JPS62142777A - Formation of deposited film - Google Patents

Abstract

PURPOSE:To contrive economization of energy and easy control of film quality and to obtain an electrically insulating deposited film having uniform physical characteristics with excellent productivity and mass productivity even if the film has a large area by bringing gaseous raw materials contg. specific elements and gaseous halogen oxidizing agent into contact with each other to chemically form precursors. CONSTITUTION:The liquid or solid materials among the raw materials contg. Al, C, B or Zr which can be made gaseous state for forming the deposited film are gasified in a vessel 106 and are introduced into a vacuum chamber 120 and the gaseous materials are introduced from a cylinder 102 into said chamber, respectively through gas introducing pipes 109, 110. The gaseous halogen oxidizing agent which has the oxidation effect on the above-mentioned materials and is filled in a cylinder 103 is introduced by a gas introducing pipe 111 into the chamber 102 and is brought into contact with the above-mentioned materials to chemically form the plural precursors contg. the precursors in the excited state. The electrically insulating film is formed from >=1 such precursors as the supply source for the deposited film constituting element on a substrate 110 which exists in the film forming space of the chamber 120.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to monofunctional films, particularly for use in electronic devices such as semiconductor devices, photosensitive devices for electrophotography, and light input sensor devices for optical image input devices. Functional membrane useful for various applications
1ll formation method.

[Conventional technology]

Conventionally, amorphous or polycrystalline functional films such as semiconductor films, insulating films, photoconductive films, magnetic films, or metal films have been formed by forming films that are individually suited from the viewpoint of desired physical properties and applications. method has been adopted.

Vacuum evaporation method, plasma CVD method, thermal CVD method, photo CVD method, 2-reactive sputtering method, ion blating method, etc. have been tried to form the deposited film, but in general, plasma CVD method is widely used. It has become a corporate entity.

However, since the deposited films obtained by these deposited film formation methods are required to be applied to electronic devices and optoelectronic devices that require even higher functionality, they have improved electrical and optical properties, as well as durability during repeated use. There is room for further improvement in comprehensive properties in terms of productivity and mass production, including fatigue properties, use environment properties, uniformity and reproducibility.

The reaction process in forming a deposited film by the conventional plasma CVD method is the conventional so-called thermal carbon
It is considerably more complicated than the VD method, and the reaction mechanism is still unclear. In addition, there are many formation parameters for the deposited film (e.g., substrate temperature, flow rate and ratio of introduced gas, pressure during formation, high frequency power, electrode structure, reaction vessel structure, pumping speed, plasma generation method, etc.). Due to the combination of many parameters, the plasma sometimes becomes unstable, which often has a significant adverse effect on the deposited film formed. Moreover, it is necessary to select device-specific parameters for each device, making it difficult to generalize manufacturing conditions.

Among them, for example, in the case of amorphous silicon films, the plasma CVD method is currently considered to be the best method, since it can develop electrical and optical properties that fully satisfy each application. ing.

However, depending on the application of the deposited film, plasma CV
Forming a deposited film using the D method requires a large amount of equipment investment for mass production equipment, and the management items for mass production are also complicated, the control tolerance narrows, and equipment adjustments (sand absorption, etc.) are required. Therefore, these issues have been pointed out as issues that should be improved in the future.

On the other hand, the conventional technique using the normal CVD method requires high temperatures and has not been able to provide a deposited film with characteristics that are necessarily satisfactory at a commercial level.

These problems remain as a bigger problem, especially when forming an insulating film of a compound containing Al, C, B, or Zr.

As mentioned above, +1! In forming a functional film, it is strongly desired to develop a method for forming a deposited film that can be mass-produced using low-cost equipment while ensuring practical properties and maintaining uniformity.

〔the purpose〕

An object of the present invention is to eliminate the drawbacks of the above-mentioned method for forming a deposited film, and at the same time to provide a new method for forming a deposited film that does not rely on conventional methods.

Another object of the present invention is to provide a method for forming a deposited film that saves energy, allows easy control of film quality, and provides a deposited film with uniform characteristics over a large area.

Still another object of the present invention is to provide a method for forming a deposit 21 III, which is excellent in productivity and mass production, and can easily produce a film with high quality and excellent physical properties such as electrical, optical, and semiconductor properties. There is also.

[Means for solving problems]

The method for forming a deposited film according to the present invention which achieves the above object includes AfL, C, which can be made into a gaseous state for forming a deposited film.

