JP2006278230A - Organic light emitting display device, and protecting film forming method of organic light emitting display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an organic light emitting display device in which device characteristic is not damaged and which is superior in long-term reliability, in the organic light emitting display device using hydrogenated amorphous nitride silicon film as a protecting film. <P>SOLUTION: This is the organic light emitting display device in which the organic light emitting element 20 in which a first electrode 22, an organic material layer 23, and a second electrode 26 composed of a transparent electrode material are sequentially laminated on a substrate 21 is installed on the substrate 21 in the number of one or more, and in which the respective organic light emitting elements 20 are covered by the protecting film 27. The protecting film 27 is formed by hydrogenated amorphous silicon nitride, and a hydrogen content (cm<SP>-3</SP>) in the protecting film 27 is within the range of ±10% of a value of Ch (cm<SP>-3</SP>) expressed by a following formula (1), provided that the minimum value of glass transition temperature of the organic materials of the organic material layer 23 is Tg<SB>min</SB>(°C). The formula (1) is Ch=-8.6×10<SP>19</SP>Tg<SB>min</SB>+2.6×10<SP>22</SP>. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic light emitting display device provided with an organic light emitting element such as an organic electroluminescence element and a method for forming a protective film of the organic light emitting display device.

  In recent years, with the diversification of information equipment, flat display elements that consume less power and are thinner than CRTs (cathode ray tubes) have attracted attention. In such flat display elements, organic electroluminescence elements (organic EL elements) are particularly attracting attention because they have characteristics such as high efficiency, thinness, light weight, and low viewing angle dependency. The research and development of the display has been active.

  In the organic EL element, electrons and holes are injected into the light emitting part from the electron injection electrode (cathode) and the hole injection electrode (anode), respectively, and the injected electrons and holes are recombined at the emission center, whereby organic molecules are formed. When the organic molecule returns to an excited state and returns from the excited state to the ground state, it emits fluorescence. Such a light emission phenomenon is applied to a display.

  This organic EL element can change a luminescent color by selecting the fluorescent substance which is a luminescent material, and the expectation for the application to the display element to multicolor, full color, etc. is increasing.

  An organic electroluminescent device (organic EL device) includes a plurality of organic EL elements, and each organic EL element constitutes a pixel. In particular, an active matrix organic EL device provided with a TFT (thin film transistor) as a switching element for each pixel can hold display data for each pixel, so that a large screen and high definition can be achieved. It is considered as the leading role of the element.

  A normal organic EL device includes a hole injection electrode made of a transparent conductive film, a light emitting layer made of an organic material, and an electron injection electrode made of a metal on a glass substrate, and light emitted from the light emitting layer is made of a transparent electrode film. It passes through the injection electrode and is taken out from the back side of the glass substrate.

  On the other hand, a structure in which light emitted from the light emitting layer is extracted from the upper surface side by forming an electron injection electrode on the upper side of each organic EL element using a transparent conductive film or a semitransparent metal film (so-called top emission structure). Has been proposed.

  In the organic EL device having the top emission structure, the color filter or the color conversion layer can be disposed on the upper electron injection electrode, so that the manufacture becomes easy. Further, in an organic EL device having an active matrix top emission structure, light emitted from the light emitting layer can be extracted outside without being blocked by a plurality of TFTs on the glass substrate. Therefore, the aperture ratio of the pixel (the ratio of the area of the light emitting portion in the pixel) is improved.

  In an organic EL display device, sealing is performed using an inorganic material such as glass or a metal can in order to prevent oxygen and moisture from entering the element. However, in an organic EL device having a top emission structure, when a hollow can is placed on the screen side from which light emission is extracted, a phenomenon in which multiple images appear is generated. For this reason, it is necessary to seal and seal with a flat plate.

  On the other hand, it has been proposed to use a silicon nitride film formed by plasma CVD (chemical vapor deposition) or sputtering as a moisture-resistant protective film for organic EL elements. In particular, the plasma CVD method is expected to be put to practical use because it has advantages such as high-speed film formation and excellent coverage as compared with the sputtering method. However, when it is applied to an actual device, it has not reached a point where the inherent moisture resistance can be exhibited.

  It is known that when the number of N—H bonds in the silicon nitride film increases, the moisture resistance is hindered. Therefore, in general, it is considered preferable to increase the substrate temperature when depositing a hydrogenated amorphous silicon nitride film (a-SiN: H film) to reduce the amount of bonded hydrogen. Further, as described in Non-Patent Document 1, as a method for reducing the amount of hydrogen in the hydrogenated amorphous silicon nitride film, there is a method that uses ion bombardment in plasma.

However, the present inventors have found that simply increasing the substrate temperature or increasing the ion bombardment causes a problem that the device characteristics deteriorate.
Thin film production handbook, page 285, published by Kyoritsu Shuppan on March 25, 1991 The 65th JSAP Scientific Lecture Proceedings 1159 pages (September 2004)

  SUMMARY OF THE INVENTION An object of the present invention is to provide an organic light emitting display device which has excellent device characteristics and long-term reliability in an organic light emitting display device using a hydrogenated amorphous silicon nitride film as a protective film.

In the organic light emitting display device of the present invention, one or more organic light emitting elements in which a first electrode, an organic material layer, and a second electrode made of a transparent electrode material are sequentially stacked on a substrate are provided on the substrate. Each organic light emitting element is covered with a protective film, the protective film is formed of hydrogenated amorphous silicon nitride, and the hydrogen content (cm ⁻³ ) in the protective film is When the minimum temperature among the glass transition temperatures of each organic material in the organic material layer is Tg _min (° C.), within a range of ± 10% of the value of Ch (cm ⁻³ ) represented by the following formula: It is characterized by being.

Ch = −8.6 × 10 ¹⁹ Tg _min + 2.6 × 10 ²²
In the present invention, the protective film is formed from hydrogenated amorphous silicon nitride, and the amount of hydrogen contained in the protective film is within the above range, so that the device characteristics are not impaired and the organic light emitting display is excellent in long-term reliability. It is a device.

  In the organic light emitting device of the present invention, it is preferable that an organic metal complex is contained in the organic material layer. As the organometallic complex, the following aluminum quinolinol complex (Alq) is particularly preferably used.

  The organic material layer in the present invention includes at least a light emitting layer, and may further include carrier transport layers such as an electron transport layer and a hole transport layer. The aluminum quinolinol complex is preferably contained in such a light emitting layer or carrier transport layer.

In the method for forming a protective film of the present invention, at least one organic light-emitting device in which a first electrode, an organic material layer, and a second electrode made of a transparent electrode material are sequentially stacked on a substrate is provided on the substrate. A method of forming a protective film of an organic light emitting display device in which each organic light emitting element is covered with a protective film, using a hydrogenated gas of Si and a nitrogen-based gas as a source gas, and by plasma CVD, The amount of hydrogen contained in the protective film (cm ⁻³ ) is represented by the following formula when the minimum value of the glass transition temperature of each organic material in the organic material layer is Tg _min (° C.). ^-3 ), a hydrogenated amorphous silicon nitride film as a protective film is formed so as to be within a range of ± 10% of the value of ³ ).

Ch = −8.6 × 10 ¹⁹ Tg _min + 2.6 × 10 ²²
According to the present invention, by forming a hydrogenated amorphous silicon nitride film as a protective film so that the amount of hydrogen contained in the film is within the above range, damage to the organic material layer during the formation of the protective film is reduced. Thus, a protective film having excellent moisture resistance can be formed without impairing device characteristics. Therefore, an organic light emitting display device having excellent long-term reliability can be obtained.

The amount of hydrogen contained in the film can be controlled by adjusting the substrate temperature and the substrate bias voltage when depositing the protective film. For example, the substrate temperature during deposition of the protective film is set to a minimum value Tg _min or less of the glass transition temperature of each organic material in the organic material layer, and the substrate bias voltage is set to 50 V or less, so that The hydrogen content can be reduced. By increasing the substrate temperature during deposition of the protective film, the hydrogen content in the protective film can be reduced and the moisture resistance can be improved. On the other hand, if the substrate temperature becomes too high, the organic material having a low glass transition temperature is damaged in the organic material layer, so that the element driving voltage becomes high. In addition, by increasing the bias voltage (substrate bias voltage) applied to the substrate when forming the protective film, the hydrogen content in the film can be reduced. However, if the substrate bias voltage is too high, the organic material Since the organic material in the layer, particularly a metal complex such as an aluminum quinolinol complex, is damaged, the element driving voltage becomes high and good luminous efficiency cannot be obtained.

  According to the present invention, in an organic light emitting display device having a top emission structure using a hydrogenated amorphous silicon nitride film as a protective film, it is possible to provide an organic light emitting display device that is not impaired in device characteristics and excellent in long-term reliability. .

  Further, according to the method for forming a protective film of the present invention, it is possible to reduce the damage given to the organic material layer in the organic light emitting device, and to form a hydrogenated amorphous silicon nitride film with good film quality as the protective film.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic view showing a plasma CVD apparatus for forming a hydrogenated amorphous silicon nitride film (a-SiN: H film) in the present invention. As shown in FIG. 1, a lower electrode 6 is provided in the vacuum chamber 1, and a substrate 4 is placed on the lower electrode 6. A heater 5 is built in the lower electrode 6. A DC power supply 12 for applying a bias voltage to the substrate is connected to the lower electrode 6. An upper electrode 7 is provided above the lower electrode 6. A high frequency power source 11 is connected to the upper electrode 7 via a matching box 10. A gas cylinder 8 is connected to the upper electrode 7 via a mass flow controller 9. A source gas is supplied from the gas cylinder 8 to the upper electrode 7 through the mass flow controller 9, and a hole is formed in the upper electrode 7 so that the source gas flows in a shower shape toward the substrate 4.

  A high vacuum exhaust pump 3 is connected to the vacuum chamber 1 via a pressure adjusting valve 2, and the inside of the vacuum chamber 1 can be vacuum exhausted by the high vacuum exhaust pump 3.

  A hydrogenated amorphous silicon nitride film (a-SiN: H film) was formed on a single crystal silicon substrate using the plasma CVD apparatus shown in FIG. The thin film formation conditions are as follows.

Gas flow rate: SiH ₄ about 200 SCCM, NH ₃ about 100 SCCM, N ₂ about 2000 SCCM
Discharge frequency: 27.12 MHz
Input power density: 1 W / cm ²
Discharge pressure: 100 Pa
Deposition rate: 1 to 3 nm / sec Substrate temperature is 130 ° C., substrate bias voltage is 100 V, a-SiN: H film formed on a single crystal silicon substrate is subjected to SIMS (secondary ion mass spectrometry) measurement It was.

  FIG. 2 is a diagram showing the results of SIMS measurement.

As shown in FIG. 2, the hydrogen content in the film is about 1.3 × 10 ²² per cm ³ . Note that the measurement accuracy includes an error of about ± 10%.

  Next, the substrate temperature is set to 60 ° C., 95 ° C., 130 ° C., and 175 ° C., the substrate bias voltage is changed from 0 V to 200 V, an a-SiN: H film is formed, and the hydrogen content in each film is set as above. It measured by SIMS similarly.

  FIG. 3 is a diagram showing the measurement results. In addition, since discharge will not be stabilized when the substrate bias voltage exceeds 200V, the upper limit is 200V.

At each temperature, the lower limit of the hydrogen content is the hydrogen content when the substrate bias voltage is 200V, and the upper limit is the value when the substrate bias voltage is 0V. As shown in FIG. 3, the hydrogen content at 60 ° C. varies between 2.5 × 10 ²² atoms / cm ³ (substrate bias voltage 0 V) to 1.4 × 10 ²² / cm ³ (substrate bias voltage 200 V). is doing. At 95 ° C., it changes between 2.1 × 10 ²² pieces / cm ^{3 and} 1.2 × 10 ²² pieces / cm ³ . At 130 ° C., it changes between 1.7 × 10 ²² pieces / cm ^{3 to} 1.0 × 10 ²² pieces / cm ³ . At 175 ° C., which vary between 1.3 × 10 ²² atoms / cm ³ ~0.9 × 10 ²² atoms / cm ^3.

  From the above, it can be seen that the hydrogen content in the film can be controlled by changing the substrate temperature and the substrate bias voltage.

  Next, examples of the organic light emitting device (organic EL device) will be described.

Example 1
FIG. 4 is a schematic cross-sectional view showing the organic light emitting display element 20 in the present invention. As shown in FIG. 4, an anode 22 (thickness 100 nm) for injecting holes made of Ag is formed on a glass substrate 21 (thickness 700 μm), and the anode 22 is made of an organic material. An active layer 23 is formed. A cathode 26 (thickness 20 nm) for injecting electrons made of MgAg is formed on the active layer 23. A protective film 27 made of an a-SiN: H film is formed on the cathode 26 by plasma CVD. (Thickness 300 nm) is formed.

  The active layer 23 is configured by laminating a hole transport layer 24 and a light emitting layer 25 described below.

Hole transport layer 24: triphenyldiamine derivative NPB, glass transition temperature Tg = 95 ° C., thickness 70 nm
Light emitting layer 25: aluminum quinolinol complex Alq, glass transition temperature Tg = 175 ° C., thickness 70 nm
NPB has the following structure.

