JPS61189630A - Formation of deposited film - Google Patents

Abstract

PURPOSE:To easily attain the simplification in control of film-forming conditions while contriving the increase of the deposition speed, by a method wherein two kinds of compounds expressed by respective specific formulas which are raw materials for forming deposited films and an activation halogen chemically reacting with at least one of them are introduced to the film-forming space to form a deposited film over a substrate. CONSTITUTION:Compounds expressed by formulas RnMm and AaBb are introduced to a film-forming chamber 104 through nozzles 100-1 and 100-2, respectively; where M and A are elements each belonging to the III and V groups of the periodic table; R and B hydrogen, halogen, or hydrogen carbide each; (m) and (a) positive integers equal to or integral multiples of the valence numbers of R and B, respectively; (n) and (b) positive integers equal to or integer multiples of the valance numbers of M and A, respectively). The raw material introduced to an activation chamber 103 and producing an activation seed with microwaves is preferably a gaseous or readily vaporizable substance, i.e. a substance which produces halogen radical, which is introduced through a nozzle 100-3 to the film-forming chamber 104.

Description

[Detailed Description of the Invention] [Prior Art] The present invention relates to non-quality or crystalline functional thin films such as semiconductor films, insulator films, and conductor films, especially active or passive semiconductor devices, optical The present invention relates to a method for forming deposited films useful for applications such as semiconductor devices, solar cells, and photosensitive devices for electrophotography.

Vacuum evaporation method, plasma CVD method, thermal CVD method, optical CVD method can be used to form the deposited film. 1. Reactive sputtering methods, ion blating methods, etc. have been tried, and in general, plasma CVD methods are widely used and commercialized.

Since the deposited films obtained by these deposited film formation methods are required to be applied to electronic devices and optoelectronic devices that require higher functionality, they have improved electrical and optical properties and fatigue due to repeated use. Characteristics or usage environment characteristics, and even uniformity.

There is room for further improvement in overall characteristics in terms of productivity and mass production, including 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. However, 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 1 reaction vessel structure, pumping speed, plasma generation method, etc.). Because it depends on a combination of many parameters.

At times, the plasma becomes unstable, which often has a significant negative effect on the deposited film. Furthermore, the actual situation is that parameters unique to each device must be selected 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.

According to Heigo et al., depending on the application of the deposited film, it is necessary to fully satisfy the requirements of large area, uniformity of film thickness, and uniformity of film quality, and mass production with reproducibility.
Forming a deposited film by the method requires a large amount of equipment investment for mass production equipment, the control items for mass production are complicated, the control tolerance is narrow, and the adjustment of the equipment is delicate. These have been pointed out as problems 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 a thin film of group 1-v compounds.

As mentioned above, in the formation of a monofunctional film, there is a strong desire to develop a method for forming a deposited film that can be mass-produced using low-cost equipment while ensuring practical characteristics and maintaining uniformity.

〔the purpose〕

The present invention eliminates the drawbacks of the conventional deposited film forming methods mentioned above, and at the same time provides a novel deposited film forming method that does not rely on conventional forming methods.

The purpose of the present invention is to be able to easily control the characteristics of a functional membrane;
A method for forming a deposited film that maintains at least the characteristics of a high-quality film obtained by conventional methods, improves the deposition rate, simplifies the management of film formation conditions, and facilitates mass production of films. The goal is to provide the following.

〔composition〕

In the deposited film forming method of the present invention, the following general formula (
A deposited film is formed on the substrate by introducing a compound (A) and a compound (B) represented by A) and (B), respectively, and an activated halogen that chemically reacts with at least one of the compounds. It is characterized by:

Rn M m ------=----(A)A a
B b ・・・・・・・・・・・・(B ) However, m is R
n is a positive integer equal to or an integral multiple of the valence of M, M is an element belonging to Group Ⅰ of the periodic table, R is hydrogen (H), halogen (X) each represents a hydrocarbon group.

a is a positive integer equal to or an integral multiple of the valence of B, or a positive integer equal to or an integral multiple of the valence of A, A is an element belonging to Group V of the periodic table, and B is hydrogen (H ), halogen (X),
The hydrocarbon groups are shown respectively.

In the method of the present invention, when forming a deposited film with desired functionality, the formation parameters of the deposited film are set such that the compound (A) represented by the general formulas (A) and (B), respectively, and (
B), and the amount of introduced active species that chemically reacts with at least one of these compounds, the temperature in the substrate and film-forming space, and the internal pressure in the film-forming space, and therefore, the deposited film formation can be easily controlled. Therefore, it is possible to form a functional deposited film with reproducibility and mass production.

The "active species" as used in the present invention refers to species that chemically interact with the compounds (A, ) and/or (B) to provide energy to the compounds (A) and/or (B). , chemically reacts with compound (A) or/and (B), and serves to make compound (A) or/and (B) into a state in which it can form a deposited film. .

