Light emitting device and method for producing the light emitting device

A light emitting device comprising:

• first LED elements emitting UV light;
• second LED elements emitting visible light;
• an SiC fluorescent screen which is doped with at least one of B and Al and with N and which emits visible light when it is excited by the light emitted from said first LED elements;
• and
• a substrate on which said first LED elements and said second LED elements are carried and which is made of an inorganic material;
• wherein said SiC fluorescent screen is arranged at a distancet from said first LED elements and said second LED elements, and
• wherein said SiC fluorescent screen has a periodic structure, on a surface at which the light emitted from the first LED elements is incident, which is formed by a period that is smaller than the emission wavelength of the first LED elements;
• and
• an AuSn type alloy layer which connects said first LED elements and said second LED elements and which has columnar crystals extending approximately perpendicular to said substrate.

A method for producing a light emitting device having:

• first LED elements for emitting UV radiation;
• second LED elements for emitting visible light;
• an SiC fluorescent screen that is doped with at least one of B and Al as well as N and emits visible light when excited by radiation emitted from the first LED elements;
• a substrate that carries the first LED elements and the second LED elements and is made of inorganic material;
• and
• an AuSn type alloy layer that binds the first LED elements and the second LED elements with the substrate and comprises columnar crystals extending substantially perpendicular to the substrate,
• comprising the steps of:
• forming an Sn film on a carrying surface of the substrate;
• forming an Au film on a mounting surface of the first LED elements and the second LED elements;
• contacting the Au film formed on the first LED elements and the second LED elements with the Sn film formed on the carrying surface of the substrate;
• and
• binding the first LED elements and the second LED elements to the substrate by heating the substrate in an atmosphere of forming gas containing a mixture of hydrogen gas and nitrogen gas with the Sn film and Au film in contact with each other.