KR20090131384A - Top plate and apparatus for depositing thin film on wafer using the same - Google Patents

Abstract

PURPOSE: A gas spray assembly and an apparatus for depositing a thin film using the same are provided to prevent generation of particles inside a reactor or a shower head by individually controlling temperature of a gas flowed to a plurality of shower heads. CONSTITUTION: An apparatus for depositing a thin film includes a reactor(10), a substrate supporting part(20), and a gas spray assembly(80). The substrate supporting part is arranged inside the reactor. A plurality of substrate mounting parts is formed to a top surface of the substrate supporting part. The gas spray assembly includes a top lid(30), a plurality of shower heads(40), and at least two heaters(50). The top lid opens/closes the reactor. The shower heads are arranged according to a circumference direction of the top lid. Each shower head has a gas inflow hole, a gas diffusion space, and a plurality of gas spray holes. The heaters heat a gas flowed to the shower heads.

Description

Gas spray assembly and thin film deposition apparatus using the same {Top plate and Apparatus for depositing thin film on wafer using the same}

The present invention relates to a gas spray assembly for maintaining a constant temperature of the supplied gas while supplying gas to a substrate seated in the reactor and a thin film deposition apparatus equipped with such a gas spray assembly. A gas spray assembly and a thin film deposition apparatus used to allow a plurality of substrates to be processed together in a reactor.

As the scale of semiconductor devices is gradually reduced, the demand for ultra-thin films is increasing. As a thin film deposition method, an atomic layer deposition (ALD) method is in the spotlight. The atomic layer deposition method is a method of separating and supplying each source gas to a substrate to form a thin film by surface saturation of the source gases. A thin film deposition apparatus for implementing the above scheme is shown in FIG. 1. In particular, the conventional thin film deposition apparatus illustrated in FIG. 1 is capable of atomic layer deposition of several substrates simultaneously in one reactor.

Referring to FIG. 1, the conventional thin film deposition apparatus 9 includes a reactor 1 and a top lead 2 that opens and closes an inner space of the reactor 1. In the inner space of the reactor 1, a circular rotating plate 3 is installed to be rotatable and liftable. On the upper part of the rotating plate 3, a plurality of substrates w are disposed along the circumferential direction. A plurality of shower heads 4 are installed below the top lid 2. The gas introduced from the outside is supplied to the substrate w through the shower head 4. For example, the plurality of shower heads 4 may supply the first raw material gas, the purge gas, the second raw material gas, and the purge gas, respectively. When the rotating plate 3 rotates, the substrate w seated on the rotating plate 3 receives the first raw material gas, the purge gas, the second raw material gas, and the purge gas, and atomic layer deposition is performed.

On the other hand, one heater 5 is disposed above the top lid 2, and the heater 5 has a heat generation area capable of heating the entire areas of the plurality of shower heads 4, Many problems arise because the temperature of is controlled equally. Hereinafter, it will be described in detail.

In order to smoothly deposit the thin film, the raw material gas heated to the vaporization temperature by an external vaporization device and introduced into the shower head 4 in a gaseous state is maintained in a vaporized state in the shower head 4, and then the reactor 1 After being supplied to the substrate, it is decomposed by heating and deposited on the substrate w. For example, the raw material gas SiH ₄ containing the Si raw material is vaporized and introduced into the shower head 4, while maintaining a gaseous state in the shower head 4 and being fed into the reactor 1 and then heated to a decomposition temperature, the substrate It reacts with (w) to decompose into Si and H ₄ , so that Si is deposited on the substrate and H ₄ is discharged from the reactor 1. Accordingly, in order to prevent the temperature in the shower head 4 from cooling below the vaporization temperature and condensing the raw material gas or heating above the decomposition temperature to decompose the raw material gas, the inside of the shower head 4 should be maintained at an appropriate temperature. The heater 5 thus serves to maintain the proper temperature of the gas in the showerhead 4.

