JPS61256588A - Electric field light emitting element and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to electroluminescent films (electroluminescent elements) used for flat panel displays, various light sources, and lighting.
(hereinafter referred to as "rEL element") and its manufacturing method.

[Prior art]

EL devices that emit light (by applying an electric field to a solid film) are expected to be used as display devices to compete with CRTs because they can be made thinner and lighter, do not flicker, and can be driven at low voltages. has been done.

However, until now, the luminous efficiency of EL elements was as low as 1.

Sufficient luminance is not obtained. The reason for this is thought to be that the crystallinity of the first light-emitting layer is poor, electrons are scattered by impurities, and sufficient excitation is not achieved.

In a conventionally known method for manufacturing an EL element.

The deposition method for the electroluminescent film (hereinafter referred to as rEL luminescent film) includes vapor deposition, CVD, MOCVD, sputtering, ALE (atomic layer epitaxy), etc. Generally, A plasma CVD method is used.

The reaction process in forming a deposited film by the conventional plasma CVD method is the conventional so-called thermal carbon
It is much more complicated than the VD method, and there are many points about the reaction mechanism that are unclear.

In addition, there are many formation parameters for the deposited film, such as C example, t example,
Plasma becomes unstable at 1:00 because it depends on a combination of many parameters (substrate temperature, flow rate and ratio of introduced gas, pressure during formation, high frequency power, electrode structure 2 reaction vessel structure, pumping speed, plasma generation method, etc.) Under such conditions, the formed deposited film was often adversely affected. Furthermore, device-specific parameters must be selected for each device, making it difficult to generalize manufacturing conditions.

However, depending on the application of the salt 8j 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 using the D method requires a large amount of equipment investment for mass production equipment), the management items for mass production are also complicated, and the control tolerance is narrow), and equipment adjustments are delicate. 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 ordinary 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.

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.

[Purpose of the invention]

The present invention eliminates the above-mentioned conventional drawbacks, and at the same time provides a novel EL element and its manufacturing method that do not rely on conventional manufacturing methods.

An object of the present invention is to provide an EL phosphor with improved luminance and lifetime compared to conventional EL devices.

Another object of the present invention is to be able to easily control the characteristics of the EL film to be formed, maintain all of its good characteristics, and improve the original brightness, lifetime, and deposition rate under manufacturing conditions. An object of the present invention is to provide a method for manufacturing an EL element that can simplify management and easily achieve mass production.

[Summary of disclosure]

The electroluminescent device of the present invention is:

The following general formulas (A) and (B) are placed in the film forming space.

Compounds (A) and (B) represented by (C).

It is characterized by having an electroluminescent film formed by introducing active species that chemically react with (C) and at least one of the compounds (A), (B3, and (C)).

MmRn・・・・・・・・・・・・・・・・・・
(A) AaBb・・・・・・・・・・・・・・・
・・・(B)JjQq・・・・・・・・・・・・・・・
......(C) (However, 1m 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, 1M is a zinc (Zn) element, R is hydrogen (H),
No. 10 Gen (X) and Hydrocarbon Fund are shown 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 sulfur (S) or selenium (Se) element, B is hydrogen (H),
Each represents a halogen (X) and a hydrocarbon group.

D is a positive integer equal to or an integral multiple of the valence of Q.

q is a positive integer equal to or an integral multiple of the valence of J, J is manganese (Mn) or a rare earth metal element, Q is hydrogen (H),
Each represents a halogen (X) and a hydrocarbon group. ) Furthermore, in the method for manufacturing an electroluminescent device of the present invention, the following general formula [A
), (B), (C) Compounds (A), (B)
, (C) and the compound (A).

By introducing active species that chemically react with at least one of (B) and (C).

The present invention is characterized in that a 1 c% field source film is formed on the substrate.

MmRn・・・・・・・・・・・・・・・・・・
(A) AaBb・・・・・・・・・・・・・・・
・・・(B)JjQq・・・・・・・・・・・・・・・
......(C) (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 zinc (Zn) The element R is hydrogen (H).

Halogen (X) and hydrocarbon funds are shown 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 sulfur (S)
or selenium (Ss) element, B represents water (H), halogen (X), and hydrocarbon base, respectively.

j is a positive integer equal to or an integral multiple of the valence of Q.

q is a positive integer equal to or an integral multiple of the valence of J, J is manganese (Mn) or a rare earth metal element, Q is hydrogen (H),
Each represents a halogen (X) and a hydrocarbon group. ) [Example] Next, the present invention will be explained by giving a typical example of an EL element manufactured by the manufacturing method of the present invention.

