Process for HMDSO thermal stability

Abstract

Various embodiments of the present disclosure generally relate to methods for forming organic light emitting diode (OLED) devices. Forming the OLED device includes depositing a first barrier layer on a substrate having an OLED structure disposed thereon. A first sub-layer of a buffer layer is then deposited on the first barrier layer. The first sub-layer of the buffer layer is cured with a mixed gas plasma. Curing the first sub-layer includes generating water from the mixed gas plasma in a process chamber in which the curing occurs. The deposition of the first sub-layer and the curing of the first sub-layer are repeated one or more times to form a completed buffer layer. A second barrier layer is then deposited on the completed buffer layer.

Description

[0001] This application is a divisional application of an invention patent application with an application date of October 1, 2019, application number 201980088206.5, and invention name “Method for Thermal Stability of HMDSO”. background Technical Field

[0003] Various embodiments of the present disclosure are generally directed to methods for forming organic light emitting diode (OLED) devices, and more particularly to methods for encapsulating OLED structures. Background Art

[0004] OLEDs are used in the manufacture of television screens, computer monitors, mobile phones, other handheld devices, etc. for displaying information. Recently, OLED displays have gained considerable attention in display applications due to their advantages such as faster response time, greater viewing angle, higher contrast, lighter weight, lower power, and compliance to flexible substrates compared to liquid crystal displays (LCDs).

[0005] OLED structures may have a limited useful life, characterized by a decrease in electroluminescent efficiency and an increase in drive voltage. The main cause of OLED structure degradation is the formation of non-emissive dark spots due to moisture or oxygen ingress. For this reason, OLED structures are typically encapsulated by an organic layer sandwiched between inorganic layers. The organic layer is used to fill any voids or defects in the first inorganic layer so that the second inorganic layer has a substantially uniform surface or deposition.

[0006] Therefore, there is a need for improved methods and apparatus for encapsulating OLED structures. Summary of the invention

[0007] Various embodiments of the present disclosure are generally directed to methods for forming an OLED device. Forming the OLED device includes depositing a first barrier layer on a substrate having an OLED structure disposed thereon. A first sublayer of a buffer layer is then deposited on the first barrier layer. The first sublayer of the buffer layer is cured with a mixed gas plasma. Curing the first sublayer includes generating water from the mixed gas plasma in a process chamber where curing occurs. Deposition of the first sublayer and curing of the first sublayer are repeated one or more times to form a completed buffer layer. A second barrier layer is then deposited on the completed buffer layer.

[0008] In one embodiment, a method for forming an OLED device includes: depositing a first barrier layer on a region of a substrate having an OLED structure disposed thereon; depositing a first sublayer of a buffer layer on the first barrier layer; and curing the first sublayer with a mixed gas plasma. Curing the first sublayer includes: generating water from the mixed gas plasma in a chamber where curing occurs. The method further includes: repeating the deposition of the first sublayer and the curing of the first sublayer one or more times to form a completed buffer layer; and depositing a second barrier layer on the completed buffer layer.

[0009] In another embodiment, a method for forming an OLED device in a vacuum environment in a single process chamber includes: depositing a first barrier layer on an area of ​​a substrate on which an OLED structure is disposed; and depositing a first sublayer of a buffer layer on the first barrier layer. The thickness of the first sublayer is between about 0.05 μm and 0.2 μm. The method further includes: curing the first sublayer with a mixed gas plasma. Curing the first sublayer includes: generating water from the mixed gas plasma in a single process chamber where curing occurs. The method further includes: repeating the deposition of the first sublayer and the curing of the first sublayer one or more times to form a completed buffer layer. The thickness of the completed buffer layer is between about 0.5 μm and 1.5 μm. The method further includes: depositing a second barrier layer on the completed buffer layer.

[0010] In yet another embodiment, a method for forming an OLED device in a vacuum environment in a single process chamber includes: forming a contact layer over a substrate; forming an OLED structure over the contact layer; depositing a first barrier layer over the OLED structure; depositing a first sublayer of a buffer layer over the first barrier layer; and curing the first sublayer with a mixed gas plasma. Curing the first sublayer includes: generating water from the mixed gas plasma in the single process chamber where curing occurs. The method further includes: repeating the deposition of the first sublayer and the curing of the first sublayer one or more times to form a completed buffer layer; and depositing a second barrier layer over the completed buffer layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to understand the above-mentioned features of the present disclosure in a detailed manner, a more specific description of the present disclosure briefly summarized above can be achieved with reference to a plurality of embodiments, some of which are depicted in the accompanying drawings. However, it should be noted that the accompanying drawings depict only exemplary embodiments and therefore should not be considered as limiting the scope of the embodiments, and other equivalent embodiments may be allowed.

