JP2001271157A - Vapor deposition system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that, at vacuum deposition. application of excess energy to an evaporation source activates evaporation from the evaporation source, and not a few vapor deposition particles fly out in clusters and become vapor deposition splashes reaching a substrate, and these splashes cause the degradation of a deposit film and the hindrance of photolithography of he deposit film, although it is important to increase, for the forming of a deposit film having smooth and clean deposit surface, vapor-deposition particles to make negligible the influence of residual gas penetrated into the substrate a vapor deposition, i.e., to increase deposition rate and it is necessary to apply, for the increasing of deposition rate, excessive energy to the evaporation source, e.g. to increase the emission current of an electron beam at electron beam deposition. SOLUTION: In a vacuum deposition system, a mesh is provided between the evaporation source and the vapor-deposition substrate to prevent the deposition of the vapor-deposition splashes generated with the application of excess energy to the evaporation source on the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum evaporation apparatus having an electron beam heating evaporation source in a vacuum thin film forming method.

[0002]

2. Description of the Related Art There are many methods for forming a thin film, such as plating, printing in the air, and mechanical methods, in addition to thin film formation using a vacuum, and it has been developed as an important industry. The vacuum thin film forming method is important as an advanced thin film forming method among these methods. It is an important technology indispensable in the knowledge industry centering on electronics, the electronics industry, the watch industry, and the optical industry such as cameras. Therefore, research on the method of forming a vacuum thin film itself and its application is very active, and new methods are being developed one after another. Typical examples of a thin film forming method using a vacuum include an evaporation method, an ion plating method, a sputtering method, and a gas phase reaction method. Among the most widely used conventional techniques of the vacuum deposition apparatus are, for example, “Basics of Thin Film Preparation”, published in January 1977 by Nikkan Kogyo Shimbun,
As shown on page 85, there is an electron beam heating vacuum deposition technique. Vacuum deposition is similar to boiling water in a kettle and fogging the vapors on a window glass. Therefore, there is a deposition boat equivalent to a kettle, a heater for heating it, and a substrate on which evaporated vapor is attached.
Usually, a shutter is provided between the substrate and the vapor deposition boat to prevent impurities coming out of the substrate at the initial stage of vapor deposition from going to the substrate, and then the shutter is opened to attach a target thin film to the substrate. In order to heat the evaporant, a resistance heating method using heat generated by energizing a high melting point material such as tungsten and an electron beam heating method using an electron beam are mainly used. A vacuum is required to prevent oxidation of these hot objects. The material to be deposited is 1E-2 Torr in terms of vapor pressure.
Until the product is obtained, to a temperature which is slightly above the melting point, so to speak. Some sublimate below the melting point and others need to be above the melting point. When evaporating at a high speed, evaporate at a higher temperature. The characteristics of the deposited film include reflectance, specific resistance, hardness, crystal grain size, adhesive force to a substrate, and the like. In general, these properties include the deposition material, substrate type, substrate temperature, deposition rate,
The degree of vacuum, deposition angle, etc. have a significant effect. For example, as for the reflectance of the surface of the deposited film, when the deposition angle with respect to the substrate is large, the unevenness of the surface becomes large, and the reflectance decreases. When the degree of vacuum is low, moisture and oxygen increase the resistance of the deposited film and increase the hardness of the deposited film due to the influence of residual gas. The higher the substrate temperature, the larger the crystal grain size and the stronger the adhesion to the substrate. As a good vapor-deposited film property, a film having a strong adhesion to a substrate, a low resistance, and a low hardness is used. FIG. 2 schematically shows an electron beam heating evaporation source vacuum Al vapor deposition apparatus. The configuration of the electron beam heating evaporation source vacuum Al vapor deposition apparatus will be described with reference to FIG.

[0003] There is a bell jar 1 capable of holding a high vacuum, in which a substrate 3 is mounted on a substrate holder 2. The substrate holder 2 is grounded so that the Al particles heated and melted by the electron beam become charged, evaporate and adhere, so that no charge is accumulated. Inside the substrate holder 2, there is a substrate heater 4 for heating the substrate and for discharging gas in the bell jar. The vapor deposition boat 5 is filled with the vapor deposition material Al 6, and the electron beam 8 emitted from the electron gun 7 hits the vapor deposition material Al 6 of the vapor deposition boat 5 and heats and melts the Al. A shutter 9 is provided between the substrate and the evaporation boat to prevent impurities coming out of the initial stage of the evaporation from adhering to the substrate. When the evaporation source Al is sufficiently dissolved, the shutter 9 is opened and the substrate 3
An Al thin film is deposited on the substrate.

[0004]

The above-mentioned prior art includes the following:
When the Al thin film deposited on the substrate is deposited in a high vacuum, a clean film having a high reflectance can be obtained. Deposition at a low degree of vacuum results in a film having low reflectance. Even if the degree of vacuum is low, a film having a high reflectance can be formed by increasing the deposition rate. To increase the deposition rate, the emission current of the electron beam is increased, and the temperature of the evaporation source Al ingot is increased. When the temperature of the evaporation source Al ingot is increased, the evaporation of Al becomes active, the deposition rate is increased, and the splash of Al flying out in blocks increases. Some of the Al splash adheres to the substrate.
l By patterning of deposited film by photolithography, A
1 Splash is an obstacle. For example, photoresist cannot be uniformly applied. The contact between the mask and the substrate cannot be made uniform by contact exposure. There is a disadvantage that. The present invention is an electron beam heating vacuum deposition apparatus, in the process of forming a clean deposition film having a high reflectance by increasing the deposition rate,
The electron beam heating vacuum, which can form a high-reflectance, high-reflection, clean deposited film in the electron beam heating vacuum deposition apparatus, corrects the drawback that the evaporation material splash accompanying the higher deposition rate adheres to the substrate. An object is to provide a vapor deposition device.

[0005]

According to the present invention, in order to achieve the above object, in a vacuum deposition apparatus for heating an electron beam, a reticulated mesh is provided between a substrate and a shutter, and the evaporation source is heated with an electron beam. Splashes of the vapor deposition material generated by this are captured by a mesh-like mesh and are prevented from adhering to the substrate.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an electron beam heating Al vacuum evaporation apparatus in a surface acoustic wave resonator manufacturing process according to one embodiment of the present invention will be described with reference to FIG. The configuration of the electron beam heating Al vacuum evaporation apparatus will be described with reference to FIG. There is a bell jar 1 capable of holding a high vacuum, in which a substrate 3 is held by a substrate holder 2. The substrate holder 2 is grounded so that the Al particles heated and melted by the electron beam become charged, evaporate and adhere, so that no charge is accumulated. Inside the substrate holder 2, there is a substrate heater 4 for heating the substrate and for discharging gas in the bell jar. The vapor deposition boat 5 is filled with the vapor deposition material Al 6, and the electron beam 8 emitted from the electron gun 7 emits the vapor deposition material Al 6 of the vapor deposition boat 5.
, Al is heated and dissolved. A shutter 9 is provided between the substrate 3 and the deposition boat 5 to prevent impurities coming out of the initial stage of deposition from adhering to the substrate. When the evaporation source Al6 has sufficiently dissolved, the shutter 9 is opened, and an Al thin film is adhered to the substrate 3. There is a mesh mesh 10 between the shutter 9 and the substrate 3, and captures Al splash generated as a result of the evaporation source 6 being overheated by the electron beam 8.

According to the present invention, Al for a surface acoustic wave resonator is provided.
By increasing the deposition rate of the vapor-deposited film, a splash-free vapor-deposited film can be formed in a clean state where the reflectance of the vapor-deposited surface is high. In the present embodiment, the electron beam heating evaporation apparatus has been described, but the resistance heating evaporation apparatus,
It is clear that a similar effect can be obtained with a sputter deposition apparatus. Although Al is used as a vapor deposition material, other vapor deposition materials such as metal materials such as Cr, Au, and Mo, alloy materials such as Al—Si, Al—Cu, and nichrome, and silicon oxide and silver oxide It is clear that a similar effect can be obtained with a compound vapor deposition material or the like. Further, in this embodiment, the surface acoustic wave resonator has been described, but other surface acoustic wave elements, for example, A
The same applies to a deposited film used for manufacturing a semiconductor device. Further, in the present embodiment, the mesh is described for capturing the Al splash and preventing the substrate from adhering.
It is clear that the mesh effect can be obtained even if the mesh is, for example, a screen. Further, the configuration and configuration position of the components of the vapor deposition apparatus of the present embodiment are merely examples, and are not intended to limit the present invention.

[0008]

According to the present invention, when an Al vapor deposition film for forming a surface acoustic wave resonator interdigital transducer or an Al alloy vapor deposition film on a piezoelectric substrate by an electron beam heating Al vacuum vapor deposition device, the vapor deposition rate is increased and reflection is performed. Al is likely to be generated when the deposition rate accompanying the formation of a deposited film having a rate of 90% or more is increased.
The splash is captured by placing a mesh mesh between the evaporation source and the deposition substrate. This makes it possible to easily form an Al deposited film or an Al alloy deposited film having a reflectance of 90% or more without Al splash. When this sputtered Al deposited film or Al alloy deposited film having a reflectance of 90% or more is formed on a surface acoustic wave resonator interdigital transducer by, for example, a photolithography process, the linearity is improved.
A surface acoustic wave resonator interdigital transducer having a perpendicular cross section can be stably obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an Al vapor deposition apparatus using an electron beam heating evaporation source according to an embodiment of the present invention.

FIG. 2 is a diagram showing a conventional technique using electron beam heating evaporation source A;
1 is a cross-sectional view illustrating a vapor deposition device.

[Explanation of symbols]

1: bell jar, 2: substrate holder, 3: substrate, 4: substrate heater, 5: evaporation boat, 6: evaporation material Al,
7: electron gun, 8: electron beam, 9: shutter, 10: mesh.

Claims (6)

[Claims] 1. A high-vacuum airtight bell jar, a vacuum pump for evacuating the inside of the bell jar to a high vacuum, a substrate holder for holding a substrate to be deposited in the bell jar, a substrate holder in the bell jar and a substrate holder in the bell jar. In a thin film deposition apparatus comprising a heating device for heating a deposition substrate, and a gas discharging device in a bell jar, and an electron beam heating device for heating an evaporation source, between the substrate to be deposited on the substrate holder and the evaporation source,
A thin-film deposition apparatus comprising a mesh for controlling the start and end of vapor deposition, in addition to a shutter. 2. A thin film deposition apparatus according to claim 1, wherein a deposition rate is controlled by applying a positive electric field or a negative electric field to a mesh-like mesh between said substrate to be deposited and an evaporation source. Evaporation equipment. 3. A bell jar for maintaining a high vacuum tightness, a vacuum pump for evacuating the inside of the bell jar to a high vacuum, a substrate holder for holding a substrate to be deposited in the bell jar, a substrate holder for holding the inside of the bell jar and a substrate holder in the bell jar. In a metal thin film deposition apparatus comprising a heating device for heating a deposition substrate, and a gas discharging device in a bell jar, and an electron beam heating device for heating an evaporation source, the start of evaporation is performed between the evaporation source and the substrate to be deposited on the substrate holder. A metal thin film deposition apparatus characterized in that a mesh mesh is provided in addition to a shutter for controlling the termination. 4. A metal deposition thin film apparatus according to claim 3, wherein a deposition rate is controlled by applying a positive electric field or a negative electric field to a mesh-like mesh between said substrate to be deposited and an evaporation source. Metal thin film deposition equipment. 5. A bell jar for maintaining a high vacuum tightness, a vacuum pump for evacuating the inside of the bell jar to a high vacuum, a substrate holder for holding a substrate to be deposited in the bell jar, a substrate holder for holding the inside of the bell jar and a substrate holder for the inside of the bell jar. An Al vapor-deposited film or A comprising a heating device for heating a deposition substrate, a gas discharging device in a bell jar, and an electron beam heating device for heating an evaporation source.
In an l-alloy thin film deposition apparatus, a mesh-like mesh is provided between a substrate to be deposited on the substrate holder and an evaporation source, in addition to a shutter for controlling the start and end of vapor deposition, This is an Al alloy thin film deposition apparatus. 6. A deposition rate is controlled by applying a positive electric field or a negative electric field to a mesh mesh between the substrate to be deposited and an evaporation source in the Al deposited film or Al alloy thin film deposition apparatus. Al deposition film or Al alloy thin film deposition device.