点击次数：

发表时间：2007-01-01

发表刊物：强激光与粒子束

期号：9

页面范围：1561-1566

ISSN号：1001-4322

摘要：In the early stage of UV excimer laser ablation of semiconductor, plasma induced by laser ablation was assumed at local thermodynamic equilibrium. One-dimension hydrodynamic model is presented for the laser ablation of Ge in a background gas (He) at 133.32 Pa and the characteristics of plasma induced by Gaussian-shaped KrF laser pulse with wavelength of 248 nm, pulse width of 17 ns, and peak power of 4 × 108 W/cm2. The results show that the ablated depth arrives 55 nm after laser pulse irradiation. The background gas He is gradually pushed away by the Ge vapor, forming a compression shock wave. And the maximum temperature always locates at the front of the shock wave. Spatial distribution of ionization degrees at different time shows that the first-order ionization degree of Ge always dominates in the region close to the target surface. The second-order ionization degree of Ge is a little bit bigger than the first-order ionization degree of Ge during the pulse in the center part of plume. But after the pulse, the second-order ionization degree of Ge drops gradually and then the first-order ionization degree of Ge dominates again.

备注：新增回溯数据