating substance flows slightly in the center of the hemisphere than in the outer part of the hemisphere . In addition, the substrate on which the vapor deposition is actually performed is a flat surface, and the distance from the evaporation source increases as the distance from the center of the substrate increases, and the angle between the flow direction of the evaporated material and the substrate surface increases. Therefore, the thickness of the deposited thin film becomes thinner as going from the center to the outer shell.

  In the case of the nozzle evaporation source for the vapor deposition process of the present invention, the nozzle 11 of the insertion portion 10 is formed in a conical shape toward the outer direction of the substrate, so that the flow of the evaporated substance further increases in the outer portion of the substrate. The influence of the distance between the evaporation source and the substrate and the angle between the flow direction of the evaporation substance and the substrate surface makes the central portion of the substrate thicker. It becomes possible to maintain the uniformity of thickness.

  At this time, the angle A between the nozzles arranged in a conical shape and the center line of the evaporation source can be selected as an appropriate angle in the range of 0 ° <A ≦ 90 ° depending on the distance from the substrate and the substance used. .

  In addition, a plurality of circular reflectors 13 positioned on the upper surface of the insertion portion 10 are provided in a stacked manner to increase the reflectance, thereby improving the thermal efficiency, and the nozzle 11 of the insertion portion 10 is higher than the upper portion of the furnace 20. It is possible to prevent a phenomenon in which the temperature is lowered and the nozzle 11 is clogged due to deposition of vapor deposition material or the like on the nozzle 11.

  The nozzle 11 and the furnace 20 of the present invention can be manufactured from high-density carbon, ceramic, or a material such as molybdenum, tungsten, tantalum, or titanium that does not easily sublime at a high temperature in a vacuum. It is also possible to use alloys.

  FIG. 16 is a diagram showing a fifth embodiment of the nozzle evaporation source for the vapor deposition process of the present invention. In the fifth embodiment of the present invention, as shown in FIGS. 16 and 18, a nozzle 90 inclined toward the outer direction of the substrate is provided in the insertion portion 10, and the evaporation source is positioned at or near the center of the substrate 5. The evaporation process is performed while rotating the substrate. That is, although the nozzle is biased to only one side, rotating the substrate 5 brings about the same effect as that in which nozzles arranged in a conical shape are formed.

  In addition to the asymmetric nozzle 90 shown in FIG. 16, the nozzle is biased using any structure that includes a nozzle 91 that is biased as shown in FIG. 17 and can adjust the ejection direction of the evaporated substance. May be. The angle biased with respect to the vertical center line A of the nozzles 90 and 91 may be in the range of 5 to 90 °, and the thin film to be deposited is considered in consideration of the distance between the height of the substrate 5 and the center of the substrate. Any angle may be used as long as the degree of uniformity is maximum.

  As mentioned above, although the said embodiment was described in detail with reference to drawings, this invention is not limited to this, It does not deviate from such a fundamental technical idea of this invention. Many other modifications will be possible to those skilled in the art to which the present invention pertains. Needless to say, the scope of the present invention should be construed in accordance with the appended claims.

Schematic which shows an example of the conventional point type evaporation source for vapor deposition processes. Schematic which shows the other usage example of the conventional point type evaporation source for vapor deposition processes. Schematic which shows the internal state of the furnace of the conventional point type evaporation source for vapor deposition processes. Sectional drawing which shows the furnace of the nozzle evaporation source for vapor deposition processes of this invention. Sectional drawing which shows 1st Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. FIG. 5 is a cross-sectional view taken along line A-A ′ of FIG. 4, showing a first embodiment of the heat conducting unit of the present invention. FIG. 5 is a cross-sectional view taken along line A-A ′ of FIG. 4, showing a second embodiment of the heat conducting unit of the present invention. FIG. 5 is a cross-sectional view taken along line A-A ′ of FIG. 4, showing a third embodiment of the heat conducting unit of the present invention. Sectional drawing which shows 1st Embodiment of the insertion part of the nozzle evaporation source for vapor deposition processes of this invention. B-B 'line sectional drawing of FIG. Sectional drawing which shows 2nd Embodiment of the insertion part of the nozzle evaporation source for vapor deposition processes of this invention. (A) And (b) is an enlarged view which shows the B section of FIG. Sectional drawing which shows 2nd Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. Sectional drawing which shows 3rd Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. Sectional drawing which shows 4th Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. Sectional drawing which shows 5th Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. Sectional drawing which shows 6th Embodiment of the nozzle evaporation source for vapor deposition processes of this invention. Schematic which shows the vapor deposition method using 5th Embodiment of the nozzle evaporation source for vapor deposition processes of this invention.

