JPH03165492A - Method and device for manufacturing semiconductor device - Google Patents

Abstract

PURPOSE:To provide an EL element of a high luminance brightness and a high efficiency by forming the light emitting matrix of a thin film EL element by a physical deposition process and independently supplying light emitting ions with more than one kinds of organic compounds as supply sources of the light emitting ions. CONSTITUTION:A light emitting layer matrix is formed by physical deposition process used in forming EL light emitting layers. An EL emitting layer is formed by evaporating more than one organic compounds in the light emitting center and independently supplying them. As the deposition process, any physical deposition process including the resistance wire heated deposition process, EB process, SP process, molecular beam epitaxy process, ion plating process, and others may be used. As the organic metallic compound, any such compound of the temperature for obtaining a vapor pressure higher than 10<34>Pa is lower than the decomposition temperature, preferably a compound having a softening temperature lower than that of glass (about 600 deg.C) may be used. The compound meeting the conditions described above and not containing oxygen, may be chosen out of the compounds in the forms of (C5H5)3X, (CH3C5H4)3X (where X denotes Ce, Eu, Tb, Sm, Tm, Er, Pr, Dy or Ho), (C5H5)2Mn, and (CH3C5H4)2Mn.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a semiconductor device for providing an arbitrary luminescent color;
In particular, it relates to thin film electroluminescent devices.

[Prior Art] Conventionally, the methods used to form the light-emitting layer of thin-film EL devices include resistance wire heating evaporation, ion blating, and especially electron beam evaporation (hereinafter referred to as EB). ) method or sputtering (hereinafter referred to as SP) method.

In these physical vapor deposition methods, a light-emitting layer matrix typified by ZnS and a transition metal such as Mn or a rare earth element (Ce) are used.

E u + T b * S m r T rn +
E r * P r + D y or Ho), etc. are used as the luminescent center, and these are mixed and stirred at an appropriate mixing ratio, molded into an arbitrary shape, and fired, and the powder is used as an evaporation source. Therefore, not only ZnS but also CaS, SrS, etc. can be easily made into thin films, and various luminous colors can be obtained. In a thin film formed by such a manufacturing method, differences in vapor pressure characteristics between the host material of the luminescent layer and the luminescent center material cause uneven evaporation rates of each, resulting in uneven concentration or clusters of luminescent centers in the luminescent layer. It is known to cause a decrease in brightness.

Regarding the problem of ZnS:Mn films formed by the EB method, see Journal Applied Coijinx No. 53.
Volume 6 (1982), pages 4146 to 4151 (J
, App 1. Phys, 53 (1982) 4146-
4151. ) is discussed.

Regarding ZnS:Tb,F films, see Proceedings of the Third International Display Research Conference, Kobe, 1983, pp. 84 to 87 (Proceedj, ngsof).
the3rd 1international disp
lay research conference 84
-87 (1,983) Kobe).

[Problems to be Solved by the Invention] In the above-mentioned conventional technology, sufficient consideration was not given to the point of adding luminescent centers independently and in a well-distributed manner.

When forming a thin film using one evaporation source containing different compounds, two or three luminescent centers may be formed during the formation process of one luminescent layer or within a layer due to sublimation or differences in vapor pressure characteristics of the constituent molecules.
Form molecules and even clusters. As a result, clusters that act as non-radiative centers or energy deactivation centers are present in the thin film, resulting in problems such as a decrease in excitation efficiency and luminous efficiency of the thin film EL device.

The present invention aims to provide a technique for uniformly adding luminescent centers to a light emitting layer, and further aims to realize a thin film EL element with high brightness and high efficiency.

Another object of the present invention is to provide a semiconductor manufacturing apparatus that can uniformly add luminescent centers.

[Means for Solving Problem A] In order to achieve the above object of the present invention, technical means applied to the light emitting layer of the semiconductor light emitting device, particularly the thin film EL device, of the present invention will be described.

