Display device

Abstract

A display device includes a first thin film transistor of silicon type provided on a substrate, a first interlayer insulating film covering the first thin film transistor, an active pattern provided on the first interlayer insulating film and using indium-gallium-zinc oxide to a thickness, a gate insulating film covering the active pattern, a gate pattern arranged on the gate insulating film, and a second interlayer insulating film covering the gate pattern.

Description

TECHNICAL FIELD

[0001] The present application relates to a display device, and more particularly, to an organic light emitting display device and a method of fabricating the same. BACKGROUND

[0002] An organic light emitting display device is a display device that can emit light by itself, does not need a separate light source such as a backlight, and is easy to reduce thickness, and is suitable for implementation of a flexible display device, and thus its use is increasing.

[0003] Recently, in order to effectively drive pixels of an organic light emitting display device at low power, an organic light emitting display device including both a silicon thin film transistor and an oxide thin film transistor in each pixel is being developed. SUMMARY

[0004] An object of the present application is to provide a display device having improved reliability.

[0005] Another object of the present application is to provide a method of fabricating the display device.

[0006] To achieve the above object of the present application, a display device according to an exemplary embodiment of the present application includes a silicon first thin film transistor provided on a substrate, a first interlayer insulating film covering the first thin film transistor, an active pattern provided on the first interlayer insulating film and using indium-gallium-zinc oxide having a thickness of 1000 A to 2000 A, a gate insulating film covering the active pattern, a gate pattern disposed on the gate insulating film, and a second interlayer insulating film covering the gate pattern. to A thickness of the indium-gallium-zinc oxide is 1000 A to 2000 A.

[0007] According to an embodiment, the active pattern has a refractive index of 1.92 to 1.93 at a wavelength of 632 nm.

[0008] According to an embodiment, the active pattern has a density of higher than 6.3 g / cm 3 and lower than 6.6 g / cm 3 .

[0009] According to an embodiment, the lower first interlayer insulating film has a thickness of to the upper first interlayer insulating film has a thickness of to

[0010] According to an embodiment, the first interlayer insulating film includes a lower first interlayer insulating film including silicon nitride and an upper first interlayer insulating film including silicon oxide.

[0011] According to one embodiment, the NO2 spin density of the upper first interlayer insulating film is less than 5E+16 spins / cm. 3 .

[0012] According to one embodiment, the hydrogen concentration of the upper first interlayer insulating film is higher than 3.0E+20 atom / cm³. 3 And below 9.9E+20 atom / cm 3 .

[0013] According to one embodiment, the second interlayer insulating film includes a lower second interlayer insulating film comprising silicon oxide and an upper second interlayer insulating film comprising silicon nitride.

[0014] According to one embodiment, the lower second interlayer insulating film has to The thickness.

[0015] According to one embodiment, the upper second interlayer insulating film has to The thickness.

[0016] According to one embodiment, the hydrogen concentration within the upper second interlayer insulating film is 1.19E+22 atom / cm³. 3 Up to 1.28E+22atom / cm 3 .

[0017] According to one embodiment, the hydrogen concentration within the gate insulating film is higher than 3.0E+20 atom / cm³. 3 And below 1.2E+21 atom / cm 3 .

[0018] According to one embodiment, the NO2 spin density within the gate insulating film is less than 1.6E+19 spins / cm². 3 .

[0019] A display device according to an exemplary embodiment of the present invention includes: a first active pattern comprising polysilicon; a first gate insulating film covering the first active pattern; a first gate pattern disposed on the first gate insulating film; a second gate insulating film covering the first gate pattern; a second gate pattern disposed on the second gate insulating film; a first interlayer insulating film covering the second gate pattern; a second active pattern disposed on the first interlayer insulating film and comprising an oxide semiconductor material; a third gate insulating film covering the second active pattern; a third gate pattern disposed on the third gate insulating film; and a second interlayer insulating film covering the third gate pattern and comprising a lower second interlayer insulating film comprising silicon oxide and an upper second interlayer insulating film comprising silicon nitride.

[0020] According to an embodiment, the second active pattern includes indium-gallium-zinc oxide, and has to a thickness.

[0021] According to an embodiment, the second active pattern has a refractive index of 1.92 to 1.93 at a wavelength of 632 nm.

[0022] According to an embodiment, the first interlayer insulating film includes a lower first interlayer insulating film including silicon nitride and an upper first interlayer insulating film including silicon oxide.

[0023] According to an embodiment, the upper first interlayer insulating film has a hydrogen concentration higher than 3.0E+20 atom / cm 3 and lower than 9.9E+20 atom / cm 3 .

[0024] According to an embodiment, the upper second interlayer insulating film has to a thickness.

[0025] According to an embodiment, the third gate pattern includes a titanium film pattern and a molybdenum film pattern.

[0026] According to an exemplary embodiment of the present application, the second thin film transistor can have higher reliability and have a target threshold voltage. Also, for the display device, the second thin film transistor has lower off-state current. Thus, when the display device maintains an image, it can have lower off-state current, so that power consumption of the display device can be significantly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a circuit diagram showing a unit pixel of a display device.

[0028] Figure 2 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present application.

[0029] Figure 3 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present application.

[0030] Figure 4 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present application.

[0031] Figure 5 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present application.

[0032] Figures 6 to 16is a cross-sectional view illustrating a manufacturing method of an organic light emitting display device according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] Hereinafter, a display device and a manufacturing method of a display device according to exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. In the drawings, the same or similar components are designated by the same or similar reference numerals.

[0034] Figure 1 is an equivalent circuit diagram of a unit pixel of a display device. Figure 2 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present application.

[0035] Referring to Figure 1 , a unit pixel of a display device can include a plurality of thin film transistors T1 to T7, a capacitor C, and an organic light emitting diode LE. The thin film transistors T1 to T7 can be connected to a wiring such as a gate line, a data line, a driving voltage line, or the like.

[0036] The thin film transistors T1 to T7 can include a driving thin film transistor that controls the organic light emitting diode, first thin film transistors T1, T2, T5 to T7 that constitute a built-in circuit or the like, and second thin film transistors T3, T4 that are used to switch the driving thin film transistor.

[0037] Although Figure 1 a case in which a unit pixel includes five first thin film transistors T1, T2, T5 to T7, two second thin film transistors T3, T4, and one capacitor is illustrated in FIG. 1, the number of first thin film transistors, second thin film transistors, and capacitors is not limited thereto in the present application.

[0038] The first thin film transistors T1, T2, T5 to T7 can be formed to be stably driven under a bias stress. In an exemplary embodiment, the first thin film transistors T1, T2, T5 to T7 can be silicon thin film transistors.

[0039] On the contrary, since the second thin film transistors T3, T4 are provided as switching elements, the second thin film transistors T3, T4 can be formed to have a very small off current in an off state and to have a target threshold voltage. In an exemplary embodiment, the second thin film transistors T3, T4 can be oxide thin film transistors.

[0040] The organic light emitting diode LE can include a light emitting layer and a lower electrode and an upper electrode that face each other with the light emitting layer interposed therebetween. The light emitting layer can emit light according to an output signal of a part of the first thin film transistors (for example, the first thin film transistors T6 to T7), thereby displaying an image.

[0041] The capacitor can be connected between a gate pattern and a source electrode of a part of the first thin film transistor (for example, the first thin film transistor T1), and charges and holds a data signal input to the gate pattern of the first thin film transistor T1.

[0042] Hereinafter, a cross-sectional structure of a display device according to an embodiment of the present application will be described with reference to the accompanying drawings. Figure 2

[0043] Figure 2 Elements included in a unit pixel of a display device are illustrated, and each unit pixel can include a first thin film transistor, a second thin film transistor, and a capacitor.

[0044] Referring to Figure 2 A buffer film 102 is provided on a base substrate 100. A first active pattern 104 is provided on the buffer film 102.

[0045] The base substrate 100 can include glass, quartz, silicon, a polymer resin, or the like. For example, the polymer resin can include polyethylene terephthalate, polyethylene naphthalate, polyether ketone, polycarbonate, polyarylate, polyether sulfone, polyimide, or the like.

[0046] The buffer film 102 can include an inorganic substance such as an oxide or a nitride. According to an embodiment, the buffer film 102 can have a multi-layer structure including a lower film containing silicon nitride and an upper film containing silicon oxide.

[0047] The first active pattern 104 can include silicon. For example, the first active pattern 104 can include polysilicon.

[0048] The first active pattern 104 can include a first channel region 104b and first source and drain regions 104a disposed on both sides of the first channel region 104b, respectively. The first source / drain regions 104a can be doped with impurities.

[0049] A first gate insulating film 106 can be provided on the buffer film 102 and the first active pattern 104. The first gate insulating film 106 can cover the buffer film 102 and the first active pattern 104.

[0050] The first gate insulating film 106 can include, for example, silicon oxide (SiO x ), silicon nitride (SiN x ​silicon nitride, silicon oxynitride, or a combination thereof. In some embodiments, the first gate insulating film 106 can also include an insulating metal oxide such as aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, titanium oxide, or the like.

[0051] A first gate pattern 108 can be provided over the first gate insulating film 106. The first gate pattern 108 can be arranged to overlap the first channel region 104b of the first active pattern 104. The first gate pattern 108 can include a metal such as aluminum (Al), silver (Ag), chromium (Cr), titanium (Ti), tantalum (Ta), molybdenum (Mo), or the like, an alloy thereof, a nitride thereof, a conductive metal oxide, a transparent conductive substance, or the like. As an example, the first gate pattern 108 can have a layered structure of a titanium film pattern and a molybdenum film pattern.

[0052] The first active pattern 104 can be provided as an active region of the first thin film transistor. Thus, a layered structure of the first active pattern 104, the first gate insulating film 106, and the first gate pattern 108 can be provided as one of the first thin film transistor.

[0053] A second gate insulating film 110 can be provided over the first gate insulating film 106 and the first gate pattern 108. The second gate insulating film 110 can cover the first gate insulating film 106 and the first gate pattern 108. The second gate insulating film 110 can include silicon oxide, silicon nitride, silicon oxynitride, or the like. Since the second gate insulating film 110 functions as a dielectric film of a capacitor, it is preferable to have a high dielectric constant in order to increase the storage capacity. For example, the second gate insulating film 110 can use silicon nitride having a higher dielectric constant than silicon oxide.

[0054] A second gate pattern 112 can be provided over the second gate insulating film 110. The second gate pattern 112 can overlap the first gate pattern 108. The second gate pattern 112 can include a metal such as aluminum (Al), silver (Ag), chromium (Cr), titanium (Ti), tantalum (Ta), molybdenum (Mo), or the like, an alloy thereof, a nitride thereof, a conductive metal oxide, a transparent conductive substance, or the like. As an example, the second gate insulating film 110 can have a layered structure of a titanium film pattern and a molybdenum film pattern.

[0055] A layered structure of the first gate pattern 108, the second gate insulating film 110, and the second gate pattern 112 can be provided as a capacitor.

[0056] A first interlayer insulating film 120 can be provided over the second gate insulating film 110 and the second gate pattern 112. The first interlayer insulating film 120 can cover the second gate insulating film 110 and the second gate pattern 112. The first interlayer insulating film 120 can include silicon oxide, silicon nitride, silicon oxynitride, or the like. In an exemplary embodiment, the first interlayer insulating film 120 can be formed as a single layer including a single substance.

[0057] A second active pattern 130 can be provided over the first interlayer insulating film 120. The second active pattern 130 can be provided as an active region of the second thin film transistor.

[0058] The second thin film transistor can be configured to have high reliability and to have a target threshold voltage. Hereinafter, a case where the second thin film transistor has a target threshold voltage of -3.5 V to +2 V will be described, and a stacked structure of the second thin film transistor suitable for this will be described.

[0059] The second active pattern 130 can include an oxide semiconductor substance. For example, the second active pattern 130 can include an oxide containing indium (In), zinc (Zn), gallium (Ga), tin (Sn), titanium (Ti), aluminum (Al), hafnium (Hf), zirconium (Zr), magnesium (Mg), or the like. The second active pattern 130 can include a binary compound (AB x ), a ternary compound (AB x C y ), a quaternary compound (AB x C y D z ), or the like.