Explanation of symbols

10: Insertion part 11, 90, 91: Nozzle 12: Evaporation tube 20: Furnace 21: Locking stage 30: Filament 40: Reflection plate 50: Heat conduction part 60: Shielding plate 70: Hollow part 80: Small evaporation source

Claims (18)

A nozzle that determines the evaporation direction of the chemical substance, and is provided with a plurality of evaporation pipes that are vertically and vertically penetrated, connected to the evaporation pipe, and arranged in a conical shape along the outer periphery of the upper side. An insertion portion provided with,
A furnace provided in a cylindrical shape with an upper opening, and provided with a locking stage that allows the insertion portion to be inserted on the upper side;
It is located outside the furnace and comprises a filament for heating the furnace,
Nozzle evaporation source for vapor deposition process.   Inside the furnace, there is provided a heat conducting portion that is in contact with the inner side surface of the furnace, and whose end portion is directed toward the center side and extends vertically, and the space surrounded by the pins and the center of the furnace 2. The nozzle evaporation source for vapor deposition process according to claim 1, wherein a space portion on which a substance is placed is formed.   The evaporation source nozzle evaporation source according to claim 2, wherein the pins of the heat conducting part are provided at predetermined intervals, and the shape of the heat conducting part forms a geometric figure that is radially symmetric when viewed from above.   The evaporation source nozzle evaporation source according to claim 2, wherein the heat conducting part is formed integrally with the furnace.   The evaporation source nozzle evaporation source according to claim 1, wherein an angle A between the nozzle of the insertion portion and the center line of the evaporation source is in a range of 0 ° <A ≦ 90 °.   The insertion portion is composed of a plurality of tube-shaped nozzles penetrating the lower side, and the angle A between the tube-shaped nozzle and the center line of the evaporation source is arranged in a conical shape within a range of 0 ° <A ≦ 90 °. The nozzle evaporation source for a vapor deposition process according to claim 1.   2. The vapor deposition process nozzle evaporation according to claim 1, further comprising a circular reflector above the insertion portion to improve thermal efficiency and prevent chemical substances from being stacked on the nozzle of the insertion portion. source.   2. The heat transfer to the evaporation pipe and the nozzle is efficiently performed by forming the outer peripheral portion of the insertion portion in a concave shape, and the evaporation pipe and the nozzle are prevented from being blocked by the stack of evaporation substances. Nozzle evaporation source for the evaporation process.   The evaporation source nozzle evaporation source according to claim 1, further comprising a blocking plate provided by a pillar having a predetermined height above the insertion portion, wherein the flow of the chemical substance toward the center of the substrate can be adjusted.   The nozzle evaporation source for a vapor deposition process according to claim 1, wherein the lower surface of the insertion portion is formed in a conical shape recessed upward.   The evaporation source nozzle evaporation source according to claim 1, wherein the filament is located on the upper side of the furnace and heats the upper part of the furnace.   2. The nozzle evaporation source for a vapor deposition process according to claim 1, wherein the filament is distributed at a constant ratio between the upper side and the lower side of the furnace so as to maintain temperature uniformity on the upper and lower sides.   The nozzle evaporation source for a vapor deposition process according to claim 1, wherein a screw thread is formed in the locking step or a connecting portion between the furnace and the insertion portion is sealed using a gasket.   A columnar hollow portion that penetrates the insertion portion and the center of the furnace is formed, a central heating portion is provided in the hollow portion, and the filament and the central heating portion are provided together or only the central heating portion is provided for heating. The nozzle evaporation source for a vapor deposition process according to claim 1.   The small evaporation source having the same shape as the insertion portion on the upper side of the hollow portion is further provided on the upper side of the hollow portion, and the small evaporation source is filled with another substance so that two substances can be deposited simultaneously. Nozzle evaporation source for the evaporation process.   The nozzle evaporation source for a vapor deposition process according to claim 1, wherein the insertion portion is formed integrally with the furnace, or is divided and connected to an intermediate portion and a lower portion of the furnace. The direction of vaporization of the chemical substance is determined, and an insertion portion provided with a nozzle inclined at an angle of 5 to 90 ° with respect to the vertical center line;
A furnace formed in a cylindrical shape having an upper opening, and provided with a locking step that allows the insertion portion to be inserted on the upper side;
It is located outside the furnace and comprises a filament for heating the furnace,
Nozzle evaporation source for vapor deposition process. A method of depositing a thin film using the evaporation source of claim 17 or a conventional point evaporation source,
Step 1 of positioning the nozzle of the insertion portion adjacent to the center of the substrate or the center thereof toward the outside of the substrate;
Heating the evaporation source while rotating the substrate, and depositing a substance on the substrate.
Deposition method.

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