JPH02220433A - Thin film formation device - Google Patents

Abstract

PURPOSE:To form a reproducible thin film by causing inner surfaces of a vessel for production of a plasma state, an extraction part for activating particles, a transport tube for activating particles, and the like to be made up by the surfaces made of a material having a chemical reaction resistance property. CONSTITUTION:Inner surfaces of a vessel for production of a plasma state, an extraction part 11 for activating particles, a transport tube 14 for the activating particles, and an introduction part 6 for electromagnetic waves are made up by the surfaces 61 made of a material having a chemical reaction resistance to the activating particles. In such a case, the surfaces 61 of the material having the chemical reaction resistance to the activating particles are formed by disposing, for example, a platelike or a sheetlike substance which is made of fused quartz or by forming coating layers of fused quartz on the inner surfaces of the vessel for production of a plasma state, the extraction part 11 for the activating particles, the transport tube 14 for the activating particles, and the introduction aperture 6 for electromagnetic waves. In this way no impurities are produced and then, reproducible thin films are formed by making its thin films hold prescribed characteristics.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a thin film forming apparatus that forms a film on a substrate by converting a source gas into plasma to generate activated particles and directing the activated particles toward the substrate.

[Conventional technology]

Conventionally, a thin film forming apparatus described below with reference to FIG. 5 has been proposed. That is, it has a plasma generation container 1 which is used to introduce raw material gas from the outside through a raw material gas introduction pipe 2 and to transform the raw material gas into plasma to generate activated particles. In this case, the plasma generation container 1 has conductivity, and
It has a window 3 that communicates with a film forming container 10 that will be described later. Further, it has an electromagnetic coil 4 as a magnetic field applying means for applying a magnetic field to the inside of the plasma generation container 1. In this case, Den U! The coil 4 is arranged around the plasma generation container 1. Further, electromagnetic waves (microwaves) are introduced into the container 1.
It has an electromagnetic wave introducing means 5. The electromagnetic wave introduction means 5 includes a plate-shaped electromagnetic wave introduction window 6 arranged to form a part of the plasma generation container 1, and a waveguide 7 extending from the electromagnetic wave introduction window 6 to the electromagnetic wave source. has. Roughly speaking, the substrate 8 is placed using a conductive substrate mounting table 9, and a window 12 is provided to communicate the activated particles generated in the plasma conversion container 1 with the window 3 of the plasma conversion container 1. It has a film-forming container 10 that is used to introduce activated particles toward a substrate 8 and form a film on the substrate 8 through an activated particle draw-out section 11 . In this case, the film-forming container 10 has electrical conductivity, and at the free end of the activated particle extraction section 11, via the insulating ring 15,
It is connected to the plasma generation container 1. In addition, the film forming container 10 has a substrate 8 when viewed from the substrate @ mounting table 9.
An exhaust pipe 13 connected to an external exhaust means is extended from the opposite side. Further, in the film forming container 10, an activated particle transport pipe 14 that extends from a position inside the activated particle extracting section 11 toward the substrate 8 side and has electrical conductivity is disposed. Further, a heater 6 is arranged on the substrate mounting table 9. The above is the configuration of a conventionally proposed thin film forming apparatus. According to the thin film forming apparatus having such a configuration, a substrate made of, for example, 3i is placed as the substrate 8 on the substrate & IE stand 9 in the film forming container 10, and the substrate 8 is heated by the heater 6. In addition, the inside of the film-forming container 10 is evacuated together with the inside of the plasma-generating container 1 through the exhaust pipe 13, and while the inside of the film-forming container 10 is maintained at the required pressure, the plasma-generating container 10 is A raw material gas such as SiH, for example, SiH is introduced into the chamber 1 through the gas introduction pipe 2 together with H2 gas, and a 2.45 MHz, for example, source gas is introduced into the plasma generation container 1 through the waveguide 7 and the electromagnetic wave introduction 116. A microwave having a frequency of By acting perpendicularly to the electric field, electron cyclotron resonance is generated in the plasma generation container 1, and therefore, the plasma generation container 1
The source gas introduced therein can be turned into plasma to generate activated particles. Further, the evacuation of the film forming container 10 generated as described above in the plasma forming container II is continued, and a substrate mounting table 9 is provided between the plasma forming container 1 and the substrate 8. , by applying a charged particle kinetic energy control voltage from the charged particle kinetic energy control power source 18 and further applying a focusing voltage from the focusing power source 19 to the activated particle transport pipe 14, the activated particles are transferred to the plasma conversion vessel. 1 into the film forming container 10 toward the substrate 8 , and the activated particle flow 17 passes through the activated particle extraction section 11 and the activated particle transport pipe 14 to the substrate 8 . It can be focused and reached. Therefore, [1] can be formed on the substrate 8.

