https://doi.org/10.1351/goldbook.14026
Imperfections connected with surface point defects (zero-dimensional), linear defects (one-dimensional), or square defects (two-dimensional) not including extrinsic chemical units in relation to the chemical formula of the solid.
Note: Surface vacancies, anionic vacancies (in n-type semiconductors), cationic vacancies (in p-type semiconductors), interstitial cations, edges, corners and kinks are some examples of intrinsic surface defects.