A method is provided for incorporating zeolite crystals in patterned structures, the zeolite crystals having pores (channels) with an orientation which is defined by the topology of the zeolite crystal type and the geometry of the patterned structure, resulting in pores parallel with the length axis of the patterned structures. The patterned structures may be vias (vertical contacts) and trenches (horizontal lines) in a semiconductor substrate. These zeolite crystals can advantageously be used for dense and aligned nanocarbon growth or in other words growth of carbon nanostructures such as carbon nanotubes (CNT) within the pores of the zeolite structure. The growth of CNT is achieved within the porous structure of the zeolite crystals whereby the pores can be defined as confined spaces (channels) in nanometer dimensions acting as a micro-reactor for CNT growth. A method for growing carbon nanostructures within zeolite crystals is also provided, by adding, after creation of the zeolite crystals, a novel compound within the porous structure of the zeolite crystals whereby said novel compound is acting as a carbon source to create the carbon nanostructures. The improved growth method gives a significantly higher carbon density (yield) compared to state of the art techniques.