This is performed with one material, so the substrate and thin film are the same, often silicon on silicon. This is often used to grow films that are Purer than the substrate, and which can be doped independently of it.

This is performed with different materials and often used to grow films of materials for which crystals can't otherwise be obtained e.g. Silicon on Sapphire, or graphene on hexagonal boron nitride. This method allows for optoelectronic Structures and bandgap engineered devices.

In this process, a heteroepitaxial film grows vertically and laterally simultaneously. It is used in silicon-based manufacturing processes and is particularly important for compound semiconductors such as gallium arsenide. Heteroepitaxy is often used for metal-semiconductor growth; many metal-semiconductor structures are used 'for contact applications and epitaxial growth allows for increased electron movement through a junction. However, trying to grow a layer of crystals atop a substrate that is different to it can present problems; matching lattices are important to minimize defects and increase electron mobility, but the process can lead to unmatched lattices. This mismatch can cause strained or relaxed growth, thus triggering interfacial defects, and straying from what is considered 'normal' can lead to changes in the electronic, optic, thermal and mechanical properties of the film.

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