Optoelectronic component and method for producing it
View Patent ↗An optoelectronic component having a basic housing or frame ( 12 ) and at least one semiconductor chip ( 20 ), specifically a radiation-emitting or -receiving semiconductor chip, in a cavity ( 18 ) of the basic housing. In order to increase the efficiency of the optoelectronic component ( 10 ), reflectors are provided in the cavity in the region around the semiconductor chip. These reflectors are formed by virtue of the fact that a filling compound ( 28 ) filled at least partly into the cavity ( 18 ) is provided, the material and the quantity of the filling compound ( 28 ) being chosen in such a way that the filling compound, on account of the adhesion force between the filling compound and the basic housing, assumes a form which widens essentially conically from bottom to top in the cavity, and the conical inner areas ( 30 ) of the filling compound serve as reflector.
1. A method for producing an optoelectronic component having a basic housing, which has a cavity, and a semiconductor chip, which is arranged in the cavity and emits and/or receives electromagnetic radiation, the cavity extending from a front side of the basic housing into the basic housing, wherein a reflective filling compound is arranged in the cavity between the semiconductor chip and side walls of the cavity, of which reflective filling compound at least one of its surfaces facing toward the front side of the basic housing is curved like a concave mirror and forms a reflector area for part of the radiation, the method comprising:
(a) forming the basic housing with the cavity,
(b) positioning the semiconductor chip in the cavity;
(c) filling-in a reflective filling compound into the cavity, the reflective filling compound comprising epoxy resin and TiO 2 particles embedded in the epoxy resin, a proportion of TiO 2 particles in the reflective filling compound being between about 10% and 50% by volume; and
(d) arranging material and quantity of the reflective filling compound in such a way that
(i) relative to a bottom area of the cavity, a filling height (h F ) thereof adjacent to the semiconductor chip is less than a distance between a laterally radiation-emitting and/or radiation-receiving region of the semiconductor chip and the bottom area, and
(ii) a surface thereof, as seen from the semiconductor chip, curves concavely in its course towards the side walls of the cavity on account of adhesion force between the material of the reflective filling compound and material of the side walls, and the surface is formed as a reflector for the radiation.
2. The method of claim 1 , in which, after the filling-in of the reflective filling compound, a radiation-transmissive encapsulation compound is filled into the cavity, which covers at least those surfaces of the semiconductor chip that are still uncovered after the previous steps.
3. The method of claim 1 , further comprising the step of arranging a chip carrier substrate between the semiconductor chip and the basic housing, the chip carrier substrate having a side edge and being configured so that a trench is formed between the side edge and a respective side wall of the cavity, the reflective filling compound being situated in the trench.
4. The method of claim 3 , wherein the basic housing has a carrier body which essentially comprises a metallic material.
5. The method of claim 3 , wherein the chip carrier substrate essentially comprises silicon.
6. The method of claim 1 , wherein the particles have a refractive index which is higher than a refractive index of the rest of the material of the reflective filling compound.
7. The method of claim 6 , wherein the refractive index of the material of the particles is higher than a refractive index of the epoxy resin.
8. The method of claim 6 , wherein a proportion by volume of the particles in the reflective filling compound is chosen so that a reflectivity of the reflective filling compound is increased.