By introducing a raw material containing B or Zr into a reaction space and bringing them into contact with a gaseous halogen acid and a stopper that have the property of oxidizing the raw material, the precursor in an excited state is chemically oxidized. The method is characterized in that an insulating film is formed on a substrate in a film forming space using the precursor as a supply source of deposited film components.

[Effect]

According to the deposited film forming method of the present invention described above, it is possible to save energy, increase the area, uniformity of film thickness, and uniformity of film quality, simplify management and mass production, and save a lot of money on mass production equipment. It does not require major capital investment, the control items for mass production become clear, the control tolerance is wide, and equipment adjustment becomes easy.

In the deposited film forming method of the present invention, A1. The raw material containing C, B or Zr is oxidized by contact with the gaseous halogen-based thickening agent, and the type and characteristics of the desired deposited film,
In the present invention, the above-mentioned raw materials and gaseous halogen-based oxidizing agents that can be made into a gaseous state may be selected as desired depending on the intended use, etc. In normal cases, it does not matter whether it is a gas, liquid, or solid.

When the raw material for forming the deposited film or the halogen-based oxidizing agent is liquid or solid, Ar.

He, N2. Using a carrier gas such as H2 and bubbling while adding heat if necessary, raw materials for forming a deposited film and a halogen-based oxidizing agent are introduced in gaseous form into the reaction space.

At this time, the partial pressure and mixing ratio of the gaseous raw material and the gaseous halogen-based oxidizing agent may be adjusted by adjusting the flow rate of the carrier gas or the vapor pressure of the raw material for forming the deposited film and the gaseous halogen-based oxidizing agent. Set by.

The raw material for the deposited film forming method used in the present invention is 1. For example, if a deposited film with good electrical insulation is to be obtained, organometallic compounds containing A, C, B, or Zr, hydrides, or Mention may be made of halides.

Specifically, the compound containing 11 is AM(CH3)
3, An (CH3) 2cl, A11 (CH3)
0 Sentence 2, AfL2 (CH3)2CSee3゜Al1 (
C2H5)3, AfL(C3H7)3.

A sentence (i-C3H7) 3, A sentence (i-C4H9) 3
.

AJI (OCH3)3, All (OC2H5)3
.

A sentence (0, C4H9) 3, A sentence CfL3゜AJIBr
3. Compounds containing Aul3, C include CH4, C2
H6, C3H8, C-4H10゜C2H4, C3He
, C4H8, C2H2.

As a compound containing C3H4, B.

B (CH3)3, B (C2H5)3.

B (C3H7)3 , B (C4H9)3
.

B (OCH3)3, B (OC2H5)
3.

B (i-OC3H7) 3 , B (0-C4H
9) 3.

B2H6, BCJL 3 , B, Br 3 , BI
3. As a compound containing Zr, Zr (CH3)4
.

Z r (C2)1s)a, Z r (C3H7)4
.

Zr (C4H9) 4, Z’r (OCH3) 4.

Zr (OC2H5) 4. Zr (OC3H7) 4
゜2 r (OC4H9)4, Z r (CH3)
2(C5H5)2, zrc12(CsHs)2, and the like.

Of course, these raw materials can be used not only alone, but also as a mixture of two or more.

The halogen-based oxidizing agent used in the present invention is in a gaseous state when introduced into the reaction space.

At the same time, F2. CfL2Br2. I2. Effective examples include halogen gas such as C-F, nascent fluorine, chlorine, and bromine.

These halogen-based oxidants are in gaseous form, and are introduced into the reaction space together with the gaseous raw material for forming the deposited film at a desired flow rate and supply pressure, and mixed and collided with the raw material. , the raw material is oxidized to efficiently generate a plurality of types of precursors including excited state precursors. The excited state precursors and other precursors that are generated serve as a source of components for the deposited film in which at least one of them is formed.

The generated precursor decomposes or reacts to become a precursor in another excited state or a precursor in another excited state, or is deposited in that form, although it releases energy as necessary. By touching the surface of the substrate disposed in the space, a deposited film having a three-dimensional network structure is created when the substrate surface temperature is relatively low, or a crystalline deposited film is created when the substrate surface temperature is high.

In the present invention, the type and type of raw material and halogen-based oxidizing agent are selected as film-forming factors so that the deposited film forming process can proceed smoothly and a film with high quality and desired physical properties can be formed. The combination, their mixing ratio, the pressure during mixing, the flow rate, the internal pressure of the film-forming space, the waveform of the gas, and the film-forming temperature (substrate temperature and ambient temperature) are appropriately selected as desired.

