Stoichiometric silicon nitride thin films for gas barrier, with applications to flexible and stretchable OLED encapsulation

Abstract

This study reveals that the stoichiometricity of silicon nitride thin films (SiNx-TFs) significantly governs the packing density and water vapor transmission rate (WVTR), and it can be controlled by chemical reactions accompanied by the removal of oxygen impurities with a nitrogen neutral beam (N-NB). Here, oxygen contents of SiNx-TFs are reduced through the formation of volatile NOx, and their amount is dominated by the energy of the N-NB reflected from a negatively biased reflector (0 to −60 V). The single-layered stoichiometric SiNx-TFs with a thickness of 100 nm provides the WVTR of 6.2 × 10−6 g/(m2day), with a density and composition ratio of N/Si stoichiometry at 3.13 g/cm3 and 1.33, respectively. This optimized SiNx-TF encapsulated top-emission organic light-emitting diode has reliability under harsh condition (85 °C and 85% relative humidity) for 830 h or more.

Solution‐Processed Gas Barriers with Glass‐Like Ultrahigh Barrier Performance

“…To interpret the trend of the WVTR values from the viewpoint of the densification process, Figure 4a shows the fitting results in the ellipsometry measurement for the PHPS and PDSN layers with different VUV doses. As the refractive indices of inorganic oxide [44,45] and silicon nitride layers [46][47][48][49] are proportional to their layer densities, the densification can be evaluated from the refractive index. The PHPS and PDSN layers were fitted using a single-layer model with a Gaussian oscillator and a four-layer model containing SiO 2 at the surface and three single-layer models, respectively, referring to previous work.…”

Hydrogen bonded polymer complex thin films for highly stretchable gas barriers

“…[1][2][3][4][5] While barrier tends to improve with increased stiffness, 6,7 highly stretchable gas barrier films are required for applications in next-generation stretchable electronics, such as deformable batteries and flexible OLEDs. 8,9 Gas barrier films are often constructed of polymeric materials due to their light weight, low cost, and easily processable nature. 10 Barrier properties of polymer films can be significantly improved via the incorporation of inorganic nanomaterials, even in low concentrations.…”

Enhancing the Stability of Perovskite Solar Cells with a Multilayer Thin-Film Barrier

“…However, the limitation of thin-film encapsulation for PSCs in some common deposition methods like sputtering, ALD, and so forth usually involves high energy input, high temperature, or humidity, which is beyond the tolerance of the perovskite film. While adopting the lower temperature or energy input technique, the barrier performance will be discounted . Thus, it is desirable to develop low-cost, low-damage, and robust thin-film encapsulation with high barrier property for PSCs.…”

“…While adopting the lower temperature or energy input technique, the barrier performance will be discounted. 18 Thus, it is desirable to develop lowcost, low-damage, and robust thin-film encapsulation with high barrier property for PSCs.…”