The problem is that in the conventional thin film deposition apparatus that processes several sheets at the same time, a plurality of different kinds of source gases are used, and since the vaporization temperature and the decomposition temperature are different for each source gas, the plurality of shower heads 4 If controlled at the same temperature, condensation or decomposition may occur in the showerhead, depending on the source gas. For example, when different types of raw materials 1 and 2 are used for thin film deposition, the vaporization temperature of the raw material 1 is 100 ° C., the decomposition temperature is 150 ° C., and the vaporization temperature of the raw material 2 is 200 ° C., and the decomposition temperature is 300. ℃. When the plurality of shower heads 4 are heated to 130 ° C. with the heater 5, the raw material 1 may maintain a gaseous state in the shower head 4, but is heated and vaporized to 200 ° C. or more to shower heads 4. The raw material 2 introduced into) is cooled in the shower head below the vaporization temperature and condensed to generate particles. Conversely, when the temperature in the shower head 4 is maintained at 200 ° C. or more, the raw material 1 is decomposed in the shower head to generate particles.

In the conventional thin film deposition apparatus 9, as described above, the entire heating region (plural showerheads) is controlled by the same heater 5, so that problems such as contamination due to particles have occurred. If the inside of the thin film deposition apparatus 9 is contaminated by particles, the quality of the deposited thin film is not only degraded, but also there is a problem in that it does not guarantee equipment stability.

The present invention is to solve the above problems, to provide a gas spray assembly and a thin film deposition apparatus using the same structure is improved so that it is possible to separate the temperature control for each source gas to suppress the generation of particles.

Gas injection assembly according to the present invention for achieving the above object, a plurality of top lids for sealing the reactor in which the substrate is mounted, arranged in the circumferential direction of the top lead is coupled to the top lead, the gas flows in A shower head and a shower head having a gas inlet hole, a gas diffusion space into which the gas introduced into the gas inlet hole is diffused, and a plurality of gas injection holes for injecting the gas diffused from the gas diffusion space into the substrate are formed. In order to heat the gas, it is characterized in that it comprises heating means for independently controlling the temperature of at least two mutually partitioned regions among the entire regions in which the plurality of shower heads are arranged.

According to the present invention, the heating means is respectively installed on the upper side of at least two shower heads of the plurality of shower heads to heat the gas introduced into the shower head, it is preferable that the heater independently temperature control.

According to the present invention, it is preferable that an insulator is installed on the upper side of the heater to prevent heat loss of the heater, and insulator is provided between the heater and the top lead so that heat generated from the heater is not transmitted through the top lead. It is more preferable to interpose.

In addition, the thin film deposition apparatus according to the present invention for achieving the above object, a reactor for forming a reaction space therein, a plurality of substrates are installed inside the reactor so as to be relatively rotatable with the top lead, the substrate is seated It is characterized by including the substrate support part formed in the additional upper surface, and the gas injection assembly of the said structure.

In the gas spray assembly and the thin film deposition apparatus using the same according to the present invention, a plurality of heaters operating independently of each other can be used to individually control the temperature of the gas, thereby preventing generation of particles due to condensation or decomposition of the gas. As a result, the quality of the deposited thin film is improved and facility stability is improved.

In addition, the gas spray assembly and the thin film deposition apparatus using the same according to the present invention has the advantage that the thermal efficiency is increased by preventing the heat of the heater to be lost.

Hereinafter, with reference to the accompanying drawings, a gas injection assembly 80 and a thin film deposition apparatus 100 according to a preferred embodiment of the present invention will be described. Since the gas injection assembly 80 according to the present invention includes the thin film deposition apparatus 100, the gas injection assembly 80 will also be described with reference to the thin film deposition apparatus 100.

2 is a schematic cross-sectional view of a thin film deposition apparatus 100 according to a preferred embodiment of the present invention, Figure 3 is an exploded perspective view of the main part of the thin film deposition apparatus shown in Figure 2, Figure 4 is IV- of FIG. It is a schematic sectional drawing of the IV line, and FIG. 5 is a schematic sectional drawing of the V-V line of FIG.

2 to 5, the thin film deposition apparatus 100 according to a preferred embodiment of the present invention includes a reactor 10, a substrate support 20, and a gas spray assembly 80.