Therefore, the "active species" may include constituent elements constituting the deposited film to be formed, or may not include such constituent elements.

The above general formulas (A) and (B) used in the present invention
Compounds (A) and (B) represented by each of these compounds are formed on the substrate by causing a chemical reaction by molecular collision with the above-mentioned active species in the space where the substrate on which the film is to be formed exists. It is more desirable to select a chemical species that spontaneously generates chemical species that contribute to the formation of a deposited film; If the activity is not that great, compounds (A) and (
In B), the compounds ('A ) and (B) have the general formula (A
) and (B) by applying excitation energy strong enough to not completely dissociate M and A in the compounds (A) and CB) before or during film formation to bring the compounds (A) and CB) into an excited state where they can chemically react with active species. In addition, a compound that can be brought into such an excited state is employed as one of the compounds (A) and (B) used in the method of the present invention.

In the present invention, a compound in the above-mentioned excited state will hereinafter be referred to as an "excited species".

In the present invention, compounds (A) RnMm and compounds (B) A, aB respectively represented by the general formulas (A) and (B) are used.
The following compounds can be mentioned as compounds that can be effectively used as b.

That is, an element belonging to group Ⅰ of the periodic table as r M J,
Specifically, B, AJI, Ga, In, Tu (7) elements belonging to group Ⅰ B, and "A" as elements belonging to group V of the periodic table, specifically N, P, As.

Compounds containing elements belonging to Group V B of Sb and Bi can be mentioned as compounds (A) and (B), respectively.

rRJ and rgJ are monovalent, divalent and trivalent hydrocarbon groups derived from linear and side chain saturated hydrocarbons and unsaturated hydrocarbons, or saturated or unsaturated monocyclic and Mention may be made of monovalent, divalent and trivalent hydrocarbon groups derived from polycyclic hydrocarbons.

Unsaturated hydrocarbon groups include not only a single type of carbon-carbon bond but also those having at least two types of bonds among - double bonds, double bonds, and triple bonds. If it is different from achieving the purpose of the invention, it can be effectively adopted.

Further, in the case of an unsaturated hydrocarbon group having a plurality of double bonds, it does not matter whether the double bonds are non-integrated double bonds or integrated double bonds.

Examples of acyclic hydrocarbon groups include alkyl groups and alkynyl groups (
, alkynyl group, alkylidene group, alkenylidene group,
Preferable examples include an alkynylidene group, an alkylidine group, an alkenylidine group, an alkynylidine group, and the number of carbon atoms is preferably 1 to 10.
More preferably carbon fi 1-7, optimally carbon number 1-5
Preferably.

In the present invention, the compounds (A) and (B) to be effectively used are selected from those that are gaseous under standard conditions or that can be easily vaporized under the usage environment.
In selecting "R" and "rMJ" and "A" and "rB" listed above, combinations of "R" and "M" and "rA" and r13J are selected as desired.

In the present invention, specific compounds effectively used as compound (A) include BMe3゜Au2 Me6
, G aMe3 , r nMe3 .

TIM e 3, B E t 3,
A n E t 6 .

GaE t3 , I nE t3 , T! QEt3
, BX3.

Specific examples of B2H6, Ga2H6, etc. that can be effectively used as the compound (B) include M 83 N
, M 83 P , M e 3 A S , M
e3Sb.

Me3 Bi , Et, 3 N, Et3 P, E
t3 As.

Et3Sb, Et3Bi, NX3, PX3.

AsX3, NH3, PH3, AsH3, SbH
I can name 3rd place.

In the above, X is halogen CF, C1°Br, I),
Me represents a methyl group, and Et represents an ethyl group.

The lifetime of the active species used in the present invention is preferably shorter in consideration of reactivity with compound (A) and/or (B), ease of handling during film formation, transportation to the film formation space, etc. In consideration of this, the longer the better, and the lifetime of the active species also depends on the internal pressure of the film forming space.

Therefore, the active species used should be selected and determined in such a way that a functional film with the desired properties can be effectively obtained, taking production efficiency into account. An active species having the following properties is appropriately selected and used.

The active species used in the present invention has a lifetime of:
The active species having a lifespan appropriately selected in view of the above points is appropriately selected as desired from within the compatible range of chemical affinity with the compound (A) and/or (B) to be specifically used. However, preferably, its lifespan is 1X10' seconds or more, more preferably IX10-3 seconds or more, optimally IX10' seconds or more under an environment within the scope of the present invention.
``It is preferable that it be on the abstract.

The active species used in the present invention can minimize its function as a so-called initiator when a chemical reaction with compound (A) or/and (B) occurs in a chain reaction. The amount introduced into the film forming space may be such that a chemical reaction can occur efficiently in a chain reaction.