In order to uniformly add the luminescent centers in the luminescent layer, it is effective to control and supply the luminescent centers independently. For example, Z
nS: When forming a Mn thin film, by preparing evaporation sources for ZnS and Mn compounds and independently controlling the input power to the evaporation sources, the Mn thin film can be formed on the substrate in the depth direction.
A ZnS:Mn film with uniform p degree can be formed. However, Mn, which is the luminescent center, easily becomes molecules or clusters. Therefore, the Mn compound used as the evaporation source needs to be a compound that has little interaction between MnyK molecules in space or on the substrate and can maintain an appropriate distance.
Organic Mn compounds are considered suitable for this purpose. The above method can be applied to all combinations of EL light-emitting layers and light-emitting centers, and it is considered effective to use the above-mentioned organic compounds for doping one light-emitting center.

Therefore, in order to achieve the above objective, a light emitting layer matrix is formed by the physical vapor deposition method conventionally used for forming an EL light emitting layer, and at the same time, one or more kinds of organic compounds having a luminescence center are vaporized and supplied independently. We proposed a method to form a light-emitting film.

As the vapor deposition method, any physical vapor deposition method such as resistance wire heating vapor deposition method, EB, SP method, molecular beam epitaxy method, or ion blating method can be used.

As the organometallic compound, any compound whose temperature at which a vapor pressure of 10"Pa or more is obtained is lower than the decomposition temperature, preferably a compound whose decomposition temperature is lower than the softening point of glass (approximately 600°C) can be used. The following compounds can be considered as organic compounds that meet the requirements.

Compounds that satisfy the above conditions and do not contain oxygen include (C5H5)2X, (CH,C5H5)2X (where X is Ce, Eu, Tb, Sm, or Tm.

Er! (represents P r + D y or HO)
, (C5H,).

There are compounds selected from the group consisting of Mn, (CH3C,H4), and Mn.

(cs
Hs)z X M, (where X is Ce + E
u, T b + Sm, Tmy Er, Pr, Dy
or HO, or M is F + CI + B r
or I).

Also, (R1R2C3HO,)3X (here, X is Ce
.

Eu, Tb, Sm, Tm, Er, Pr, Dy or H
O, and R1 and R2 are CH3, C(CH,).

or CF) can also be used.

The light-emitting layer host material is not limited to II-Vl compounds,
Any phosphor matrix can be used.

In order to carry out the above method for manufacturing a semiconductor device, at least one supply port for an organometallic compound was provided in a physical vapor deposition container of a semiconductor manufacturing apparatus.

In addition, to achieve the above object, R, X (or S, Se or Te, or R).

At least one compound is selected from 1 (representing , CH, or C, H) and supplied simultaneously.

In order to implement the above method, at least one supply port for the compound R2X (where X represents S, Se, or Te, and R represents H, CH, or C2H) is provided in the semiconductor manufacturing equipment. Established. In addition, when an oxide phosphor is used as a light emitting layer, oxygen can also be introduced.

[effect] According to the method for manufacturing a semiconductor device according to the present invention.

In order to prepare the luminescent base material and the evaporation source of the luminescent center,
For example, ZnS and the like can be used in the manufacturing process with higher purity, and the evaporation rate can be stably controlled, and a high-quality film can be obtained by applying only the optimal sublimation energy to ZnS. Furthermore, since the doping of the luminescent centers can be controlled independently, a thin film with a uniform luminescent center concentration can be formed and the concentration in the film can be easily changed. Luminescent ions are introduced as large molecules and decomposed by the surface energy of the substrate, so ZnS
The formation of non-radiative centers caused by clustering of light-emitting ions can be suppressed due to the steric hindrance of the molecules even before they reach the substrate, making it possible to easily substitute them in the lattice positions of E.
L cords are obtained.

[Example] Next, embodiments of the present invention will be described with reference to the drawings.

(First Example) In the first example, an electron beam evaporation method is used to use ZnS as a deposition source and a hydrogen carrier gas as a luminescent-centered raw material (CH, C,
H, ), Mn (abbreviated as BCPM), Zn
A S:Mn thin film was formed.