FIG. 1 is a cross-sectional view of a typical EL device obtained by the present invention. In Figure 1, IIfi glass substrate is used, and 2 is tin (Sn) doped indium oxide (iT).
3 is a transparent electrode such as O).

Y! Insulator layer such as Os, 4 is EL source layer, 5 is Y
! 01 is an insulating layer, and 6 is an electrode such as A1.

The EL light emitter layer 4 is made of ZnS or Zn5e with Mn, Pr,
Sm, Eu, Tb, Dy, Ha, Er, Tm
, containing rare earth elements such as Nd and fluorides of these rare earth elements.

In the method of the present invention, when forming a film as a desired EL emitter layer, the film formation parameters are set by introducing the compounds represented by the general formulas (A), (B), > and (C), respectively. The amount of introduced active species that chemically reacts with at least one of (A), (B), (C) and these compounds, the temperature in the substrate and the film forming space, the internal pressure in the film forming space, Therefore, the film forming conditions can be easily controlled, and a film as an EL light emitting layer can be formed with reproducibility and mass production.

The "active species" referred to in the present invention is the above-mentioned compound (A).

At least one of compound (B) and compound (C)
For example, the above compound (A),
(B) and (C) are given energy, and the compound (A) is chemically reacted with at least one of (B) and (C).
A substance that plays a role in bringing A), (B), and (C) into a state in which a deposited film can be formed. Therefore, the "active species" may include constituent elements constituting the deposited film to be formed, or may not include such constituent elements.

The general formula (A) used in the present invention.

Compounds (A) and (B) represented by (B) and (C), respectively
and (C), a chemical that causes molecular collision with the active species to cause a chemical reaction in the space where the substrate on which the film is to be formed exists, and contributes to the formation of the deposited film formed on the substrate. Although it is more desirable to select at-spontaneously generated species, in its normal state of existence, the above-mentioned active species is inactive, or if it is not so active. is compound (A), (B) and (C).
).

(B) and (C) are the general formulas (A) (B) and (C)
Excitation energy strong enough to prevent complete dissociation of M, A and J' in the compound (A) is applied before or during the gold film formation.
, (B) and (C) are brought into an excited state where they can chemically react with the active species).

Further, a compound that can be brought into such an excited state is employed as compounds (A), (B), and (C) 1ai 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, the compounds (A) RnMm, compound (B) AaBb, and compound (C) JjQ (l), which are compounded by the general formulas (A) and (B), are effectively used as follows. Compounds can be mentioned.

That is, "M" is a Zn element, and "A" is S or Se.
Element, "J" as Mns P rs Sm, Eus
Tb*D )'s Ho, Er, Tm, compound k containing Nd elements Compounds (A), (B) and (
This can be cited as C).

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

As an unsaturated hydrocarbon group, the carbon-carbon bond is not only one type of bond, but also one having at least two types of bonds among - double bond, double bond, and triple bond. Any method can be effectively adopted as long as it meets the purpose of the invention.

Further, in the case of an unsaturated hydrocarbon group in which all double bonds are plural, there is no problem whether the double bond is a non-integrated double bond or an integrated double bond.

Examples of acyclic hydrocarbon groups include alkyl groups, alkenyl groups,
Alkynyl group, alkylidene group, alkenylidene group, alkynylidene group, alkylidine group.

Preferable examples include alkenylidine groups and alkynylidine groups, and in particular, the number of carbon atoms is preferably 1-10. It is preferable to have 1 to 7 carbon atoms, most preferably 1 to 5 carbon atoms.

In the present invention, compounds (A), (
As B) and (C), those that are gaseous under standard conditions or that can be easily vaporized under the usage environment are selected.
” and the selection of rJJ and rQJ, as appropriate.

rRJ and [MJ, rAJ and rBJ and rJJ and rQJ
A selection of combinations is made.

In the present invention, a specific compound effectively used as compound (A) is s Z n Me 2 .

ZnEt, ZnX, etc. are effectively used as the compound (B), and specific examples include *Me, SsMe
, s e , E jts , E jts e etc. are specifically used as the compound (C), such as Me! Mns Me, Pr, Me, SmlMe, E
u, Me, Tb.

MemD7. Me, Ho 1Me, Er, Me, Tms
Me, Nd.

EttMns Et3PFl, EtsSm, Et3
Eu, EtsTb.

