3-dimensional structures of pores in low-k films observed by quantitative TEM tomograph and their impacts on penetration phenomena

3-dimensional structures of pores in porous low-k films have been quantitatively observed by transmission electron microscopy (TEM) tomographic technique for the first time. The 3-dimensional (3-D) reconstruction images clarified that the shape of pores are distorted and connectivity of the pores, such as open or close pores, depended on pore formation technique in the films, e.g. template or nano-clustering technique. Quantitative information of pores structure from 3-D reconstruction images were obtained using a 3-D structure analysis algorithm. The size of pores and connectivity influenced on metal penetration into the pores during atomic layer deposition (ALD) and chemical penetration which resulted in void formation in porous low-k films.