Granted Patent B2

US 12,266,744 · App. 17/284,825 · Granted Apr 1, 2025

Inventors: Mei See Boon (Sungai Siput, MY); Hui Chiang Teoh (Jitra, MY); Tomin Liu (Kuching, MY); Hui Ying Pee (Penang, MY); Asliza Alias (Penang, MY); Lay Teng Tan (Penang, MY); Yuan Liang (Penang, MY); Alex Kheng Hooi Lim (Penang, MY); Wing Yew Wong (Penang, MY)

Assignee: OSRAM Opto Semiconductors GmbH

H01L33/54H01L33/505H01L33/62H01L2933/005

Abstract

Claims (33)

1. A method comprising:

providing light-emitting diode chips;

providing individual phosphor bodies having applied individual sacrificial layers at top sides of the individual phosphor bodies only;

placing the individual phosphor bodies having the individual sacrificial layers applied on the top sides onto the light-emitting diode chips so that each one of the light-emitting diode chips is provided with one of the individual phosphor bodies having one of the individual sacrificial layers applied on its top side and so that stacks comprising one of the light-emitting diode chips, one of the individual phosphor bodies and one of the individual sacrificial layers result;

molding an encapsulation body directly around the stacks by a film assisted molding so that the stacks are pressed into a molding film, wherein, in places, top faces of the individual sacrificial layers facing away from the individual phosphor bodies remain unsealed with the molding film, and wherein the individual sacrificial layers seal the top sides of the individual phosphor bodies from a material of the encapsulation body; and

removing the individual sacrificial layers so that the top sides of the individual phosphor bodies are free of the individual sacrificial layers,

wherein removing the individual sacrificial layers comprise removing the individual sacrificial layers by wet blasting with at least one liquid,

wherein the wet blasting is performed with deionized water at a temperature of between 60° C. and 95° C., inclusive,

wherein the individual sacrificial layers are applied to the individual phosphor bodies prior to placing the individual phosphor bodies onto the light-emitting diode chips,

wherein the individual sacrificial layers comprise a water-soluble polymer, and

wherein the individual phosphor bodies are ceramic bodies.

2. The method according to claim 1 ,

wherein, because of the unsealed top faces while molding, the encapsulation body partly extends onto the top faces of the individual sacrificial layers and onto the top sides of the individual phosphor bodies, and

wherein the top sides of the individual phosphor bodies are completely freed of the encapsulation body by removing the individual sacrificial layers.

3. The method according to claim 2 ,

wherein a thickness of the encapsulation body on the individual sacrificial layers, prior to removing the individual sacrificial layers, is between 0.5 μm and 15 μm inclusive,

wherein area proportions of the top faces of the individual sacrificial layers covered with the encapsulation body is between 1% and 25% inclusive.

4. The method according to claim 1 , wherein the individual sacrificial layers have anti-wetting properties with respect to the material of the encapsulation body.

5. The method according to claim 4 , wherein the individual sacrificial layers comprise a fluorinated polymer.

6. The method according to claim 1 , wherein a thickness of the individual sacrificial layers is between 0.2 μm and 10 μm inclusive.

7. The method according to claim 1 , wherein the light-emitting diode chips are attached to first lead frame parts and are electrically connected with second lead frame parts by bond wires, and wherein the bond wires are completely encapsulated in the encapsulation body.

8. The method according to claim 1 , wherein, immediately after molding, all of the light-emitting diode chips are mechanically coupled to one another by the encapsulation body, and wherein thicknesses of the light-emitting diode chips together with associated phosphor bodies show a deviation of between 3 μm and 20 μm inclusive.

9. The method according to claim 8 , wherein the individual sacrificial layers are removed prior to singulating the encapsulation body, and wherein semiconductor devices are formed by singulating.

10. A method comprising:

providing light-emitting diode chips;

providing individual phosphor bodies having applied individual sacrificial layers at top sides of the individual phosphor bodies only;

placing the individual phosphor bodies having the individual sacrificial layers applied on the top sides onto the light-emitting diode chips so that each one of the light-emitting diode chips is provided with one of the individual phosphor bodies having one of the individual sacrificial layers applied on its top side and so that stacks comprising one of the light-emitting diode chips, one of the individual phosphor bodies and one of the individual sacrificial layers result;

molding an encapsulation body directly around the stacks by a film assisted molding so that the stacks are pressed into a molding film, wherein, in places, top faces of the individual sacrificial layers facing away from the individual phosphor bodies remain unsealed with the molding film, and wherein the individual sacrificial layers seal the top sides of the individual phosphor bodies from a material of the encapsulation body; and

removing the individual sacrificial layers so that the top sides of the individual phosphor bodies are free of the individual sacrificial layers,

wherein the individual sacrificial layers are applied to the individual phosphor bodies prior to placing the individual phosphor bodies onto the light-emitting diode chips,

wherein the individual phosphor bodies are ceramic bodies,

wherein the individual sacrificial layers are made of water-soluble polymer, and

wherein the individual sacrificial layers are removed by wet blasting with a water jet.

Assignments (1)

Continuity (1)

References Cited (35)