[0060] In the present embodiment, a case where indium-gallium-zinc oxide (IGZO) is used for the second active pattern 130 will be described.

[0061] In a case where indium-gallium-zinc oxide (IGZO) is used as the second active pattern 130, the electrical characteristics of the second thin film transistor can differ depending on the thickness and the physical properties of the second active pattern 130, and in particular, the threshold voltage of the second thin film transistor can vary.

[0062] In a case where the thickness T of the second active pattern 130 is reduced, the threshold voltage of the second thin film transistor can increase. Therefore, the thickness T of the second active pattern 130 can be adjusted so that the second thin film transistor has the target threshold voltage. In an exemplary embodiment, the second active pattern 130 can have a thickness of 10 nm to 100 nm.

[0063] ​​For the second active pattern 130, the density and the refractive index of the film can vary depending on the oxygen content contained in the film. Also, the threshold voltage of the second thin film transistor can vary depending on the oxygen contained in the second active pattern 130. Specifically, if the oxygen contained in the second active pattern 130 increases, the threshold voltage can increase, and if the oxygen contained in the second active pattern 130 decreases, the threshold voltage can decrease. Therefore, the density and the refractive index of the second active pattern 130 can be adjusted so that the second thin film transistor can have the target threshold voltage.

[0064] In an exemplary embodiment, the density of the second active pattern 130 can be, for example, higher than 6.3 g / cm 3 and lower than 6.6 g / cm 3 .

[0065] If the oxygen contained in the second active pattern 130 increases, the refractive index can increase. In an exemplary embodiment, the refractive index of the second active pattern 130 can be 1.92 to 1.93 when measured at a wavelength of 632 nm. If the refractive index of the second active pattern 130 is lower than 1.92, the threshold voltage can be significantly lower than the target threshold voltage, and if it is higher than 1.93, the threshold voltage can be significantly higher than the target threshold voltage.

[0066] The second active pattern 130 can include a second channel region 130b and a second source region 130a and a second drain region 130a formed on both sides of the second channel region 130b, respectively.

[0067] A third gate insulating film 132 can be provided on the first interlayer insulating film 120 and the second active pattern 130. The third gate insulating film 132 can cover the first interlayer insulating film 120 and the second active pattern 130.

[0068] The third gate insulating film 132 can include silicon oxide, silicon nitride, silicon oxynitride, or the like. The physical properties of the third gate insulating film 132 can affect the characteristics of the second thin film transistor.

[0069] In the present embodiment, the third gate insulating film 132 is described as being formed using a silicon oxide film.

[0070] If the hydrogen contained in the third gate insulating film 132 increases, the threshold voltage of the second thin film transistor can significantly decrease to have a negative value. Therefore, in order for the second thin film transistor to have the target threshold voltage, it is preferable that the hydrogen concentration in the third gate insulating film 132 be low. Specifically, the hydrogen concentration in the third gate insulating film 132 can be, for example, higher than 3.0E+20 atom / cm3 And below 1.2E+21 atom / cm 3 .

[0071] Furthermore, when trap sites are added within the silicon oxide film that forms the third gate insulating film 132, the threshold voltage of the second thin-film transistor can change according to stress. Therefore, to ensure the reliability of the second thin-film transistor, it is preferable to reduce the number of trap sites within the third gate insulating film 132. Specifically, the number of trap sites within the third gate insulating film 132 can be quantified by the NO2 spin density, which should be as low as possible. The NO2 spin density can represent the defect density of NO2 states contained in the film. For example, the NO2 spin density within the third gate insulating film 132 can be lower than 1.6E+19 spins / cm. 3 .

[0072] A third gate pattern 134 may be provided on the third gate insulating film 132. The third gate pattern 134 may be arranged to overlap with the second channel region 130b of the second active pattern 130. The third gate pattern 134 may include metals such as aluminum (Al), silver (Ag), chromium (Cr), titanium (Ti), tantalum (Ta), molybdenum (Mo), as well as their alloys, their nitrides, conductive metal oxides, transparent conductive materials, etc.

[0073] In an exemplary embodiment, the third gate pattern 134 may have a stacked structure of a titanium film pattern 134a and a molybdenum film pattern 134b. In this case, the titanium film pattern 134a can be used as a metal barrier film, and the molybdenum film pattern 134b can be used as a gate electrode.

[0074] In order to configure the titanium film pattern 134a as a metal barrier film, the titanium film pattern 134a preferably has The thickness is as described above. As an example, the titanium film pattern 134a may have... to The thickness.

[0075] The third gate pattern 134 can be arranged to overlap with the second channel region 130b. Therefore, the third gate pattern 134 can prevent hydrogen contained in the upper second interlayer insulating film 140 from diffusing into the second channel region 130b. For this purpose, in order to prevent hydrogen diffusion and have low resistance, the molybdenum film pattern 134b preferably has... The thickness is as described above. As an example, the molybdenum film pattern 134b can have... to The thickness.

[0076] The second active pattern 130, the third gate insulating film 132, and the third gate pattern 134 can be configured as one of the second thin-film transistors.

[0077] A second interlayer insulating film 140 may be provided on the first interlayer insulating film 120 and the third gate pattern 134. The second interlayer insulating film 140 may cover the first interlayer insulating film 120 and the third gate pattern 134. The second interlayer insulating film 140 may include silicon oxide, silicon nitride, silicon oxide nitride, etc. In an exemplary embodiment, the second interlayer insulating film 140 may be a monolayer formed using a single material.

[0078] A first source / drain pattern 150 may be provided, which penetrates the second interlayer insulating film 140, the third gate insulating film 132, the first interlayer insulating film 120, the second gate insulating film 110, and the first gate insulating film 106, and contacts the first source region 104a and the first drain region 104a respectively. The first source / drain pattern 150 may be disposed on the second interlayer insulating film 140. Therefore, the first source / drain pattern 150 may be electrically connected to the first source region 104a and the first drain region 104a respectively.

[0079] A second source / drain pattern 152 may be provided, which penetrates the second interlayer insulating film 140 and the third gate insulating film 132 and contacts the second source region 130a and the second drain region 130a, respectively. Furthermore, the second source / drain pattern 152 may be disposed on the second interlayer insulating film 140. Therefore, the second source / drain pattern 152 can be electrically connected to the second source region 130a and the second drain region 130a, respectively.

[0080] A first insulating film 154 covering the first source / drain pattern 150 and the second source / drain pattern 152 may be provided on the second interlayer insulating film 140. The first insulating film 154 may include, for example, organic insulating materials such as phenolic resin, acrylic resin, polyimide resin, polyamide resin, silicone resin, and epoxy resin.

[0081] A lower electrode 156 of an organic light-emitting diode may be provided on the first insulating film 154. A lower portion of the lower electrode 156 may penetrate the first insulating film 154 and be connected to the first source / drain pattern 150.

[0082] A pixel defining film 158 may be provided on the lower electrode 156. The pixel defining film 158 has an opening that exposes at least a portion of the lower electrode 156. For example, the pixel defining film 158 may include an organic insulating material.

[0083] A light-emitting layer 160 is formed on the lower electrode 156. The light-emitting layer 160 may have a single-layer or multi-layer structure, including at least one of the functional layers such as a hole injection layer, a hole transport layer, an organic light-emitting layer, an electron transport layer, and an electron injection layer. The light-emitting layer 160 may include low-molecular-weight organic compounds or high-molecular-weight organic compounds.

[0084] An upper electrode 162 may be provided on the light-emitting layer 160. In an exemplary embodiment, the upper electrode 162 may extend continuously across multiple pixels in the display area. According to one embodiment, a cover layer and a blocking layer may also be formed on the upper electrode 162.

[0085] The lower electrode 156, the light-emitting layer 160, and the upper electrode 162 can be configured as organic light-emitting diodes 164.

[0086] According to one embodiment, an encapsulation layer 170 may be provided on the organic light-emitting diode 164. The encapsulation layer 170 may have a stacked structure of inorganic and organic layers.

[0087] As described above, based on the thickness and properties of the second active pattern 130, the second thin-film transistor can have a target threshold voltage. Therefore, the second thin-film transistor can stably perform switching operations, and leakage current can be significantly reduced.

[0088] Therefore, the organic light-emitting display device can have a low cutoff leakage current while holding the image, thereby significantly reducing the power consumption of the organic light-emitting display device.

[0089] Figure 3 This is a cross-sectional view of an organic light-emitting display device according to an embodiment of the present invention.

[0090] In addition to the first interlayer insulating film arranged below the second active pattern Figure 3 The organic light-emitting display device shown can have the same characteristics as... Figure 2 The organic light-emitting display devices shown have essentially the same configuration.

[0091] Reference Figure 3 The first interlayer insulating film 120 may include a lower first interlayer insulating film 120a and an upper first interlayer insulating film 120b. The lower first interlayer insulating film 120a may include silicon nitride. And the upper first interlayer insulating film 120b may include silicon oxide. Therefore, the first interlayer insulating film 120 may have a structure of silicon nitride and silicon oxide stacked.

[0092] During the etching process used to form the second gate pattern 112, fluoride ions may remain on the upper surface of the second gate insulating film 110. The lower first interlayer insulating film 120a can be used as a barrier film to suppress the upward diffusion of the aforementioned residual fluoride ions. That is, the lower first interlayer insulating film 120a can suppress the diffusion of the fluoride ions to the second active pattern 130.

[0093] If the lower first interlayer insulating film 120a is compared to If the film is thinner, the effect of preventing fluoride ion diffusion is reduced, and therefore it may not be preferred. Furthermore, if the lower first interlayer insulating film 120a is thinner than... If the thickness is increased, the overall thickness of the first interlayer insulating film 120 can increase, and the parasitic capacitance will also increase. Therefore, the lower first interlayer insulating film 120a can be thicker than... Thick. Preferably, the lower first interlayer insulating film 120a may have... to The thickness.

[0094] The upper first interlayer insulating film 120b contacts the lower part of the second active pattern 130, thereby influencing the characteristics of the second thin-film transistor. The upper first interlayer insulating film 120b can be formed at least as... Thick. For example, the upper first interlayer insulating film 120b may have to The thickness.

[0095] With an increase in hydrogen concentration within the upper first interlayer insulating film 120b, the threshold voltage of the second thin-film transistor can significantly decrease and become negative. Therefore, to achieve the target threshold voltage in the second thin-film transistor, it is preferable that the hydrogen concentration within the upper first interlayer insulating film 120b is low. Specifically, the hydrogen concentration within the upper first interlayer insulating film 120b can, for example, be higher than 3.0E+20 atom / cm³. 3 And below 9.9E+20 atom / cm 3 .

[0096] Furthermore, when trapping sites are added within the upper first interlayer insulating film 120b, the threshold voltage of the second thin-film transistor can change according to stress. Therefore, to ensure the reliability of the second thin-film transistor, it is preferable to reduce the number of trapping sites within the upper first interlayer insulating film 120b. Specifically, the number of trapping sites within the upper first interlayer insulating film 120b can be quantified by the NO2 spin density, and a lower NO2 spin density is better. For example, the NO2 spin density within the upper first interlayer insulating film 120b can be lower than 5E+16 spins / cm. 3 .

[0097] Furthermore, preferably, the moisture adhesion of the upper first interlayer insulating film 120b is reduced.

[0098] As described above, the threshold voltage of the second thin-film transistor can vary according to the stacked structure of the first interlayer insulating film 120, thereby allowing the second thin-film transistor to have a target threshold voltage. Therefore, the second thin-film transistor can stably perform switching operations, and leakage current can be significantly reduced.

[0099] In addition, although in reference Figure 2 In the description, the second active pattern 130 uses indium gallium zinc oxide (IGZO), but the material used as the second active pattern 130 is not limited to this. For example, the second active pattern 130 may include indium tin zinc oxide (ITZO), gallium zinc oxide (GaZnO), etc. x O y Indium zinc oxide (IZO), zinc magnesium oxide (ZnMg) x O y ), Zinc tin oxide (ZnSn) x O y ), Zinc zirconium oxide (ZnZr) x O y ), zinc oxide (ZnO) x Gallium oxide (GaO) x ), tin oxide (SnO x Indium oxide (InO) x Indium-gallium-hafnium oxide (IGHO), tin-aluminum-zinc oxide (TAZO), indium-gallium-tin oxide (IGSO), etc. These substances can be used alone or in combination with each other. In one embodiment, lithium (Li), sodium (Na), manganese (Mn), nickel (Ni), palladium (Pd), copper (Cu), carbon (C), nitrogen (N), phosphorus (P), titanium (Ti), zirconium (Zr), vanadium (V), ruthenium (Ru), germanium (Ge), tin (Sn), fluorine (F), etc., can also be doped into the above-mentioned semiconductor oxides.

[0100] Figure 4 This is a cross-sectional view of an organic light-emitting display device according to an embodiment of the present invention.

[0101] In addition to the second interlayer insulating film formed on the third gate pattern Figure 4 The organic light-emitting display device shown can have the same characteristics as... Figure 2 The organic light-emitting display devices shown have essentially the same configuration.

[0102] Reference Figure 4 The second interlayer insulating film 140 may include a lower second interlayer insulating film 140a and an upper second interlayer insulating film 140b. The lower second interlayer insulating film 140a may include silicon oxide. The upper second interlayer insulating film 140b may include silicon nitride. Therefore, the second interlayer insulating film 140 may have a structure of silicon oxide and silicon nitride stacked.

[0103] The lower second interlayer insulating film 140a comprises silicon oxide, which has a lower dielectric constant compared to silicon nitride. Therefore, by equipping the lower second interlayer insulating film 140a, the parasitic capacitance generated by the entire second interlayer insulating film 140 can be reduced. The lower second interlayer insulating film 140a may have... The thickness is as described above. For example, the lower second interlayer insulating film 140a may have the following thickness: to The thickness.

[0104] The silicon nitride used as the upper second interlayer insulating film 140b can contain hydrogen internally. This hydrogen can diffuse into the source / drain region 130a of the second active pattern 130, thereby reducing the source / drain resistance. Therefore, the on-state current of the second thin-film transistor can be increased. At this time, by providing the third gate pattern 134, the hydrogen can hardly diffuse into the third gate insulating film 132 below the third gate pattern 134. Therefore, the hydrogen concentration within the third gate insulating film 132 can remain unchanged.

[0105] When the thickness of the upper second interlayer insulating film 140b is small, the hydrogen may not diffuse sufficiently into the source / drain region 130a. Therefore, the upper second interlayer insulating film 140b may have... The thickness mentioned above. As the thickness of the upper second interlayer insulating film 140b increases, the parasitic capacitance can increase. Therefore, the upper second interlayer insulating film 140b can have... to The thickness of the second interlayer insulating film 140a is shown in the figures as being thicker than that of the upper second interlayer insulating film 140b, but this is not a limitation.

[0106] Furthermore, the hydrogen concentration within the upper second interlayer insulating film 140b can be approximately 1.19E+22 atom / cm³. 3 Up to 1.28E+22atom / cm 3 .

[0107] As described above, the threshold voltage of the second thin-film transistor can vary according to the stacked structure of the second interlayer insulating film 140, thereby allowing the second thin-film transistor to have a target threshold voltage. Therefore, the second thin-film transistor can stably perform switching operations, and leakage current can be significantly reduced.

[0108] In addition, although in reference Figure 2 In the description, the second active pattern 130 uses indium gallium zinc oxide (IGZO), but the material used as the second active pattern 130 is not limited to this.

[0109] Figure 5 This is a cross-sectional view of an organic light-emitting display device according to an embodiment of the present invention.

[0110] Apart from the first interlayer insulating film and the second interlayer insulating film Figure 5 The organic light-emitting display device shown can have the same characteristics as... Figure 2 The organic light-emitting display devices shown have essentially the same configuration.

[0111] Reference Figure 5 The first interlayer insulating film 120 may include a lower first interlayer insulating film 120a and an upper first interlayer insulating film 120b. The lower first interlayer insulating film 120a may include silicon nitride.

[0112] Furthermore, the upper first interlayer insulating film 120b may include silicon oxide. Therefore, the first interlayer insulating film 120 may have a structure of silicon nitride and silicon oxide layers stacked together.

[0113] The lower first interlayer insulating film 120a and the upper first interlayer insulating film 120b can be respectively connected to a reference. Figure 3 The lower first interlayer insulating film 120a and the upper first interlayer insulating film 120b described herein are the same.

[0114] Furthermore, the second interlayer insulating film 140 may include a lower second interlayer insulating film 140a and an upper second interlayer insulating film 140b. The lower second interlayer insulating film 140a may include silicon oxide. And the upper second interlayer insulating film 140b may include silicon nitride. Therefore, the second interlayer insulating film 140 may have a structure of silicon oxide and silicon nitride stacked.

[0115] The lower second interlayer insulating film 140a and the upper second interlayer insulating film 140b can be respectively connected to a reference. Figure 4 The lower second interlayer insulating film 140a and the upper second interlayer insulating film 140b are the same as those described.

[0116] As described above, by optimizing the second active pattern 130, the first interlayer insulating film 120, and the second interlayer insulating film 140, the second thin-film transistor can have a target threshold voltage. Therefore, the second thin-film transistor can stably perform switching operations, and leakage current can be significantly reduced.

[0117] Figures 6 to 16 This is a cross-sectional view illustrating a method for manufacturing an organic light-emitting display device according to an embodiment of the present invention.

[0118] Reference Figure 6 A buffer film 102 is formed on the base substrate 100. The buffer film 102 can reduce or block the penetration of foreign matter, moisture or external air from the lower part of the base substrate 100, and the buffer film 102 can have a flat upper surface.

[0119] A first active pattern 104 is formed on the buffer film 102.

[0120] To form the first active pattern 104, a polycrystalline silicon film can be formed by crystallizing the amorphous silicon film after it has been formed. The first active pattern 104 can be formed by patterning the polycrystalline silicon film using a photolithography process.

[0121] For example, the amorphous silicon film can be formed by low-pressure chemical vapor deposition (LPCVD), plasma-enhanced chemical vapor deposition (PECVD), etc. The amorphous silicon film can be crystallized by excimer laser annealing, sequential lateral solidification, etc.

[0122] Reference Figure 7 A first gate insulating film 106 is formed covering the buffer film 102 and the first active pattern 104. A first gate film is formed on the first gate insulating film 106 and patterned thereon to form a first gate pattern 108.

[0123] Subsequently, impurities are doped into the portions of the first active pattern 104 that do not overlap with the first gate pattern 108. Therefore, a first source region 104a and a first drain region 104a doped with impurities are formed in the first active pattern 104. For example, the impurities can be P-type impurities such as boron. Furthermore, the portions of the first active pattern 104 that overlap with the first gate pattern 108 can be configured as a first channel region 104b.

[0124] The first thin-film transistor, comprising the first active pattern 104, the first gate insulating film 106, and the first gate pattern 108, can be formed through the above process.

[0125] Reference Figure 8 A second gate insulating film 110 is formed on the first gate insulating film 106 and the first gate pattern 108. A second gate film is formed on the second gate insulating film 110 and patterned thereon to form a second gate pattern 112.

[0126] The second gate film can be formed by stacking metal films using a physical vapor deposition process. Furthermore, a photoresist pattern can be formed on the metal film and used as an etching mask to etch the metal film to expose the second gate insulating film 110, thereby forming the second gate pattern 112.

[0127] According to an exemplary embodiment, the metal can be etched using a plasma containing an etching gas comprising a fluorine compound. For example, the fluorine compound may include SiF4, CF4, C3F8, C2F6, CHF3, SF6, or combinations thereof.

[0128] Additionally, during the etching process of the metal, fluoride ions generated from the etching gas may remain on the surface of the second gate insulating film 110 or combine with the insulating material (e.g., silicon nitride) of the second gate insulating film 110.

[0129] In subsequent processes, the fluoride ions can diffuse into the first interlayer insulating film and the second active pattern disposed on the second gate insulating film 110. In particular, if the fluoride ions diffuse into the second active pattern, the threshold voltage of the second thin-film transistor may decrease, and its electrical characteristics may deteriorate. Therefore, preferably, the first interlayer insulating film disposed on the second gate insulating film 110 has a structure capable of suppressing the diffusion of the fluoride ions.

[0130] As the second gate pattern 112 is formed, a capacitor comprising the first gate pattern 108, the second gate insulating film 110, and the second gate pattern 112 can be formed.

[0131] Reference Figure 9 A first interlayer insulating film 120 is formed on the second gate insulating film 110 and the second gate pattern 112.

[0132] In an exemplary embodiment, the first interlayer insulating film 120 may include a lower first interlayer insulating film 120a and an upper first interlayer insulating film 120b. The lower first interlayer insulating film 120a may include silicon nitride. And the upper first interlayer insulating film 120b may include silicon oxide.

[0133] The lower first interlayer insulating film 120a and the upper first interlayer insulating film 120b can be formed to have a reference Figure 3 The characteristics described.

[0134] The lower first interlayer insulating film 120a and the upper first interlayer insulating film 120b can be formed by chemical vapor deposition.

[0135] In the deposition process of the lower first interlayer insulating film 120a, the deposition gas may include a silicon source gas and a nitrogen source gas. The lower first interlayer insulating film 120a has... to The thickness of the insulation film is such that it can suppress the upward diffusion of fluoride ions. At this point, the hydrogen concentration within the lower first interlayer insulating film 120a has little correlation with the blocking effect and can therefore be disregarded.

[0136] In the deposition process of the upper first interlayer insulating film 120b, the deposition gas can be a silicon source gas and an oxygen source gas, wherein the silicon source gas may include hydrogen. Therefore, the hydrogen concentration within the silicon oxide can be adjusted by regulating process conditions such as the flow rate of the silicon source gas and the deposition power. For example, the silicon source gas may include SiH4 and SiH2C. l2 Si2H6, etc.

[0137] In some exemplary embodiments, the first interlayer insulating film 120 may be formed as a single layer comprising one of silicon oxide, silicon nitride, and silicon oxynitride. In this case, it can be manufactured by performing subsequent processes. Figure 2 or Figure 4 The organic light-emitting display device shown.

[0138] Reference Figure 10 A second active pattern 130 is formed on the first interlayer insulating film 120. The second active pattern 130 can be formed by forming a second active film and patterning it using a photolithography process.

[0139] The second active film can be formed by a physical vapor deposition process (e.g., sputtering process).

[0140] In an exemplary embodiment, the second active film may be formed using indium gallium zinc oxide (IGZO). In this case, the second active film may have the same characteristics as the reference film.Figure 2 The second active pattern has the same characteristics. That is, the second active film can have... to The thickness. Furthermore, the density of the second active membrane can, for example, be higher than 6.3 g / cm³. 3 And below 6.63 g / cm 3 When measured at a wavelength of 632 nm, the refractive index of the second active film can be between 1.92 and 1.93.

[0141] The density and refractive index of the second active film can be adjusted by the process conditions during its formation. In particular, during the deposition process of the second active film, the density and refractive index can be adjusted by regulating the oxygen partial pressure.

[0142] If the oxygen partial pressure increases during the deposition process, the oxygen content in the second active film increases, thus increasing the threshold voltage of the second thin-film transistor. Conversely, if the oxygen partial pressure decreases during the deposition process, the oxygen content in the second active film decreases, thus decreasing the threshold voltage of the second thin-film transistor. Therefore, to achieve the target threshold voltage for the second thin-film transistor, the oxygen partial pressure during the deposition process of the second active film can be between 20% and 80%.

