JPS6063369A - Device for supplying solid source for evaporation in vapor growth apparatus - Google Patents

Abstract

PURPOSE:To expand the evaporation area of solid sources for evaporation by disposing a multi-stage shelf consisting of plural sheets of trays in a vessel for housing the solid source for evaporation and placing respectively the solid sources for evaporation on the respective trays. CONSTITUTION:A vessel 32 having an inflow port 17 and an outflow port 13 for carrier gas G is housed into a thermostatic chamber 34 which houses solid sources 15 for evaporation and evaporates the sources 15. A multi-stage shelf 33 disposed with plural sheets of trays 33a in multiple stages apart at a prescribed spacing from each other in a vertical direction is housed and disposed in said vessel 32. The solid sources 15 for evaporation are placed atop the respective trays 33a.

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to a method for forming a thin film on a substrate using a vapor phase growth method (CVD).
In particular, the present invention relates to a supply device (j4) for evaporating the solid for vaporization in a vapor phase growth apparatus into a stable gas and supplying the gas to a vapor phase growth chamber.

(b) Background of the technology For example, polysilicon (Polysilicon) has traditionally been used as a material for metal thin films formed on IC (integrated circuit) substrates.
5ilicon), alloys of Si and At, etc. have been frequently used. However, recently, Mo
, W + WSi2. Ta t Taxi, T
High melting point metals such as inT i and Si2 and their silicides (compounds with Si) are attracting attention, and for example, LSI (
It is being put into practical use as a material for dirt electrodes and wiring in large-scale integrated circuits. The reason is ^11 Mo.

Materials such as MoSi 2 have lower resistance than conventional materials such as polysilicon (for example, they have the advantage of greatly increasing the operating speed of ICs when fully formed, such as memory). , (2) Since it has a high melting point, it has advantages such as high durability in the ii1 ringing heating process in the IC manufacturing process. Thin film formation methods include vapor deposition,
Examples include sputtering method and vapor phase growth method (CVD method). Among these, the vapor phase growth method (including plasma CVD method) is superior in thin film formation and so-called step coverage (
That is, i't' of the stepped portion in the uneven portion on the substrate;
The film can be formed to have almost the same thickness as the thin film in the flat portion, and causes such as wire breakage can be prevented).

For this reason, in the future, the CVD method will have a finer pattern of 1t (1t).
Even when it is integrated, the above-mentioned advantages are taken advantage of, and there is a tendency for it to be used frequently.

Until now, metal thin films have been mainly formed by the steam method and the spackle method. However, collection 111i: 'f circuit <
14 The ability to improve precision and make patterns finer, step force
The CVD method is attracting attention in the future production of highly integrated ICs.

The CVD method uses heat, plasma, light, etc. to decompose the gas of the substance that forms the material that forms the film.
A film is formed when the reaction products land on the substrate. Regarding metals with high melting points, the vapor deposition method is difficult for 1ζ metals, which have a high melting point. For example, for Mo, CV made from Mo CZ s, which is a compound of MO.
There was a time when a film formation that surpassed that of the D method was successful and attracted attention. :)-! Shi, M.

The compound MoCZs can be used as a material for the CVD method (MoCAs, even MO itself, becomes a gas by sublimation at a much lower temperature, decomposes, and attaches MoF to the substrate. ), the MO itself is C
It cannot be used as a material for the VD method (Mo itself can be used as a composite material by vapor deposition or sputtering methods).

Therefore, in the CVD method, usually 1νio r
W.

MoCz5. WCl5, Tac
A low melting point material such as t5°T iCl 4 is used as a solid source for vaporization. Since these solid sources are solid at room temperature, it is important to stably supply the vapor (gas) into the vapor phase growth chamber in the case of gas sources (gas temperature) and liquid sources (liquid temperature). It's a waste of time in comparison. Therefore,
As a supply device for a solid source for vaporization in the CVD method, it is desirable that the solid source be of a structure that can evaporate (sublime) the solid source into a stable gas and send it into the vapor phase growth chamber. It is.