The active species used in the present invention are simultaneously introduced into the film forming space (A) when forming a deposited film in the film forming space (A),
The compound (A) and (B) or/and the compound (A)G containing a component that will be the main component of the deposited film to be formed
excited species (A) or/and excited species CB of compound (B))
chemically interacts with As a result, an IN-V group compound deposited film having a desired functional acid can be easily formed on a desired substrate.

According to the present invention, a more stable CVD method can be achieved by arbitrarily controlling the ambient temperature and substrate temperature of the film forming space (A) as desired.

One of the differences between the method of the present invention and the conventional CVD method is that the activation space (C) is different from the film forming space (A).
] The method is to use active species activated in ]. As a result, the deposition rate can be dramatically increased compared to the conventional CVD method, and in addition, the substrate temperature during deposition film formation can be further lowered, allowing stable and controlled film quality. Deposited films having specific film properties can be provided industrially in large quantities at low cost.

In the present invention, the active species generated in the activation space (C) are not only excited and activated by energy such as electric discharge, light, heat, etc., or a combination thereof, but also by contact with a catalyst, etc., or by addition. It may be generated by

In the present invention, the raw material introduced into the activation space (C) to generate active species is preferably a gaseous or easily vaporizable substance, and can include a substance that generates \rogen radicals. , specifically F2 + C1
2*Brz+I2 rogen gas or BrF,
CIF, ClF3, ClF5.

BrF, , BrF3 , IF, , IF5 , ICI
.

Ru.

In addition to the above, heat and light are applied in the activation space (C).

Activated species are generated by applying activation energy such as electric discharge. This active species is introduced into the film forming space (A). At this time, the lifespan of the active species is preferably I x 10
= seconds, and having such a lifetime promotes an increase in deposition efficiency and deposition rate, and increases the efficiency of the chemical reaction with the compound (A) introduced into the film forming space (A). increase.

Specifically, the activation energy that causes an activation effect on the active species generating substance in the activation space (C) includes thermal energy such as resistance heating, infrared heating, scissor light, mercury lamp light, and halogen lamp light. Examples include light energy such as microwaves, RF, low frequency, electrical energy using discharge such as DC, etc., and these activation energies can be used alone to generate active species generating substances in the activation space (C). Compound (A) introduced into the film forming space (A), which may be allowed to act or may be made to act in combination of two or more types.
, ``Compound CB)'' and the active species are selected from those listed above, which can cause a chemical reaction by mutual collision at the molecular level even as they are, and can deposit a functional film on the desired gas. Although it is possible to
Depending on the selection of the compound (A), the compound (B), and the active species, the chemical reactivity described above may be poor, or the chemical reaction may be carried out more effectively to efficiently form a deposited film on the gas. In this case, in the film forming space (A),
Reaction promoting energy acting on the compound (A), the compound (B) or/and the active species, such as the above-mentioned activation space (C)
There is no problem in using the activation energy used in . Or, before introducing the compound (A) and the compound (B) into the film forming space (A), place the compound (A) and the compound (B) in another activation space (B).
In this step, excitation energy may be applied to bring the compound (A) and compound (B) into the above-mentioned excited state.

In the present invention, the compound (A) introduced into the film forming space (A)
), the ratio of the total amount of compound (B) and the amount of active species introduced from the activation space (C) depends on the deposition conditions, the types of compound (A), compound (B), and active species, and the desired function. It can be determined as desired depending on the characteristics of the gambling film, etc., but is preferably 1.
000:1 to 1:10 (introduction flow rate ratio) is appropriate, and more preferably 500:1 to 1:5.

If the active species does not cause a chain chemical reaction with compound (A) or/and compound (B), the above introduction amount ratio is
Preferably lo:1-1:10°, more preferably 4:1
The internal pressure of the film formation space (A) during film formation, which is preferably 2:3, is the ratio of compound (A) to compound (B).
It is determined appropriately according to the selected type of active species and deposition conditions, etc., but preferably I x 10-2 to 5xt
oiPa, more preferably 5X10-2 to lX103P
a. The optimum temperature is preferably 1 x 10-1 to 5 x 10 Pa, and if it is necessary to heat the substrate during film formation, the substrate temperature is preferably 50 to 1000°.
C1 is more preferably 100 to 900°C, optimally 100°C
It is desirable that the temperature be 750°C.

The compound (A), the compound (B), and the active species may be introduced into the film forming space (A) through a transport pipe connected to the film forming space (A); Alternatively, the transport pipe may be installed in the film forming space (A) and extended to near the film forming surface of the substrate, and the tip may be introduced with a nozzle shape, or the transport pipe may be doubled. one side with the inner tube,
The other may be transported into the film forming space (A) using the outer pipe, for example, the active species may be transported using the inner pipe, and the compound (A) and the compound (B) may be transported using the outer pipe.

