Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces
We have investigated femtosecond laser-induced ablation of gallium arsenide and silicon using time-of-flight mass spectroscopy. Below the ablation threshold we observe free flight desorption of atoms from the laser heated surface. The absence of collisions between particles leaving the solid allows...
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| Format: | Conference item |
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1998
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| _version_ | 1826300253688561664 |
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| author | Cavalleri, A Sokolowski-Tinten, K Bialkowski, J von der Linde, D |
| author_facet | Cavalleri, A Sokolowski-Tinten, K Bialkowski, J von der Linde, D |
| author_sort | Cavalleri, A |
| collection | OXFORD |
| description | We have investigated femtosecond laser-induced ablation of gallium arsenide and silicon using time-of-flight mass spectroscopy. Below the ablation threshold we observe free flight desorption of atoms from the laser heated surface. The absence of collisions between particles leaving the solid allows to obtain the maximum surface temperature during laser irradiation of Gallium Arsenide. We estimated maximum surface temperatures of the order of 3500 K at the ablation threshold, where we observed a step-like increase in the number of detected particles. In the case of Silicon the existence of molecules of up to 6 atoms does not allow to measure the surface temperature. With increasing fluence free flight desorption transforms into a collisional expansion process. The behaviour of Gallium particles can be quantitatively described through Knudsen-layer theory, indicating that Gallium particles expand as a non-ideal gas close to the ablation threshold (gamma=Cv/Cp<5/3). Above fluences of approximately 2.5 Fth gamma approaches 5/3 indicating an ideal gas behaviour for the expanding material. Dilution into the two phase regime of a superheated liquid characterises ablation close to threshold. |
| first_indexed | 2024-03-07T05:14:22Z |
| format | Conference item |
| id | oxford-uuid:dca90357-6fbf-481d-bf02-0a753b0d1082 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T05:14:22Z |
| publishDate | 1998 |
| record_format | dspace |
| spelling | oxford-uuid:dca90357-6fbf-481d-bf02-0a753b0d10822022-03-27T09:19:13ZTime of flight mass spectroscopy of femtosecond laser ablation of solid surfacesConference itemhttp://purl.org/coar/resource_type/c_5794uuid:dca90357-6fbf-481d-bf02-0a753b0d1082Symplectic Elements at Oxford1998Cavalleri, ASokolowski-Tinten, KBialkowski, Jvon der Linde, DWe have investigated femtosecond laser-induced ablation of gallium arsenide and silicon using time-of-flight mass spectroscopy. Below the ablation threshold we observe free flight desorption of atoms from the laser heated surface. The absence of collisions between particles leaving the solid allows to obtain the maximum surface temperature during laser irradiation of Gallium Arsenide. We estimated maximum surface temperatures of the order of 3500 K at the ablation threshold, where we observed a step-like increase in the number of detected particles. In the case of Silicon the existence of molecules of up to 6 atoms does not allow to measure the surface temperature. With increasing fluence free flight desorption transforms into a collisional expansion process. The behaviour of Gallium particles can be quantitatively described through Knudsen-layer theory, indicating that Gallium particles expand as a non-ideal gas close to the ablation threshold (gamma=Cv/Cp<5/3). Above fluences of approximately 2.5 Fth gamma approaches 5/3 indicating an ideal gas behaviour for the expanding material. Dilution into the two phase regime of a superheated liquid characterises ablation close to threshold. |
| spellingShingle | Cavalleri, A Sokolowski-Tinten, K Bialkowski, J von der Linde, D Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title | Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title_full | Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title_fullStr | Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title_full_unstemmed | Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title_short | Time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| title_sort | time of flight mass spectroscopy of femtosecond laser ablation of solid surfaces |
| work_keys_str_mv | AT cavalleria timeofflightmassspectroscopyoffemtosecondlaserablationofsolidsurfaces AT sokolowskitintenk timeofflightmassspectroscopyoffemtosecondlaserablationofsolidsurfaces AT bialkowskij timeofflightmassspectroscopyoffemtosecondlaserablationofsolidsurfaces AT vonderlinded timeofflightmassspectroscopyoffemtosecondlaserablationofsolidsurfaces |