(c) Prior Art and Problems FIG. 1 is a diagram for explaining a supply device for a solid source for vaporization in a conventional vapor phase growth apparatus. In the figure, the prefix 10 indicates the entire vapor phase growth apparatus, and 11 indicates a supply device for a solid source for vaporization. The supply device 11 includes a bomb (container) 12 housed in a constant temperature bath 23 and a carrier gas G+ (for example, hydrogen (H2),
Alcon (Ar).

Ball l-1 containing 751c of force such as helium (He)
3 and outflow) 14, and a solid source for vaporization (e.g., a powder granular crystal of MoC45) stored in the +I pump 12. It is comprised of a constant temperature bath 23 for raising and maintaining the internal temperature of the pump 12 at a predetermined temperature (for example, about 90 DEG C. to 200 DEG C. in the case of yroct5).

And code 166: Carrier gas Gl passage, 1
7 is a passage 16 formed in communication with the middle of the passage 16.
M'i boat of fsu G2, 18 is a vapor phase growth chamber (chemical anti-C color chamber), 19 is a vapor phase growth chamber for exhausting the reaction gas of 18 yen, and maintaining the pressure 'c jft constant in the chamber 18. An exhaust port 20 for maintaining vacuum pressure is connected to a plurality of wafers (including a plurality of IC chips) arranged in the vapor phase growth chamber 18.
(substrate on which a film is formed), 21 is a holder for the wafer 20, and 22U wafer 2Of3: a heater for heating to a predetermined temperature. In Figure 1, cylinder 12
If the solid for vaporization #15 is MoCts, as mentioned above, MoCZs is
When heated to about 0.degree. C., it sublimates little by little and generates Mo CAs gas (steam).

This Mo C1s gas flows out together with the carrier gas G1 by the carrier gas Gr (in this case, referred to as H2) from the passage 16 through the passage 14, and along the way, it is diluted with a diluent gas G'2 (in this case, referred to as H2). The two are combined and sent to a vapor growth chamber (chemical reaction chamber) 1817'i.

Then, in the vapor phase growth chamber 18, the MoCt5 gas undergoes chemical reactions such as decomposition, reduction, and substitution.

A thin film of is formed on the wafer 20, and other reactant gases are exhausted through the exhaust port 19. Normally, when the usage time of the vapor phase growth apparatus 1001 ends, the constant temperature chamber 23 is turned off, heating of the cylinder 12 inside is stopped, and the internal temperature is lowered to room temperature until the next day's use. Ru. Therefore, the temperature of the solid source for vaporization in the cylinder 12 is repeatedly increased and decreased every day. As a result, in the case of this conventional example, the solid source J5 for vaporization is simply put into the cylinder 12 and deposited as shown in the figure, so the height of the piled up solid source 15 for vaporization is large. Mo CZ
The crystal grains of the powder particles of s tend to grow and become larger. Therefore, the surface area per unit weight of Mo C/-s decreases, and the evaporation (sublimation) surface becomes the upper surface 1 of the solid source 15 for vaporization.
Since it is only 5a, the amount of evaporation of MoC7s (sublimation stage)
An undesirable phenomenon occurs in which the initial value gradually decreases and changes. As a result, this conventional example has a problem in that the Mo 2 C7s gas cannot always be efficiently supplied to the full vapor phase growth chamber 18. This means that there are cases of JJ and 5 cases where the supply amount of Mo Ct 5 gas is insufficient and thin film formation cannot be performed efficiently.

The purpose of the present invention is to address the above-mentioned problems of the prior art, to improve the structure of the supply device for the solid source for vaporization, and to improve the evaporation (sublimation) of the solid source for vaporization in a cylinder with the same volume. ) Expansion of area (Figure 9) Supplying a supply device for a solid source for vaporization in a vapor phase growth apparatus that can constantly and efficiently supply the solid source gas for vaporization into the vapor phase growth chamber (chemical reaction chamber). It's about doing.

