Abstract:  Periodical Si quantum dots(QDs)/SiC multilayers were obtained by using the laser induced crystallization technique and the structural and optical properties were studied.The cross­sectional TEM measurements were performed to characterize the microstructures of laser­crystallized Si QDs/SiC multilayers.The periodically layered structures are well kept and the formation of Si QDs in a­Si layers can be clearly identified.It is found that with increasing the laser fluence，both the crystallinity ratio and the average dot size were increased.The optical absorption coefficient is gradually increased and optical band gap decreased accordingly.The p­i­n structures based on laser crystallized Si QDs/SiC multilayers on the Indium Tin Oxide(ITO)transparent electrode coated glass substrates were fabricated to get all­Si QDs­based solar cells containing Si QDs/SiC multilayers.KrF pulsed excimer laser was used to crystallize a­Si layer to form Si QDs，which could avoid damaging the ITO layer and the glass substrates during the long time high­temperature annealing process.The cell area was about 0.8 cm2.The rectification characteristics was observed and the rectification ratio reached to 102 at the applied voltage V＝±2 V，which indicated that the p­i­n structures are well formed with the laser crystallization method.The photovoltaic properties of all­Si QDs­based solar cells containing Si QDs/SiC multilayers were studied.It is worth noting that the external quantum efficiency(EQE)of all­Si QDs­based solar cells were located the spectral range of 300～700 nm and were influenced by different laser fluence，which must be controlled in a proper range.It is found that 170 mJ·cm－2 is the most suitable laser fluence.The short circuit current density(Jsc)and the open circuit voltage(Voc)obtained in the 170 mJ·cm－2 laser crystallized­solar cell was 0.16 mA·cm－2 and 287 mV，respectively.These results laid a foundation for further research based on all­Si QDs­based solar cells.