EtlD)' s Et3Ho s EtlEr,
Et, 'rm, Et, Nd.

PrX3s 5rnXs, EuX5s TbX5.
Dyx, HoXamErXas TmX5-Nd
Examples include X5.

In the above, X is a halogen CF, CJ, or 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 short in consideration of the reactivity with the compound (A) or/and (B) or/and (C,), ease of handling during film formation, and The longer the length, the better, considering all factors such as transportation to the film forming space. Furthermore, 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 so as to effectively obtain a film having the desired properties, taking production efficiency into consideration, and should have an appropriate lifetime in relation to other film forming conditions. Active species are appropriately selected and used.

Activity 8 [used in the present invention] is a compound (A) or/and (B) or/ in which an active species having a lifespan appropriately selected in view of all the above points is specifically used as its lifespan. The chemical affinity with (C) is appropriately selected depending on the user's needs, but preferably the lifespan is 1×10 in an environment within the compatible range of the present invention.
−″ seconds or more.

Preferably more than 1 x 1 o-' seconds, optimally l
It is desirable that the time is longer than X 10-'' seconds.

The active species used in the present invention acts as a so-called initiator when a chemical reaction with compound (A) or/and (B) or/and (C) occurs in a chain reaction. Since the amount introduced into the film-forming space may be sufficient to cause a chain reaction of chemical reactions efficiently, it is sufficient to ensure that the amount introduced into the film-forming space is sufficient.

The active species used in the present invention is introduced into the film forming space at the same time when forming the deposited film in the film forming space, and the active species is introduced into the film forming space to form the compound (A
), (B) and (C) or/and the excited species (A) of the compound (A), the excited a(B) of the compound (B) and the compound (C
) chemically interacts with the excited species (C). As a result, an EL luminescent film having desired characteristics can be easily formed on a desired substrate. According to the present invention, there is provided an atmosphere chamber for the film forming space.

By arbitrarily controlling the substrate temperature as desired.

A more stable CVD method can be achieved.

One of the differences between the method of the present invention and the conventional CVD method is that active species activated in advance in an [activation space] different from the film-forming space are used. This makes it possible to dramatically increase the deposition rate compared to the conventional CVD method.
In addition, it is now possible to further reduce the substrate temperature during film formation).

Therefore the quality is stable. ! EL light-emitting elements with optimized characteristics can be provided industrially in large quantities and at low cost.

In the present invention, the activated species generated in the activation space are discharged,
Rather than being activated by being excited by energy such as light, heat, or a combination thereof, it may be generated by contact with a catalyst or the like, or by addition.

In the present invention, a substance that is introduced into the activation space and generates hydrogen radicals as an active species generating substance or a substance that can be easily vaporized can be mentioned, and a specific l/c is H! ,D
Examples include t -HD and other rare gases such as *H, e +Ar.

In addition to the above, active species are generated by applying activation energy sounds such as heat, light, and discharge in the activation space, or by using catalytic sounds. This active strain is introduced into the gold film forming space. On this occasion.

It is necessary that the lifetime of the active species is desirably IXlO-' seconds or more, and having such a lifetime promotes an increase in deposition efficiency and deposition rate, and the compound ( Increases the efficiency of chemical reactions with A), (B) and (C).

Specifically, the activation energy that causes an activation effect on the active species generating substance in the activation space includes thermal energy such as resistance heating and infrared heating, light energy such as laser light, mercury lamp light, and halogen lamp light, and microscopic energy. wave,
It is possible to generate electrical energy such as t-S using RF, low frequency, DC discharge, etc., and these activation energies may act independently on the active species generating substance in the activation space, or , 2a or more may be used in combination.

Even when the compounds (A), compound (B), compound (C) and active species introduced into the film-forming space undergo a chemical reaction by mutual collision at the molecular level, an EL luminescent film is formed on the desired substrate. Although it is possible to select a substance capable of depositing all of the compounds (from those listed above), the above-mentioned When chemical reactivity is poor.

Alternatively, if a chemical reaction is to be carried out more effectively to efficiently generate a deposited film on a gas, compound (A), compound (B), compound (C) or/and active species may be added in the film forming space. It is also possible to use reaction promoting energy acting on the reaction space, such as the activation energy used in the activation space described above. Or, before introducing the compound (A), the compound (B), and the compound (C)'(r) into the film-forming space, in another activation space, the compound (A), the compound (B), and the compound (C) t- The entire excitation energy may be applied to bring it into an excited state.

