Semiconductor light emitting device, light emitting apparatus and production method for semiconductor light emitting device

A light-emitting system, characterized by comprising:

• a blue-light-emitting device emitting blue light;
• a luminescent layer including a yellow/yellowish phosphor which absorbs blue light emitted by the blue-light-emitting device to emit a yellow/yellowish fluorescence;
• and
• a supporter for supporting the blue-light-emitting device and the luminescent layer,
• wherein the yellow/yellowish phosphor is a silicate phosphor containing, as a main component, at least one type of a compound expressed by the chemical formula:
• (Sr1−a1−b1−xBaa1Cab1Eux)2SiO4
• (where 0≦a1≦0.3, 0≦b1≦0.8 and 0<x<1).

A method for fabricating a light-emitting semiconductor device including:

• a blue-light-emitting device emitting light having a main emission peak in the wavelength range greater than 430 nm and less than or equal to 500 nm;
• and a luminescent layer including a yellow/yellowish phosphor which absorbs blue light emitted by the blue-light-emitting device to emit a fluorescence having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive,
• the method being characterized by comprising the steps of:
• a) covering at least a light-extracting surface of the blue-light-emitting device with a phosphor paste including the yellow/yellowish phosphor which has an absolute specific gravity in the range from 3.0 to 4.65, both inclusive, and emits light having a main emission peak in the wavelength range from 560 nm to 600 nm, both inclusive, at room temperature, and with a resin which has an absolute specific gravity in the range greater than or equal to 0.8 and less than or equal to the absolute value of the yellow/yellowish phosphor;
• and
• b) curing the phosphor paste, thereby forming the luminescent layer,
• wherein in the step a), a phosphor including, as a base material, a compound containing at least one element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, lanthanoid, Ti, Zr, Hf, V, Nb, Ta, Mo, W, Zn, B, Al, Ga, In, Si, Ge, Sn and P and at least one element selected from the group consisting of O, S, Se, F, Cl and Br is used as the yellow/yellowish phosphor.

A method for fabricating a light-emitting semiconductor device, comprising the steps of:

• a) covering a light-extracting surface of a blue-light-emitting device with a phosphor paste including a resin and phosphor particles;
• and
• b) curing the phosphor paste,
• wherein the steps a) and b) are performed a plurality of times.

A method for fabricating a light-emitting semiconductor device, comprising the steps of:

• a) covering a light-extracting surface of a blue-light-emitting device with a phosphor paste including a resin and phosphor particles and having a viscosity in the range from 1 Pa·S to 100 Pa·S, both inclusive;
• and
• b) curing the phosphor paste,
• wherein the steps a) and b) are performed a plurality of times.

A method for fabricating a light-emitting semiconductor device, characterized by comprising the steps of:

• a) covering at least a light-extracting surface of a blue-light-emitting device which emits light having a main emission peak in the wavelength range greater than 430 nm and less than or equal to 500 nm, with a first phosphor paste including a base material of a translucent resin and phosphor particles including a yellow/yellowish phosphor;
• b) covering the first phosphor paste with a second phosphor paste including at least a translucent resin and containing a yellow/yellowish phosphor at a concentration lower than that in the first phosphor paste, after the step a) has been performed;
• and
• c) curing the first and second phosphor pastes,
• wherein in the step a), as the yellow/yellowish phosphors, a silicate phosphor which is a yellow/yellowish phosphor absorbing light emitted by the blue-light-emitting device to emit light having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive, and which contains, as a main component, at least one type of a compound expressed by the chemical formula
• (Sr1−a1−b1−xBaa1Cab1Eux)2SiO4
• (where 0≦a1≦0.3, 0≦b1≦0.8 and 0<x<1)
• is used.

A method for fabricating a light-emitting semiconductor device, characterized by comprising the steps of:

• a) attaching phosphor particles including a yellow/yellowish phosphor to at least a light-extracting surface of a blue-light-emitting device which emits light having a main emission peak in the wavelength range greater than 430 nm and less than or equal to 500 nm;
• b) covering at least the light-extracting surface of the blue-light-emitting device with a translucent resin, after the step a) has been performed;
• and
• c) curing the resin,
• wherein in the step a), as the yellow/yellowish phosphor, a silicate phosphor which is a yellow/yellowish phosphor absorbing light emitted by the blue-light-emitting device to emit light having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive, and which contains, as a main component, at least one type of a compound expressed by the chemical formula
• (Sr1−a1−b1−xBaa1Cab1Eux)2SiO4
• (where 0≦a1≦0.3, 0≦b1≦0.8 and 0<x<1)
• is used.

A method for fabricating a light-emitting semiconductor device, characterized by comprising the steps of:

• a) covering at least a light-extracting surface of a blue-light-emitting device which emits light having a main emission peak in the wavelength range greater than 430 nm and less than or equal to 500 nm, with a phosphor paste including a translucent resin and phosphor particles, which includes a yellow/yellowish phosphor and to whose surfaces positively charged substances are attached;
• and
• b) curing the phosphor paste,
• wherein in the step a), as the yellow/yellowish phosphor, a silicate phosphor which is a yellow/yellowish phosphor absorbing light emitted by the blue-light-emitting device to emit light having a main emission peak in the wavelength range from 550 nm to 600 nm, both inclusive, and which contains, as a main component, at least one type of a compound expressed by the chemical formula
• (Sr1−a1−b1−xBaa1Cab1Eux)2SiO4
• (where 0≦a1≦0.3, 0≦b1≦0.8 and 0<x<1)
• is used.