Ultraviolet light-emitting device, method for manufacturing ultraviolet light-emitting device and method for manufacturing ultraviolet light-emitting module

1. An ultraviolet light-emitting device comprising:

a base; a nitride semiconductor ultraviolet light-emitting element flip-chip mounted on the base; and a lens that seals the nitride semiconductor ultraviolet light-emitting element and focuses or diffuses light emitted from the nitride semiconductor ultraviolet light-emitting device,

wherein the lens is composed of an amorphous fluororesin in which a structural unit of a polymer or copolymer has a fluorine-containing aliphatic cyclic structure and a terminal functional group is a perfluoroalkyl group, and a density of the amorphous fluororesin is larger than 2.11 g/cm 3 .

2. The ultraviolet light-emitting device according to claim 1 , wherein the density of amorphous fluororesin constituting the lens is greater than 2.21 g/cm 3 .

3. The ultraviolet light-emitting device according to claim 1 , wherein a part of a surface of the lens may be a spherical surface or a convex curved surface.

4. The ultraviolet light-emitting device according to claim 1 , wherein the emission center wavelength of the nitride semiconductor ultraviolet light-emitting element is 200 nm or more and 365 nm or less.

5. A method for manufacturing an ultraviolet light-emitting device, the method comprising: a first step of sealing a nitride semiconductor ultraviolet light-emitting element flip-chip mounted on a base to form a lens for focusing or diffusing light emitted from the nitride semiconductor ultraviolet light-emitting element;

wherein the lens is formed of an amorphous fluororesin in which a structural unit of a polymer or copolymer has a fluorine-containing aliphatic cyclic structure and a terminal functional group is a perfluoroalkyl group; and,

in the first step or a subsequent step, the amorphous fluororesin constituting the lens is heated to a glass transition temperature or higher, a pressure of 35 MPa or higher is applied to the amorphous fluororesin, and the lens is cooled to a temperature lower than the glass-transition temperature by 30° C. or more while the pressure is applied, thereby densifying the amorphous fluororesin.

6. The method for manufacturing an ultraviolet light-emitting device according to claim 5 , the method further comprising:

simultaneously forming the lens for sealing each of a plurality of nitride semiconductor ultraviolet light-emitting elements flip-chip mounted on a base plate in which a plurality of bases are integrated in the first step; and

a second step of dividing the base plate so that one or more of the nitride semiconductor ultraviolet light-emitting element sealed by the lens are included after densifying the amorphous fluororesin constituting the lens.

7. A method for manufacturing an ultraviolet light-emitting module, the method comprising:

a third step of mounting one or more of ultraviolet light-emitting device having a nitride semiconductor ultraviolet light-emitting element flip-chip mounted on a base and sealed by a lens on a mounting member; and

a fourth step of densifying the amorphous fluororesin after the third step,

wherein the lens is formed of an amorphous fluororesin in which a structural unit of a polymer or copolymer has a fluorine-containing aliphatic cyclic structure and a terminal functional group is a perfluoroalkyl group; and

in the fourth step, the amorphous fluororesin constituting the lens is heated to a glass-transition temperature or higher, a pressure of 35 MPa or higher is applied to the amorphous fluororesin, and the lens is cooled to a temperature lower than the glass-transition temperature by 30° C. or more while the pressure is applied.