[0012] Figure 1 is a schematic cross-sectional view of a PECVD apparatus that may be used to perform the methods described herein, according to one embodiment.

[0013] Figure 2is a flow chart of a method for forming an OLED device according to one embodiment.

[0014] FIG. 3A to FIG. 3H Describes an embodiment of the Figure 2 Schematic cross-sectional views of an OLED device during various stages of the method.

[0015] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0016] Various embodiments of the present disclosure are generally directed to methods for forming an OLED device. Forming the OLED device includes depositing a first barrier layer on a substrate having an OLED structure disposed thereon. A first sublayer of a buffer layer is then deposited on the first barrier layer. The first sublayer of the buffer layer is cured with a mixed gas plasma. Curing the first sublayer includes generating water from the mixed gas plasma in a process chamber where curing occurs. Deposition of the first sublayer and curing of the first sublayer are repeated one or more times to form a completed buffer layer. A second barrier layer is then deposited on the completed buffer layer.

[0017] Figure 1 1 is a schematic cross-sectional view of a plasma enhanced chemical vapor deposition (PECVD) apparatus 101 that can be used to perform the operations described herein. The PECVD apparatus 101 includes a chamber 100 in which one or more films can be deposited onto a substrate 120. The chamber 100 generally includes a wall 102, a bottom 104, and a showerhead 106, which together define a process space. The process space can be a vacuum environment. A substrate support 118 is disposed within the process space. Access to the process space is via a slit valve opening 108 so that the substrate 120 can be transferred into and out of the chamber 100. The substrate support 118 can be coupled to an actuator 116 to raise and lower the substrate support 118. A lifting pin 122 is movably disposed via the substrate support 118 to move the substrate 120 to and from the substrate receiving surface. The substrate support 118 can also include a heating and / or cooling element 124 to maintain the substrate support 118 at a desired temperature. The substrate support 118 may also include an RF return strap 126 to provide an RF return path around the perimeter of the substrate support 118 .

[0018] The spray head 106 is coupled to the backing plate 112 via a fastening mechanism 150. The spray head 106 may be coupled to the backing plate 112 via one or more fastening mechanisms 150 to help prevent the spray head 106 from sagging and / or to control the straightness / curvature of the spray head 106.

[0019] A gas source 132 is coupled to the backing plate 112 to provide gas to a processing region between the showerhead 106 and the substrate 120 via a gas channel in the showerhead 106. A vacuum pump 110 is coupled to the chamber 100 to maintain the process space at a desired pressure. An RF source 128 is coupled to the backing plate 112 and / or the showerhead 106 via a matching network 190 to provide an RF current to the showerhead 106. The RF current creates an electric field between the showerhead 106 and the substrate support 118 so that a plasma can be generated from the gas between the showerhead 106 and the substrate support 118.

[0020] A remote plasma source 130, such as an inductively coupled remote plasma source 130, may also be coupled between the gas source 132 and the backing plate 112. Between processing substrates, a cleaning gas may be provided to the remote plasma source 130 to generate a remote plasma. Radicals from the remote plasma may be provided to the chamber 100 to clean the chamber 100 components. The cleaning gas may be further excited by a radio frequency source 128 provided to the showerhead 106.

[0021] The showerhead 106 can be further coupled to the backing plate 112 via a showerhead suspension 134. In one embodiment, the showerhead suspension 134 is a flexible metal skirt. The showerhead suspension 134 can have a lip 136 on which the showerhead 106 can rest. The backing plate 112 can rest on an upper surface of the ledge 114 coupled to the chamber wall 102 to seal the chamber 100 to form a vacuum environment.

[0022] Figure 2 is a flow chart of a method 200 for forming an OLED device according to one embodiment. Figures 3A to 3G Depicted in Figure 2 Schematic cross-sectional view of an OLED device 350 during different stages of method 200 . FIG. 3B to FIG. 3F Depiction Figure 3A The method 200 can be used with Figure 1 The method 200 begins at operation 202 by providing a substrate 300 on which a preformed OLED structure 304 is disposed. The substrate 300 may be Figure 1 The substrate 120. Figure 3A As shown in FIG. 1 , a substrate 300 may be provided with a contact layer 302 on the substrate 300 , and an OLED structure 304 may be provided on the contact layer 302 .

