JPH1088323A - Material for vapor deposition of silicon, its production and production of vapor deposited silicon film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material for vapor deposition of silicon for easily forming a high-purity vapor deposited silicon film, a process for production thereof and a process for producing the vapor deposited silicon film. SOLUTION: Metal silicon of 99.5% in Si purity and sodium silicate are mixed (step S1) and are kept charged for a prescribed period of time into a minus ionized quartz crucible, by which the mixture is minus ionized (step S2). When a slurry is formed by adding water to the minus ionized mixture (step S3), the mixture spouts of itself and its temp. rises up to 95 deg.C(step S4). Moisture is evaporated by the self-spouting. When the mixture is molded and cooled after resting in this state for a prescribed period of time (step S5), an ingot which is the material for vapor deposition of silicon is obtd. The vapor deposited silicon film is formed on the surface of a film base material by an electron beam heating type taking-up system vacuum vapor deposition method using this ingot (step S6).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for silicon deposition used for forming a high-purity silicon deposited film, a method for producing the same, and a method for producing a silicon deposited film.

[0002]

2. Description of the Related Art Metallic silicon (Si) is present in the ground next to oxygen, and its main ore, silica, is produced in various countries around the world. However, it is extremely difficult to obtain high-purity metallic silicon because both chemical and physical refining are extremely difficult. In general, chemical purification
The purification is carried out by using halides and hydrides which are easy to purify, and by reducing or thermally decomposing them. Silicon is chemically extremely active in a molten state (melting point: 1410 ° C.), and thus has many technical difficulties in physical refining and single crystal production. It is necessary to minimize the factors that cause contamination in the purification process, and it is important to pay close attention to the reagents, containers, and equipment used.

[0003] The raw material of high-purity silicon is not only the case where industrial silicon (97-98%) obtained by arc reduction of silica stone is used, but also silicon tetrachloride (S) which is a by-product of titanium industry.
iCl ₄ ) may be used. Silica, which is the primary raw material of high-purity silicon, is required to have a silica (SiO ₂ ) purity of 99.5% or more with few impurities such as Fe and Al.
By mixing carbon materials such as coal, coke, or wood chips, heating (1500-2000 ° C) and melting in an arc furnace, the following reduction reaction occurs, and metal-grade silicon (metal silicon)
Is obtained. SiO ₂ + 2C → Si + 2CO Table 1 shows the components of industrial silicon. A as an impurity
Materials such as 1, Ca, Mg, and B may be included. Table 2 shows impurities in the metal silicon.

[0004]

[Table 1]

[0005]

[Table 2]

A silicon oxide-based thin film composed mainly of silicon monoxide (SiO) or silicon dioxide (SiO ₂ ) exhibits excellent properties for electrical insulation and mechanical protection. Has been conventionally used as a vapor-deposited thin film of a packaging material in the field of (1). Further, since the silicon oxide-based thin film has transparency and gas barrier properties suitable for food packaging, its use as a surface coating for food packaging materials is increasing.

As a method for forming a silicon oxide-based thin film, a method is known in which powdery, granular, or massive silicon monoxide is heated, vacuum-deposited, and deposited on the surface of a packaging material. However, the silicon monoxide vapor-deposited film formed by this method has a refractive index of 2.0 to 2.2, and has many oxygen defects in the molecular structure in the film.
It is scattered to give a brown color and the transparency is not so good. Film composition significantly affect the transparency of the film, SiO _X film composition
It is known that when x is closer to 1, the color becomes browner, and as x is closer to 2, the color becomes more transparent. Further, silicon monoxide used in this method is expensive due to complicated production steps and poor productivity. As a result, the cost of raw materials increases, and there is a limit to the reduction in manufacturing costs.

Japanese Unexamined Patent Publication (Kokai) No. 2-122924 discloses, for example, SiO + Si ₂ O ₃ +
There is disclosed a method of forming a vapor-deposited film on the surface of a film by vacuum-depositing a mixed material of SiO ₂ by electron beam heating. This method, in addition to the problem of using SiO difficult to manufacture as described above, vapor pressure varies in the SiO and SiO _2, SiO ₂
Has a problem that its vapor pressure is lower than that of SiO. Therefore, there is a problem that the evaporation rate at the time of vapor deposition is low and the productivity is not excellent.

Further, Japanese Patent Application Laid-Open No. 63-310961,
The 166,965 discloses a metal silicon and silicon oxide, for example, Si and SiO ₂ These were mixed as a starting material, a method of forming a SiO _X film is disclosed on a surface of vacuum deposited film by heating. The vapor-deposited film obtained by this method has a non-uniform composition and poor evaporation characteristics, so that it is difficult to obtain a film having good characteristics.