The reactor 10 has a bottom portion 11 and an outer wall portion 12. The bottom portion 11 is formed in the shape of a disc, the outer wall portion 12 is formed extending vertically upward from the edge of the bottom portion 111 is made of a closed curved shape. The outer wall portion 12 is provided with a gate valve (not shown) through which the substrate w enters and exits. When the gas injection assembly 80 to be described below is coupled to the upper portion of the reactor 10, a reaction space 16 is formed inside the reactor 10, and thin film deposition is performed on the substrate w in the reaction space 16. . In addition, since the reaction space 16 must be maintained in a vacuum, an O-ring (not shown) is provided between the lower surface of the gas injection assembly 80 and the upper surface of the reactor 10 to prevent air from being introduced from the outside. A sealing member such as this is interposed.

In addition, an exhaust means for discharging unnecessary gas and particles remaining in the reactor 10 is provided in the reactor 10. An annular exhaust duct (not shown) is provided between the substrate support 20 to be described later and the inner surface of the outer wall of the reactor. Is preferably installed. The exhaust duct (not shown) is connected to an exhaust pump (not shown) through an exhaust port to forcibly exhaust unnecessary gas in the reactor 10.

The substrate support part 20 is for supporting and rotating the substrate w in the reactor 10 and is installed in the reaction space 16 therein, and the susceptor 21, the substrate seating part 22, and the shaft 23 are provided. ) And heating means (not shown).

The susceptor 21 is rotatably arranged inside the reactor 10 in the shape of a disc. The susceptor 21 is provided with a plurality of concave substrate seating portions 22, in particular six in this embodiment, in order to seat the substrate w. As shown in FIG. 5, the substrate mounting parts 22 are spaced apart from each other at predetermined angular intervals along the circumferential direction of the upper surface of the substrate support part 20. One end of both ends of the shaft 23 is coupled to the bottom surface of the susceptor 21, and the other end is connected to a rotating means (not shown) such as a motor through the reactor 10. Therefore, when the shaft 23 rotates, the susceptor 21 rotates about the rotation center axis A. In addition, the shaft 23 is connected to the lifting means such as a motor and a ball screw assembly (not shown), so that the susceptor 21 is also raised and lowered when the shaft 23 is lifted. Under the susceptor 21, heating means (not shown) for heating the substrate w is embedded.

The gas injection assembly 80 includes a top lead 30, a plurality of shower heads 40, and at least two heaters 50.

The top lead 30 serves to open and close the inside of the reactor 10, that is, the reaction space 16, and serves as a top plate. When the top lead 30 closes the reaction space 16, the reaction space is closed. do. The top lead 30 is coupled to the top of the reactor 10, but may be coupled in a detachable manner, but in this embodiment is hingeably coupled. The top lead 30 is formed in a substantially circular shape so as to correspond to the shape of the reactor 10.

In addition, a plurality of mounting holes 31 are radially disposed in the top lead 30 along the circumferential direction with respect to the center point. The mounting hole 31 is formed to penetrate between the upper and lower surfaces of the top lead 30, and the mounting hole 31 is formed in a substantially arc shape as a place where the shower head 40 to be described later is installed. In this embodiment, eight mounting holes 31 are arranged while maintaining a constant angular interval. In addition, when it is necessary to mount a shower head (for example, a purge gas injection shower head) in the center portion of the top lid 30, a mounting hole (not shown) may be formed, and the mounting hole disposed at the center is formed in a circular shape. do. In addition, depending on the deposition process, the size of the mounting holes may be different from each other, as well as the number of mounting holes may be different. That is, the size and number of mounting holes may vary depending on which film is deposited.

The shower head 40 is for injecting gas from the outside to inject gas into the substrate w mounted in the reactor 10, and is inserted into and installed in each mounting hole 31 provided in the top lid 30. . The gas introduced into the shower head 40 may be variously combined according to the process applied such as source gas, reaction gas, purge gas, and etching gas.

A gas inlet 42 is formed in the upper portion of the shower head 40 to introduce various gases into the shower head 40, as described above. It is connected to a supply device (not shown). In particular, between the raw material supply device for supplying the raw material and the gas inlet hole 42, a vaporization device for changing the raw material into a gas phase is generally interposed.