In addition, three wooden nozzles connected to the transport pipe are prepared, and the tips of the three wooden nozzles are placed near the surface of the substrate already installed in the film forming space (A). Compound (A) and compound (B) discharged from respective nozzles in
) and active species are mixed, which is convenient because patterning can be performed simultaneously with film formation.

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

Example 1 200 SCC of F2 gas was supplied from the gas introduction pipe 102 in Fig. 1.
M is introduced into an activation chamber 103 made of a quartz glass tube, and a 300 W microwave is applied to the activation chamber 103 from a waveguide placed above the activation chamber 103 as an activation source 5 to activate it. 0 that generated F radicals in the chemical chamber 103
The generated F radicals are transferred to the film forming chamber 1 from a nozzle 100-3 via a transport pipe 102-2 made of a quartz glass tube.
It was introduced in 2004.

At the same time, 10 mm of (CH3)2Ga was bubbled with He gas through the gas introduction pipe 101-2.
From the nozzle Zoo-2 at a rate of l/min to the film forming chamber 104
was introduced in. On the other hand, AsH3 gas was introduced into the film forming chamber 104 from the nozzle 100-10 at a rate of 10 mmal/win through the gas introduction pipe 1, 01-1. In this case (CH3) 2Ga and AsH3 are activated by the action of H radicals to decompose Ga and As, respectively, and are placed on a quartz substrate 108 heated to about 320°C by a substrate heater 109 for 1.5 hours. 30 cm x 30 c
G a A s @ with a film thickness of approximately 1.2 gm over an area of +a
was formed.

When the film properties of this GaAs film were evaluated, it was confirmed that there was no unevenness in film thickness, and that the film was of good quality with almost no dependence on semiconductor properties depending on location.

Example 2 In Example 1, the raw material gases shown in Table 1 were used instead of (CH3)2Ga and AsH3 to form compound (A) and compound (
B), and the amounts of compound (A) and compound (B) introduced were each 1 mmal/l1 inch, and the film was formed in substantially the same manner as in the example except for the conditions listed in Table 1. A thin film shown in Table 1 was formed.

When the film properties of these thin films were evaluated, it was confirmed that they were uniform in thickness, uniform, and of good quality.

Example 3 In Example 1, R installed around the film forming chamber 104
A power of 3 W at a high frequency of 13.56 MHz was applied to the film forming chamber 104 using the F discharge device 106 to form a plasma atmosphere in the reaction chamber 104 . In this case, the base 106 was placed at a position 1CI11 on the downstream side of the plasma atmosphere so as not to directly touch the plasma atmosphere. Approximately 2g in 1 hour after starting film formation
A GaAs film with a thickness of m was formed. The substrate temperature at this time is 3
The temperature was kept at 00°C. Except for the above, the process was carried out in the same manner as in Example 1. When the film characteristics of this GaAs film were evaluated in the same manner as in Example 1, it was confirmed that the film was of good quality.

Furthermore, the film was mechanically excellent without peeling from the substrate.

Example 4 A GaAs film was produced in the same manner as in Example 1 except that C12 gas was used instead of F2 gas in Example 1. It was confirmed that the film properties of this GaAs film were also good.

〔Effect of the invention〕

According to the deposited film forming method of the present invention, the desired electrical, optical, photoconductive, and mechanical properties of the formed film are uniform, and the reproducibility in film formation is improved. In addition to making it possible to improve the film quality and make the film uniform, it is also advantageous for increasing the area of the film, and it is possible to improve the productivity of the film and easily achieve mass production.

Furthermore, since it is possible to form a film at low temperatures, it is possible to form a film even on substrates with poor heat resistance, and the process can be shortened by low-temperature processing. The effect is that the composition ratio and properties of the film can be controlled.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a manufacturing apparatus that embodies the method of the present invention. i o t----4 Immigration. 102--, -1 transport pipe, 103--1 activation chamber, 104--1 film forming chamber.

Claims (1)

[Claims] A compound (A) and a compound represented by the following general formulas (A) and (B), respectively, which are raw materials for forming a deposited film, are placed in a film forming space for forming a deposited film on a substrate. (B) and an activated halogen that chemically reacts with at least one of these compounds to form a deposited film on the substrate. RnMm・・・・・・・・・(A) AaBb・・・・・・・・・(B) However, m is a positive integer equal to or an integral multiple of the valence of R, n
is a positive integer equal to or an integral multiple of the valence of M, M is an element belonging to Group III of the periodic table, and R represents hydrogen (H), halogen (X), or a hydrocarbon group, respectively. a is a positive integer equal to or an integral multiple of the valence of B, b is a positive integer equal to or an integral multiple of the valence of A, A is an element belonging to Group V of the periodic table, B is hydrogen (H ), halogen (X),
The hydrocarbon groups are shown respectively.