JPH01242771A - Vapor deposition material - Google Patents

Abstract

PURPOSE:To obtain a vapor deposition material free from scattering at the time of charging into a crucible and capable of uniform melting by forming the above vapor deposition material of granular titanium and also limiting the average grain size of the above. CONSTITUTION:Titanium 20 is previously formed into a nearly spherical shape of >=1mm average grain size and spaces among the titanium grains in a state charged into a crucible 21 are reduced to the utmost, by which Coulomb's repulsive force is balanced with the weight of the titanium grain 20 even if electric charges are stored at the time of melting in the crucible 21. By this method, the vapor deposition material free from scattering at the time of charging into the crucible and capable of uniform melting can be obtained.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to deposition materials used in deposition plating such as ion blating and vacuum deposition, and particularly relates to deposition materials for titanium thin film deposition and reactions such as TiN, Tic, T1CN, etc. The present invention relates to a material for titanium deposition used in ion blating treatment.

[Prior Art] Generally, when vapor deposition plating of titanium is performed, for example, an ion blating apparatus as shown in FIG. 3 is used.

The inside of a chamber 1 constituting this ion blating apparatus is maintained in a vacuum state, and nitrogen, carbon, etc. are supplied as a reaction gas 2.

This reaction gas 2 may be appropriately mixed with an inert gas such as argon for causing discharge.

At the bottom of the chamber 1 is an evaporation source 5 that generates an evaporation substance 4 by heating titanium 3 as an evaporation material to a temperature slightly higher than its melting point until a predetermined vapor pressure is obtained. is provided.

This evaporation source 5 is a so-called electron beam evaporation source that uses an electron beam 6, and is placed in a water-cooled crucible 7 containing titanium 3.
A vapor deposited substance 4 is obtained by directly shining an electron beam 6 on this and heating it.

Furthermore, a DC discharge electrode plate 8 having a higher potential than the crucible 7 is provided on the side wall of the chamber l.

This DC discharge electrode plate 8 is made of molybdenum, tantalum, tungsten, etc., and thermionic electrons 9 (
e-) is released and collides with the reaction gas 2 and evaporation material 11, these reaction gas 2 and evaporation material 4
It ionizes or excites the ions.

Furthermore, a deposition target substrate IO to be plated is arranged above the chamber l. This deposition target substrate IO has a lower potential than the crucible 7 and is heated by the heater 11.

Note that an openable and closable gloss 12 is provided between the evaporation source 5 and the deposition target substrate 10, and between the crucible 7 and the DC discharge electrode plate 8, and between the crucible 7 and the deposition target substrate IO. DC power supplies 13 and 14 are connected to each of them.

Further, reference numeral I5 in the figure indicates vacuum evacuation.

In the above configuration, the titanium 3 heated by the electron beam 6 becomes an evaporative substance 4 and evaporates into the chamber 1. At this time, thermionic electrons 9 (e-) emitted from the evaporation source 5 toward the DC discharge 7ri electrode plate 8 collide with the evaporation substance 4 to eject the electrons and become positive ions. Further, the reaction gas 2 is also positively ionized by the collision with the thermionic electrons 9.

The positively ionized evaporated substance 4 and the reaction gas 2 are attracted to the deposition target substrate 10 having a low potential, collide with each other, and combine to form a deposited film.

In this way, the ion blating device uses the evaporated material 4
Since it ionizes, it reliably attaches to the substrate 10 to be evaporated,
A strong plating with little change over time can be obtained.

Conventionally, titanium 3 was used as shown in FIG.
It is formed into a chip shape and placed in the crucible 7.

[Problem M to be solved by the invention] By the way, in the conventional technique described above, the titanium 3 is formed into a chip shape and put into the crucible 7. However, with this method, the titanium 3 is When the chips are placed in the crucible 7, gaps are created between the chips, and due to this, as shown in FIG. 5, some of the chips may remain undissolved in the lump during melting. The gaps between the chips remain as cavities, and the cooling temperature of the lumps cooled through the water-cooled crucible 7 becomes unstable, and as a result, the production of the evaporation substance 4 from the evaporation source 5 becomes unstable. However, there are still issues that need to be resolved, such as the possibility that this could have a negative impact on operations.