FIG. 1 is a diagram showing a manufacturing apparatus in an embodiment of the method for manufacturing a semiconductor device according to the present invention. Inside the vacuum container 10 having a vacuum evacuation pump (not shown), electron beam evaporation@1
1. A substrate holder 12 having a heater for heating the substrate, a nozzle 13 for introducing a gas raw material, and a gas nozzle 14 for introducing a reactive gas such as hydrogen sulfide are installed. The luminescence center raw material is introduced from the temperature-controlled raw material cylinder 15 by a carrier gas whose flow rate is controlled. The reactive gas is introduced with direct flow control.

FIG. 2 shows the structure of a thin film EL device using a ZnS:Mn thin film formed according to the present invention. What is the element structure?

T a 20H/S i Ox is formed on the glass substrate 20 via a transparent Mm 21 of indium tin oxide (ITO).
First dielectric layer 221 of the laminated film ZnS2M according to the present invention
It is composed of an n-film light emitting layer 23, a second dielectric film 24, and an Al upper electrode 25. The thin gold film has an IQ of about 2 μm.

The light emitting layer 23 of ZnS:Mn film was formed by the following procedure. Glass substrate 2 formed up to the first dielectric layer 22
0 into the board holder 13.

After the ZnS pellets are attached to the electron beam evaporation source 11, vacuum evacuation is performed. The pressure is lXl0”T.

The ZnS pellets were degassed at a temperature below rr, and vapor deposition was started after the substrate temperature reached 200°C. BCPM, which is a luminescence center raw material, was introduced into the vacuum vessel 10 with the temperature of the raw material cylinder 15 at 5° C. and the flow rate of hydrogen carrier gas at 2 cc/min. The degree of vacuum during this vapor deposition is ~1Xl
The deposition rate of the ZnS:Mn film was approximately 30 nm/min, and the thickness of the light emitting layer 13 was 600 nm. The ZnS:Mn thin film EL device thus formed emitted yellow-orange light at 120V or higher when driven with a 60Hz sine wave voltage.6The luminance at 150V was 1.5 to 2 times that of the conventional one. Obtained.

(Second Example) In the second example, ZnS:F was deposited by RF sputtering method.
Target the luminescent center J using argon carrier gas.
A ZnS:Tb,F film was formed while introducing a JX material (C,H,)3Tb (abbreviated as CPTb).

FIG. 3 is a diagram showing a manufacturing apparatus in an embodiment of the method for manufacturing a semiconductor device according to the present invention. Inside the vacuum container 30, there are provided a target support device 31, an anode 32 with a built-in heater for heating the substrate, a gas raw material inlet 33, an inert gas supply port 34, and a gas evacuation port 35.

The luminescent center raw material is introduced from a temperature-controlled raw material cylinder 36 by a carrier gas whose flow rate is controlled. The inert gas is introduced under direct flow control.

Luminescence of ZnS:Tb,F film! Formation of No. 23 was carried out according to the following procedure. The glass substrate 2o formed up to the first dielectric layer 22 is used as an anode 32. After a target containing a mixture of ZnS and ZnF at a weight ratio of 9:1 is mounted on the target support device 31, vacuum evacuation is performed.

Press sputtering is performed in an argon atmosphere, and the substrate temperature is 2.
After reaching 00°C, sputtering was started. Tb
CPTb, which is a raw material, has a cylinder and piping temperature of 20
The argon carrier gas flow rate was 5 c c /
It was introduced by min. The degree of vacuum during sputtering was maintained at 0.02 Torr. ZnS at this time: Tb
The deposition rate of the F films was approximately 20 nm/min, and the thickness of the light emitting layer 13 was 600 nm. ZnS formed in this way
:Tb.

F thin film EL element is 180V driven by 60Hz sine wave voltage.
In this way, green light was emitted.

FIG. 4 shows the EL spectrum obtained with this device. This spectrum has a main peak at a line around 545 nm caused by 'D4-7F, which is the inner shell transition of the Tb31 ion at the emission center.