In these two methods, a vapor deposition film having a composition containing a large amount of SiO ₂ is formed, so that the transparency is excellent.
Since SiO ₂ is in the form of silica-based glass, it has poor adhesion to the film surface. Conversely, when the amount of SiO ₂ is small, the adhesion is good, but the transparency is poor. Thus S
It is known that the transparency and adhesion of the film exhibit contradictory characteristics depending on the iO ₂ content.

Further, Japanese Patent Application Laid-Open No. 6-57417 discloses an evaporating material containing Si and a Si oxide and having a porous structure and a method for producing the same. In this method, a mixture of, for example, 40% of Si and 60% of SiO ₂ is used. After the mixture is made porous, the mixture is heated and deposited by, for example, an EB (electron beam) deposition method to form a deposited film. To form
This evaporating material has good evaporating properties and can evaporate at a high rate. Therefore, when coated by the EB evaporation method, a food packaging material which is transparent, has a small amount of oxygen permeation, and has no adhesion of flying substances. Can be produced with high efficiency. The composition of the deposited film obtained here is silicon oxide (S
iO _x ).

Further, a tech barrier manufactured by Mitsubishi Chemical Corporation has been put to practical use as one of the silicon-deposited films on which silicon is deposited. Tech barriers are available in several grades, for example for food and general packaging, pharmaceuticals and electronics. Table 3 shows the moisture permeability and oxygen permeability of the Tech Barrier, the aluminum foil composite film, and the aluminum vapor-deposited composite film.

[0013]

[Table 3]

In addition, a deposited film that can be used as a protective film for a semiconductor device and glass is required to be silicon (Si) instead of silicon oxide (SiO _x ), and is formed by sputtering using single crystal silicon as a raw material. doing. A deposited film having a film composition of Si is transparent and has high airtightness, as compared to a deposited film of SiO _X , since the arrangement of Si atoms is regular. In addition, since it has semiconductor properties (for example, photoelectric effect), application to a semiconductor device is also possible.

[0015]

In order to form a deposited film made of high-purity silicon by a sputtering method at a level usable for a semiconductor device, very expensive single crystal silicon is used. It is difficult to make it cheap. Further, in the conventional manufacturing method, a large-scale sputtering device must be used to form a vapor-deposited film made of high-purity silicon even if single crystal silicon is used, which cannot be easily manufactured. Also, the manufacturing cost including the device and power consumption is relatively high.

The present invention has been made in view of the above circumstances, and provides a material for silicon vapor deposition for easily forming a high-purity silicon vapor deposited film, a method for producing the same, and a method for producing a silicon vapor deposited film. The purpose is to:

[0017]

The material for silicon deposition according to the present invention is characterized in that silicon, sodium silicate and water are mixed.

Since the silicon vapor deposition material is porous, it easily sublimates and has good evaporation characteristics. Therefore, when this silicon deposition material is used, a high-purity silicon deposition film can be easily formed.Since the particle diameter at the time of forming the deposition film is small, silicon is deposited at a high density and the airtightness is good. is there.

In the method for producing a material for silicon vapor deposition according to the present invention, silicon and sodium silicate are mixed, charged into a negatively ionized quartz crucible for a predetermined time, and water is added to the negatively ionized mixture to spontaneously jet. It is characterized by making it.

The method for producing a silicon vapor-deposited film according to the present invention comprises forming a silicon vapor-deposited film by evaporating the silicon vapor-depositing material and attaching it to a film substrate, for example, by an electron beam heating roll-up vacuum vapor deposition method. Features.

The obtained silicon deposited film has a high silicon purity (95% or more) and has an amorphous or polycrystalline structure. Light scattering is small due to this crystal structure,
The silicon vapor deposition film is transparent and has low oxygen permeability because of the regular atomic arrangement. Furthermore, since it contains almost no impurities other than silicon, it is suitable not only for preserving food, protecting machinery, but also for use at the semiconductor device level. In addition, since it releases negative ions, an activating effect on a living body and an object can be obtained.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments. FIG. 1 is a flowchart showing the processing procedure of the method for producing a silicon vapor-deposited film according to the present invention. First, 1 kg of metal silicon having a Si purity of 99.5% (particle size: 5 × 10 ⁻⁸ to 2 × 10 ⁻¹ mm) and 50 g to 1 kg of sodium silicate are mixed (Step S1).
By putting the quartz crucible into a negative ion crucible for a predetermined time, the ion is negatively ionized (Step S).
2). When 50 cc of water is added to the anionized mixture to form a slurry (step S3), the mixture self-injects and rises to 95 ° C. (step S4). Here, if the amount of water is small, the slurry is not formed, and if it is too large, the viscosity of the slurry is too low. Moisture evaporates by self-injection, and after being left in this state for a predetermined time (20 to 30 minutes) and then molded and cooled (step S5), an ingot as a silicon vapor deposition material is obtained. Then, a silicon vapor-deposited film is formed on the surface of the film substrate by an electron beam heating-type winding vacuum vapor deposition method using the ingot (step S6).