These film-forming factors are organically related and are not determined independently, but are determined depending on each other in relation to each other.

In the present invention, the ratio of the amounts of the gaseous raw material for forming a deposited film and the gaseous halogen-based oxidizing agent introduced into one reaction space depends on the relationship between the film formation factors and the intermediate speed of the film formation factors mentioned above. Although it can be determined as desired, the introduction flow rate ratio is preferably 1/20 to 100/1, more preferably 175 to 50/1.

The pressure at the time of mixing when introduced into the reaction space is preferably higher in order to increase the probability of contact between the gaseous raw material and the gaseous halogen-based oxidizing agent, but taking into account reactivity. It is preferable to determine the optimum value as desired. The pressure at the time of mixing is determined as described above, but the pressure at the time of each introduction is preferably lXl.
0-7 atm to 5 atm, more preferably I x 10-6
It is desirable that the pressure be between atmospheric pressure and 2 atmospheric pressure.

The pressure in the film-forming space, that is, the pressure in the space where the substrate on which the film is to be formed is disposed, is the pressure of the excited state precursor (E) generated in the reaction space and, if necessary, the precursor. The precursor (CD) derived from the precursor (E) is appropriately set as desired so as to effectively contribute to film formation.

When the film forming space is open and continuous with the reaction space, the internal pressure of the film forming space is the pressure introduced into the reaction space between the substrate-like raw material for forming the deposited film and the gaseous halogen oxidant. In relation to the flow rate, adjustment can be made by using, for example, differential exhaust or a large exhaust device.

Alternatively, if the conductance of the connection between the reaction space and the film-forming space is small, an appropriate exhaust system may be provided in the film-forming space.
By controlling the exhaust volume of the device, the pressure in the film forming space can be adjusted.

In addition, if the reaction space and film-forming space are integrated and the reaction position and film-forming position are only spatially different, use differential pumping as described above or use a large-scale pump with sufficient exhaust capacity. It is best to install an exhaust system.

As described above, the pressure in the film forming space is determined based on the relationship between the gaseous raw material introduced into one reaction space and the introduction pressure of the gaseous/\rogen oxidizing agent, and is preferably 0.0
01 Torr to 100 Torr, more preferably 0.0 Torr.
0ITorr ~ 307ro r r, optimally 0.0
It is desirable that the pressure be 5 to 10 Torr.

Regarding the original form of the gas, when introducing the raw material for forming the deposited film and the rogen-based oxidizing agent into the reaction space, these are mixed uniformly and efficiently, and the precursor (E) is efficiently mixed. The geometrical arrangement of the gas inlet, the substrate, and the gas outlet must be designed in consideration of the geometrical arrangement of the gas inlet, the substrate, and the gas outlet so that the gas can be generated and the film can be formed properly without any problems. One preferred example of this geometry is shown in FIG.

The substrate temperature (Ts) during film formation is set as desired depending on the type of gas used, the number of types of deposited film to be formed, and the required characteristics. The temperature of the substrate is preferably from room temperature to 450°C, more preferably from 50 to 400°C, especially when forming a crystalline deposited film with better electrical insulation. (Ts) is preferably 300 to 600°C.

As for the atmospheric temperature (Tat) in the film forming space.

The substrate temperature (TS) is adjusted such that the precursor (E) and the precursor (D) to be generated do not change into chemical species unsuitable for film formation, and the precursor (E) is efficiently generated. It can be determined as desired in relation to the above.

The substrate used in the present invention may be electrically conductive or electrically insulating, as long as it is appropriately selected depending on the intended use of the deposited film to be formed. Examples of the conductive substrate include:

NiCr, Steer L/S, A! L, Ci, Mo, Au
, Ir, Nb, Ta, V, Ti
, Pt, Pd, or alloys thereof.

As the electrically insulating substrate, films or sheets of synthetic resins such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, glass, ceramic, paper, etc. are usually used. Preferably, at least one surface of these electrically insulating substrates is subjected to conductive treatment, and another calendar is preferably provided on the conductive treated surface side.

For example, if it is glass, its surface is NiCr.

AfL, Cr, Mo, Au, Ir, Nb, Ta.

