Laser lift-off (LLO) process using a diode pumped solid state (DPSS) laser with wavelength of 355 nm and pulse width of 37 ns was investigated experimentally and theoretically for non-contact delamination of the polyimide (PI) substrate from the glass carrier. Each pulse emitted from the DPSS laser was shaped into a top-hat square beam by an optical system including a diffractive optical element lens and a spatial filter. The typical FWHM size of the top-hat beam was $315\mu m\times 328\mu m$. The train of pulses was irradiated on the specimen in the form of a quasi-line beam through a scanner system for two representative pulse repetition rates (PRR) of 1 and 150 kHz. Experimental observations and theoretical simulations using the photothermal ablation model clarified that the intensive laser pulse induced extremely fast ablation inside the PI substrate, which caused the PI to delaminate internally along the PI/glass interface, leaving a residual PI layer of about 100 nm in thickness on the glass carrier. The successful non-overlap LLO by each pulse was confirmed optically by the Fizeau fringes at the threshold fluence of 240 $\mathit{mJ}/c{m}^2$. The overlapping irradiation of laser pulses, which minimized overlay or stitch errors, was able to lower the threshold fluence of each pulse by about 50% compared to the non-overlapping irradiation by a single pulse. With increasing PRR for the same number of irradiation overlaps, the threshold fluence was reduced considerably due to the thermal accumulation effect, but the thickness of the residual PI layer remaining on the glass carrier increased slightly.

实验和理论上研究了波长为355 nm，脉冲宽度为37 ns的二极管泵浦固态（DPSS）激光器的激光剥离（LLO）工艺，用于从玻璃载体中进行聚酰亚胺（PI）基板的非接触式分层。由DPSS激光器发射的每个脉冲通过包括衍射光学元件透镜和空间滤光器的光学系统被成形为礼帽方光束。高顶礼帽光束的典型FWHM尺寸为$315\mu 米\times 328\mu 米$。一系列的脉冲以准线束的形式通过扫描仪系统以1和150 kHz的两个代表性脉冲重复率（PRR）照射在样品上。使用光热烧蚀模型进行的实验观察和理论模拟表明，强激光脉冲在PI基板内部引起了极快的烧蚀，这导致PI沿PI /玻璃界面在内部分层，从而留下了厚度约为100 nm的残留PI层在玻璃载体上。Fizeau条纹在阈值通量为240时光学确认了每个脉冲是否成功完成了非重叠LLO$\mathit{兆焦耳}/C{米}^{\mathrm{2个}}$。与单个脉冲的非重叠照射相比，激光脉冲的重叠照射使重叠或缝合误差最小，能够将每个脉冲的阈值通量降低约50％。对于相同数量的照射重叠，随着PRR的增加，由于热累积效应，阈值通量大大降低，但是残留在玻璃载体上的残留PI层的厚度略有增加。