JP3093005B2 - Optical CVD equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming chamber provided with a substrate holding portion having a substrate heating means, a gas supply device for supplying a raw material gas into the film forming chamber, and a method for exciting the raw material gas.
The present invention relates to a photo-assisted CVD apparatus comprising a light source for irradiating the film forming chamber with an excitation light beam for supplying energy necessary for forming a thin film by decomposition.

[0002]

2. Description of the Related Art Conventionally, as a photo-CVD apparatus of this type,
As shown in FIG. 2, the substrate holding unit 2 is provided so that the film forming surface of the holding substrate 10 faces upward, and an optical path 6 into which the excitation light beam enters from the side along the holding substrate 10 is provided. A path for the source gas 3 flowing in from above the holding part 2 and flowing out of the holding part 2 is provided.

[0003]

In the above-mentioned prior art,
It is conceivable that the processing capacity is low and a plurality of substrate holding sections are provided to improve the capacity, or another substrate holding section is arranged above the substrate holding section so as to face the substrate holding section. However, in this case, as shown in FIG. 3, since the heat distribution is increased upward by the substrate heating means, the material gas convection toward the upper substrate surface or the raw material gas stagnating near the upper substrate surface causes , The film thickness formed on the upper substrate tends to be larger than the film thickness formed on the lower substrate. Further, in the configuration of the horizontal arrangement, the excitation light beam incident from the side entrance window into the film forming chamber is far from the irradiation window because its energy is attenuated as the source gas is excited and decomposed. There is a tendency that the thickness of the formed film becomes thinner as the position of the substrate increases. As described above, in the conventional technique, there is a disadvantage that the film thickness generated varies depending on the installation position of the substrate, and it is extremely difficult to control the film thickness to correct the variation in the film thickness. Accordingly, an object of the present invention is to provide an optical CVD apparatus capable of forming a thin film having a substantially uniform thickness on a plurality of substrates in view of the above-mentioned drawbacks.

[0004]

According to a first feature of the present invention to achieve this object, a plurality of substrate holders having substrate heating means are provided in the vertical direction and provided on the substrate holder. An excitation light beam irradiating means for separately irradiating a uniform excitation light beam along each of the substrates is provided, and a source gas from a gas supply device flows upward from the bottom of the film formation chamber along each substrate. Providing a path forming means so that the excitation light beam
From (5a) along a path along the surface of each substrate (10)
Where it is a flat laser beam bundle to be irradiated .
A second characteristic configuration of the present invention is that the excitation light beam irradiation means is formed by a distributor that distributes the excitation light beam emitted from the light source to a plurality of optical paths along the plurality of substrates. It is in.

[0005]

The film formed by the photo CVD method has the following properties depending on the difference in the film forming environment. That is, the lower the concentration of the source gas, the lower the film formation rate, and the higher the temperature of the source gas within the range where film formation is possible, the higher the film formation rate,
The higher the energy of the irradiation light, the higher the film forming speed.

Therefore, according to a first characteristic configuration of the present invention, a plurality of substrate holders having substrate heating means are provided in the vertical direction, and a raw material gas is provided along each substrate provided in the substrate holder. Is provided from the bottom to the top of the film forming chamber, so that
The ambient temperature is higher than the lower temperature due to the heat from the substrate heating means, and the raw material gas concentration is low because the raw material gas is consumed downward and the thinned raw material gas flows. On the other hand, in the lower part of the film forming chamber, on the contrary, the ambient temperature is lower than that of the upper part, and the source gas concentration is high because it is close to the source gas supply port.

[0007] The film forming rate is higher in the upward direction and slower in the lower direction from the distribution of the ambient temperature in the film forming chamber. In addition, when the film forming speed is viewed from the distribution state of the source gas concentration, the film forming speed is slower as it goes upward and becomes faster as it goes down. That is, the tendency of the film formation rate depending on the distribution of the ambient temperature and the tendency of the film formation rate depending on the distribution of the source gas concentration show opposite shapes, and each of them acts in such a manner as to negate the level of the film formation. In addition, the film forming rate can be made substantially constant regardless of the position of the substrate in the film forming chamber.

Further, since the excitation light beam irradiation means for individually irradiating a uniform excitation light beam is provided along each substrate provided on the substrate holding portion, a uniform state can be maintained for the atmosphere of each substrate portion. The excitation light beam can be irradiated, and accordingly, the film formation rate becomes almost constant on any substrate, and a film having a uniform thickness is formed.

According to a second feature of the present invention, the excitation light beam irradiation means is formed by a distributor for distributing the excitation light beam emitted from the light source to a plurality of optical paths along a plurality of substrates. Therefore, even with a single light source, it is possible to simultaneously irradiate the excitation light flux separately along the plurality of substrates, and a thin film can be formed on each substrate surface.

[0010]

As described above, according to the first aspect of the present invention, it is possible to collectively form a film having a substantially uniform thickness on a plurality of substrates at once, thereby improving the production efficiency. Became.

According to the second aspect of the present invention, a single light source can be used as a light source for forming a thin film on a plurality of substrates, and the cost of the apparatus can be reduced. It became so.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a film forming chamber 1 and a plurality of substrate holders 2 arranged vertically in the film forming chamber 1.
A gas supply device 4 for supplying a source gas 3 to the film forming chamber 1; a light source 5 for irradiating an excitation light beam for supplying a film forming energy to the source gas 3 in the film forming chamber 1; A distributor 7 which is an example of an excitation light beam irradiation means for distributing an optical path 6 of the excitation light beam from the light source 5 to a plurality of optical paths 6a, 6b, 6c along each substrate 10, and a vacuum suction in the film forming chamber 1. The optical CVD apparatus is provided with vacuum suction means 8 for performing the above.

A plurality of the substrate holders 2 are provided vertically in a holder main body in which a heater 9 as a substrate heating means is provided, and a silicon wafer 10 which is an example of a substrate is provided in the substrate holder 2. It is.

The light source 5 has an ArF wavelength of 193 nm.
It is composed of a laser 5a and an optical system 5b for shaping the output light beam into a flat parallel light beam. The shaped light beam 6 is divided into a plurality of optical paths 6a, 6b,
6c, is incident on the irradiation window 11 formed on the side of the film forming chamber 1 as an excitation light beam, and is irradiated along a path along the surface of the silicon wafer 10 of the substrate holding unit 2.

The raw material gas 3 from the gas supply device 4 is
A mixed gas of SiH ₄ and N ₂ O flows from an inflow port 12 provided in the lower part of the film forming chamber 1 so as to face upward, and rises along the silicon wafer 10. This inlet 12,
The vacuum suction means 8 constitutes a flow path forming means 13 for flowing the source gas 3 upward from below.

When the source gas 3 flows into the film forming chamber 1 maintained in vacuum by the vacuum suction means 8 and is irradiated with an excitation light beam, the source gas 3 is dissociated and heated by the heater 9. A thin film composed of SiO ₂ is formed on the silicon wafer 10.

[Another embodiment] Another embodiment will be described below.

The type of the source gas 3, the type of the substrate 10, and the type of the light source 5 are not limited to those in the above-described embodiment, but can be appropriately set according to the type of a thin film to be formed. For example, when SiH ₄ , NH ₃ or Si ₂ H ₆ , NH ₃ is used as the source gas 3, a Si ₃ N ₄ film can be formed.

In the above embodiment, the holder body 9 provided with a plurality of substrate holders 2 has been described. However, a holder body provided with one substrate holder 2 may be used. As long as the excitation light beam can be irradiated along the substrate 10, the holder main body may be provided in a facing position, in which case a thin film can be formed on more substrates 10 at one time. .

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of the apparatus.

FIG. 2 is a diagram showing a conventional example 1.

FIG. 3 is a diagram showing a second conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Film formation chamber 2 Substrate holding part 3 Source gas 4 Gas supply device 5 Light source 7 Excitation light beam irradiation means 9 Substrate heating means 10 Substrate 13 Channel formation means

Continuation of the front page (72) Inventor Shigeru Morikawa 17 Nakadoji Minamicho, Shimogyo-ku, Kyoto-shi, Kyoto Inside Kansai New Technology Research Institute Co., Ltd. (56) References JP-A-61-171120 (JP, A) JP-A-62-113417 (JP, A) JP-A-62-113418 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/205 H01L 21/31

Claims (2)

(57) [Claims] 1. A film forming chamber (1) provided with a substrate holder (2) having a substrate heating means (9), and the film forming chamber (1).
A gas supply device (4) for supplying a raw material gas (3) therein;
A light source (5) for irradiating the film forming chamber with an excitation light beam for supplying energy necessary for forming a thin film by exciting and decomposing the raw material gas (3); A plurality of holding parts (2) are arranged and provided in the vertical direction,
Along the respective substrates (10) provided on the substrate holder (2), an excitation light beam irradiation means (7) for individually irradiating a uniform excitation light beam is provided, and the excitation light beam irradiation means (4) from the gas supply device (4) is provided. A flow path forming means (1) for flowing a source gas (3) from below to above the film forming chamber (1) along each of the substrates (10).
3), wherein the excitation light beam is a laser light source (5a);
Irradiated along a path along the surface of each substrate (10)
An optical CVD device that is a flat laser beam bundle . 2. The excitation light beam irradiation means (7) is formed by a distributor for distributing an excitation light beam emitted from the light source (5) to a plurality of optical paths along the plurality of substrates (10). The optical CVD apparatus according to claim 1, wherein: