Buffer layer

A buffer layer is a layer of a semiconductor grown on a substrate with a different lattice constant. With the growth of strained films , many misfit dislocations appear that spoil the crystal structure of the grown crystal. But with a sufficient thickness (usually more than a micrometer), the lattice constant of a grown crystal cut by a network of dislocations becomes close to the lattice constant of an unstressed material, on which structures of good quality can already be grown.