[0143] In an exemplary embodiment, for the deposition process of the second active film, an indium-gallium-zinc target of 1:1:1 can be used. The deposition process of the second active film can be performed at a power of 40 kW to 60 kW, a pressure of 0.3 Pa to 0.5 Pa, and a temperature of 10 °C to 200 °C. However, the deposition process conditions are not limited to these.

[0144] Reference Figure 11 A third gate insulating film 132 is formed on the first interlayer insulating film 120 and the second active pattern 130.

[0145] The third gate insulating film 132 may include silicon oxide, silicon nitride, silicon oxide nitride, etc. The third gate insulating film 132 may be formed by chemical vapor deposition.

[0146] In an exemplary embodiment, the third gate insulating film 132 may have the same characteristics as the referenced one. Figure 2 The third gate insulating film 132 has the same characteristics. That is, the third gate insulating film 132 can be formed using silicon oxide, and the hydrogen concentration inside the film can be higher than 3.0E+20 atom / cm³. 3 And below 1.2E+21 atom / cm 3 Furthermore, the NO2 spin density within the membrane can, for example, be lower than 1.6E+19 spins / cm².3 .

[0147] In the deposition process of the third gate insulating film 132, the deposition gas can be a silicon source gas and an oxygen source gas, and the silicon source gas may include hydrogen. Therefore, the hydrogen concentration in the silicon oxide can be adjusted by regulating process conditions such as the flow rate of the silicon source gas and the power during deposition.

[0148] Reference Figure 12 A third gate film is formed on the third gate insulating film 132 and patterned thereon to form a third gate pattern 134.

[0149] The third gate film can be formed by stacking metal films using a physical vapor deposition process. Furthermore, a photoresist pattern can be formed on the metal film and used as an etching mask to etch the metal film to expose the third gate insulating film 132, thereby forming the third gate pattern 134.

[0150] In an exemplary embodiment, the third gate pattern 134 can be formed as a stacked structure of titanium film pattern 134a and molybdenum film pattern 134b. In this case, the third gate film can be formed by sequentially forming a titanium film and a molybdenum film on the third gate insulating film 132. The titanium film can be formed with... The thickness mentioned above, for example, to The thickness of the molybdenum film. Furthermore, to prevent hydrogen diffusion and to have low electrical resistance, the molybdenum film can be formed with... The above thickness, for example to The thickness. However, the stacked structure of the third gate pattern 134 is not limited to this.

[0151] In the second active pattern 130, the portion overlapping with the third gate pattern 134 can serve as the second channel region 130b. Furthermore, in the second active pattern 130, the portion not overlapping with the third gate pattern 134 can serve as the second source / drain region 130a.

[0152] Reference Figure 13 A second interlayer insulating film 140 is formed covering the third gate insulating film 132 and the third gate pattern 134.

[0153] In an exemplary embodiment, the second interlayer insulating film 140 may include a lower second interlayer insulating film 140a and an upper second interlayer insulating film 140b. The lower second interlayer insulating film 140a may include silicon oxide. The upper second interlayer insulating film 140b may include silicon nitride. The lower second interlayer insulating film 140a and the upper second interlayer insulating film 140b may be formed by a chemical vapor deposition process. The lower second interlayer insulating film 140a and the upper second interlayer insulating film 140b may be formed with a reference... Figure 5 The aforementioned characteristics.

[0154] The lower second interlayer insulating film 140a can be formed to have The thickness mentioned above, for example, to The thickness can be determined without considering other physical properties.

[0155] In the deposition process of the upper second interlayer insulating film 140b, a silicon source gas and a nitrogen source gas can be used for deposition. In this case, the silicon source gas and the nitrogen source gas can each include hydrogen. For example, the silicon source gas can include SiH4 and SiH2C. l2 The source gas can include nitrogen gas such as Si2H6, and the nitrogen source gas can include NH3. Therefore, the hydrogen concentration in the upper second interlayer insulating film 140b can be adjusted by regulating the flow rates of the nitrogen source gas and the silicon source gas.

[0156] Hydrogen within the upper second interlayer insulating film 140b can diffuse into the second source / drain region 130a of the second active pattern 130, thereby reducing the resistance of the second source / drain region 130a. Therefore, the on-state current of the second thin-film transistor can be increased. Furthermore, hydrogen can diffuse almost no further into the third gate insulating film 132 below the third gate pattern 134 and into the second channel region 130b. Therefore, the hydrogen concentration within the third gate insulating film 132 below the third gate pattern 134 can remain unchanged.

[0157] In some exemplary embodiments, the second interlayer insulating film 140 may be formed as a single layer comprising one of silicon oxide, silicon nitride, and silicon oxynitride. In this case, it can be manufactured by performing subsequent processes. Figure 2 or Figure 3 The organic light-emitting display device shown.

[0158] Reference Figure 14 The second interlayer insulating film 140, the third gate insulating film 132, the first interlayer insulating film 120, the second gate insulating film 110 and the first gate insulating film 106 are etched to form first contact holes that expose the first source / drain regions 104a.

[0159] Furthermore, the second interlayer insulating film 140 and the third gate insulating film 132 are etched to form a second contact hole that exposes the second source / drain region 130a.

[0160] Next, while filling the first and second contact holes, a metal film is formed on the second interlayer insulating film 140. By patterning the metal film, a first source / drain pattern 150 electrically connected to the first source region 104a and the first drain region 104a is formed. Furthermore, a second source / drain pattern 152 electrically connected to the second source region 130a and the second drain region 130a is formed.

[0161] Reference Figure 15 A first insulating film 154 is formed covering the second interlayer insulating film 140, the first source / drain pattern 150, and the second source / drain pattern 152.

[0162] A photolithography process is performed on the first insulating film 154 to form contact holes that expose the first source / drain pattern 150. Simultaneously, a lower electrode film is formed on the first insulating film 154 while filling the contact holes, and the lower electrode film is patterned to form the lower electrode 156 of the organic light-emitting diode 200.

