التفاصيل البيبلوغرافية
| العنوان: |
Investigations on the modification of PMMA by ultrafast laser radiation from the UV to the mid-IR spectral range. |
| المؤلفون: |
Pflug, T.1, Olbrich, M.1, Horn, A.1, Roesch, R.2,3, Schubert, U.S.2,3, Hoppe, H.2,3 |
| المصدر: |
Optics & Lasers in Engineering. Dec2018, Vol. 111, p130-134. 5p. |
| مصطلحات موضوعية: |
*LASER beams, *SOLAR cells, *SPECTRAL imaging, *ABSORPTION, *WAVELENGTHS, *OPTICS |
| مستخلص: |
Highlights • The polymer PMMA (Poly(methyl methacrylate)) has been irradiated by femtosecond single pulsed laser radiation in a wide spectral range from the UV to the mid- IR range (λ = 260 nm, 475 nm, 700 nm, 3.0 µm, 3.4 µm, and 3.8 µm). • The topology of the irradiated structures are comparable for all wavelengths, except at the resonant wavelength, where also below the threshold fluence a rise of the volume is detectable. • The time and spatially resolved reflectometry has demonstrated no dependence on the exciting wavelength up to delay times of about 120 ps. • Due to the very broad spectral bandwidth of the laser radiation at the resonant wavelength of λ = 3.4 µm, only 24% of the laser radiation is absorbed linearly by the PMMA. Abstract Laser-processing of organics is of increasing interest for organic electronics, e.g. the isolation process of solar cells in organic photo voltaic modules. The ablation of PMMA by single pulsed ultrafast laser radiation is investigated in the spectral range from UV (260 nm) to the mid-IR (3.8 µm) in order to determine dependencies of the ablation process on the wavelength, and the pulse energy. At ultrafast pulse durations τ H < 100 fs linear absorption (photo-excitation or resonant-infrared absorption) and non-linear absorption (multi-photon absorption or tunnel ionization) represent the main processes. The excited PMMA features similar dynamics of the absorption up to delay times of 120 ps for all investigated wavelengths, determining the electronic excitation after irradiation as the dominant process. [ABSTRACT FROM AUTHOR] |
| قاعدة البيانات: |
Academic Search Index |