Each of the layers other than the protective film 27 can be formed using a vacuum evaporation method using a resistance heating boat with a degree of vacuum of 10 ⁻⁴ MPa or less.

<Examination of influence of substrate temperature>
In the organic light emitting display device having the structure shown in FIG. 4, when the a-SiN: H film as the protective film 27 is formed, the substrate temperature is set to 60 ° C., 80 ° C., 95 ° C. without applying the substrate bias voltage. The temperature was changed to 110 ° C. and 130 ° C., and an organic EL element as the organic light emitting display element 20 was produced.

The voltage at which the current density flowing in the organic EL element is 20 mA / cm ² (luminance: 100 to 300 cd / m ² ) is used as the driving voltage, and the relationship between the substrate temperature and the driving voltage is shown in FIG.

  As can be seen from FIG. 5, when the substrate temperature exceeds 95 ° C., the driving voltage increases. 95 ° C. is the glass transition temperature of NPB constituting the hole transport layer. Therefore, it is considered that the drive voltage increased due to the deterioration of the hole transport layer.

From the above, to form a minimum value Tg _min from protection at a high substrate temperature film of the glass transition temperature of the organic material in the organic material layer, an organic material having a glass transition temperature of Tg _min is the protective film forming It can be seen that the driving voltage of the obtained driving element is increased.

  Next, a moisture resistance test at a constant temperature and humidity (80 ° C., 95% RH) was performed on each of the device manufactured at a substrate temperature of 130 ° C. and the device manufactured at a substrate temperature of 60 ° C. The lighting condition was observed after 100 hours from the initial state (equivalent to 4000 hours endurance for half a year in indoor use). The results are shown in FIGS. FIG. 6 shows a lighting state of an element manufactured at a substrate temperature of 130 ° C., and FIG. 7 shows a lighting state of the element manufactured at a substrate temperature of 60 ° C.

  As apparent from the comparison between FIG. 6 and FIG. 7, the device manufactured at the substrate temperature of 130 ° C. shown in FIG. 6 was manufactured at the substrate temperature of 60 ° C. shown in FIG. In the element, it can be seen that the non-illuminated portion (so-called edge growth) is large above and below the pixel.

  FIG. 8 is a plan view showing an overlapping state of the layers of the light emitting element. As shown in FIG. 8, the metal cathode 26 extends in the horizontal direction of the drawing, and the metal cathode 26 also functions as a moisture-resistant layer. Therefore, when the element deteriorates due to moisture in the pixel, a non-lighting portion (edge growth) is formed. The pixel is formed from the vertical direction of the pixel. Therefore, as shown in FIG. 7, a non-lighting portion is formed from the vertical direction of the element.

  The results of the above moisture resistance test in each organic EL element in which a protective film was produced at substrate temperatures of 60 ° C., 95 ° C., and 130 ° C. are shown below. The ratio of the edge growth area after 100 hours of the moisture resistance test to the light emitting area in the initial state is shown below.

Substrate temperature 60 ° C: 23%
Substrate temperature 95 ° C: 5%
Substrate temperature 130 ° C: 1%
As described above, when a protective film is produced at a substrate temperature of 95 ° C., which is Tg _min , the increase in driving voltage can be reduced, but the edge growth area ratio is 5%, and the moisture resistance is not sufficient. Recognize.

<Examination of influence of substrate bias voltage>
When the substrate bias voltage in forming the protective film is increased and ion bombardment is applied to the organic EL element, there is a concern that the organic material layer may be damaged. As one method of the evaluation, damage evaluation by PL (fluorescence) emission observation described in Non-Patent Document 2 was performed.

  A sample as shown in FIG. 9 was prepared as a sample for damage evaluation. As shown in FIG. 9, an Alq layer 32 (thickness 70 nm) is formed on a glass substrate 31, an MgAg layer 33 (thickness 20 nm) is formed thereon, and an a-SiN: H film 34 ( A sample 30 having a thickness of 10 nm was formed. When the a-SiN: H film 34 was formed, the a-SiN: H film 34 was formed under the conditions of no substrate bias voltage application (0 V) and substrate bias voltage application 25 V, 50 V, 100 V, and 200 V.

  For each sample produced as described above, PL measurement before the formation of the a-SiN: H film and PL measurement after the formation of the a-SiN: H film were performed and are shown in FIGS.