The material for silicon deposition obtained in step S5 has good evaporation characteristics, so that it can be evaporated even in a normal CVD apparatus. The deposited film obtained using this material for silicon deposition has a high silicon purity of 95%,
Since it is a film deposition of a chemical species containing i atoms, it is mainly amorphous, but partially has a polycrystalline structure. For this reason, light scattering is small, and the silicon deposition film is almost transparent. In addition, since the atomic arrangement is dense and regular, the oxygen permeability is small, that is, the gas barrier property is good, so that it is suitable as a food packaging film. In addition, since oxygen permeability is small, it is also effective in preventing metal oxidation. Further, the high purity of silicon in the silicon deposited film makes it suitable for use in semiconductor devices such as solar cells, batteries, and capacitors.

Negative ions are released from silicon contained in the silicon vapor-deposited film according to the present invention, and it is considered that the negative ions activate oxygen in the surrounding air. An antibacterial effect is obtained by the action of the activated oxygen. Further, by the direct action of the active oxygen or the negative ion, the water, the tissue of the living body, or the substance existing in the vicinity is activated.

When there are many negative ions in the air, negative ions become alkaline atmosphere, and the biological action is as follows.
It has systemic effects such as sedation, exhilaration, hypnosis, and appetite enhancement, blood pressure lowering effect, blood sugar decreasing effect, vasodilatory effect, and diuretic promoting effect. Conversely, if there is a large amount of positive ions, it becomes a positive ion acidic atmosphere and has systemic effects such as excitement, discomfort, insomnia, loss of appetite, blood pressure increasing effect, blood glucose increasing effect, vasoconstrictive effect, diuretic suppressing effect, etc. It is said that.
In modern society, especially in urban areas, the concentration of positive ions tends to increase, and the number of people who complain of stiff shoulders and fatigue tends to increase.

Further, positive static electricity is neutralized or turned negative by negative ions, so that not only the above-mentioned biological action but also a substance can provide a good effect such as malfunction prevention in electric equipment.

Examples of application of the silicon vapor-deposited film for the purpose of obtaining these antibacterial effects, resuscitation effects, or far-infrared effects are listed below. The silicon vapor deposition film can be used in various forms, such as wrapping, laying, placing, attaching, attaching, etc. Food packaging wrap-Freshness preservation Metal packaging-Antioxidant Attached or placed on refrigerator-Antibacterial, freshness keeping Insole insole-Antibacterial Attached to the back of tatami-Antibacterial, insect repellent, low humidity Intrinsic in bedding-Sedating interior goods ( -Cushions, curtains, etc.)-Fatigue recovery Furniture-Insect control Pests installed on farmland (vinyl houses, hanging, etc.)-Growth promotion, pest control Pests installed in forests-Plant activation, pest control Pest protection for semiconductor devices-Static electricity control, impurity leakage Prevention, oxidation prevention

The negative ionization makes it easier for metal silicon and sodium silicate to be mixed, and this level increases as the degree of negative ionization increases.

[0029]

As described above, in the material for silicon deposition according to the present invention, silicon and sodium silicate are mixed and charged into a negatively ionized quartz crucible for a predetermined time, and water is added to the negatively ionized mixture. It is obtained by self-injection and has good evaporation characteristics. Further, by using this silicon deposition material, a high-purity silicon deposition film can be easily formed. The obtained silicon vapor-deposited film is transparent, has low oxygen permeability, and contains almost no impurities other than silicon. Therefore, it is suitable not only for preserving food, protecting machinery, but also for use at the level of a semiconductor device. The present invention has excellent effects such as the activation of living bodies and objects obtained by releasing ions.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a processing procedure of a method for manufacturing a silicon vapor deposition film according to the present invention.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Toyoko Ohara 7-538-18-18 Ayameikeminami, Nara City, Nara Prefecture (72) Inventor Hideaki Kikuchi 1-25-25 Taishibashi, Asahi-ku, Osaka-shi, Osaka

Claims (4)

[Claims] 1. A silicon vapor deposition material obtained by mixing silicon, sodium silicate and water. 2. A method comprising the steps of: mixing silicon and sodium silicate; charging the negatively ionized quartz crucible for a predetermined time; and adding water to the negatively ionized mixture and spouting the mixture by itself. A method for producing a silicon deposition material, characterized by comprising: 3. A step of mixing silicon and sodium silicate; a step of charging the negatively ionized quartz crucible for a predetermined time; and a step of adding water to the negatively ionized mixture and spouting it by itself. And e. Evaporating the obtained material for silicon vapor deposition and attaching the material to a film substrate to form a silicon vapor deposited film. 4. The method for producing a silicon-deposited film according to claim 3, wherein in the film forming step, an electron beam heating type vacuum deposition method using the silicon deposition material is used.