[0023] At operation 204, if Figure 3A As shown in FIG. 3 , a mask 310 is aligned over substrate 300 so that OLED structure 304 is exposed through openings 312 that are not protected by mask 310. Mask 310 is positioned so that a portion 306 of contact layer 302 adjacent to OLED structure 304 is covered by mask 310 so that any subsequently deposited material is not deposited on portion 306. Portion 306 of contact layer 302 is an electrical contact for OLED device 350, so no material should be deposited on portion 306. Mask 310 may be made of a metallic material, such as

[0024] At operation 206, if Figure 3A As shown in , a first barrier layer 308 is deposited on a substrate 300. The first barrier layer 308 has a first portion 308a and a second portion 308b. The first portion 308a of the first barrier layer 308 is deposited via an opening 312 onto an area of ​​the substrate 300 exposed by the mask 310, the area of ​​the substrate 300 exposed by the mask 310 including a portion of the OLED structure 304 and the contact layer 302. The second portion 308b of the first barrier layer 308 is deposited on the mask 310 covering a second area of ​​the substrate 300, the second area of ​​the substrate 300 including a portion 306 of the contact layer 302. The first barrier layer 308 is a dielectric layer, such as silicon nitride (SiN), silicon oxynitride (SiON), silicon dioxide (SiO2), aluminum oxide (Al2O3), aluminum nitride (AlN), or other suitable dielectric layers. The first barrier layer 308 may be deposited by a suitable deposition technique, such as chemical vapor deposition (CVD), PECVD, physical vapor deposition (PVD), spin coating, or other suitable techniques.

[0025] At operation 208, if Figure 3B As shown in FIG. 3 , after the first barrier layer 308 is deposited on the substrate 300, the first sublayer 320 of the partial buffer layer 316 is deposited on the first barrier layer 308. The thickness 322 of the first sublayer 320 of the partial buffer layer 316 may be about 0.05 μm to 0.2 μm. The first sublayer 320 of the partial buffer layer 316 may be deposited on the substrate 300 on the area of ​​the substrate 300 exposed by the mask 310 through the opening 312 of the mask 310, covering the first portion 308a of the first barrier layer 308. Although not shown in FIG. Figure 3B However, as shown in the enlarged section depicted in FIG. 3 , a portion of the first sublayer 320 of the buffer layer 316 is deposited over the second portion 308 b of the first barrier layer 308 .

[0026] The partial buffer layer 316 may be fluorinated plasma polymerized hexamethyldisiloxane (pp-HMDSO:F) deposited in a PECVD chamber such as Figure 1 The chamber 100 is provided. The deposition of the pp-HMDSO:F layer is achieved by flowing one or more fluorine-containing gases and HMDSO gas together with O2 or N2O gas. The fluorine-containing gas can be nitrogen fluoride (NF3), silicon fluoride (SiF4), fluorine gas (F2), carbon tetrafluoride (CF4) or any combination of nitrogen fluoride (NF3), silicon fluoride (SiF4), fluorine gas (F2), carbon tetrafluoride (CF4). The fluorine-doped plasma polymerized HMDSO layer has excellent particle coverage performance and surface flattening effect. The resulting first sublayer 320 has a fluorine content of less than 10 atomic percent.

[0027] During the deposition of pp-HMDSO:F, the ratio of the flow of the fluorine-containing gas to the HMDSO gas can be between about 0.25 and about 1.5. If there is too much fluorine, the carbon in the HMDSO may be removed. In one embodiment, the PECVD of pp-HMDSO:F is performed under the following conditions. The flow rate of SiF4 is 125 standard cubic centimeters per minute (sccm) and the flow rate of HMDSO is 300 sccm. In other words, the ratio of SiF4 to HMDSO is between about 0.40 and about 0.45. The plasma is generated at 700 W and the chamber pressure is about 1800 mTorr. The pp-HMDSO:F is deposited at about 80 degrees Celsius and the distance between the substrate 300 and the showerhead 106 is between about 500 mil and 1200 mil.

[0028] The buffer layer 316 including pp-HMDSO:F may have properties including stress relief, particle conformality, and flexibility. These properties of the pp-HMDSO:F buffer layer 316 enable the buffer layer 316 including pp-HMDSO:F to eliminate the mutual influence between defects in the first barrier layer 308, and to level surface irregularities to form a smooth surface. However, due to the formation process of the pp-HMDSO:F buffer layer, the pp-HMDSO:F buffer layer may be physically soft, which will cause integration issues when stacked with the barrier layer. When the barrier layer is stacked on top of the soft pp-HMDSO:F buffer layer, a wrinkled surface is formed, and the soft pp-HMDSO:F layer loses the optical transmittance of the pp-HMDSO:F layer, making the device unsuitable as a top-emitting OLED device.

