Ultraviolet irradiation apparatus

Abstract

Provided is a compact ultraviolet irradiation apparatus which is capable of emitting ultraviolet radiation with high efficiency. This ultraviolet irradiation apparatus includes, in a vessel, a semiconductor multi-layered. film element and an electron beam irradiation source for irradiating the semiconductor multi-layered film element with an electron beam, the vessel being hermetically sealed to have a negative internal pressure and having an ultraviolet transmitting window. Furthermore, the semiconductor multi-layered film element includes an active layer having a single quantum well structure or a multi quantum well structure of InxAlyGa1-x-yN (0≦x<1, 0<y≦1, x+y≦1), and the active layer of the semiconductor multi-layered film element is irradiated with an electron beam from the electron beam irradiation source. This allows the semiconductor multi-layered film element to emit ultraviolet radiation out of the vessel through the ultraviolet transmitting window. Furthermore, Equation (1) below is satisfied, 4.18×V1.50≦t≦10.6×V1.54   Equation (1) where V (kV) is the acceleration voltage of the electron beam and t (nm) is the thickness of the active layer.

Dependencies are inferred from the claim text.