Problems to be Solved by the Invention] However, in the case of the conventional ill formation apparatus shown in FIG.
Between the inside of the plasma generation container 1 and the substrate 8, contact is made with not only the inner surface of the plasma generation container 1 but also the inner surfaces of the activated particle extractor 11 of the film forming container 10, the plasma transport pipe 14, etc. And, at those contact parts,
There is a risk that it will react with the materials it is made of and generate undesirable impurities from those contact areas. For this reason, there is a risk that the activated particles may mix with undesirable impurities and reach the substrate 8, and therefore, it is not possible to form the ′;a crotch with desired characteristics with good reproducibility. It had the following drawbacks. Therefore, the present invention seeks to propose a novel thin film forming apparatus that does not have the above-mentioned drawbacks. Embodiment 1 Next, an embodiment of the thin film forming apparatus according to the present invention will be described with reference to FIG. In FIG. 1, parts corresponding to those in FIG. 5 are designated by the same reference numerals, and a detailed explanation will be omitted. The thin film forming apparatus according to the present invention shown in FIG. 1 has the same structure as the conventional thin film forming apparatus described above in FIG. 5, except for the following points. In other words, the plasma generation container 1, the activated particle extraction section 11
, the activated particle transport pipe 14, the electromagnetic wave introduction window 6, etc., the activated particles in the inner surfaces come into contact with each other, and react with the material constituting the activated particles at the contact area, and the desired release occurs from the contact area. At least a part of the region that is likely to generate impurities, and therefore at least the region that the activation particles come into contact with with relatively high energy, consists of a surface 61 of a material that is chemically resistant to the activation particles. For example, as shown in the figure, a plasma generation container, an activated particle extraction section 11, an activated particle transport pipe 14, and an electromagnetic wave introduction window 6
Their inner surfaces consist of a surface 61 of a material that is resistant to chemical reactivity towards the activated particles, since there is a risk that undesired impurities may be generated from the inner surfaces of the active particles. In this case, the surface 61 of the material that is chemically resistant to activated particles is on the inner surface of the plasma generation container, the activated particle extractor 11, the activated particle transport pipe 14, and the electromagnetic wave window 6. For example, it can be formed by disposing a plate-like or sheet-like body made of fused silica or by forming a coating layer of fused silica. The thin film forming apparatus according to the present invention having such a structure has the same structure as the conventional i1 film forming apparatus described above in FIG. 5, except for the above-mentioned matters.
Although a detailed explanation is omitted, the conventional 1il shown in FIG.
A thin film can be formed on the substrate 8 as in the case of the l* forming apparatus. However, since the thin film forming apparatus according to the present invention shown in FIG. It can be formed as having characteristics. This means that the above-mentioned thin film forming apparatus 61 according to the present invention
Ba1l for thin film formation is formed using a thin film forming apparatus having a thin film formation apparatus, and the concentration of oxygen impurities and carbon impurities in the substrate and the thin film formed thereon is set to VsI! When measured in the thickness direction, the results shown in the solid line in FIG. This is clear from the fact that the results shown by the dotted lines in FIG. 2 were obtained when the measurements were carried out. From the above, according to the thin film forming apparatus according to the present invention shown in FIG. 1, a thin film having desired characteristics can be easily formed on the substrate 8 with good reproducibility. For this purpose, the temperature of the substrate 8 is controlled by the current flowing through the heater 16, and the ion energy is controlled by the voltage of the ion energy 11 control power source 19, so that the thin film can be formed as shown in FIG. It was possible to successfully form an amorphous sm1 polycrystalline thin film and an epitaxially grown thin film. Note that the above description merely shows one embodiment of the thin film forming apparatus according to the present invention, and as shown in FIG.
In the configuration shown in FIG. 1, the activated particle transport pipe 4 and the substrate lit! A gas supply means 62 is extended between the mounting table 1 and the substrate 8 by activating the gas from the gas supply means.
The present invention is applied to a 7II film forming apparatus that cleans the substrate 8 and forms a thin film on the substrate 8, and in that case, the above-mentioned also applies to the required area on the outer surface of the gas supply means 61. It is also possible to adopt a structure having a surface 61 with a cylindrical surface 61, and various other modifications and changes may be made without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an embodiment of the PS film forming apparatus according to the present invention. FIG. 2 is a diagram showing the impurity concentration of a thin film for explaining the WII film forming apparatus according to the present invention shown in FIG. FIG. 3 is a diagram illustrating the growth mode of a thin film formed using substrate temperature and ion energy as parameters, to explain the thin film forming apparatus according to the present invention shown in FIG. FIG. 4 is a sectional view showing another embodiment of the thin film forming apparatus according to the present invention. FIG. 5 is a sectional view showing a conventional thin film forming apparatus. 1... Container for plasma generation 2...
... Raw material gas introduction pipe section 1 Fig. 3 ... Window 4 ... Electromagnetic coil 5 ... Electromagnetic wave introduction means 6 ... ..... Electromagnetic wave introduction window 7 ..... Waveguide 8 ..... Substrate 9 ..... Substrate @ mounting stand 10 ... ... Film-forming container 11 ... Activated particle extraction section 12 ...
...Window 14...Plasma transport pipe 16...
..... Heater 17 ..... Activated particle flow 18 ..... Power supply for controlling ion energy 19
......Focusing power source 20...Membrane 61...Surface 62...Gas supply means Fig. 2 8th WJ Saitaku Jhan&no)

Claims (1)

[Scope of Claims] 1. A plasma conversion container used for converting raw material gas into plasma to generate activated particles; A magnetic field applying means for applying a magnetic field within the plasma conversion container; an electromagnetic wave introducing means for introducing electromagnetic waves into a container; a substrate is disposed inside the container; and activated particles generated in the plasma generation container are introduced toward the substrate via an activated particle extraction section. In a thin film forming apparatus having a film forming chamber used for forming a film on the substrate, at least the activated particles in at least the wall of the plasma forming chamber and the inner surface of the activated particle drawing part 1. An apparatus for forming a thin film, wherein at least a part of a region with which activated particles come into contact with relatively high kinetic energy has a surface made of a material that is resistant to chemical reactivity with the activated particles.