Ion bombardment-induced transformation process on SiN_x surfaces to achieve vertical alignment of liquid crystal molecules

The vertical alignment (VA) of liquid crystal display (LCD) devices with upgraded performance is achieved on ion-bombarded SiN_x surfaces. We used a plasma-enhanced chemical vapour deposition method to deposit SiN_x thin films with high reliability. X-ray photoelectron spectroscopy revealed that change of orientation of LC molecules occurs on the SiO₂ surface, which is directionally transformed by ion-bombarded SiN_x thin film. The low-voltage transmittance characteristics and reduced response times indicate that the SiN_x-based VA-LCDs have potential for low-power operating and high-speed LCD applications.