Apparatus for irradiating a substrate
Known apparatuses for irradiating a substrate include a receptacle for the substrate to be irradiated having a circular irradiation surface and a first optical emitter having at least one emitter tube arranged in an illumination plane extending parallel to the irradiation surface. The illumination length of the emitter tube includes a middle section and two end sections, the length of the middle section accounting for at least 50% of the illumination length. The receptacle and the optical emitter are movable relative to each other. An apparatus for thermal treatment of a substrate, enabling ho-mogeneous and/or rotationally symmetrical heating of the substrate and requiring less complexity in its design and control technology, includes a middle section of the emitter tube having a steadily decreasing curvature, provided that the illumination length of the emitter tube extends over an angle of curvature of less than 2π.
1. An apparatus for irradiating a substrate, the apparatus comprising a receptacle for the substrate to be irradiated, the substrate having a circular irradiation surface, a first optical emitter having at least one emitter tube arranged in an illumination plane extending parallel to the irradiation surface, the at least one emitter tube comprising an illumination length having a middle section and two end sections, wherein the length of the middle section accounts for at least 50% of the illumination length, wherein the receptacle and the optical emitter are movable with respect to each other, and wherein the middle section comprises a curvature that continually decreases from one of the two end sections to the other of the two end sections, provided that the illumination length of the emitter tube extends over an angle of curvature of less than 2π it rad.
2. The apparatus according to claim 1 , wherein the middle section comprises a curvature of an arithmetic spiral.
3. The apparatus according to claim 1 , wherein the circular irradiation surface comprises a center defining a pole of a planar polar coordinate system comprising coordinate lines in a form of concentric circles to define an angle φ and comprising ray axes to define a radius r of a coordinate in the polar coordinate system and provides the curvature of the middle section to be described by coordinates according to the following mathematical function:
r=k*φ and φ<2π rad,
wherein k is a constant factor.
4. The apparatus according to claim 3 , wherein the curvature of the emitter tube is given by a curve passing through centers of cross-sectional surfaces of the emitter tube, wherein the curve deviates at no position by more than 1 mm from the curvature given by the mathematical function.
5. The apparatus according to claim 4 , wherein the curve deviates at no position by more than 0.3 mm from the curvature given by the mathematical function.
6. The apparatus according to claim 1 , wherein the circular irradiation surface comprises a center defining a pole of a planar polar coordinate system comprising coordinate lines in a form of concentric circles to define an angle φ and comprising ray axes to define a radius r of a coordinate in the polar coordinate system, and wherein the middle section comprises a first part-length, in which the curvature of the emitter tube is described by coordinates according to the mathematical function:
r=k 1 *φ and φ<2π rad,
and comprises a second part-length, in which the curvature of the emitter tube is defined by coordinates according to the mathematical function:
r=k 2 *φ and φ<2π rad,
wherein k 1 and k 2 are constant factors and k 1 ≠k 2 .
7. The apparatus according to claim 1 , wherein the illumination length of the emitter tube extends over an angle of curvature of less than π rad.
8. The apparatus according to claim 1 , wherein the apparatus has just a single curved optical emitter.
9. The apparatus according to claim 1 , wherein the apparatus comprises at least one additional optical emitter having a curved emitter tube extending in an illumination plane parallel to the irradiation surface and having an illumination length comprising a middle section and two end sections, wherein the length of the middle section of the at least one additional optical emitter accounts for at least 50% of the illumination length.
10. The apparatus according to claim 9 , wherein the length of the middle section of the at least one additional optical emitter accounts for at least 90% of the illumination length.
11. The apparatus according to 9 , wherein the first optical emitter irradiates an inner irradiation surface, as seen in a radial direction, and the at least one additional optical emitter irradiates an outer irradiation surface, as seen in a radial direction, and wherein the inner and outer irradiation surfaces overlap at least partially.
12. The apparatus according to claim 9 , wherein the irradiation surface comprises a center and a ray axis originates in the center and extends radially outward and intersects the first and the at least one additional emitter.
13. The apparatus according to claim 9 , wherein the optical emitters, altogether, are arranged in the shape of a spiral.
14. The apparatus according to claim 1 , wherein the end sections also comprise a curvature of an arithmetic spiral.
15. The apparatus according to claim 1 , wherein the length of the middle section of the first optical emitter accounts for at least 90% of the illumination length.
16. A method for processing of semiconductor wafers, the method comprising irradiating the semiconductor wafers using an apparatus according to claim 1 , having an optical emitter in the form of an infrared emitter.
17. A method for the curing of coatings on optical storage media or semiconductor wafers, the method comprising irradiating the optical storage media or semiconductor wafers using an apparatus according to claim 1 , having an optical emitter in the form of a gas discharge emitter.