Next, FIG. 5 shows the temperature-applied voltage characteristics of the ZnS:Tb,F thin film EL device according to the present invention and a conventional example formed by the conventional electron beam evaporation method. The brightness threshold voltage is about 20 in the present invention.
The reason why V is low is considered to be due to the difference in element film thickness. The relative luminance of the present invention at a point of 30 V from the threshold voltage was about 1.5 times that of the conventional example.

(Third Example) In the third example, SrS is used as a deposition source using an electron beam evaporation method, and hydrogen sulfide (Has), which is a reactive gas, and a nitrogen carrier gas are used as raw materials for luminescence (CSH,), Ce-C
S rS : Ce while introducing I.

A C1 thin film was formed.

The light emitting layer 13 of SrS:Ce, CI film was formed by the following procedure. As shown in the first embodiment, the glass substrate 10 formed up to the first dielectric M12 is placed on the substrate holder 13.
．． After SrS pellets are attached to the electron beam evaporation source 11, vacuum evacuation is performed. SrS when the pressure is less than 1X10”Torr
After the pellets were degassed and the substrate temperature reached 500° C., vapor deposition was started. (C5Hi)2Ce which is a C0H material
In C1, the cylinder temperature was set at 150° C., and the hydrogen carrier gas flow rate was introduced at 2 cc/min. The degree of vacuum during this vapor deposition was ~1 x 108'Torr, and SrS:Ce,C
The deposition rate of one film was approximately 50 nm/min, and the thickness of the light emitting layer 13 was 1.5 μm. In order to confirm the change in the Celp degree relative to Sr in the light emitting layer of the SrS:Ce,C1 thin film EL device thus formed, Ce
The distribution of the center in the film thickness direction was investigated by Auger analysis.

Figure 6 shows the analysis results, with the horizontal axis representing the sputtering time and the vertical axis representing the Auger signal intensity.Fluctuations in the Ce concentration can be seen at the extreme surface of the thin film due to adhesion of oxygen, carbon, etc. after deposition, but within the film. In this case, Ce is applied more uniformly to Sr than before.
It was confirmed that the fluctuation was ±10%.

(Fourth Example) In the fourth example, two types of luminescence center raw materials ((C (CH,)3)
2-C3H()2) 3P r (P r (D PM
), (C,H,), and Mn (abbreviated as CPM) were introduced to form a SrS:Pr,Mn thin film.

The formation of the light emitting layer 13 of SrS:Pr,Mn film is the same as the procedure of the third embodiment.

The feature of this embodiment is that two types of luminescent center raw materials are used at the same time, and the modified part of the semiconductor manufacturing equipment for this purpose and the flow sequence of the raw material gas are shown in FIG. Luminescent center raw material 1 contains 3 cylinders of P r (D P M ) (150°C
), a CPM cylinder (60° C.) is installed in the luminescence center raw material 2, and hydrogen carrier gas is introduced.

FIG. 8 shows the structure of the thin film EL device manufactured in this example. The light emitting layer includes a first light emitting layer 83a of SrS:Pr and SrS:Pr.
rS: This is a stack of M n second light emitting layers 83b. First, the three-way valve v1 is set to ○N state and P r (DP
M) 3 was introduced into a vacuum container and a SrS:Pr film was formed for 10 minutes. At this time, the three-way valve v2 is in the OFF state, and the Mn raw material is processed in the exclusion device.The primary valve v2 is turned on, and the CP
M is introduced to form a SrS:Mn film for 10 minutes.

This operation was repeated to form a laminated light emitting layer (500 nm thick) of SrS:Pr/SrS:Mn. P in this luminescent layer
The distribution of r;: and Mn in the film thickness direction is as follows:
It was confirmed that r and Mn were distributed alternately.