[0163] The lower electrode 156 can operate as an anode. For example, the lower electrode 156 can be formed as a transparent electrode or a reflective electrode, depending on the type of light emission. When the lower electrode 156 is formed as a transparent electrode, it may include indium tin oxide, indium zinc oxide, zinc tin oxide, indium oxide, zinc oxide, tin oxide, etc. When the lower electrode 156 is formed as a reflective electrode, it may include gold (Au), silver (Ag), aluminum (Al), copper (Cu), nickel (Ni), platinum (Pt), magnesium (Mg), chromium (Cr), tungsten (W), molybdenum (Mo), titanium (Ti), etc., and may also have a layered structure with the material used in the transparent electrode.

[0164] A pixel defining film 158 is formed on the first insulating film 154, having an opening that exposes at least a portion of the lower electrode 156. For example, the pixel defining film 158 may include an organic insulating material.

[0165] Reference Figure 16 A light-emitting layer 160 is formed on the lower electrode 156. For example, the light-emitting layer 160 can be formed by methods such as screen printing, inkjet printing, or deposition.

[0166] An upper electrode 162 is formed on the light-emitting layer 160. The upper electrode 162 may be formed as a transparent electrode or a reflective electrode, depending on the light emission type of the display device including the thin-film transistor substrate.

[0167] Therefore, an organic light-emitting diode 164 including the lower electrode 156, the light-emitting layer 160, and the upper electrode 162 can be formed.

[0168] An encapsulation layer 170 is formed on the organic light-emitting diode 164. The encapsulation layer 170 may have a stacked structure of inorganic and organic layers. For example, the organic layer may include a polymer curing material such as polyacrylate. For example, the polymer curing material may be formed through a cross-linking reaction of monomers. For example, the inorganic layer may include silicon oxide, silicon nitride, silicon carbide, aluminum oxide, tantalum oxide, hafnium oxide, zirconium oxide, titanium oxide, etc.

[0169] As described above, although the invention has been described with reference to exemplary embodiments, those skilled in the art will understand that various modifications and alterations can be made to the invention without departing from the spirit and scope of the invention.

[0170] Industrial availability

[0171] This invention can be applied to a variety of display devices that can be equipped with organic light-emitting display devices. For example, this invention can be applied to various display devices such as display devices for vehicles, ships and aircraft, portable communication devices, display devices for display or information transmission, medical display devices, and display devices for home appliances.

Claims

1. A display device comprising: a first thin film transistor of silicon type provided over a substrate; a first interlayer insulating film covering the first thin film transistor; an active pattern provided over the first interlayer insulating film and using indium-gallium-zinc oxide having a thickness of 150 A to 400 A; a gate insulating film covering the active pattern; a gate pattern disposed over the gate insulating film; and a second interlayer insulating film covering the gate pattern, wherein the active pattern has a refractive index of 1.92 to 1.93 at a wavelength of 632 nm.

2. The display device according to claim 1, wherein 3. The display device according to claim 1, wherein The hydrogen concentration in the gate insulating film is higher than 3.0E+20 atom / cm 3 and lower than 1.2E+21 atom / cm 3 .

4. The display device according to claim 1, wherein The density of the active pattern is higher than 6.3 g / cm 3 and lower than 6.6 g / cm 3 . the first interlayer insulating film includes a lower first interlayer insulating film containing silicon nitride and an upper first interlayer insulating film containing silicon oxide.

5. The display device according to claim 4, wherein the lower first interlayer insulating film has a thickness of 300 A to 3000 A and the upper first interlayer insulating film has a thickness of 50 A to 5000 A.

6. The display device according to claim 4, wherein 7. The display device according to claim 4, wherein The upper first interlayer insulating film has a NO2 spin density of less than 5E+16 spins / cm2 3 .

8. The display device according to claim 1, wherein The hydrogen concentration of the upper first interlayer insulating film is higher than 3.0E+20 atom / cm 3 and lower than 9.9E+20 atom / cm 3 . the second interlayer insulating film includes a lower second interlayer insulating film containing silicon oxide and an upper second interlayer insulating film containing silicon nitride.

9. The display device according to claim 8, wherein the lower second interlayer insulating film has a thickness of 500 A to 5000 A.

10. The display device according to claim 8, wherein the upper second interlayer insulating film has a thickness of 1000 A to 5000 A.

11. The display device according to claim 8, wherein 12. The display device according to claim 1, wherein The hydrogen concentration in the upper second interlayer insulating film is 1.19E+22 atom / cm 3 to 1.28E+22 atom / cm 3 .

13. A display device comprising: The spin density of NO2 in the gate insulating film is less than 1.6E+19 spins / cm 3 . a first active pattern including polycrystal silicon; a first gate insulating film covering the first active pattern; a first gate pattern provided over the first gate insulating film; a second gate insulating film covering the first gate pattern; a second gate pattern provided over the second gate insulating film; a first interlayer insulating film covering the second gate pattern; a second active pattern provided over the first interlayer insulating film and including an oxide semiconductor material; a third gate insulating film covering the second active pattern; a third gate pattern disposed over the third gate insulating film; and a second interlayer insulating film covering the third gate pattern and including a lower second interlayer insulating film containing silicon oxide and an upper second interlayer insulating film containing silicon nitride, wherein the second active pattern has a refractive index of 1.92 to 1.93 at a wavelength of 632 nm.

14. The display device according to claim 13, wherein the second active pattern includes indium-gallium-zinc oxide and has a thickness of 150 A to 400 A.

15. The display device according to claim 13, wherein 16. The display device according to claim 13, wherein ​ The hydrogen concentration in the third gate insulating film is higher than 3.0E+20 atom / cm 3 and lower than 1.2E+21 atom / cm 3 . ​ The first interlayer insulating film includes a lower first interlayer insulating film containing silicon nitride and an upper first interlayer insulating film containing silicon oxide.

17. The display device according to claim 16, wherein The hydrogen concentration of the upper first interlayer insulating film is higher than 3.0E+20 atom / cm 3 and lower than 9.9E+20 atom / cm 3 .

18. The display device according to claim 13, wherein The upper second interlayer insulating film has a thickness of 1000 A to 5000 A.

19. The display device according to claim 13, wherein The third gate pattern includes a titanium film pattern and a molybdenum film pattern.

Images