  10 and 11, the thin line (upper line) shows the PL waveform before the formation of the a-SiN: H film, and the thick line (lower line) shows the PL waveform after the formation of the a-SiN: H film. ing.

  FIG. 10A shows the PL intensity of a sample with no substrate bias applied (0 V) and a substrate bias of 25 V applied, and FIG. 10B shows the PL intensity when the substrate bias voltage is 50 V. FIG. 11A shows the PL intensity when the substrate bias voltage is 100V, and FIG. 11B shows the PL intensity when the substrate bias voltage is 200V.

  As apparent from FIGS. 10 and 11, when the substrate bias voltage is 0 V to 25 V, almost no deterioration is observed in the PL intensity, and it is considered that the damage due to ion bombardment is small. It can be seen that when the substrate bias voltage is 50 V, slight damage due to ion bombardment is recognized, and when the substrate bias voltage exceeds 100 V, damage due to considerable ion bombardment occurs.

  Next, in the organic EL element shown in FIG. 4, the element driving voltage was measured when an a-SiN: H film having a thickness of 300 nm was formed as the protective film 27 at various substrate bias voltages.

  FIG. 12 is a diagram showing element drive voltages when a-SiN: H films are produced with various substrate bias voltages. As can be seen from FIG. 12, when the substrate bias voltage exceeds 50V, the drive voltage is remarkably increased.

  From the above, it can be seen that it is preferable to form the protective film with the substrate bias voltage set to 50 V or less.

  Next, the substrate temperature was set to 95 ° C., the substrate bias voltage was changed to 0 V, 25 V, and 50 V to produce an organic EL element, and the above moisture resistance test was performed. The area ratio of the edge growth after 100 hours of the moisture resistance test with respect to the light emitting area in the initial state is shown below.

Substrate bias voltage 0V: 5%
Substrate bias voltage 25V: 3%
Substrate bias voltage 50V: 1%
From the above results, it can be seen that when the substrate bias voltage is 50 V, good moisture resistance can be obtained.

From the above results, it can be seen that high moisture resistance can be obtained by setting the substrate bias voltage to 50 V and the substrate temperature to the minimum value Tg _min of the glass transition temperatures of the organic materials in the organic material layer. For example, when the substrate temperature was 95 ° C. and the substrate bias voltage was 50 V, the amount of hydrogen in the protective film was 1.7 × 10 ²² pieces / cm ³ and an organic material layer having a Tg _min of 95 ° C. was used. In the organic EL element, the best moisture resistance can be obtained. In order to further extend the indoor continuous use time, a thicker a-SiN: H film may be formed while maintaining this film quality.

(Example 2)
In Example 1, except that the hole transport layer 24 is formed using TPD (Tg = 60 ° C.) which is a triphenyldiamine derivative so as to have a thickness of 70 nm, an organic EL element similar to that in Example 1 is prepared. It examined like the above.

As a result, when the protective film was formed at a substrate temperature of 60 ° C. and a substrate bias voltage of 50 V, the amount of hydrogen in the film was 2.1 × 10 ²² atoms / cm ³ , and the best moisture resistance was obtained.

  The TPD has the following structure.

(Example 3)
In Example 1, an organic EL device was prepared in the same manner as in Example 1 except that the hole transport layer 24 was made of TPTE2 (Tg = 130 ° C.), which is a triphenylamine derivative, and had a thickness of 70 nm. I examined it.

As a result, when the protective film was formed by applying a substrate temperature of 130 ° C. and a substrate bias voltage of 50 V, the amount of hydrogen in the film was 1.4 × 10 ²² atoms / cm ³ , and the best moisture resistance characteristics were obtained. .

  Note that TPTE2 has the following structure.

Example 4
In Example 1, an organic EL device was produced in the same manner as in Example 1 except that the hole transport layer 24 was formed using polyethylenedioxythiophene PEDOT / PSS (Tg = 200 ° C. or higher) so as to have a thickness of 100 nm. And it examined like the above.

As a result, the amount of hydrogen in the protective film when the protective film is formed by applying the substrate temperature of 175 ° C. and the substrate bias voltage of 50 V is 1.1 × 10 ²² / cm ³ , and the best moisture resistance is obtained. It was. In this case, the minimum value Tg _min of the glass transition temperature in the organic material layer is 175 ° C. of Alq.

  PEDOT / PSS has the following structure.

FIG. 13 shows the relationship between Tg corresponding to Tg _min in the organic material layers of Examples 1 to 4 and the hydrogen content in the a-SiN: H film showing the best moisture resistance property in that case. Yes.