V, Ti, Pt, Pd, In2O3, 5n02゜ITO
(I n203+5n02), etc., or if it is a synthetic resin film such as polyester film, NiCr, Al, Ag, Pb,
Zn, Ni, Au, Cr, Mo, Ir, N'b, Ta
, V, Ti, Pt, etc. by vacuum evaporation, electron beam evaporation, sputtering, or the like, or by laminating with the metal, and the surface thereof is subjected to conductive treatment. The shape of the support may be any shape, such as a cylinder, a belt, or a plate, and the shape is determined as desired.

It is preferable to select the substrate from among the above in consideration of the adhesion and reactivity between the substrate and the film.Furthermore, if the difference in thermal expansion between the two is large, a large amount of distortion will occur in the film, resulting in a film that is of good quality. Therefore, it is preferable to select and use a substrate whose thermal expansion difference is close to that of the two substrates.

In addition, the surface condition of the substrate is directly related to the structure (orientation) of the film and the occurrence of cone-shaped structures, so it is important to treat the surface of the substrate so that it has a film structure and structure that provides the desired characteristics. is desirable.

FIG. 1 shows an example of an apparatus suitable for implementing the deposited film forming method of the present invention.

The deposited film forming apparatus shown in FIG. 1 is roughly divided into three parts: an apparatus main body, an exhaust system, and a gas supply system.

The main body of the device is provided with a wide space pumping and ui's space.

101 to 105 are cylinders filled with gas used for film formation, 101a to 105a are gas supply pipes, and 101b to 105b are mass flow controllers 5- for adjusting the flow rate of gas from each cylinder. ．． 101
c to 105c are gas pressure gauges, 101d to 105, respectively.
d and 101e to 105e are valves and 10
1f to 105f are pressure gauges each indicating the pressure within the corresponding gas cylinder.

106 is a container for containing a liquid or solid raw material, 106a, which has a heating device (not shown) used as needed;
, 106b is a gas supply pipe.

106C is a valve.

Reference numeral 120 denotes a vacuum chamber, which has a structure in which a pipe for introducing gas is provided at the upper part and a reaction space is formed downstream of the pipe.
It has a structure in which a film forming space is formed in which a substrate holder 112 is provided such that a substrate holder 18 is installed therein. The piping for gas introduction has a triple concentric arrangement structure, and the gas from the gas cylinder 101 and the raw material material from 106 are introduced from the inside, the gas introduction pipe 109 of $1, and the gas from the gas cylinder 102 is introduced. It has a second gas introduction pipe 110 and a third gas introduction pipe 111 into which gas from the gas cylinders 103 to 105 is introduced.

Each gas introduction tube is designed to discharge gas into the reaction space so that the inner tube is located further away from the surface of the substrate. That is, the gas introduction pipes are arranged so that the outer pipes surround the inner pipes.

Gas is supplied from the tube cylinder to each introduction pipe through gas supply pipelines 123 to 125, respectively.

Each gas introduction pipe, each gas supply pipeline, and the vacuum chamber 120 are evacuated via the main vacuum valve 119 by a vacuum evacuation device (not shown).

The base body 118 is installed at a desired distance from the position of each gas introduction pipe by moving the base body holder 112 up and down.

In the case of the present invention, the distance between the substrate and the gas outlet of the gas inlet pipe is determined appropriately by taking into consideration the type of deposited film to be formed, its desired characteristics, gas flow rate, internal pressure of the vacuum chamber, etc. It can be determined as desired, but preferably several mm to 2
It is desirable that the length be 0 cm, more preferably about 5 mm to 15 cm.

Reference numeral 113 denotes a substrate heating device for heating the substrate 118 to an appropriate temperature during film formation, or for preheating the substrate 118 before film formation, or for heating the film for 7 anneals after film formation. It's a heater.

The heater 113 for heating the substrate is connected to the power source 1 through a conductor 114.
Power is supplied by 15.

A thermocouple 116 is used to measure the substrate temperature (Ts) and is electrically connected to the temperature display bag a117.

Hereinafter, the present invention will be specifically explained according to Examples.

Example 1 Using the film forming apparatus shown in FIG. 1, a deposited film was produced by the method of the invention as follows.

The He gas filled in the pump 101 was supplied at a flow rate of 10 s.
Raw material container 10 containing Ai (CH3)3 at c cm
6 and bubble it to H from the gas introduction pipe 109.
A1(CH3)3 vaporized at about o, ootmol/min together with e-gas is added to the H gas filled in the pump 102.
Flow the e-gas! At 5 s e cm, the F2 gas filled in the pump 103 was pumped at a flow rate of 10105e,
04 was introduced into the vacuum chamber 102 from the gas introduction pipe 111 at a flow rate of 10105e.

