JPH05347187A - Thin film el element - Google Patents
Thin film el elementInfo
- Publication number
- JPH05347187A JPH05347187A JP4340163A JP34016392A JPH05347187A JP H05347187 A JPH05347187 A JP H05347187A JP 4340163 A JP4340163 A JP 4340163A JP 34016392 A JP34016392 A JP 34016392A JP H05347187 A JPH05347187 A JP H05347187A
- Authority
- JP
- Japan
- Prior art keywords
- film
- thin film
- light emitting
- layer
- emitting layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000010409 thin film Substances 0.000 title claims abstract description 57
- 229910003071 TaON Inorganic materials 0.000 claims abstract description 39
- 229910052814 silicon oxide Inorganic materials 0.000 claims abstract description 33
- 239000010408 film Substances 0.000 claims description 162
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 24
- 239000012528 membrane Substances 0.000 abstract 3
- 229910052581 Si3N4 Inorganic materials 0.000 abstract 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- 235000012239 silicon dioxide Nutrition 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 238000004544 sputter deposition Methods 0.000 description 11
- 239000000758 substrate Substances 0.000 description 10
- 230000015556 catabolic process Effects 0.000 description 8
- 239000011521 glass Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000032683 aging Effects 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229910018507 Al—Ni Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000005401 electroluminescence Methods 0.000 description 1
- 238000005566 electron beam evaporation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 229910003437 indium oxide Inorganic materials 0.000 description 1
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
Landscapes
- Electroluminescent Light Sources (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は薄膜ＥＬ(エレクトロ
・ルミネッセンス)素子に関し、より詳しくは、発光層
と電極層との間に絶縁層を有する薄膜ＥＬ素子に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film EL (electroluminescence) device, and more particularly to a thin film EL device having an insulating layer between a light emitting layer and an electrode layer.
【０００２】[0002]
【従来の技術】この種の薄膜ＥＬ素子としては、図８に
示すように、ＺnＳ:Ｍnなどからなる発光層１０４とＩ
ＴＯ(錫添加酸化インジウム)電極層１０２,金属電極層
１０６との間に、それぞれＴaＯＮ膜(窒素を含有させた
Ｔa2Ｏ5膜)からなる絶縁層１０３,１０５を設けたもの
が提案されている(特開平１−１３０４９６号公報)。上
記文献(公報)には、ＴaＯＮ膜は比誘電率εrが２０〜２
３と比較的大きいことから、通常のＳiＯ2膜,Ｙ2Ｏ3膜,
Ｓi3Ｎ4膜(比誘電率εrが１０以下)などよりも薄膜ＥＬ
素子の絶縁層として有益であり、発光特性を改善できる
旨が記載されている。なお、１０１はガラス基板であ
る。2. Description of the Related Art As a thin film EL device of this type, as shown in FIG. 8, a light emitting layer 104 made of ZnS: Mn or the like and an I
It has been proposed to provide insulating layers 103 and 105 made of TaON film (Ta 2 O 5 film containing nitrogen) between the TO (tin-doped indium oxide) electrode layer 102 and the metal electrode layer 106, respectively. (Japanese Patent Laid-Open No. 1-130496). In the above document (publication), the TaON film has a relative dielectric constant εr of 20 to 2
3 is relatively large, so a normal SiO 2 film, Y 2 O 3 film,
Thin film EL than Si 3 N 4 film (relative permittivity εr is 10 or less)
It is described that it is useful as an insulating layer of an element and can improve the light emission characteristics. In addition, 101 is a glass substrate.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、本発明
者の実験によって、ＴaＯＮ膜を絶縁層とする薄膜ＥＬ
素子は、実際には、図４中に特性(c)で例示するよう
に、発光層が劣化して、発光特性(電圧−輝度特性)が通
常のＳiＯ2膜,Ｙ2Ｏ3膜,Ｓi3Ｎ4膜からなるもの(同図中
に特性(b)で示す)よりも悪くなることが分かった。この
事情は、Ｔa2Ｏ3膜(比誘電率εrが２３〜３０)を絶縁層
とする薄膜ＥＬ素子でも同じであった。However, according to the experiments of the present inventor, a thin film EL having a TaON film as an insulating layer is used.
In the device, as illustrated by the characteristic (c) in FIG. 4, the light emitting layer is actually deteriorated so that the light emitting characteristics (voltage-luminance characteristics) are normal SiO 2 film, Y 2 O 3 film, and Si. It was found to be worse than the one made of 3 N 4 film (shown by the characteristic (b) in the figure). This circumstance was the same in the thin film EL element having the Ta 2 O 3 film (relative permittivity εr of 23 to 30) as the insulating layer.
【０００４】そこで、この発明の目的は、発光特性およ
び信頼性に優れた薄膜ＥＬ素子を提供することにある。Therefore, an object of the present invention is to provide a thin film EL element having excellent light emitting characteristics and reliability.
【０００５】[0005]
【課題を解決するための手段および作用】上記目的を達
成するため、第１の発明の薄膜ＥＬ素子は、発光層と、
この発光層を挟む一対の電極層を有し、上記電極層のう
ち少なくとも一方の電極層と上記発光層との間に絶縁層
を介在させた薄膜ＥＬ素子において、上記絶縁層は、上
記電極層側に配されたＴaＯＮ膜と、上記発光層側に配
されたＳi3Ｎ4膜またはＳiＯＮ膜とからなることを特徴
としている。ここで、ＳiＯＮ膜とは、Ｓi,ＯおよびＮ
からなる膜(組成比は任意)を示している。In order to achieve the above object, the thin film EL device of the first invention comprises a light emitting layer,
In a thin film EL element having a pair of electrode layers sandwiching the light emitting layer, wherein an insulating layer is interposed between at least one of the electrode layers and the light emitting layer, the insulating layer is the electrode layer. It is characterized by comprising a TaON film disposed on the side and a Si 3 N 4 film or a SiON film disposed on the side of the light emitting layer. Here, the SiON film means Si, O and N.
The film is composed of (composition ratio is arbitrary).
【０００６】本発明者は、絶縁層としてＴaＯＮ膜とＳi
3Ｎ4膜またはＳiＯＮ膜とを組み合わせることにより、
信頼性および発光特性に優れた薄膜ＥＬ素子を実現し
た。すなわち、比誘電率εrが大きいＴaＯＮ膜によって
発光しきい値電圧を下げるとともに、発光層側に安定な
Ｓi3Ｎ4膜またはＳiＯＮ膜を配することによって上記Ｔ
aＯＮ膜と発光層との反応を抑えて輝度の低下を防ぎ、
かつ、絶縁破壊耐圧を高めた。これにより、従来に比し
て発光特性および信頼性を向上させることができた。The present inventor has used a TaON film and Si as an insulating layer.
By combining with 3 N 4 film or SiON film,
We have realized a thin film EL device with excellent reliability and light emission characteristics. That is, the emission threshold voltage is lowered by the TaON film having a large relative permittivity εr, and the stable Si 3 N 4 film or the SiON film is arranged on the light emitting layer side to obtain the above T
The reaction between the aON film and the light emitting layer is suppressed to prevent a decrease in brightness,
Moreover, the dielectric breakdown voltage is increased. As a result, it was possible to improve the light emission characteristics and reliability as compared with the conventional case.
【０００７】このように改善できたのは、次の理由によ
る。すなわち、図５中に特性(d)で示すように、絶縁層
を構成する膜の比誘電率εrの平均値が６．２程度(通常
のＳiＯ2膜,Ｙ2Ｏ3膜,Ｓi3Ｎ4膜に相当するレベル)であ
る場合は、絶縁層の総膜厚は４０００Å程度に設定され
る。総膜厚が４０００Å以上だと発光しきい値電圧Ｖth
が大きくなり過ぎ(１８０Ｖ以上となる)、逆に、４００
０Å以下だと絶縁層の破壊耐圧が低下して信頼性を損な
うからである。これに対して、絶縁層としてＴaＯＮ膜
とＳi3Ｎ4膜またはＳiＯＮ膜とを組み合わせたものは、
比誘電率εrの平均値が２０程度となる。したがって、
同図中に特性(e)で示すように、ＴaＯＮ膜の膜厚が〜６
０００Å、Ｓi3Ｎ4膜またはＳiＯＮ膜の膜厚が〜１００
０Å(したがって、総膜厚が〜７０００Å)であっても発
光しきい値電圧Ｖthを１５０Ｖ程度に抑えることができ
る。The reason why the above improvement can be made is as follows. That is, as shown by the characteristic (d) in FIG. 5, the average value of the relative permittivity εr of the film forming the insulating layer is about 6.2 (normal SiO 2 film, Y 2 O 3 film, Si 3 N film). If the level is equivalent to 4 films), the total thickness of the insulating layer is set to about 4000 Å. When the total film thickness is 4000 Å or more, the light emission threshold voltage Vth
Is too large (over 180V), on the contrary, 400
This is because if it is 0 Å or less, the breakdown voltage of the insulating layer is lowered and the reliability is impaired. On the other hand, the combination of the TaON film and the Si 3 N 4 film or the SiON film as the insulating layer is
The average value of the relative permittivity εr is about 20. Therefore,
As shown by the characteristic (e) in the figure, the TaON film has a thickness of ~ 6.
000Å, Si 3 N 4 film or SiON film is ~ 100
Even if 0Å (thus, the total film thickness is up to 7,000Å), the light emission threshold voltage Vth can be suppressed to about 150V.
【０００８】ただし、ＴaＯＮ膜の膜厚が６０００Åを
超えるか、または、Ｓi3Ｎ4膜またはＳiＯＮ膜の膜厚が
１０００Åを超えると、発光しきい値電圧Ｖthが大きく
なり過ぎる。一方、ＴaＯＮ膜の膜厚が１０００Åを下
回ると、絶縁破壊耐圧を維持することができない(たと
え、Ｓi3Ｎ4膜またはＳiＯＮ膜の厚膜化でカバーしよう
としても、発光しきい値電圧Ｖthと両立できない)。ま
た、Ｓi3Ｎ4膜またはＳiＯＮ膜の膜厚が１００Åを下回
ると、ＴaＯＮ膜と発光層との反応を抑えることができ
ず、輝度の低下が生じる。結局、上記ＴaＯＮ膜の厚さ
を１０００〜６０００Å、上記Ｓi3Ｎ4膜またはＳiＯＮ
膜の厚さを１００〜１０００Åに設定するのが望まし
い。これにより、絶縁破壊耐圧を維持して信頼性を高め
た上、発光しきい値電圧を下げて発光特性を向上させる
ことができる。However, when the film thickness of the TaON film exceeds 6000Å or the film thickness of the Si 3 N 4 film or the SiON film exceeds 1000Å, the light emission threshold voltage Vth becomes too large. On the other hand, when the film thickness of the TaON film is less than 1000Å, the dielectric breakdown voltage cannot be maintained (even if the Si 3 N 4 film or the SiON film is made thicker, the emission threshold voltage Vth and Can't be compatible). Further, if the film thickness of the Si 3 N 4 film or the SiON film is less than 100 Å, the reaction between the TaON film and the light emitting layer cannot be suppressed and the brightness is lowered. After all, the thickness of the TaON film is 1000 to 6000Å, the Si 3 N 4 film or the SiON film is formed.
It is desirable to set the thickness of the film to 100 to 1000Å. As a result, it is possible to maintain the dielectric breakdown voltage, improve reliability, and reduce the light emission threshold voltage to improve light emission characteristics.
【０００９】また、上記目的を達成するため、第２の発
明の薄膜ＥＬ素子は、発光層と、この発光層を挟む一対
の電極層を有し、上記電極層のうち少なくとも一方の電
極層と上記発光層との間に絶縁層を介在させた薄膜ＥＬ
素子において、上記絶縁層は、ＴaＯＮ膜と、ＳiＯ2膜
またはＳiＯＮ膜とからなる単位層を複数重ねてなる積
層膜を有することを特徴としている。To achieve the above object, the thin film EL device of the second invention has a light emitting layer and a pair of electrode layers sandwiching the light emitting layer, and at least one of the electrode layers is provided. Thin film EL having an insulating layer interposed between the light emitting layer and the light emitting layer
The device is characterized in that the insulating layer has a laminated film formed by stacking a plurality of unit layers each including a TaON film and a SiO 2 film or a SiON film.
【００１０】この第２の発明の薄膜ＥＬ素子も、第１の
発明の薄膜ＥＬ素子と同様に、従来に比して信頼性およ
び発光特性を高めることができる。すなわち、比誘電率
εrが大きいＴaＯＮ膜によって発光しきい値電圧を下げ
ることができる。Like the thin film EL element of the first aspect of the invention, the thin film EL element of the second aspect of the invention can also have improved reliability and light emission characteristics as compared with conventional ones. That is, the emission threshold voltage can be lowered by the TaON film having a large relative permittivity εr.
【００１１】同時に、発光層側に安定なＳiＯ2膜または
ＳiＯＮ膜を配することによって、上記ＴaＯＮ膜と発光
層との反応を抑えて輝度の低下を防ぎ、かつ、絶縁破壊
耐圧を高めることができる。At the same time, by disposing a stable SiO 2 film or SiON film on the light emitting layer side, it is possible to suppress the reaction between the TaON film and the light emitting layer to prevent the decrease in brightness and to increase the dielectric breakdown voltage. it can.
【００１２】また、上記単位層を構成するＳiＯ2膜また
はＳiＯＮ膜と、ＴaＯＮ膜との膜厚比ＳiＯ2／ＴaＯＮ
またはＳiＯＮ／ＴaＯＮの値が、１／１５〜１０／１５
の範囲内にあるのが望ましい。この理由は、上記膜厚比
が１／１５を下回った場合、ＴaＯＮ膜と発光層との反
応が抑えられず、輝度が低下するからである。一方、上
記膜厚比が１０／１５を超えた場合、絶縁層の比誘電率
εrの平均値が小さくなって、発光しきい値電圧Ｖthを
下げることができないからである。The film thickness ratio of the SiO 2 film or the SiON film forming the unit layer to the TaON film is SiO 2 / TaON.
Or the value of SiON / TaON is 1/15 to 10/15
It is desirable to be within the range. The reason for this is that when the film thickness ratio is less than 1/15, the reaction between the TaON film and the light emitting layer cannot be suppressed, and the brightness decreases. On the other hand, if the film thickness ratio exceeds 10/15, the average value of the relative permittivity εr of the insulating layer becomes small and the light emission threshold voltage Vth cannot be lowered.
【００１３】また、本発明者は、上記単位層の厚さを減
少させて３００Å以下にした場合、図３に例示するよう
に、絶縁層全体の比誘電率εrの平均値が理論値よりも
大きくなることを発見した(なお、図３は、膜厚比ＳiＯ
Ｎ／ＴaＯＮの値が１／５の場合を示している。)。した
がって、上記単位層の厚さを３００Å以下に設定するこ
とによって、さらに発光しきい値電圧Ｖthを下げること
が可能となる。Further, when the thickness of the unit layer is reduced to 300 Å or less, the inventor has found that the average value of the relative permittivity εr of the entire insulating layer is higher than the theoretical value, as illustrated in FIG. It was discovered that the film thickness increases (Fig. 3 shows the film thickness ratio SiO
The case where the value of N / TaON is 1/5 is shown. ). Therefore, the light emission threshold voltage Vth can be further reduced by setting the thickness of the unit layer to 300 Å or less.
【００１４】また、第１の発明と同様の理由により、Ｔ
aＯＮ膜とＳiＯ2膜またはＳiＯＮ膜とからなる単位層を
複数重ねてなる積層膜の厚さを１０００〜６０００Åに
設定するのが望ましい。For the same reason as in the first aspect of the invention, T
It is desirable to set the thickness of the laminated film formed by stacking a plurality of unit layers each including the aON film and the SiO 2 film or the SiON film to 1000 to 6000Å.
【００１５】[0015]
【実施例】以下、この発明の薄膜ＥＬ素子を実施例によ
り詳細に説明する。EXAMPLES The thin film EL device of the present invention will be described in detail below with reference to examples.
【００１６】図１は、第１の発明の一実施例の薄膜ＥＬ
素子の断面を示している。この薄膜ＥＬ素子は、ガラス
基板１上に、発光層５と、この発光層５の両側に設けら
れた一対の電極層２,８と、電極層２,８と発光層５との
間に挟まれた絶縁層９,１０を有している。上記絶縁層
９は、電極層２側に配されたＴaＯＮ膜３と、発光層５
側に配されたＳi3Ｎ4膜(またはＳiＯＮ膜)４とからなっ
ている。一方、絶縁層１０は、発光層５側に配されたＳ
i3Ｎ4膜(またはＳiＯＮ膜)６と、電極層８側に配された
ＳiＯ2膜(またはＡl2Ｏ3膜)７とからなっている。FIG. 1 shows a thin film EL of one embodiment of the first invention.
The cross section of the element is shown. This thin film EL element is sandwiched between a light emitting layer 5, a pair of electrode layers 2 and 8 provided on both sides of the light emitting layer 5, and the electrode layers 2 and 8 and the light emitting layer 5 on a glass substrate 1. Insulating layers 9 and 10 are provided. The insulating layer 9 includes the TaON film 3 arranged on the electrode layer 2 side and the light emitting layer 5
It is composed of a Si 3 N 4 film (or a SiON film) 4 arranged on the side. On the other hand, the insulating layer 10 is an S layer disposed on the light emitting layer 5 side.
The i 3 N 4 film (or SiON film) 6 and the SiO 2 film (or Al 2 O 3 film) 7 arranged on the electrode layer 8 side are formed.
【００１７】この薄膜ＥＬ素子は次のようにして作製す
る。This thin film EL element is manufactured as follows.
【００１８】まず、ガラス基板１上に、ＩＴＯからなる
透明電極群(電極層)２を形成する。その上に、高周波ス
パッタ法により、Ｔa2Ｏ5焼結ターゲットと、Ａr,Ｏ2,
Ｎ2,N2Ｏを混合してなるスパッタガスとを用いて、厚さ
３０００ÅのＴaＯＮ膜３を堆積し、続いて、Ｓiターゲ
ットと、Ａr,Ｏ2,Ｎ2,Ｎ2Ｏを混合してなるスパッタガ
スとを用いて、厚さ２００ÅのＳi3Ｎ4膜４を堆積す
る。次に、電子線蒸着法,ＣＶＤ(化学気相成長)法また
はスパッタリング法により、厚さ８０００Å程度のＺn
Ｓ:Ｍnなどからなる発光層５を形成する。さらに、ＣＶ
Ｄ法またはスパッタリング法により、Ｓi3Ｎ4膜６,Ｓi
Ｏ2膜７(絶縁層１０)を形成する。絶縁層１０の厚さは
１５００Å程度とする。次に、真空中または不活性ガス
雰囲気中で、熱処理(６００℃,１時間)を行う。最後
に、Ａl−Ｎiなどからなる背面電極群(電極層)８を形成
する(作製完了)。First, a transparent electrode group (electrode layer) 2 made of ITO is formed on a glass substrate 1. On top of that, a Ta 2 O 5 sintering target, Ar, O 2 ,
A TaON film 3 having a thickness of 3000 Å is deposited using a sputtering gas formed by mixing N 2 and N 2 O, and then a Si target is mixed with Ar, O 2 , N 2 and N 2 O. Then, a Si 3 N 4 film 4 having a thickness of 200 Å is deposited by using the sputtering gas. Next, Zn having a thickness of about 8000 Å is formed by electron beam evaporation, CVD (chemical vapor deposition) or sputtering.
A light emitting layer 5 made of S: Mn or the like is formed. Furthermore, CV
The Si 3 N 4 film 6, Si is formed by the D method or the sputtering method.
The O 2 film 7 (insulating layer 10) is formed. The thickness of the insulating layer 10 is about 1500 Å. Next, heat treatment (600 ° C., 1 hour) is performed in vacuum or in an inert gas atmosphere. Finally, a back electrode group (electrode layer) 8 made of Al-Ni or the like is formed (manufacturing is completed).
【００１９】このようにして作製した薄膜ＥＬ素子は、
図４中に特性(a)で示すように、従来のもの(b),(c)に比
して、実際に発光特性を改善することができた。また、
絶縁破壊耐圧を高めることができた。さらに、通電時の
絶縁破壊による破壊孔も小さくなり、その発生数も減少
した。したがって、信頼性を改善することができた。The thin film EL device manufactured in this way is
As shown by the characteristic (a) in FIG. 4, it was possible to actually improve the light emitting characteristic as compared with the conventional ones (b) and (c). Also,
The breakdown voltage could be increased. Furthermore, the breakdown holes due to dielectric breakdown during energization became smaller, and the number of occurrences also decreased. Therefore, the reliability could be improved.
【００２０】図２は、第２の発明の一実施例の薄膜ＥＬ
素子の断面を示している。この薄膜ＥＬ素子は、図１に
示した薄膜ＥＬ素子と同様に、ガラス基板１上に、発光
層５と、この発光層５の両側に設けられた一対の電極層
２,８と、電極層２,８と発光層５との間に挟まれた絶縁
層１９,１０を有している(なお、同一構成部分は同一符
号で表している。)。上記絶縁層１９は、ＴaＯＮ膜１３
とＳiＯ2膜(またはＳiＯＮ膜)１４とからなる単位層を
複数重ねて構成されている。一方、絶縁層１０は、発光
層５側に配されたＳi3Ｎ4膜(またはＳiＯＮ膜)６と、電
極層８側に配されたＳiＯ2膜(またはＡl2Ｏ3膜)７とか
らなっている。FIG. 2 shows a thin film EL of one embodiment of the second invention.
The cross section of the element is shown. This thin-film EL element is similar to the thin-film EL element shown in FIG. 1 in that a light-emitting layer 5, a pair of electrode layers 2 and 8 provided on both sides of the light-emitting layer 5, and an electrode layer are provided on a glass substrate 1. It has insulating layers 19 and 10 sandwiched between 2 and 8 and the light emitting layer 5 (note that the same components are denoted by the same reference numerals). The insulating layer 19 is the TaON film 13
SiO 2 film (or SiON film) stacked plurality of unit layers composed of 14. is constituted as. On the other hand, the insulating layer 10 is composed of the Si 3 N 4 film (or SiON film) 6 arranged on the light emitting layer 5 side and the SiO 2 film (or Al 2 O 3 film) 7 arranged on the electrode layer 8 side. Is becoming
【００２１】この薄膜ＥＬ素子を作製する場合、まず、
ガラス基板１上に、ＩＴＯからなる透明電極群(電極層)
２を形成する。その上に、高周波スパッタ法により、Ｔ
a2Ｏ5焼結ターゲットと、Ａr,Ｏ2,Ｎ2,Ｎ2Ｏを混合して
なるスパッタガスとを用いてＴaＯＮ膜１３を堆積し、
続いて、基板１を移動(回転)させて、Ｓiターゲット
と、Ａr,Ｏ2,Ｎ2,Ｎ2Ｏを混合してなるスパッタガスと
を用いてＳiＯ2膜１４を堆積する。これにより、単位層
を構成する。このとき、単位層の厚さは例えば１００Å
とし、膜厚比ＳiＯ2／ＴaＯＮ＝１／５に設定する。そ
して、この手順を３０回繰り返して、厚さ３０００Åの
絶縁層１９を形成する。この後、図１に示した薄膜ＥＬ
素子の場合と同一の材料および条件によって、発光層５
と、絶縁層１０と、背面電極群(電極層)８を形成する
(作製完了)。When manufacturing this thin film EL element, first,
Transparent electrode group (electrode layer) made of ITO on the glass substrate 1
Form 2. In addition, by high frequency sputtering method, T
The TaON film 13 is deposited using an a 2 O 5 sintering target and a sputtering gas formed by mixing Ar, O 2 , N 2 , and N 2 O.
Then, the substrate 1 is moved (rotated), and the SiO 2 film 14 is deposited using the Si target and the sputtering gas formed by mixing Ar, O 2 , N 2 , and N 2 O. This constitutes a unit layer. At this time, the thickness of the unit layer is, for example, 100Å
And a film thickness ratio of SiO 2 / TaON = 1/5. Then, this procedure is repeated 30 times to form the insulating layer 19 having a thickness of 3000 Å. After this, the thin film EL shown in FIG.
According to the same material and conditions as in the case of the device, the light emitting layer 5
And an insulating layer 10 and a back electrode group (electrode layer) 8 are formed.
(Production completed).
【００２２】この薄膜ＥＬ素子も、従来のものに比し
て、発光特性および信頼性を改善することができた。し
かし、次の素子の検討結果で述べるように、信頼性は改
良の余地があった。This thin film EL element was also able to improve the light emitting characteristics and reliability as compared with the conventional one. However, there is room for improvement in reliability, as will be described in the next examination result of the device.
【００２３】図６は、第２の発明の別の実施例の薄膜Ｅ
Ｌ素子を示している。この薄膜ＥＬ素子は、ガラス基板
１上に、発光層５と、この発光層５の両側に設けられた
一対の電極層２,８と、電極層２,８と発光層５との間に
挟まれた絶縁層２０,１０を有している。上記絶縁層２
０は、電極層２側に配され、ＴaＯＮ膜１３とＳiＯ2膜
(またはＳiＯＮ膜)１４とからなる単位層を複数重ねて
なる積層膜１９と、発光層５側に配されたＳi3Ｎ4膜(ま
たはＳiＯＮ膜)１５とからなっている。一方、絶縁層１
０は、発光層５側に配されたＳi3Ｎ4膜(またはＳiＯＮ
膜)６と、電極層８側に配されたＳiＯ2膜(またはＡl2Ｏ
3膜)７とからなっている。FIG. 6 shows a thin film E of another embodiment of the second invention.
The L element is shown. This thin film EL element is sandwiched between a light emitting layer 5, a pair of electrode layers 2 and 8 provided on both sides of the light emitting layer 5, and the electrode layers 2 and 8 and the light emitting layer 5 on a glass substrate 1. Insulating layers 20, 10 are provided. The insulating layer 2
0 is arranged on the side of the electrode layer 2 and has a TaON film 13 and a SiO 2 film.
(Or SiON film) 14 is formed by stacking a plurality of unit layers, and a Si 3 N 4 film (or SiON film) 15 disposed on the light emitting layer 5 side. On the other hand, the insulating layer 1
0 is the Si 3 N 4 film (or SiON) arranged on the light emitting layer 5 side.
Film 6 and a SiO 2 film (or Al 2 O) arranged on the electrode layer 8 side.
3 films) and 7.
【００２４】この薄膜ＥＬ素子を作製する場合、まず、
ガラス基板１上に、ＩＴＯからなる透明電極群(電極層)
２を形成する。その上に、高周波スパッタ法により、Ｔ
a2Ｏ5焼結ターゲットと、Ａr,Ｏ2,Ｎ2,Ｎ2Ｏを混合して
なるスパッタガスとを用いてＴaＯＮ膜１３を堆積し、
続いて、基板１を移動(回転)させて、Ｓiターゲット
と、Ａr,Ｏ2,Ｎ2,Ｎ2Ｏを混合してなるスパッタガスと
を用いてＳiＯ2膜１４を堆積する。これにより、単位層
を構成する。このとき、単位層の厚さは例えば１００Å
とし、膜厚比ＳiＯ2／ＴaＯＮ＝１／５に設定する。そ
して、この手順を３０回繰り返して、厚さ３０００Åの
絶縁層１９を形成する。続いて、ＳiターゲットとＡr,
Ｏ2,Ｎ2,Ｎ2Ｏを混合してなるスパッタガスとを用いて
厚さ２００ÅのＳi3Ｎ4膜１５を堆積する。この後、図
１に示した薄膜ＥＬ素子の場合と同一の材料および条件
によって、発光層５と、絶縁層１０と、背面電極群(電
極層)８を形成する(作製完了)。When manufacturing this thin film EL element, first,
Transparent electrode group (electrode layer) made of ITO on the glass substrate 1
Form 2. In addition, by high frequency sputtering method, T
The TaON film 13 is deposited using an a 2 O 5 sintering target and a sputtering gas formed by mixing Ar, O 2 , N 2 , and N 2 O.
Then, the substrate 1 is moved (rotated), and the SiO 2 film 14 is deposited using the Si target and the sputtering gas formed by mixing Ar, O 2 , N 2 , and N 2 O. This constitutes a unit layer. At this time, the thickness of the unit layer is, for example, 100Å
And a film thickness ratio of SiO 2 / TaON = 1/5. Then, this procedure is repeated 30 times to form the insulating layer 19 having a thickness of 3000 Å. Next, the Si target and Ar,
A Si 3 N 4 film 15 having a thickness of 200 Å is deposited by using a sputtering gas formed by mixing O 2 , N 2 and N 2 O. Thereafter, the light emitting layer 5, the insulating layer 10, and the back electrode group (electrode layer) 8 are formed by using the same materials and conditions as in the case of the thin film EL element shown in FIG. 1 (manufacturing completed).
【００２５】本発明者は、上記Ｓi3Ｎ4膜１５の膜厚を
５０Å,１００Å,２００Åと変化させて試料を作製し
た。そして、加速エージングを行って、しきい値電圧の
変化ΔＶth,輝度の変化を調べたところ、図７に示すよ
うな結果が得られた。図７中、(f),(g),(h)はそれぞれ
Ｓi3Ｎ4膜１５の膜厚が５０Å,１００Å,２００Åのと
きのΔＶthを示し、(i),(j),(k)はそれぞれの輝度変化
率(変化ない状態を１とする)を示している。図から分か
るように、Ｓi3Ｎ4膜１５の膜厚が５０Åのときは、発
光層５に対するＴaＯＮ膜１３の影響を抑えることがで
きず、このため、しきい値電圧の変化ΔＶth,輝度の変
化率とも大きい。しかし、Ｓi3Ｎ4膜１５の膜厚が１０
０Å以上のときは、ＴaＯＮ膜１３の影響を抑えて、し
きい値電圧の変化ΔＶth,輝度変化率を大幅に改善する
ことができた。したがって、信頼性を大幅に改善するこ
とができた。また、Ｓi3Ｎ4膜１５の膜厚が１０００Å
を超えると発光しきい値電圧Ｖthが大きくなり過ぎる。
このため、Ｓi3Ｎ4膜１５の膜厚を１００〜１０００Å
に設定するのが望ましい。The present inventor manufactured samples by changing the film thickness of the Si 3 N 4 film 15 to 50Å, 100Å, 200Å. Then, acceleration aging was performed to examine the change in threshold voltage ΔVth and the change in luminance, and the results shown in FIG. 7 were obtained. In FIG. 7, (f), (g), and (h) represent ΔVth when the film thickness of the Si 3 N 4 film 15 is 50Å, 100Å, and 200Å, respectively, and (i), (j), (k) Indicates the rate of change in each luminance (the unchanged state is 1). As can be seen from the figure, when the film thickness of the Si 3 N 4 film 15 is 50 Å, the influence of the TaON film 13 on the light emitting layer 5 cannot be suppressed, and therefore, the change of the threshold voltage ΔVth and the luminance The rate of change is large. However, if the Si 3 N 4 film 15 has a thickness of 10
At 0 Å or more, the influence of the TaON film 13 was suppressed, and the change ΔVth in threshold voltage and the rate of change in luminance could be significantly improved. Therefore, the reliability could be improved significantly. Further, the film thickness of the Si 3 N 4 film 15 is 1000Å
If it exceeds, the light emission threshold voltage Vth becomes too large.
Therefore, the film thickness of the Si 3 N 4 film 15 is 100 to 1000 Å
It is desirable to set to.
【００２６】[0026]
【発明の効果】以上より明らかなように、第１の発明の
薄膜ＥＬ素子は、少なくとも一方の電極層と発光層との
間に介在させた絶縁層を、上記電極層側に配されたＴa
ＯＮ膜と、上記発光層側に配されたＳi3Ｎ4膜またはＳi
ＯＮ膜とで構成しているので、発光特性および信頼性を
向上させることができる。As is apparent from the above, in the thin film EL element of the first invention, the insulating layer interposed between at least one of the electrode layers and the light emitting layer is a Ta layer arranged on the electrode layer side.
ON film and Si 3 N 4 film or Si arranged on the light emitting layer side
Since it is composed of an ON film, it is possible to improve the light emission characteristics and reliability.
【００２７】また、第２の発明の薄膜ＥＬ素子は、少な
くとも一方の電極層と上記発光層との間に介在させた絶
縁層は、ＴaＯＮ膜と、ＳiＯ2膜またはＳiＯＮ膜とから
なる単位層を複数重ねてなる積層膜を有しているので、
この積層膜を上記電極層側に配し、Ｔaに対してバリア
として働くＳi3Ｎ4膜またはＳiＯＮ膜を発光層側に配す
ることによって、発光特性および信頼性を向上させるこ
とができる。In the thin film EL element of the second invention, the insulating layer interposed between at least one of the electrode layers and the light emitting layer is a unit layer composed of a TaON film and a SiO 2 film or a SiON film. Since it has a laminated film formed by stacking a plurality of
By arranging this laminated film on the electrode layer side and arranging the Si 3 N 4 film or the SiON film acting as a barrier against Ta on the light emitting layer side, the light emitting characteristics and reliability can be improved.
【図１】 第１の発明の一実施例の薄膜ＥＬ素子の断面
を示す図である。FIG. 1 is a diagram showing a cross section of a thin film EL element according to an embodiment of the first invention.
【図２】 第２の発明の一実施例の薄膜ＥＬ素子の断面
を示す図である。FIG. 2 is a diagram showing a cross section of a thin film EL element according to an example of the second invention.
【図３】 ＳiＯＮ膜とＴaＯＮ膜とからなる単位層の厚
さと比誘電率εrとの関係を示す図である。FIG. 3 is a diagram showing the relationship between the thickness of a unit layer composed of a SiON film and a TaON film and the relative permittivity εr.
【図４】 薄膜ＥＬ素子の発光特性を示す図である。FIG. 4 is a diagram showing a light emission characteristic of a thin film EL element.
【図５】 薄膜ＥＬ素子を構成する絶縁層の総膜厚と発
光しきい値電圧Ｖthとの関係を示す図である。FIG. 5 is a diagram showing a relationship between a total film thickness of an insulating layer forming a thin film EL element and a light emission threshold voltage Vth.
【図６】 第２の発明の別の実施例の薄膜ＥＬ素子の断
面を示す図である。FIG. 6 is a view showing a cross section of a thin film EL element of another embodiment of the second invention.
【図７】 薄膜ＥＬ素子のエージング結果を示す図であ
る。FIG. 7 is a diagram showing an aging result of a thin film EL element.
【図８】 従来の薄膜ＥＬ素子の断面を示す図である。FIG. 8 is a view showing a cross section of a conventional thin film EL element.
１ ガラス基板 ２ 透明電極
群 ３,１３ ＴaＯＮ膜 ５ 発光層 ４,６,１５ Ｓi3Ｎ4膜 ７ ＳiＯ2膜 ８ 背面電極群 ９,１０,２０
絶縁層 １４ ＳiＯ2膜 １９ 積層膜1 Glass Substrate 2 Transparent Electrode Group 3,13 TaON Film 5 Light Emitting Layer 4,6,15 Si 3 N 4 Film 7 SiO 2 Film 8 Back Electrode Group 9, 10, 20
Insulating layer 14 SiO 2 film 19 Laminated film
Claims (8)
層を有し、上記電極層のうち少なくとも一方の電極層と
上記発光層との間に絶縁層を介在させた薄膜ＥＬ素子に
おいて、 上記絶縁層は、上記電極層側に配されたＴaＯＮ膜と、
上記発光層側に配されたＳi3Ｎ4膜またはＳiＯＮ膜とか
らなることを特徴とする薄膜ＥＬ素子。1. A thin film EL device comprising a light emitting layer and a pair of electrode layers sandwiching the light emitting layer, wherein an insulating layer is interposed between at least one of the electrode layers and the light emitting layer. The insulating layer is a TaON film disposed on the electrode layer side,
A thin-film EL device comprising a Si 3 N 4 film or a SiON film arranged on the light emitting layer side.
て、 上記ＴaＯＮ膜の厚さが１０００Å乃至６０００Åであ
り、上記Ｓi3Ｎ4膜またはＳiＯＮ膜の厚さが１００Å乃
至１０００Åであることを特徴とする薄膜ＥＬ素子。2. The thin film EL device according to claim 1, wherein the TaON film has a thickness of 1000Å to 6000Å, and the Si 3 N 4 film or the SiON film has a thickness of 100Å to 1000Å. Thin film EL device.
層を有し、上記電極層のうち少なくとも一方の電極層と
上記発光層との間に絶縁層を介在させた薄膜ＥＬ素子に
おいて、 上記絶縁層は、ＴaＯＮ膜と、ＳiＯ2膜またはＳiＯＮ膜
とからなる単位層を複数重ねてなる積層膜を有すること
を特徴とする薄膜ＥＬ素子。3. A thin film EL device comprising a light emitting layer and a pair of electrode layers sandwiching the light emitting layer, wherein an insulating layer is interposed between at least one of the electrode layers and the light emitting layer. The thin film EL element is characterized in that the insulating layer has a laminated film formed by stacking a plurality of unit layers each including a TaON film and a SiO 2 film or a SiON film.
て、 上記絶縁層は、上記積層膜を上記電極層側に有し、上記
発光層側にＳi3Ｎ4膜またはＳiＯＮ膜を有することを特
徴とする薄膜ＥＬ素子。4. The thin film EL element according to claim 3, wherein the insulating layer has the laminated film on the electrode layer side, and has a Si 3 N 4 film or a SiON film on the light emitting layer side. Characteristic thin film EL device.
において、 上記単位層を構成するＳiＯ2膜またはＳiＯＮ膜と、Ｔa
ＯＮ膜との膜厚比ＳiＯ2／ＴaＯＮまたはＳiＯＮ／Ｔa
ＯＮの値が、１／１５乃至１０／１５の範囲内にあるこ
とを特徴とする薄膜ＥＬ素子。5. The thin film EL element according to claim 3 or 4, wherein the unit layer comprises a SiO 2 film or a SiON film, and Ta.
Thickness ratio with ON film: SiO 2 / TaON or SiON / Ta
A thin film EL device having an ON value in the range of 1/15 to 10/15.
ＥＬ素子において、上記単位層の厚さが３００Å以下で
あることを特徴とする薄膜ＥＬ素子。6. The thin film EL element according to claim 3, wherein the unit layer has a thickness of 300 Å or less.
ＥＬ素子において、上記ＴaＯＮ膜とＳiＯ2膜またはＳi
ＯＮ膜とからなる単位層を複数重ねてなる積層膜の厚さ
が１０００Å乃至６０００Åであることを特徴とする薄
膜ＥＬ素子。7. The thin film EL device according to claim 3, wherein the TaON film and the SiO 2 film or the Si film.
A thin film EL element, wherein a thickness of a laminated film formed by stacking a plurality of unit layers including an ON film is 1000Å to 6000Å.
て、上記Ｓｉ３Ｎ4膜またはＳiＯＮ膜の厚さが１００Å
乃至１０００Åであることを特徴とする薄膜ＥＬ素子。8. The thin film EL device according to claim 4, wherein the Si 3 N 4 film or the SiON film has a thickness of 100Å.
A thin film EL device characterized by a thickness of 1000 to 1000 Å.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4340163A JPH05347187A (en) | 1992-04-13 | 1992-12-21 | Thin film el element |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4-92665 | 1992-04-13 | ||
| JP9266592 | 1992-04-13 | ||
| JP4340163A JPH05347187A (en) | 1992-04-13 | 1992-12-21 | Thin film el element |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05347187A true JPH05347187A (en) | 1993-12-27 |
Family
ID=26434049
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4340163A Pending JPH05347187A (en) | 1992-04-13 | 1992-12-21 | Thin film el element |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05347187A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5789860A (en) * | 1995-08-11 | 1998-08-04 | Nippondenso Co., Ltd. | Dielectric thin film composition and thin-film EL device using same |
| KR20010066386A (en) * | 1999-12-31 | 2001-07-11 | 박종섭 | Method of forming gate electrode of Flash memory |
| US6740553B1 (en) * | 1999-06-25 | 2004-05-25 | Hyundai Electronics Industries Co., Ltd. | Capacitor for semiconductor memory device and method of manufacturing the same |
-
1992
- 1992-12-21 JP JP4340163A patent/JPH05347187A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5789860A (en) * | 1995-08-11 | 1998-08-04 | Nippondenso Co., Ltd. | Dielectric thin film composition and thin-film EL device using same |
| US6036823A (en) * | 1995-08-11 | 2000-03-14 | Denso Corporation | Dielectric thin film and thin-film EL device using same |
| US6740553B1 (en) * | 1999-06-25 | 2004-05-25 | Hyundai Electronics Industries Co., Ltd. | Capacitor for semiconductor memory device and method of manufacturing the same |
| KR20010066386A (en) * | 1999-12-31 | 2001-07-11 | 박종섭 | Method of forming gate electrode of Flash memory |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5003221A (en) | Electroluminescence element | |
| EP2518789B1 (en) | Method of manufacturing a light extraction substrate for an electroluminescent device | |
| WO1983004339A1 (en) | Thin film electric field light-emitting device | |
| US6036823A (en) | Dielectric thin film and thin-film EL device using same | |
| US5721562A (en) | Electroluminescent display device including a columnar crystal structure insulating film | |
| JPH05347187A (en) | Thin film el element | |
| US5667607A (en) | Process for fabricating electroluminescent device | |
| US4683044A (en) | Method of manufacturing an electroluminescent panel without any adverse influence on an underlying layer | |
| JP2686170B2 (en) | Thin film EL element | |
| JPH0458158B2 (en) | ||
| JPH03112089A (en) | Thin film el element | |
| KR960030748A (en) | White light-emitting electroluminescent device and manufacturing method thereof | |
| JPH0892548A (en) | Production of thin film electric field luminescent element | |
| JPH07235381A (en) | Thin film type electroluminescent element | |
| JPH02213090A (en) | Thin film el panel and manufacture thereof | |
| JPH02306585A (en) | Manufacture of thin film electroluminescence element | |
| JPH01124998A (en) | Thin el element | |
| JPH02301991A (en) | El display | |
| JPH03236195A (en) | Double-insulated thin film electroluminescence device | |
| JPH0745368A (en) | Film electroluminescent element | |
| JPH02306591A (en) | Manufacture of thin film electroluminescence element | |
| JPH01213991A (en) | Transparent electrode substrate and electroluminescence element utilizing same | |
| JPH02299196A (en) | Thin el device | |
| JPH0878162A (en) | Thin film electroluminescent element | |
| JPH11307247A (en) | Manufacture of thin film electroluminescent element |