On the other hand, in order to avoid the formation of cavities when the titanium 3 is not melted or when it is melted, it is being considered to make the titanium 3 finer.

However, even with this method, after the finely divided titanium 3 is charged into the crucible 7, these titanium 3 are ejected from the crucible 7 for some reason and cannot be melted, and also they are scattered during the charging. However, there are still issues that remain, including the need for countermeasures to address these issues.

[Means for Solving the Problems] As a result of intensive research, the present inventors have determined that the scattering phenomenon during melting when using micronized titanium is caused by Coulomb repulsion due to the electric charges accumulated in titanium. The present invention was completed based on this assumption, and is particularly characterized in that the average particle size of the granular titanium is 1 mm or more.

[Function] The vapor deposition material according to the present invention has a mean particle diameter of 1 mm or more for the granular titanium, so that even if electric charges are accumulated during melting in the crucible, the Coulomb repulsion force and the The ff1ffi of the titanium grains is balanced to prevent the titanium grains from scattering, and the gaps between the titanium grains placed in the crucible are made as small as possible to enable uniform melting.

[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2.

The material for vapor deposition according to the present invention is obtained by molding crushed titanium 20 into a substantially spherical shape, or by molding it into a spherical shape in advance and dividing it into plates using a sieve, so that the particle size is 1 m.
m or more are used.

On the other hand, the maximum particle size is set based on other factors such as the shape and volume of the crucible 21.

When titanium 20 having such a particle size is put into the crucible 21, each titanium particle is small in diameter and approximately spherical, and as shown in FIG. 20 is closely packed to reduce the gaps between titanium grains.

Using the vL diameter of titanium 20 as a standard of 1 mm, we further divided the particle size into a certain range of particle sizes, and measured the dissolution status in each category, as shown in Table 1. The following results were obtained.

As is clear from the above results, when titanium particles having a particle size of 1 mm or more are used, stable dissolution can be obtained without scattering of the titanium 20.

In each of these particle sizes of 1 mm or more, as shown in FIG. 2, a nearly solid block 22 with no internal cavity was obtained.

As a result, the surface of the crucible 21 and the bottom surface of the titanium block 22 are brought into contact over almost the entire surface, and the electron beam heats and evaporates the block 22, and the crucible 21
The thermal balance between the cooling effect of the lumps 22 and the cooling effect via the cooling effect is stabilized, and good operation and film formation can be obtained.

These results depend on the shape and particle size settings of titanium 20.
Coulomb repulsion generated by charge accumulation and titanium 2
This is considered to be due to the fact that the weight of the titanium 20 is balanced with the weight of the titanium 20, and the ejection of the titanium 20 due to the Coulomb repulsion force is suppressed.

Furthermore, since the weight of each titanium grain is secured,
There was no scattering when charging into the crucible 21, and good handling was obtained.

[Effects of the Invention] As explained above, the vapor deposition material according to the present invention is a bone-like material used in an evaporation plating apparatus, and is made of granular titanium and has an average particle size of 1 mm or more. Because of this feature, it is possible to suppress the scattering of titanium particles during melting, and to suppress the formation of cavities in the obtained lump after melting, so that a stable melting operation can be performed. This makes it possible to form a good film, and also has excellent effects such as suppressing the scattering of titanium and making it easier to handle when charging the titanium into a crucible.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention,
Fig. 1 is a schematic diagram showing a state in which titanium grains of one embodiment are placed in a crucible, Fig. 2 is a schematic diagram showing a lump in the crucible after melting, and Figs. 3 to 5 are a conventional example. Fig. 3 is a schematic diagram showing the ion blating device, Fig. 4 is a schematic diagram showing a state in which titanium chips are placed in the crucible, and Fig. 5 is a schematic diagram showing the state in which titanium chips are placed in the crucible after melting. FIG. 20... Titanium, 21... Crucible, 2
2...Clumpy body. Figure 3 y-13

Claims (1)

[Claims] An evaporation material used in an evaporation plating device, which is made of granular titanium and has an average particle size of 1 mm.
A material for vapor deposition characterized by the above-mentioned features.