Step-by-Step Laser Crystallization of Amorphous Si:H/SiN_x:H Multilayer for Active Layer in Microcavities

We report the crystallization and photoluminescence (PL) properties of amorphous Si:H/SiN_x:H multilayer (ML) films treated by step-by-step laser annealing. The results of Raman measurements show that the nanocrystalline Si (nc-Si) grains are formed in the a-Si:H layers under the constrained growth mechanism. The blue shift of PL peak with grain size is observed and can be attributed to the quantum confinement effect. For comparison, we also report the crystallization and PL of a-Si:H/SiN_x:H ML samples by normal one-step treatment. This method of step-by-step laser treatment will be a candidate to make nc-Si quantum dots in amorphous Si:H/SiN_x:H ML as an active layer in microcavities.