(E) Structure of the invention In order to achieve this object, according to the present invention,
A carrier gas inflow port and outflow port are installed in a constant temperature chamber that houses a solid source for vaporization and evaporates the solid source.
A multi-tiered shelf formed by arranging and fixing a plurality of shelf boards vertically at regular intervals in a multi-tiered manner is housed in the container, and a vaporizer is placed on the upper surface of each of the shelf boards. Provided is a supply device for a solid source for vaporization in a vapor phase growth apparatus, characterized in that a solid source for vaporization is mounted on each solid source for vaporization.

(F) Embodiments of the Invention Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 to 5 are diagrams for explaining the present invention in detail. In the figures, the same parts or corresponding parts as in FIG. 1 mentioned above are given the same reference numerals. Therefore, the code 13 is the carrier gas Gl (hydrogen (H2) l
Argon (Ar), helium (He) gas) inlet boat, 14 is 1. Output port 15 is a solid source for vaporization (Mock5. WCl2, TaCt5°T I
16 is a passage for carrier gas Gl; 17 is an inflow port for diluent gas G2 (gas such as H2, Ar, Fle, etc.) formed in communication with the passage 16; 18 is a vapor growth chamber (chemical reaction chamber), 1
9 is an exhaust boat for venting the reaction gas in the vapor growth chamber 18 and keeping the pressure in the chamber 18 at a constant vacuum pressure; 20 is a plurality of boats arranged in the vapor growth chamber 18; 21 is a holder for the wafer 21, and 22 is a heater for heating the wafer 20 to a predetermined temperature. Since it is the same as in Figure 1,
The explanation thereof will be omitted here.

In Figure SX2, the reference numeral 3o indicates the entire vapor phase growth apparatus, and the reference numeral 31 indicates a supply apparatus for a solid source for vaporization (purple).

The supply device 31 is housed in a constant temperature bath 34.
a cylinder 32, an inflow port 13 and an outflow port 14 for carrier gas G1 formed in the cylinder 32;
The internal temperature of the multi-tier shelf 33 accommodated in the cylinder 32, the vaporizing solid source 15 placed on the upper surface of the valley plate 33a of the multi-tier shelf 33, and the rW pump 32 is set to a predetermined temperature (
For example, when the solid source for vaporization is MoCls, the temperature is 90℃~
It is composed of a constant temperature bath 34 to maintain the temperature at a temperature of about 200°C. As shown in FIG. 3, the cylinder 32 consists of a cylindrical main body 32a and a canopy 32b. Note that the shape of the cylinder 32 is not limited to a cylindrical shape, and can be formed into any other shape, such as a rectangular cylindrical shape. As shown in FIG. 4, the large difference 32b is formed so that it can be easily attached to and detached from the main body 32a by means of a screw 32c provided on the outer periphery of the lower half, and is designed to simplify the loading and unloading of the multi-tiered shelf 33. A trench, Heaven? , ir, 32b may be formed to be openable and closable by using a hinge or the like in place of the screw 32c. On the upper surface of the canopy 32b is a carrier gas G! inflow boat 1
3 and outflow bow) 14 are planted. These ports 1
3゜14 is formed from a pipe member as shown in Fig. 2.
□Canopy 32bfd: It is planted through and communicates with the inside of the pond 32. As shown in Fig. 5, the multi-stage shelf 33 includes a plurality of disc-shaped shelf boards 33a arranged vertically at predetermined intervals, and a fixed shaft 33b extending through the center of the disc-shaped shelf boards 33a. In this case, it is formed into a multi-tier shelf with a five-tier structure. Note that the number of shelf boards 33a and the mutual spacing between each shelf board 33a can be arbitrarily selected as necessary. The outer diameter of the handle plate 33a is set smaller than the inner diameter of the main body 32a of the cylinder 32, and an appropriate gap is provided between the outer circumference of the shelf plate 33a and the inner circumferential surface of the main body 32a, so that the carrier gas G+ (see Figure 2) is designed to ensure good circulation.Therefore, each shelf board 3
The planar shapes of the portions 3a do not necessarily have to be the same, and may optionally be formed to have different shapes in order to improve the communication of the carrier gas G1.

