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Al2O3 and MgO composite (Al2O3/MgO) films were rapidly deposited at low temperatures using filtered cathode vacuum arc (FCVA) technology, aiming to achieve good barrier properties for flexible organic light emitting diodes (OLED) thin-film encapsulation (TFE). As the thickness of the MgO layer decreases, the degree of crystallinity decreases gradually. The 3:2 Al2O3:MgO layer alternation type has the best water vapor shielding performance, and the water vapor transmittance (WVTR) is 3.26 × 10−4 g·m−2·day−1 at 85 °C and 85% R.H, which is about 1/3 of that of a single layer of Al2O3 film. Under the action of ion deposition, too many layers will cause internal defects in the film, resulting in decreased shielding ability. The surface roughness of the composite film is very low, which is about 0.3–0.5 nm depending on its structure. In addition, the visible light transmittance of the composite film is lower than that of a single film and increases with the increase in the number of layers. [ABSTRACT FROM AUTHOR]

The present study reports room temperature ferromagnetism observed in Co implanted, Er implanted and (Co, Er) co-implanted ZnO films deposited by filtered cathode vacuum arc (FCVA) on sapphire substrates. The microstructures, surface morphologies, electrical and magnetic properties of pure and implanted ZnO films were investigated. X-ray diffraction results confirm that the implantation of Co and Er ions cause the substitution of Zn ions without the formation of secondary phases. The results of X-ray photoelectron spectroscopy indicate that the Er ions and Co ions are in trivalent and divalent states, respectively. After ions implantation, the electrical properties of the films are improved and the carrier concentration of Er implanted ZnO film is higher than that of Co implanted ZnO film. Substantial intrinsic ferromagnetism has been observed for all the implanted ZnO films. The saturation magnetization for the Er implanted ZnO film is higher than that of the Co implanted ZnO film and the magnetization is further enhanced by (Co, Er) co-implanting. The carrier mediated exchange mechanism can well describe the origin of ferromagnetism in the doped ZnO films. Our results can provide a reference for preparing high-quality diluted magnetic semiconductors (DMSs) by RE elements and TM elements co-doping in ZnO films. [Display omitted] • A filtered cathode vacuum arc (FCVA) deposition system was used to grow ZnO films on sapphire substrates. • The saturation magnetization for the Er implanted ZnO film is higher than that of Co implanted ZnO. • The magnetization is enhanced by Co-Er co-doping compared with Co doped and Er doped film. • The magnetization shows carrier concentration-dependent behavior. [ABSTRACT FROM AUTHOR]

To overcome the moisture sensitivity of flexible organic light-emitting diode devices (OLEDs), physical vapor deposition (PVD) technology can be used to prepare films with excellent density for thin film encapsulation (TFE). The internal stress in the film should be modulated to enhance the flexibility, which can prevent structural degradation. To address these issues, a filtered cathode vacuum arc (FCVA) equipped with a superlow duty ratio high-bias pulsed was used to prepare Al 2 O 3 films with low internal stress (−57.6 MPa), excellent visible light transmittance, high packaging density, and good bending resistance. After 1000 bending cycles, the water vapor transmission rate (WVTR) for a film is increased to 5.57 × 10−3 g/m2/day at 85 °C and 85% relative humidity (R.H.). In addition, the molecular dynamics (MD) is employed to investigate the mechanism of film internal stress release, as well as the shallow implantation of ions brought about by high-bias pulse. [ABSTRACT FROM AUTHOR]

Organic light-emitting diode devices (OLEDs) industry is developing rapidly, however, OLEDs are very sensitive to oxygen and water, determining how to achieve better barrier effect is one of the main challenges of flexible OLEDs technology. Based on the filtered cathode vacuum arc (FCVA) technology, a dense aluminum oxide (Al 2 O 3) film with a thickness of about 100 nm was grown at room temperature for OLEDs encapsulation. The composition, structure, surface roughness, refractive index, light transmittance and other physical properties of the film were analyzed. The water vapor transmission rates (WVTRs) of the films were tested at 85 °C and 85% relative humidity (R.H.). Photoluminescence spectrum (PL) test was carried out to study the luminescence ability of tris(8-hydroxyquinoline) aluminum (Alq 3) before and after the deposition of Al 2 O 3 film. The results show that the amorphous Al 2 O 3 film with dense structure prepared by FCVA has high visible light transmittance. The Al 2 O 3 film reduces the WVTRs of the polyethylene naphthalate (PEN) film by four orders of magnitude and maintains the light-emitting performance of the organic light-emitting layer. These results indicate that the FCVA technology is a feasible method for preparing barrier films of flexible OLEDs. • The FCVA is applied to the field of OLEDs encapsulation. • Rapidly deposited Al 2 O 3 (15 nm/min) by FCVA do not reduce PL intensity of Alq 3. • Al 2 O 3 film with 100 nm thickness reaches low WVTRs value of 9.897 × 10−4 g/m2/day. [ABSTRACT FROM AUTHOR]

• A filtered cathode vacuum arc (FCVA) system was used to grow MgO films on sapphire substrates. • The magnetic moment for the Er implanted MgO film is higher than that of Co implanted MgO. • The magnetization is enhanced by Co-Er co-doping compared with Co doped and Er doped MgO. • The origin of the magnetism can be described by the bound magnetic polaron (BMP) model. The present study reports a high ferromagnetism acquired by co-implanting Co and Er ions in MgO films prepared by filtered cathode vacuum arc on Al 2 O 3 substrates. The resulting MgO films were analyzed with respect to their structures, surface morphologies, and magnetic properties. Magnetic measurements show that substantial intrinsic ferromagnetism has been found for all the doped MgO. The ferromagnetism for the Er-doped MgO is larger than that of the Co-doped MgO and it is further strengthened by Er-Co co-doping. The X-ray photoelectron spectroscopy analysis substantiates that a large number of oxygen vacancies (V o) are generated after the doping of Er and Co ions. The origin of the magnetism can be described by the V o mediated bound magnetic polaron (BMP) model. The increased number of BMP with higher moments and the coupling interaction of Er and Co accounts for the strong ferromagnetism in the co-doped films. Our research provides a new idea for manufacturing high-quality diluted magnetic oxides by co-doping rare earth and transition metal ions in MgO samples. [ABSTRACT FROM AUTHOR]