JPS6096762A - Vapor deposition - Google Patents

Abstract

PURPOSE:To form a thin film having desired film thickness distribution by generating desired temp. distribution on a substrate, by using a vapor deposition material of which the adhesion rate is dependent on the temp. on the substrate and providing a reflection plate for adjusting quantity of heat from a heater for heating the substrate to the substrate to a predetermined position. CONSTITUTION:As a vapor deposition material 1, a material, of which the adhesion ratio of ZnS is dependent on the temp. on a substrate, is used and a reflection plate 4, which radiates heat to the substrate 2 from a heater 3 and partially reflects heat passing said substrate 2 to the side of the substrate 2, is provided in the side faced to the side of the heater 3' of the substrate 2 so as to cover said heater 3'. This reflection plate 4 covers almost the center part of the substrate 2 or one for covering the peripheral edge part of the substrate 2 is used. Therefore, when a large number of thin films each comprising single layer formed by a conventional method are stacked to form a multi-layered film having a non-uniform film thickness, treatment is performed as in the following. That is, a film comprising a single layer having film thickness distribution for setting off this non-uniform part is formed by this inventive method and stacked on the aforementioned multi-layered film to make it possible to obtain a multi- layered film having a uniform film thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a vapor deposition method for forming a thin film, and in particular a method for forming a thin film having a desired thickness distribution using a vapor deposition material whose deposition rate depends on the temperature on a substrate. The present invention relates to a vapor deposition method that can be used.

Technical Background of the Invention and Problems Therein Generally, when a thin film is formed by N deposition, an N deposition configuration as shown in FIG. 1 is used for the purpose of forming a uniform film thickness.

As shown in the figure, for one evaporation source 1 that heats and evaporates a material to be evaporated (hereinafter referred to as evaporation material), there are multiple substrates 2 on which a thin film is formed by depositing the ``C1 evaporation material''. They are arranged in axially symmetrical positions so that each can obtain an equal positional relationship with respect to the evaporation source 1. This is to ensure that all the thin films formed on each substrate 2 are homogeneous, and furthermore, each substrate 2 revolves around its axis (swivel motion), and each It is configured such that each arbitrary point on the substrate 2 rotates or rotates τ so that each arbitrary point on the substrate 2 can obtain an equal positional relationship with respect to the evaporation source 1.

3 and 3' are heaters that heat the substrate 2, and are used to increase the adhesion strength of the thin film to the substrate 2, and when the thin film is formed as an L (electroluminescence) element,
They are provided on both the front and back sides of the substrate 2 so as to heat it in order to enhance its light emitting characteristics.

By the way, when forming a single-layer thin film, it is possible to form a thin film with a sufficiently uniform thickness using the above-mentioned apparatus configuration. When forming a multilayer film by stacking multiple layers, it has been difficult to obtain a sufficiently uniform film thickness because even if there is a small error, the layers are stacked one on top of the other. Therefore, there is a need to develop a method for forming a single layer film with a desired thickness distribution in order to cancel out such non-uniform parts of the film thickness and form a multilayer film with an overall uniform thickness. .

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned circumstances of the prior art and to effectively solve the problems.

In other words, the present invention uses a material to be evaporated, such as zinc sulfide, whose deposition rate depends on the temperature on the substrate. A reflection plate is provided on the opposite side of the heater to adjust the amount of heat transferred from the heater to the substrate, and by creating a desired temperature distribution on the substrate, a thin film with a desired thickness distribution can be formed. The object of the present invention is to provide a vapor deposition method that allows the formation of

Embodiment of the Invention A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

First, Figure 2 is a graph showing the deposition rate as a function of the substrate temperature in terms of film thickness when zinc sulfide, which is also known as a typical material for EL elements, is used as the deposition material.The higher the substrate temperature, the lower the deposition rate. It is shown. In other words, the higher the substrate temperature, the thinner the formed thin film becomes.