On the other hand, when the gas is supplied to the substrate w through the shower head 40, the gas is preferably introduced evenly over the entire area of the substrate w, the gas is introduced into a specific area is the uniformity of the film It is not preferable to lower. Accordingly, the gas diffusion space 41 and the plurality of gas injection holes 43 are formed in the shower head 40 so that the gas can be evenly introduced into the entire area of the substrate w. That is, the gas introduced through the gas inlet hole 42 is widely spread through the gas diffusion space 41 to the whole of the shower head 40, and the diffused gas is spread over the entire lower surface of the shower head 40. Through the gas injection hole 43 formed evenly, it is sprayed evenly to the whole area | region of the board | substrate w. In this embodiment, eight mounting holes 31 are disposed and described and illustrated as eight shower heads 40 are installed. However, the present disclosure is not limited thereto and may vary depending on the treatment process. .

The heater 50 is for heating the gas in the shower head 40, in particular, the source gas so that these gases can be maintained at a constant temperature. The heater 50 is installed above the shower head 40. In the present invention, the heater 50 At least two are provided. The two heaters 50 are each independently temperature controlled. In the present exemplary embodiment, two independent heaters are provided, but the heating values may be independently controlled by dividing the heating regions into at least two within one heater. That is, the heater in the present invention is only one example of a heating means capable of independently controlling the temperature by dividing the region in which the plurality of shower heads are arranged into at least two regions and heating the partitioned regions differently. Other means besides installing a plurality of heaters may also be employed as the heating means of the present invention as long as it performs the function of independent temperature control of the partitioned area as described above.

In the conventional thin film deposition apparatus, since all the shower heads are heated by using one heater, all the shower heads are formed at the same temperature, so that some gases may be condensed or decomposed in the shower head depending on the type of gas. In the present invention, a separate heater 50 is installed for each shower head 40 into which the raw material gas is introduced, thereby enabling independent temperature control for each raw material gas. Thus, as in the conventional thin film deposition apparatus, particles are generated in the shower head so that the problem such as contamination of the apparatus does not occur. The number of heaters 50 may vary depending on the number and type of gases used in the process, and more precisely, depending on the vaporization and decomposition temperatures of the gases.

On the other hand, the heat generated from the heater 50 is not used to heat the gas, it is necessary to prevent the thermal efficiency from being lowered by being released to the outside. Accordingly, the gas injection assembly 80 according to the present invention includes two insulators 61 and 62. That is, the upper part of the heater 50 is wrapped by the first insulator 61 so as to prevent heat from being discharged above the heater 50. In addition, a second insulator 62 is interposed between the heater 50 and the top lead 30 to prevent the heater 50 from being transferred from the heater 50 to the top lead 30. More precisely, the second insulator 62 is disposed between the top lead 30 and the shower head 40 to prevent heat transferred from the heater 50 to the shower head 40 to be transferred to the top lid 30. ) Is provided. Since the top lead 30 is generally made of a metal material having excellent heat transfer rate, the second insulator 62 may be installed to increase the thermal efficiency of the heater 50.

Hereinafter, a use example and operation of the thin film deposition apparatus 100 having the above-described configuration will be described. This use example is a case used for depositing an SrTiO ₃ film on the substrate w. In order to form the film described above, eight showerheads 40 are arranged. Of the eight shower heads, four first raw material gases including Sr, an O ₃ reactive gas, a second raw material gas including Ti, and an O ₃ reactive gas are spaced apart from each other, and N ₂ or Ar is disposed therebetween. It consists of four shower heads to which purge gas is supplied.

The first raw material gas containing Sr may be in various forms, but in this use example, the stable temperature maintaining the vaporization state is approximately 250 ° C. to 300 ° C. The second raw material gas containing Ti is a temperature at which 150 ° C to 200 ° C maintains a vaporized state, and a decomposition temperature is approximately 250 ° C. In the case of O _{3 which} is a reaction gas, when the temperature rises, it is reduced to O 2 so that the reactivity decreases.

According to the characteristics of the raw material gas, the shower head in which the first raw material gas is introduced and the shower head in which the second raw material gas is introduced should be temperature controlled independently of each other, and an independent heater is disposed on each shower head. . However, since the heating is not required in the shower head into which the reaction gas is introduced, the heater does not need to be disposed, and the heater does not need to be disposed in the shower head into which the purge gas is introduced. In this use example, two heaters are used.