In the present invention, the total amount of compound (A), compound (B), and compound (C) introduced into the film forming space and the proportion of active species introduced from the activation space (C) are determined by the film forming conditions, the compound (
A), the compound (B), the metal compound (C) and the type of active species,
It can be determined as desired depending on the desired characteristics of the film as an EL light emitting layer, but preferably 1000:l-1:1
0 (introduction flow rate ratio) is appropriate, preferably 500
:1 to 1:5 is desirable.

When the active species does not cause a chain chemical reaction with compound (A) or/and compound (B) or/and compound (C),
The ratio of the above introduced amounts is preferably 10:1 to 1:10.
．． ) The ratio is preferably 4:1 to 2:3. The internal pressure of the film-forming space during film-forming is as follows: Compound (A
), Compound (B), Compound (C), and the active species are appropriately determined according to the type and film forming conditions, etc., but are preferably 1Xl0"" to 5X10"pa, and preferably 5x1o-" to 1x1n. 3 pa, optimally 1X 10-' to 5xio''Pa.

Further, when it is necessary to heat the substrate during film formation, the substrate temperature is preferably 50 to 1000°C, more preferably 100 to 900°C, and most preferably 100 to 750°C.

Compound (A), compound (B), compound (C) in the film forming space
and how to introduce active species.

It may be introduced through a transport pipe connected to the film-forming space, or the transport pipe may be installed in the film-forming space and extended close to the film-forming surface of the substrate.

The tip may be introduced in the form of a nozzle, and the transport tube can be made full-duplex, with one side in the inner tube and one in the outer tube.For example, the active species can be introduced in the inner tube, and the compound ( A), compound (B), and compound (C) may be transported and introduced into the film forming space, respectively.

In addition, four nozzles connected to the transport pipe are prepared, and the tips of the four nozzles are placed near the surface of the substrate already installed in the entire film forming space, and each of the nozzles is placed near the surface of the substrate. The compound (A), compound (B), compound (C), and active species discharged from the nozzle may be introduced in a mixed manner. In this case, since it is possible to selectively form an EL luminescent film on the substrate, patterning and
This is convenient because it allows you to

Furthermore, as described above, the method of the present invention can be used not only for forming an EL light emitter film but also for forming an insulating layer and an electrode.

The present invention will be specifically explained below using examples.

[Example 1] The EL light emitting device shown in FIG. 1 was manufactured using the apparatus shown in FIG. 2 and the following operations.

In Figure 2, 200-1,200-2゜200-3
, 200-4 are the nozzles 2 (11-1°201-2.
20i-3 is a raw material gas introduction pipe, 202-1 is an active species raw material introduction pipe, 202-2 is an active species transport pipe, 203 is an activation chamber, 2o4 is a film forming chamber, 205 and 206 are activation means, 2o7 is a substrate support, 208 is a substrate, 209 is a heater for heating the substrate, 210 is pulp, and 211 is an exhaust device.

An ITO electrode 2 with a thickness of 200 OA was formed on the glass substrate 1 by sputtering, and a YTO electrode 2 with a thickness of 60 OA was formed on it by electron beam evaporation at a substrate temperature of 120°C.
,0. An insulator layer 3 was formed.

On top of that, H8 gas 200 is introduced into the activation chamber 203 made of a SCCMe quartz glass tube through the gas introduction pipe 202-1 in FIG. A 280 W microwave was applied to the activation chamber 203 to generate H radicals in the activation chamber 203.

The generated H radicals are transferred to the film forming chamber 2 through a nozzle 200-4 through a transport pipe 202-2 made of a quartz glass tube.
It was introduced in 2004.

At the same time, gas inlet pipe 201-1.201-2.20
He gas was bubbled through 1-3' (
CH,,)*Zn r (CH,), Se # (CH
), Mn at 5 mmol/min,
5mmol/min, 0.1mmol/min
Nozzles 200-1, 200-2, 20 in the ratio of n
0-3 into the film forming chamber 204.

In this case, (CHI)IZn* (CHI), , Se and (CH,), Mn are activated by the action of H radicals, undergo a chemical reaction, and are heated by the substrate heater 209 by about 40
Approximately 400O for 30 minutes on the substrate 208 heated to 0℃
A znSe (M21) emitter layer 4 was formed.

Further, on the light emitting layer 4, a Y, 0.0. An insulator layer 5 is formed thereon, and a thickness of 1000 is formed (by electron beam evaporation method).
An M electrode 6 of X was formed.