As shown in FIG. 2, a vaporizing solid mt+
5. For example, place a small amount of Mo C1-5 in the form of powder particles. That is, this moving table is a solid source for vaporization 15.
The evaporation (sublimation) surface of fvio Ct5, which is
The amount of evaporation (amount of sublimation) of oCl3 is also increased by about five times.

In addition, the height of the Mo Cts deposited on the upper surface of each shelf plate 33a is smaller in the non-i hole than in the case of the above-mentioned il diagram, so the magnitude of the crystal growth of Mo CA 5 with respect to temperature changes is can be minimized. For this reason, Moc
It is possible to suppress the decrease in the surface area per A50 unit Mi amount, thereby minimizing the decrease in the amount of evaporation (sublimation 1k) of M o Cts.

(G) Effects of the Invention As described above in detail, the supply device IX for a solid source for vaporization in a vapor phase growth apparatus according to the present invention has a plurality of shelves in a container for storing a solid source for vaporization. A multi-tiered shelf consisting of plates is arranged, and a solid c for vaporization is placed on the upper surface of each of the shelves.
By mounting on the surface of the solid source for vaporization, the evaporation area of the solid source for vaporization can be greatly expanded in a container of the same volume, and crystal growth due to temperature changes in the solid source for vaporization can be suppressed to a minimum. As a result, it is possible to increase the evaporation h1: of the solid source for multi-vaporization, and it is also possible to suppress the decrease in the amount of evaporation compared to the initial amount of evaporation. It has great effects such as being able to stably supply gas to the four-sided membrane (1), and contributes to improving workability in the thin film forming process (2) and improving the quality of the film.

[Brief explanation of the drawing]

Figure 1 shows the vaporization j old δ in a conventional vapor phase growth apparatus fff.
Figure 2 is an explanatory diagram of the supply device for the solid source, and Figure 2 is the supply device I'i for the solid source for vaporization in the vapor phase growth device with one gate.
3 is a perspective view of the cylinder 32 shown in FIG. 2,
FIG. 4 is a simple J-plane view of the canopy 32b in FIG. 3, and FIG. 5 is a single view of the multi-tiered shelf 33 in FIG. 2. 13...Carrier gas (G+) inflow boat, 14
... υIL output port of carrier gas (G1), 1
5-... solid source for vaporization (MoCl5.WCl5.T
aCt5゜TICt4 etc.), 17.
...A1'i Inflow port for dilution gas (G2), 18...
・Vapor phase growth nK (chemically reactive group), 20...Multiple substrates (including an imaginary IC chip and on which a thin film of Mo or the like is formed), 30...Vapor phase growth according to the present invention Apparatus i, 31... Supply device for a solid source for vaporization in the vapor phase growth apparatus of the present invention, 32... Cylinder (storage container for a solid source for vaporization), 33... Multi-tier shelf, 33a... Shelf Board, 3
4... Constant temperature chamber, Gl... Carrier gas (hydrogen (H
2), argon (Ar). gas such as helium (He), G2... dilution gas (
gases such as H2, Ar, He, etc.). Patent applicant: Fujitsu Limited Patent agent Akira Aoki Patent attorney Kazuyuki Nishi Patent attorney 1) Yukio Patent attorney Akira Yamaguchi Figure 3 Figure 5 Figure 4 j/c

Claims (1)

[Claims] 1. A container having a carrier gas inflow boat and an outflow boat is housed in a constant-temperature cage that houses a solid source for vaporization and completely evaporates the solid source. A solid source for vaporization in a vapor phase growth apparatus, characterized in that multi-tiered shelves formed by arranging and fixing in multiple stages at predetermined intervals are housed, and a solid source for vaporization is placed on the upper surface of each shelf board, respectively. Feeding device.