[0029] In order to harden the portion of the buffer layer 316 and prevent the formation of a wrinkled surface, plasma curing of the portion of the buffer layer 316 is used. At operation 210, as shown in FIG. Figure 3C As shown in , the first sub-layer 320 of the partial buffer layer 316 is cured to form a first hardened sub-layer 324 of the partial buffer layer 316 .

[0030] The curing of the portion of the buffer layer 316 is performed in a vacuum environment. In one embodiment, the curing is performed in the same process chamber as the deposition of the first sublayer 320 of the buffer layer (i.e., an in-situ curing process). Curing is performed using a mixed gas plasma or a plasma generated by a gaseous mixture, and the mixed gas plasma or the plasma generated by the gaseous mixture is configured to produce water (H2O) in the chamber where the curing occurs. The mixed gas plasma is configured to produce water for condensation curing, which introduces moisture into the chamber. The mixed gas plasma may include two or more gases selected from the following groups: ammonia (NH3), nitrous oxide (N2O), hydrogen (H2) and oxygen (O2). For example, the mixed gas plasma may include NH3 and N2O, H2 and N2O, H2 and O2, or NH3 and O2. In one embodiment, the mixed gas plasma may further include fluorine, such as nitrogen fluoride (NF3), silicon fluoride (SiF4), fluorine (F2) and / or carbon tetrafluoride (CF4).

[0031] The ratio of the mixed gas in the mixed gas plasma depends on the spacing between the substrate 300 and the showerhead of the processing chamber, such as Figure 1 of the showerhead 106. For example, if the spacing between the substrate 300 and the showerhead 106 is about 650 mil, then a 1:1 NH3 to N2O ratio may be used for a curing duration of about 10 to 15 seconds. In another example, if the spacing between the substrate 300 and the showerhead 106 is about 1000 mil, then a 3:1 NH3 to N2O ratio may be used for a curing duration of about 30 seconds. Therefore, the curing duration depends on the ratio of the mixed gases in the mixed gas plasma and the spacing between the substrate 300 and the showerhead 106. As such, the curing duration may be increased to compensate for a higher ratio between the mixed gases of the mixed gas plasma and to compensate for a larger spacing between the substrate 300 and the showerhead 106. As one or more sublayers of the buffer layer and the barrier layer are subsequently deposited on the first hardened sublayer 324, the first hardened sublayer 324 maintains the flexibility and optical transmittance of the first hardened sublayer 324.

[0032] In operation 212, operations 208 and 210 are repeated one or more times to deposit one or more additional sub-layers of the portion of the buffer layer 316 on the first solidified sub-layer 324, and each deposited sub-layer is individually solidified before depositing additional sub-layers. Figure 3D As shown in FIG. 1 , the second sublayer 326 of the partial buffer layer 316 is deposited on the first solidified sublayer 324, covering the first solidified sublayer 324. The thickness 330 of the second sublayer 326 of the partial buffer layer 316 may be about 0.05 μm to 0.2 μm. The first thickness 322 of the first sublayer 320 and the second thickness 330 of the second sublayer 326 may be the same thickness, or the first thickness 322 and the second thickness 330 may be different. Although not shown in FIG. Figure 3D However, as shown in the enlarged section depicted in FIG. 3 , a portion of the second sublayer 326 of the buffer layer 316 is deposited over the second portion 308 b of the first barrier layer 308 disposed on the mask 310 .

[0033] like Figure 3E As shown in , the second sublayer 326 of the partial buffer layer 316 is then cured to form a second cured sublayer 328 of the partial buffer layer 316. One or more additional sublayers 336 of the partial buffer layer 316 may then be separately deposited and cured, one sublayer at a time, to form a completed buffer layer 332, as shown in FIG. Figure 3F . Each time an additional sub-layer 336 is deposited, the additional sub-layer 336 is cured, and then another additional sub-layer 336 is deposited. Unless otherwise stated, the additional sub-layer 336 is deposited only on the cured sub-layer. As one or more additional sub-layers are subsequently deposited on each additional sub-layer 336, the flexibility and optical transmittance of each additional sub-layer 336 are maintained.

