Explanation

It refers to the preferential chemical corrosion of defects in semiconductors. It is an important method for displaying defects in semiconductors, and combined with optical microscopy observation, it can quickly detect defects. The liquid is usually composed of strong oxidizing agents (such as concentrated nitric acid and hydrogen peroxide), turbidity agents (usually hydrofluoric acid), and water, and sometimes buffering agents (such as ammonium fluoride and acetic acid) are added. Due to the disordered arrangement of atoms near the defects in the semiconductor crystal, the lattice distortion and strain are large, the defects will be preferentially corrosion during chemical corrosion, forming corrosion pits with specific morphology. The morphology of corrosion pits is related to the defect type, crystal orientation and doping concentration of semiconductor chips. The corrosion pits of defects can usually be observed with an optical microscope.

Classification