發(fā)布時間：2018-01-08 11:08

  本文關(guān)鍵詞：飛秒激光打孔硅的孔洞形貌研究　出處：《光子學(xué)報》2017年10期 　論文類型：期刊論文

  更多相關(guān)文章： 飛秒激光 硅 非熱效應(yīng) 雙溫方程 等離子體 燒蝕輪廓

【摘要】：在飛秒激光打孔硅材料過程中,為了得到表面等離子體效應(yīng)和激光燒蝕形成的孔洞對后續(xù)激光能量在孔內(nèi)分布的影響,建立單脈沖等離子體閾值理論模型及設(shè)計連續(xù)飛秒激光燒蝕硅材料實驗.理論計算得到的損傷閾值為0.21J/cm2,符合實驗?zāi)Ｐ蜏y得的閾值0.20~0.25J/cm2.當載流子密度達到臨界值Ncr,等離子體的激發(fā)會導(dǎo)致表面反射率短時間內(nèi)急劇上升.入射激光通量從0.5J/cm2增大到3.0J/cm2,燒蝕深度逐漸增大并趨于約1.1μm,同時脈寬從150fs減小到50fs,燒蝕結(jié)構(gòu)類似于橢圓形燒蝕輪廓.后續(xù)激光脈沖輻照在已形成的孔洞上時,基于時域有限差分法,控制光束與孔壁的夾角從79℃到49℃,激光能量越接近孔底中心,越易引發(fā)該范圍內(nèi)的等離子體激發(fā);且在不同偏振態(tài)光束輻照下,孔底的能量分布不同會造成相應(yīng)特殊的燒蝕形貌.增大激光通量和減小脈沖寬度獲得理想的初始孔洞結(jié)構(gòu),可使后續(xù)脈沖能量集中孔底中心區(qū)域,打孔效果更好.
[Abstract]:In the process of femtosecond laser drilling silicon material, in order to obtain the surface plasma effect and the effect of the cavity formed by laser ablation on the distribution of the subsequent laser energy in the hole. The theoretical model of monopulse plasma threshold and the experiment of continuous femtosecond laser ablation of silicon materials are established. The theoretical damage threshold is 0.21J / cm2. The threshold measured by the experimental model is 0.20 ~ 0.25J / cm ~ 2.When the carrier density reaches the critical value Ncr. The plasma excitation will cause the surface reflectivity to rise sharply in a short time. The incident laser flux increases from 0.5 J / cm 2 to 3.0 J / cm 2, and the ablation depth increases gradually and tends to about 1.1 渭 m. At the same time, the pulse width is reduced from 150 fs to 50 fs, and the ablation structure is similar to that of the elliptical ablation contour. If the angle between the beam and the hole wall is controlled from 79 鈩，

本文編號：1396843