The invention discloses a fabrication method of a
gallium nitride laser cavity surface, which comprises the steps of epitaxially growing a
gallium nitride laser structure on a substrate, obtaining an epitaxial
wafer,
coating an
ohmic contact layer of the epitaxial
wafer with
photoresist, applying an photoetching plate for standard photoetching, evaporating
metal on the epitaxial
wafer, fabricating a
metal mask on an epitaxial layer,
etching to an n-type optical confinement layer of a
laser, corroding and
etching to form a side wall of the cavity surface, and removing the
metal mask on the surface of the epitaxial layer, wherein the
gallium nitride laser structure comprises an n-type
ohmic contact layer, an n-type confinement layer, an n-type
waveguide layer, a
quantum well, an electronic
barrier layer, a p-type
waveguide layer, a p-type confinement layer and a p-type
ohmic contact layer sequentially from one side of the substrate. According to the method, the cavity surface with the level and
smooth surface is obtained by an induction
plasma etching and alkaline solution
corrosion method, so that the damage to the cavity surface caused by an
ion bombardment effect after a dry
corrosion technology is eliminated, the damage of
plasma to the cavity surface is repaired, and the
emissivity of the cavity surface is improved.