When the device having the above-described configuration operates, the eight showerheads continuously supply gas, respectively, and the susceptor 31 rotates with the plurality of substrates w mounted thereon. The upper surface of the substrate w is exposed to the first raw material gas, the reactive gas, the second raw material gas, and the reactive gas to form a thin film. The heater disposed above the shower head to which the first raw material gas is supplied is heated to maintain 250 ° C. to 300 ° C., and the heater disposed above the shower head to which the second raw material gas is supplied is 150 ° C. to 200 ° C. It is heated so that it can be maintained. Accordingly, the first raw material gas, the second raw material gas, and the reaction gas can stably maintain the evaporated state without condensation or decomposition in the shower head.

Although the mounting hole 31 is formed in the gas injection assembly 80 and the shower head 40 is inserted and installed in the mounting hole 31, the shape of the gas injection assembly 80 is as described above. It is not limited to the form, various modifications are possible. This modified embodiment is shown in FIG. 6. 6 is a schematic view for explaining a gas injection assembly according to another embodiment of the present invention.

Referring to FIG. 6, unlike the above-described embodiment, the mounting hole is not formed in the top lid 30, and the first mounting portion 35 is concave on the bottom surface of the top lid 30, and the top lid 30 is formed. The second mounting portion 36 is formed concave on the top surface. The first and second mounting parts 35 and 36 are all arranged radially from the center of the top lead 30 along the circumferential direction. The shower head 40 is installed in the first mounting part 36, and the heater 50 and the first insulator 61 are installed in the second mounting part 35. In order to introduce gas into the gas inlet hole 42 of the shower head 40, a gas introduction path is formed through the first insulator 61, the heater 50, and the top lead 30. Has a configuration in communication with the gas inlet hole 42. Among the components illustrated in FIG. 6, the same reference numerals are used in the above-described embodiments, and thus description thereof will be omitted.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art. I can understand. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

1 is a schematic cross-sectional view for explaining a conventional thin film deposition apparatus.

2 is a schematic cross-sectional view of a thin film deposition apparatus 100 according to a preferred embodiment of the present invention.

3 is an exploded perspective view of the main part of the thin film deposition apparatus shown in FIG.

4 is a schematic cross-sectional view taken along the line IV-IV of FIG. 2.

FIG. 5 is a schematic cross-sectional view taken along the line VV of FIG. 2.

6 is a schematic view for explaining a gas injection assembly according to another embodiment of the present invention.

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

100 ... thin film deposition apparatus 10 ... reactor

20 ... substrate support 21 ... susceptor

30 ... Top lid 40 ... Showerhead

50 ... heater 61 ... first insulator

62 ... second insulator 80 ... gas injection assembly

w ... PCB

Claims (7)

A top lead for sealing the reactor on which the substrate is mounted; A plurality of gas is disposed in the circumferential direction of the top lead and coupled to the top lead. Shower head is formed with a plurality of gas injection holes for injecting the substrate; And Gas heating, characterized in that for heating the gas introduced into the shower head, the heating means for independently controlling the temperature of at least two of the divided areas of the entire region in which the plurality of shower head is disposed; Assembly. The method of claim 1, The heating means, Gas heater assembly, characterized in that the heater is installed on the upper side of the at least two shower head of the plurality of shower heads, respectively, to heat the gas introduced into the shower head, the temperature control independently of each other. The method of claim 2, And an insulator disposed above the heater to prevent heat loss of the heater.  The method of claim 2, And an insulator interposed between the heater and the top lead so that heat generated from the heater is not transmitted through the top lead. The method of claim 2, A plurality of mounting holes penetrating between the upper surface and the lower surface of the top lead is provided radially, the shower head is inserted into the mounting hole, the heater is disposed on the upper surface of the shower head, An insulator is installed between the shower head and the top lid and above the heater to prevent heat loss of the heater. The method of claim 2, A plurality of concave first mounting portions are radially disposed on a lower surface of the top lid, and the shower head is fitted to the first mounting portion. A plurality of concave second mounting portions are radially disposed on an upper surface of the top lead, and the heater is fitted to the first mounting portion, and an insulator is installed on an upper side of the heater to prevent heat loss of the heater. Gas spray assembly. A reactor forming a reaction space therein; A substrate support part installed in the reactor so as to be rotatable relative to the top lead, and having a plurality of substrate seating parts on which a substrate is seated; And A gas deposition assembly according to any one of claims 1 to 6;

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