[Effects of the Invention] As explained above, according to the semiconductor device manufacturing method and semiconductor manufacturing apparatus of the present invention, luminescent ions can be added more uniformly into the luminescent layer, so the formation of non-radiative centers such as clusters is suppressed. A thin film EL element with high brightness and high efficiency can be obtained. Furthermore, the addition area and concentration of luminescent ions can be easily controlled. The organic compound as the luminescent center raw material shown in the present invention can be easily applied to physical vapor deposition and chemical vapor deposition.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of the semiconductor device manufacturing apparatus used in the present invention, FIG. 2 is a schematic diagram showing an example of the structure of the thin film EL element manufactured in the first example, and FIG. A schematic diagram showing an example of the semiconductor device manufacturing apparatus used in Example 2, FIG. 4 is a graph showing the emission spectrum of the thin film EL element manufactured in Example 2, and FIG.
FIG. 6 is a graph showing the relationship between the applied voltage and the luminous density of the thin film EL device fabricated in Example 3. FIG. 6 is a graph showing the depth profile of luminescent ions in the luminescent layer fabricated in Example 3. The figure is a schematic diagram showing an example of the piping system for the luminescent center raw material used in the fourth example, and FIG. 8 is a schematic diagram showing an example of the structure of the thin film EL cord produced in the fourth example. Explanation of symbols 10... Vacuum vessel, 11... Electron beam evaporation source, 12.
...Substrate holder, 13...Nozzle, 14...Gas nozzle, Atsushi Atsushi 5

Claims (9)

[Claims] 1. In a semiconductor device containing a luminescent material, especially a thin film electroluminescent element, when producing a luminescent material thin film, so-called luminescent layer, a luminescent host material is formed by physical vapor deposition, and one or more organic compounds are supplied as luminescent ions. A method for manufacturing a semiconductor device, comprising independently supplying luminescent ions as a source. 2. As the organic compound, (C_5H_5)_3X
, (CH_3C_5H_4)_3X (where X is Ce
, Eu, Tb, Sm, Tm, Er, Pr, Dy or Ho), (C_5H_5)_2Mn, (CH_3
The method for manufacturing a semiconductor device according to claim 1, characterized in that at least one compound selected from the group consisting of C_5H_4)_2Mn is used. 3. As the organic compound (C_5H_5)_2X-M
(Here, X is Ce, Eu, Tb, Sm, Tm, Er,
Pr, Dy or Ho, and M is F, Cl, Br
2. The method of manufacturing a semiconductor device according to claim 1, wherein at least one compound selected from the group consisting of: (1) or (1) is used. 4. The organic compound is (R_1R_2C_3HO_2)_3X (where X is
Ce, Eu, Tb, Sm, Tm, Er, Pr, Dy or Ho, and R_1 and R_2 are CH_3, C(
The method for manufacturing a semiconductor device according to claim 1, characterized in that at least one compound selected from the group consisting of CH_3)_3 or CF_3 is used. 5. In the method for manufacturing a semiconductor device according to any one of claims 1 to 4, the light-emitting layer matrix material includes a group of Zn, Cd, Mg, Ca, Sr, Ba, S, and S.
A method for manufacturing a semiconductor device, characterized in that a compound containing one or more elements from the groups e and Te is used. 6. In the method for manufacturing a semiconductor device according to any one of claims 1 to 5, R_2,X (where X represents S, Se or Te, and R represents H, CH_
3 or C_2H_5) and simultaneously supplying at least one compound. 7. As an apparatus for carrying out the method for manufacturing a semiconductor device according to any one of claims 1 to 6, a supply port for the organic compound is provided in the vapor deposition container for the physical vapor deposition method.
or more, the compound R_2X (where X is S, Se or Te, or R is H, CH, or C_2H
A manufacturing apparatus for a semiconductor device, characterized in that it is provided with at least one supply port for (representing _5). 8. The light-emitting layer matrix material is Zn, Cd, Mg, Ca.
, Sr, Ba, and at least one element selected from the group S, Se, Te. A method for manufacturing a semiconductor device, characterized in that a compound is added by chemical vapor deposition. 9. 1. A semiconductor device using a thin film of a light-emitting material with fluctuations in the concentration of a depth profile of light-emitting ions in a light-emitting layer having a lower limit of 20% and an upper limit of 20%.