FIG. 3 shows the configuration of an apparatus used in the vapor deposition method according to the present invention, and corresponds to FIG. 1 showing an example of the prior art. Therefore, similar components will be given the same numbers and redundant explanations will be omitted.

As shown in the figure, on the surface of the substrate 2 facing the heater 3- side,
A reflecting plate 4 is provided to cover this and partially reflects the heat radiated from the heater 3 to the substrate 2 and passing through the substrate 2 toward the substrate 2 side.

This reflecting plate 4 may be formed to cover approximately the central portion of the substrate 2 as shown in FIG. 4, or may be formed to cover the peripheral portion of the substrate 2 as shown in FIG. 5, for example.

Furthermore, as shown in FIGS. 6 and 7, if the edge portion 5 of the reflector 4 is slightly bent toward the heater 3' side, the boundary between the part covered by the reflector 4 and the part not covered by the reflector 4 can be , the slope of the concentration distribution can be changed continuously,
The film thickness distribution of the obtained iIM can also be a continuously changing distribution as shown in FIGS. 8 and 9.

Therefore, when a multilayer film with non-uniform thickness is formed by stacking many single-layer thin films formed by conventional techniques, it is possible to create a single-layer thin film with a film thickness distribution that offsets the non-uniformity. A multilayer film having a uniform thickness can be obtained by forming it by the method of the invention and superimposing it on the multilayer film described above.

In this example, the reflector was provided in contact with the substrate, but it goes without saying that even if the reflector is provided with a gap between them, the same action and effect as in this example can be obtained. It is.

In FIG. 3, the heater 3 on the side of the evaporation source 1 was considered as the heater that performs the main heating function when forming the desired concentration distribution on the substrate 2, but for example, the heater 3' on the opposite side was considered. If we consider it as the main heating source,
This can be used as a shielding plate instead of the reflecting plate 4, and the temperature distribution on the substrate 2 can be adjusted to block the radiant heat from the heater 3'. It is possible to obtain a temperature distribution that is the opposite of the above temperature distribution,
i of the M film formed! Film Thickness Distribution A film thickness distribution opposite to that of the previous embodiment can be obtained.

Effects of the Invention As is clear from the above explanation, the present invention provides the following excellent effects.

In other words, using a vaporized material such as zinc sulfide whose temperature depends on the temperature on the substrate, and from the heater heating the substrate to the opposite side with the substrate as a reference, Since a reflection plate is provided to adjust the amount of heat transferred to produce a desired temperature distribution on the substrate, a thin film having a desired thickness distribution can be formed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of an apparatus employed in a conventional vapor deposition method, and FIG. 2 is a graph showing the deposition rate of the vapor deposition material used in the vapor deposition method according to the present invention with respect to the substrate temperature in m thickness. 31st! ff is an explanatory diagram showing a schematic configuration of an apparatus used in the vapor deposition method according to the present invention, and FIGS. 4 and 5 are a plan view and FIG. Figures 6 and 7 are side views of Figures 4 and 5, respectively, and Figures 8 and 9 are v14 thickness distributions of thin films formed on the substrates shown in Figures 6 and 7, respectively. FIG. In addition, in the figure, 1 is an evaporation source, 2 is a substrate, 3.3' is a heater,
4 is a reflecting plate. Figure 1 Figure 2 T @ paddy 2-exhaustion (°C) Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] For an evaporation source of a deposition material whose deposition rate depends on the temperature on the substrate, a heater for heating the substrate is provided on the evaporation source side of the substrate, and a heater is provided on the opposite side of the substrate with respect to the substrate. , vapor deposition is performed by providing a reflective plate so as to adjust the distribution of the amount of heat transmitted from the heater to the substrate on the substrate to a desired distribution, and the film thickness distribution of the thin film of the vapor deposition material formed on the substrate is adjusted to the desired distribution. A vapor deposition method characterized by forming the film depending on the temperature distribution of the vapor deposition method.