JPS5920748B2 - Ion beam deposition device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ion beam deposition apparatus capable of forming high-purity coatings, and in particular to an ion beam deposition apparatus capable of forming high-purity coatings. By deflecting the ionized metal particles using a magnetic or electric field, ion beam deposition can form a high-purity film by selectively guiding only the desired ionized particles to the film-forming substrate. It is related to the device.

Conventionally, as an apparatus for forming a relatively thick ion deposition film, a glow discharge is caused in an inert gas atmosphere of about 10-4 to 10-2 Torr, and metal vapor is evaporated from an evaporation source by the generated gas ions. There is a known method that ionizes and deposits it on the surface of the material to be coated.

However, this device can only ionize less than 10% of the metal vapor deposited on the surface of the material.
There were drawbacks to the strength of the film, and impurities introduced from the evaporation source and other electrode materials were mixed into the deposited film. On the other hand, there are devices that apply the principle of a mass spectrometer to guide only pure metal ions to the material surface.
However, because the amount of metal ions that can reach the material surface is small, it could only be used to form very thin films or to implant impurity ions into semiconductor materials.

In this invention, most of the metal vapor is ionized by an electric discharge that passes through the metal vapor evaporated from the evaporation source, and then the ions are selected based on the principle of mass spectrometry. , and to efficiently produce a deposited film with high purity.

The present invention will be explained in detail below with reference to the illustrated embodiments.

FIG. 1 shows an example using an ionized particle sorting device using a magnetic field.

1 is a metal evaporation device, 2 is a crucible containing a metal 3 to be evaporated, and 4 is an electron beam generation source.

In the embodiment, the evaporator 1 is grounded. 5 is an ionization electrode, which is powered by an ionization power source 6 of 25 to 300
A positive voltage of V is applied.

A thermal filament 7 is installed near the ionization electrode 5 and between the ionization electrode 5 and the evaporator 1 . This hot filament 7 is used when the evaporation temperature of the metal 3 is low and a sufficient amount of thermoelectrons cannot be emitted from it. 9 is a shielding plate, and 10 is a passage hole for ionized particles formed in the shielding plate.

Reference numeral 11 denotes an ionized particle sorting device that utilizes the deflection effect of a magnetic field, and in the figure, a magnetic field is formed in a direction perpendicular to the plane of the paper.

12 is a substrate mask, 13 is a film forming substrate, and 14 is a substrate holder.

In this embodiment, a negative voltage is applied to the substrate holder 14 by a substrate power source 15, and thereby a negative voltage is applied to the film-forming substrate 13 with respect to the evaporator 1. 16 is a heater for heating the substrate, and 17 is a power source for heating the substrate.

The apparatus described above is typically placed in a vacuum of 10-5 to 10-1 Torr.

The electron beam 18 generated by the electron beam source 4 collides with the evaporated metal 3 in the crucible 2 to evaporate it. The metal particles generated by evaporation are ionized up to around 9096 by discharge through the metal vapor between the ionization electrode 5 and the metal 3 or the thermal filament 7, and the metal 3 or the thermal filament 7 radiates. Thermionic electrons assist in the discharge. The ionized metal particles 19 enter the ionized particle sorting device 11 through the ventilation hole 10 of the shielding plate 9 as an ion beam. In the ionized particle sorting device 11, each ionized particle is deflected by the action of a magnetic field. In this case, since the amount of deflection is determined by the mass of the particles, only ionized metal particles with a predetermined mass are selected, reach the film forming substrate 13 through the substrate mask 12, and are deposited thereon. be done. Substrate 13 as in the illustrated embodiment
When a negative voltage is applied to the substrate, the ionized particles are further accelerated by the negative voltage and collide with the substrate with high energy, forming a strong film. If it is necessary to prevent the substrate from being damaged by ionized particles striking the substrate 13, a positive voltage may be applied to the substrate 13 or it may be maintained at ground potential. Substrate heating heater 1
Reference numeral 6 is for controlling the growth state of the film formed on the substrate 13, and by appropriately controlling this heating temperature and the above-mentioned substrate voltage, it is also possible to grow, for example, a single crystal of silicon on the substrate 13. can. By the way, the deflection distance of ionized particles when utilizing the deflection effect of a magnetic field as shown in FIG. 1a can be expressed by the following equation with reference to FIG. 1b.

It is.

As is clear from this equation, the deflection distance t is determined by the mass of the ionized particles, so by appropriately determining the magnetic field strength H1, the acceleration voltage V1 of the ionization electrode, or the installation position of the substrate 13), Ionized particles having a predetermined mass, more specifically, only ionized particles of a desired material, can be deposited on the substrate 13, and a high-purity and high-strength film can be grown.

Moreover, since most of the evaporated metal particles are ionized, they can reach the substrate 13.
The coating is deposited with extremely high efficiency. FIG. 2 shows a second embodiment of the present invention, in which deflection means using an electric field is used as the sorting device 115.

This sorting device 1 is made up of two deflection plates 21 and 22.
A positive voltage is applied to one deflection plate 21 and a negative voltage is applied to the other deflection plate 22 by a deflection power source 23 . The structure of the other parts is exactly the same as that of the apparatus shown in FIG. 1, so the explanation thereof will be omitted. In this embodiment, although the ability to sort ionized particles according to their mass is small, only ionized particles can be deflected and guided to the substrate 13, so desired ion plating or ionization vapor deposition can be easily performed. can be done. As is clear from the above description, in the ion beam deposition apparatus according to the present invention, in addition to highly efficient ionization means by performing discharge through evaporated metal particles, the ion beam deposition apparatus uses evaporated ionized particles by applying the principle of mass spectrometry. Since the particles are sorted and guided to the substrate, all particles deposited on the substrate are made of ionized pure metal.

Therefore, the deposited metal film has a high density and high strength, and is also extremely pure1, and since most of the evaporated metal particles can reach the substrate, the film can be grown with extremely high efficiency. Can be done.

[Brief explanation of drawings]

FIG. 1a is a schematic diagram of a first embodiment of the ion beam deposition apparatus according to the present invention, FIG. 1b is a diagram explaining the operation of the ionized particle sorting device of FIG. 1a, and FIG. 1 is a schematic diagram of a second embodiment of an ion beam deposition apparatus according to the invention; FIG. DESCRIPTION OF SYMBOLS 1... Metal evaporator, 5... Ionization electrode, 11.
...Ionized metal sorting device, 13...Substrate.

Claims (1)

[Claims] 1. A vacuum chamber that maintains a high vacuum that virtually does not cause discharge due to atmospheric gas, a metal evaporation source placed in the vacuum chamber, and a metal vapor generated by the evaporation source placed near the evaporation source. an ionization electrode maintained at a positive voltage with respect to the evaporation source or the hot cathode so as to cause a discharge between the evaporation source or the hot cathode attached thereto, and a path for metal vapor particles ionized by the discharge; an ionized particle sorting device disposed therein that sorts out only ionized particles of a desired mass by a deflection action; and a substrate to which only ionized metal vapor particles sorted by the ionized particle sorting device are deposited. An ion beam deposition device consisting of: