pulsedlaserdeposition(pld)(編輯修改稿)
2025-08-13 17:03 本頁面
【文章內(nèi)容簡介】 ification lattice Processes in PLD lattice If laser pulse is long (ns) or repetition rate is high, laser may continue interactions Processes in Pulsed Laser Deposition 1. Absorption of laser pulse in material Qab=(1R)IoeaL (metals, absorption depths ~ 10 nm, depends on l) 2. Relaxation of energy (~ 1 ps) (electronphonon interaction) 3. Heat transfer, Melting and Evaporation when electrons and lattice at thermal equilibrium (long pulses) use heat conduction equation: (or heat diffusion model) abp QTKtTC ??????? )(?Processes in Pulsed Laser Deposition 4. Plasma creation threshold intensity: goverened by Saha equation: 5. Absorption of light by plasma, ionization (inverse Bremsstrahlung) 6. Interaction of target and ablated species with plasma 7. Cooling between pulses (Resolidification between pulses) p u l s et h r e s h o l d tcmWsxI 22/14104 ???????? ???? kTmm mmQ n nn i o nieienienie e x pIncredibly NonEquilibrium!!! At peak of laser pulse, temperatures on target can reach 105 K ( 40 eV!) Electric Fields 105 V/cm, also high magic fields Plasma Temperatures 30005000 K Ablated Species with energies 1 –100 eV PLD with Ultrafast Pulses ( 1 picosecond) see Stuart et al., Phys. Rev. B, 53 1749 (1996) A new research area! If the pulse width electron latticerelaxation time, heat diffusion, melting significantly reduced! M
物理相關(guān)推薦
鄂ICP備17016276號-1