[0034] The thickness 334 of the finished buffer layer 332 may be about 0.5 μm to 1.5 μm. In one embodiment, one to fifteen additional sublayers 336 may be deposited on the first solidified sublayer 324 to form the finished buffer layer 332. In another embodiment, the finished buffer layer 332 includes ten sublayers, each of which is about 0.1 μm thick. As a barrier layer is subsequently deposited on the finished buffer layer 332, the finished buffer layer 332 maintains the flexibility and optical transmittance of the finished buffer layer 332.

[0035] Figure 3G A zoomed-out view of a completed buffer layer 332 deposited on an OLED device 350 is depicted. Figure 3GAs shown in FIG. 3 , the finished buffer layer 332 includes a first portion 332a and a second portion 332b . The first portion 332a of the finished buffer layer 332 is deposited on the first portion 308a of the first barrier layer 308 and the second portion 332b of the finished buffer layer 332 is deposited on the second portion 308b of the first barrier layer 308 .

[0036] At operation 214, Figure 3H As shown in FIG. 3 , a second barrier layer 314 is deposited on the substrate 300, covering the completed buffer layer 332 and the first barrier layer 308 formed on the OLED structure 304. The second barrier layer 314 includes a first portion 314a deposited on the first portion 332a of the completed buffer layer 332 and a second portion 314b deposited on the second portion 332b of the completed buffer layer 332.

[0037] The second barrier layer 314 may be a dielectric layer similar to the first barrier layer 308. The second barrier layer 314 is a dielectric layer such as SiN, SiON, SiO2 or other suitable dielectric layers. The second barrier layer 314 may be deposited by a suitable deposition technique such as CVD, PVD, spin coating or other suitable techniques.

[0038] Deposition of the barrier layer, deposition of the sub-layers of the buffer layer, and curing of the sub-layers of the buffer layer as described herein can be performed in the vacuum environment of a single deposition chamber, such as PECVD chamber 100. Performing the deposition and curing operations in the vacuum environment of a single deposition chamber allows for the formation of an OLED device without ever having to break the vacuum, eliminates or reduces delamination of the various layers, and further eliminates or reduces the risk of contaminants being introduced into the process chamber.

[0039] The process chamber can be purged between cycles to further minimize the risk of contamination. In one embodiment, a first barrier layer is deposited. The chamber is then purged so that there is no gas used to deposit the first barrier layer in the chamber used for subsequent processes. Afterwards, each of the multiple sublayers of the buffer layer is deposited and the sublayer is cured individually. The chamber is then purged again so that there is no gas used for the deposition and curing of the multiple sublayers of the buffer layer in the chamber used for subsequent processes. In one embodiment, each time a sublayer of the buffer layer is deposited, the chamber can be purged before curing the sublayer. In such an embodiment, the sublayer is then cured, and the chamber can be purged again before depositing additional sublayers of the buffer layer. Therefore, each time a sublayer is deposited, the chamber can be purged, and each time a sublayer is cured, the chamber can be purged again. Finally, the second barrier layer is deposited. The single chamber process can be beneficial to reduce the number of cycles and reduce the number of chambers (and equipment costs) using a multi-chamber process.

[0040] In summary, an OLED device is formed with a buffer layer comprising a plurality of sublayers sandwiched between two barrier layers. Each of these sublayers of the buffer layer is deposited and cured individually, followed by deposition of additional sublayers, thereby reducing or eliminating delamination of the various layers of the OLED device. In addition, these sublayers of the buffer layer are deposited and cured in the vacuum environment of a single process chamber. Performing deposition and curing operations in the vacuum environment of a single deposition chamber allows the OLED device to be formed without ever having to break the vacuum, further eliminating or reducing delamination of the various layers. In addition, the risk of contaminants being introduced into the process chamber is eliminated or reduced, so that the finished buffer layer can maintain the flexibility and optical transmittance of the finished buffer layer. In addition, performing deposition and curing operations in the vacuum environment of a single deposition chamber simplifies the method of forming an OLED device, can increase production and reduce associated costs.

[0041] While the foregoing is directed to several embodiments of the present disclosure, other and further embodiments of the present disclosure may be envisaged without departing from the basic scope thereof and the scope of the present disclosure is determined by the claims which follow.

