Laser damage characteristics of indium-tin-oxide film and polyimide film irradiated by 1064nm high power lasers

摘要

The damage characteristics of the indium-tin-oxide (ITO) layer and the polyimide (PI) layer, which are two constituentcomponents of a LCD, induced by a high-peak-power laser and a high-average-power laser are investigated. The PIalignment layer is pinned on the ITO film to imitate the structure of the LCD as much as possible in our study. Under theirradiation of the high-peak-power laser, the damage process of the PI/ITO/SUB sample involves thermally inducedplastic deformation, followed by cooling when the irradiation fluence is near the LIDT, and rupture when the irradiationfluence is higher. High-average-power laser irradiation results in damaged morphologies of the bulge for thePI/ITO/SUB sample. The temperature distributions induced by the pulsed laser and the high-repetition-rate laser areinvestigated. The damage is attributed to the intrinsic heat absorption of the ITO films. Under the irritation of the highpeak-power laser, the temperature rises rapidly to a high degree at very short time because of the instant strongabsorption in ITO layer, and resulted in vaporization of ITO layer consequently. Subsequently, the vaporized ITO breaksthrough the surface PI and develops the visible damage. However, under the irritation of high-average-power laser, ITOlayer absorbs laser energy, resulting in a slow temperature rise and a small temperature gradient.