At this time, the pressure inside the vacuum chamber 120 was adjusted to 0.6 Torr by adjusting the opening/closing degree of the vacuum valve 119. Using quartz glass (15 cm x 15 cm) on which molybdenum was sputter-deposited in advance on the base, the mixing area of AfL(CH3)3 gas, No gas and F2 gas between the gas inlet itt and the base, and the red-purple color at e o o 'c. Luminescence was seen. The substrate temperature (Ts) was set at 300°C.

When gas is flowed in this state for 3 hours, the film thickness A as shown in Table 1 is obtained.
An O:O:F film was deposited on the substrate.

Furthermore, the unevenness in film thickness distribution was within ±5%.

The deposited A:0:F film has a substrate temperature of 30,000 and 6
At 00°C, it was confirmed by electron beam diffraction that it was amorphous and crystalline.

Several humanoid electrodes with a diameter of 1 mm were deposited on the surface of each sample, and the specific resistance between them and a molybdenum electrode deposited on quartz glass was measured. The film formation and results are shown in Table 1 under Example 1.

Examples 2 to 5 In the device used in Example 1, A sentence (CH3) 2 and N
Using CHa as a raw material gas instead of O, the C:F film is
6 and NH3 are used as raw material gas.
Tables 1 and 2 show the results of creating a Zr:C:F film using Zr(OC3H7)4 and CHa as source gases.

〔effect〕

From the detailed description and each example of 1: Deposition 1 of the present invention
According to the 112 formation method, the same 11
In addition, membrane quality can be easily controlled and a membrane with uniform physical properties can be obtained over a large area. Also, productivity, 1. Excellent productivity,
High quality insulation 11!2 with excellent characteristics can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a film forming apparatus used in an example of the present invention. 101-105------------Gas cylinder,
101a-106a, 106b -1---1----Gas introduction pipe, 101b-
106b, 108ob ---------- Mass flow meter, 101
c -105c------Gas pressure gauge, 101d
-105d and 101e to 105e, 106cm----bulb. 101f~l O8f----------------------
mm force meter. 109 , 110 , 111 ------- Gas tube for 4 people 112 ------------- (Body holder, 113 ---------- --------Heater for heating one substrate. 116---------Thermocouple for monitoring substrate temperature, 118-11------JX body, 1
19--------------- one vacuum exhaust valve;
128 to 11----------A heater for raw material vaporization, and 129 to 11--A heater for IF to prevent material accumulation, respectively. There is.

Claims (11)

[Claims] (1) Introducing into the reaction space a raw material containing Al, C, B, or Zr that can be made into a gas for forming a deposited film, and a gaseous halogen-based oxidant having the property of oxidizing the raw material. chemically generating a plurality of precursors including excited state precursors by contacting them, and using at least one of the precursors as a source of a deposited film component within the deposition space. A deposited film forming method characterized by forming an electrically insulating film on a substrate. (2) The deposited film forming method according to claim 1, wherein the raw material containing Al, C, B, or Zr that can be made into a gaseous state is an organometallic compound. (3) The deposited film forming method according to claim 1, wherein the raw material containing Al, C, B, or Zr that can be made into a gaseous state is a hydride. (4) The deposited film forming method according to claim 1, wherein the raw material containing Al, C, B, or Zr that can be made into a gaseous state is a halide. (5) The deposited film forming method according to claim 1, wherein the gaseous halogen-based oxidizing agent contains halogen gas. (6) The deposited film forming method according to claim 1, wherein the gaseous halogen-based oxidizing agent contains fluorine gas. (7) The deposited film forming method according to claim 1, wherein the gaseous halogen-based oxidizing agent contains chlorine gas. (8) The deposited film forming method according to claim 1, wherein the gaseous halogen-based oxidizing agent is a gas containing fluorine atoms as a constituent component. (9) The deposited film forming method according to claim 1, wherein the gaseous halogen-based oxidizing agent contains halogen in a nascent state. (10) The deposition according to claim 1, wherein the substrate is disposed at a position opposite to the direction in which the gaseous raw material and the gaseous halogen-based oxidizing agent are introduced into the reaction space. Film formation method. (11) The deposited film forming method according to claim 1, wherein the gaseous raw material and the gaseous halogen-based oxidizing agent are introduced into the reaction space from a transport pipe having a multi-tube structure.