Claims

1. An organic light emitting diode (OLED) device, comprising: OLED structure; a first barrier layer disposed around the OLED structure; and A buffer layer is disposed on the first barrier layer, the buffer layer comprising a plurality of sublayers, wherein the plurality of sublayers are individually solidified by mixed gas plasma, the mixed gas plasma comprising at least one pair selected from the group consisting of (a) NH3 and N2O, (b) H2 and N2O, (c) H2 and O2, (d) NH3 and O2, or (e) H2O.

2. The OLED device of claim 1, wherein the buffer layer comprises fluorinated plasma polymerized hexamethyldisiloxane (pp-HMDSO:F).

3. The OLED device of claim 1, wherein the plurality of sub-layers is between 2 sub-layers and 16 sub-layers, wherein each of the plurality of sub-layers is cured for about 10 seconds to about 30 seconds.

4. The OLED device of claim 1, further comprising a second barrier layer disposed on the buffer layer, wherein at least one of the first barrier layer and the second barrier layer comprises SiN, SiON, SiO2, Al2O3, or AlN. 5 . The OLED device of claim 1 , wherein each of the plurality of sub-layers has a thickness between about 0.05 μm and about 0.2 μm.

6. The OLED device of claim 1 , wherein water is generated from the mixed gas plasma when each of the plurality of sublayers is cured, and wherein the mixed gas plasma comprises at least one pair selected from the group consisting of (a) NH 3 and N 2 O, (b) H 2 and N 2 O, (c) H 2 and O 2, or (d) NH 3 and O 2.

7. The OLED device of claim 1, wherein the buffer layer has a thickness between about 0.5 μm and about 1.5 μm. 8 . The OLED device of claim 1 , wherein the buffer layer is disposed on the first barrier layer.

9. An organic light emitting diode (OLED) device comprising: OLED structure; a first barrier layer disposed around the OLED structure; a buffer layer disposed on the first barrier layer, the buffer layer comprising a plurality of sublayers, the plurality of sublayers being individually cured by mixed gas plasma, wherein water is generated from the mixed gas plasma when each of the plurality of sublayers is cured, and wherein a thickness of each of the plurality of sublayers is between about 0.05 μm and about 0.2 μm; and A second barrier layer is disposed on the buffer layer.

10. The OLED device of claim 9, wherein the buffer layer has a thickness between about 0.5 μm and about 1.5 μm.

11. The OLED device of claim 9, wherein the buffer layer comprises fluorinated plasma polymerized hexamethyldisiloxane (pp-HMDSO:F).

12. The OLED device of claim 9, wherein the mixed gas plasma comprises NH3 and N2O, H2 and N2O, H2 and O2, NH3 and O2, or H2O.

13. The OLED device of claim 9, wherein the plurality of sub-layers is between 2 sub-layers and 16 sub-layers.

14. The OLED device of claim 9, wherein at least one of the first barrier layer and the second barrier layer comprises SiN, SiON, SiO2, Al2O3, or AlN.

15. The OLED device of claim 9, wherein each of the plurality of sub-layers is cured for about 10 seconds to about 30 seconds.

16. The OLED device of claim 9, wherein the buffer layer is disposed on the first barrier layer.

17. An organic light emitting diode (OLED) device comprising: a contact layer disposed on the substrate; an OLED structure disposed on the contact layer; a first barrier layer disposed on the OLED structure; a buffer layer disposed on the first barrier layer, the buffer layer comprising a plurality of sub-layers that are individually cured by mixed gas plasma, wherein water is generated from the mixed gas plasma when each of the plurality of sub-layers is cured, and wherein the buffer layer has a thickness between about 0.5 μm and about 1.5 μm; and A second barrier layer is disposed on the buffer layer.

18. The OLED device of claim 17, wherein each of the plurality of sub-layers has a thickness between about 0.05 μm and about 0.2 μm.

19. The OLED device of claim 17, wherein the buffer layer comprises fluorinated plasma polymerized hexamethyldisiloxane (pp-HMDSO:F).

20. The OLED device of claim 17, wherein the mixed gas plasma comprises NH3 and N2O, H2 and N2O, H2 and O2, NH3 and O2, or H2O.

21. The OLED device of claim 17, wherein the plurality of sub-layers is between 2 sub-layers and 16 sub-layers, and wherein each sub-layer of the plurality of sub-layers is cured for about 10 seconds to about 30 seconds.

22. The OLED device of claim 17, wherein at least one of the first barrier layer and the second barrier layer comprises SiN, SiON, SiO2, Al2O3, or AlN.

23. The OLED device of claim 17, wherein the buffer layer is disposed on the first barrier layer.

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