Excimer laser annealing

Sameshima, T. Usui, S. Sekiya, M. 1986. XeCl excimer laser annealing used in the fabrication of poly-Si TFTs. IEEE Electron Device Lett. 7 276-278. 

The current authors have also investigated the effect of excimer laser annealing on various metallic thin films. Examples of gold and indium ultrathin films are shown... 

Sera K, Okumura F, Uchida H, Itoh S, Kaneko S, Hotta K (1989) High-performance TFT s fabricated by XeCl excimer laser annealing of hydrogenated amorphous-silicon film. IEEE Trans Electron Device 36 2868-2872... 

Compaction has also been observed as a result of neutron irradiation and extended exposure to iatense uv (excimer) laser light (131,132). The compaction tends to relax over months at room temperature and can be reversed quickly by annealing at sufficiently high temperatures (133). 

Finally, we tried to activate dopant atoms using pulsed laser irradiation, which is effective in lowering the process temperature. The light source was a 308-nm XeCl excimer laser, which is a standard source for crystallizing a-Si films used in the LTPS process.19 A test sample of 76 nm thickness, prepared from the copolymerized solution (l-wt% phosphorus, 30-min UV irradiation, 500 °C 2hr annealing), was irradiated using a XeCl laser at various intensities to activate the dopant atoms. Figure 5.19 shows the relationship between the... 

Fig. 1.8. EPR spectra of thiolactic acid modified Ti02 colloids illuminated with 308 nm excimer laser at 4.3 K and annealed at different temperatures indicated at the figure...

Laser annealing processes are much less well characterized than the thermal annealing processes discussed above. SIMS depth profiles have been used to study these processes (44). The use of excimer lasers for semiconductor processing was recently reported. SIMS depth profiles of B In SI after XeCl laser annealing showed a nearly flat B distribution to a Junction depth of about 0.9 pm with an Initial Implant peak of about 0.3 pm... 

The technique consists of firing a pulsed excimer laser at a stoichiometric pellet of the material to be deposited and under suitable conditions of laser energy density, oxygen partial pressure, substrate tenperature and deposition angle, high quality films are deposited. What is remarkable about the process is the stoichiometric deposition of films adhieved by this technique. The composition of the pellet is closely reproduced in the films. A schematic of the deposition system is shown in fig. 4. The deposition and annealing parameters are shewn in table 3. 

Loreti etal. [199] used excimer laser to anneal amorphous silicon seed layers deposited on a metallic Ti/Pd/Ag multilayer (Figure 4.29). 

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