  When a correlation function was applied to the relationship shown in FIG. 13, a relational expression as shown in FIG. 14 was obtained.

Therefore, the best moisture resistance can be obtained by setting the hydrogen content in the protective film made of the a-SiN: H film within a range of ± 10% of the value of Ch (cm ⁻³ ) represented by the following formula. It turns out that it is obtained.

Ch = −8.6 × 10 ¹⁹ Tg _min + 2.6 × 10 ²²

The schematic diagram which shows the plasma CVD apparatus used in forming the protective film in embodiment according to this invention. The figure which shows the SIMS measurement result of a hydrogenated amorphous silicon nitride film. The figure which shows the relationship between the substrate temperature at the time of a-SiN: H film formation, and the hydrogen content in a film | membrane. The typical sectional view showing an example of the structure of the organic light emitting element according to the present invention. The figure which shows the relationship between the substrate temperature at the time of protective film formation of an organic light emitting element, and element drive voltage. The figure which shows the result of a moisture-proof test. The figure which shows the result of a moisture-proof test. The top view which shows the overlapping state of each layer in an organic light emitting element. The typical sectional view showing the structure of the sample for evaluating the damage by the ion impact at the time of forming the a-SiN: H film. The figure which shows PL intensity before the film formation of the sample which formed the a-SiN: H film | membrane by changing a substrate bias voltage, and after film formation. The figure which shows PL intensity before the film formation of the sample which formed the a-SiN: H film | membrane by changing a substrate bias voltage, and after film formation. The figure which shows the relationship between a substrate bias voltage and an element drive voltage. Diagram showing the relationship between the film hydrogen content in the protective film exhibiting the best moisture resistance and Tg _min the organic light-emitting device. The figure which described the relational expression showing a correlation in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vacuum chamber 2 ... Pressure adjustment valve 3 ... High vacuum exhaust pump 4 ... Substrate 5 ... Heater 6 ... Lower electrode 7 ... Upper electrode 8 ... Gas cylinder 9 ... Mass flow controller 10 ... Matching box 11 ... High frequency power supply 12 ... DC power supply DESCRIPTION OF SYMBOLS 20 ... Organic light emitting element 21 ... Glass substrate 22 ... Anode 23 ... Active layer (organic material layer)
DESCRIPTION OF SYMBOLS 24 ... Hole transport layer 25 ... Light emitting layer 26 ... Cathode 27 ... Protective film 30 ... Sample 31 ... Glass substrate 23 ... Alq layer 33 ... MgAg layer 34 ... a-SiN: H film

Claims (5)

One or more organic light emitting devices in which a first electrode, an organic material layer, and a second electrode made of a transparent electrode material are sequentially laminated on the substrate are provided on the substrate, and each organic light emitting device is An organic light emitting display device covered with a protective film,
The protective film is made of hydrogenated amorphous silicon nitride, and the hydrogen content (cm ⁻³ ) in the protective film is the lowest value among the glass transition temperatures of the organic materials in the organic material layer. An organic light-emitting display device characterized by being within a range of ± 10% of a value of Ch (cm ⁻³ ) represented by the following formula when Tg _min (° C.) is used.
Ch = −8.6 × 10 ¹⁹ Tg _min + 2.6 × 10 ²²   The organic light-emitting display device according to claim 1, wherein an organic metal complex is contained in the organic material layer.   The organic light-emitting display device according to claim 2, wherein the organometallic complex is an aluminum quinolinol complex. One or more organic light emitting devices in which a first electrode, an organic material layer, and a second electrode made of a transparent electrode material are sequentially laminated on the substrate are provided on the substrate, and each organic light emitting device is A method of forming the protective film of an organic light emitting display device covered with a protective film,
Using a hydrogenation gas of Si and a nitrogen-based gas as a raw material gas, the amount of hydrogen contained in the protective film (cm ⁻³ ) of the glass transition temperature of each organic material in the organic material layer is determined by plasma CVD. When the minimum value is Tg _min (° C.), the hydrogenated amorphous silicon nitride as the protective film is within a range of ± 10% of the value of Ch (cm ⁻³ ) represented by the following formula: A protective film forming method for an organic light emitting display device, comprising forming a film.
Ch = −8.6 × 10 ¹⁹ Tg _min + 2.6 × 10 ²² 5. The method for forming a protective film of an organic light emitting display device according to claim 4, wherein the amount of hydrogen contained in the film is controlled by controlling the substrate temperature and the substrate bias voltage during film deposition.