[Comparative example]

By high-frequency sputtering in an Ar gas atmosphere using a conventionally used znSe target containing Mn! Four UZnSe (Mn) luminescent layers were formed. Note that the other layers were formed in the same manner as in Example 1 to produce a %EL element without ζ.

The brightness-voltage characteristics were determined by applying a full sinusoidal voltage of 5 KHz between the transparent electrode 2 and the AI electrode 6 using the EL elements manufactured by the present invention and the conventional method shown in Example 1 and Comparative Example. Ta.

The results are shown in the t-m1 table.

From the results in Table 1, it is thought that the conventional method /I'iZnse (Mn) has poor crystallinity, scattering of electrons due to impurities, and insufficient excitation, resulting in an increase in the threshold voltage. In contrast, in the present invention, ZnSe (Mn) with good crystallinity was produced, and EL light emitting elements with low threshold voltage and high brightness were obtained.

[Example 2] (CHI) used in Example 1
(CH3)! set(CM,), Mn 0 instead of 1st
Compound (A) shown in the table.

An ELL optical device was produced in the same manner as in Example 1, except that Compound (B) and Compound (C)' were used as raw material gases for forming the luminescent layer, respectively, and the conditions listed in Table 2 were used.

A 5KiHz sine wave voltage was applied to these EL elements to determine their brightness-voltage characteristics. The threshold voltage and luminance at that time are shown in Table 2.

〔Effect of the invention〕

According to the present invention, it is possible to obtain an EL light emitting element that achieves the desired high brightness and low threshold voltage and has excellent voltage resistance and mechanical properties. Furthermore, according to the manufacturing method of the present invention,
In the formation of the film that becomes the EL light emitting layer, reproducibility is improved, film quality can be improved and film quality can be made uniform, and it is advantageous for increasing the area of the film, improving film productivity. Furthermore, it is possible to manufacture an EL light emitting device with a high yield of 1, which can be easily achieved in terms of mass production.

In addition, since it is possible to form a film at a low temperature, an EL element can be formed even on a substrate with poor heat resistance, and the process can be shortened by low-temperature treatment. Furthermore,
By controlling the amount of active species introduced,
The effect of being able to control the composition ratio and characteristics of the EL luminescent film is exhibited.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of an EL element produced according to the present invention, and the %wcz diagram is a schematic diagram of a manufacturing apparatus embodying the present invention. l...Substrate 2...Transparent electrode 3.5...Insulating layer 4...Light emitter layer 6...Electrode 200-1~ 4...Nozzles 20i-1 to 3...Introduction pipes 202-1 to 2...Transport pipe 203...Activation chamber 204... -Deposition chamber.

Claims (2)

[Claims] (1) In the film formation space, the following general formulas (A), (B), (C) are applied.
Formed by introducing the compounds (A), (B), (C) represented by and an active species that chemically reacts with at least one of the compounds (A), (B), (C). An electroluminescent device comprising an electroluminescent film. MmRn・・・・・・・・・・・・・・・・・・
(A) AaBb・・・・・・・・・・・・・・・・・・
(B) JjQq・・・・・・・・・・・・・・・・・・
(C) (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 a zinc (Zn) element, 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 sulfur (S)
Or selenium (Se) element, B is hydrogen (H), halogen (
X) and each represent a hydrocarbon group. j is a positive integer equal to or an integral multiple of the valence of Q, q is a positive integer equal to or an integral multiple of the valence of J, J is manganese (M
n) or a rare earth metal element, Q is hydrogen (H), halogen (
X) and each represent a hydrocarbon group. ) (2) In the method for manufacturing an electroluminescent device, a compound represented by the following general formulas (A), (B), and (C) (
A), (B), (C) and the compounds (A), (B), (
A method for manufacturing an electroluminescent device, comprising forming an electroluminescent film on the substrate by respectively introducing active species that chemically react with at least one of C). MmRn・・・・・・・・・・・・・・・・・・
(A) AaBb・・・・・・・・・・・・・・・・・・
(B) JjQq・・・・・・・・・・・・・・・・・・
(C) (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 a zinc (Zn) element, 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 sulfur (S)
Or selenium (Se) element, B is hydrogen (H), halogen (
X) and each represent a hydrocarbon group. j is a positive integer equal to or an integral multiple of the valence of Q, q is a positive integer equal to or an integral multiple of the valence of J, J is manganese (M
n) or a rare earth metal element, Q is hydrogen (H), halogen (
X) and each represent a hydrocarbon group. )