Heating system comprising semiconductor light sources
The invention describes a heating system ( 100 ) and a corresponding method of heating a heating surface ( 180 ) of an object ( 150, 950 ) to a processing temperature of at least 100° C., wherein the heating system ( 100 ) comprises semiconductor light sources ( 115 ), and wherein the heating system ( 100 ) is adapted to heat an area element of the heating surface ( 180 ) with at least 50 semiconductor light sources ( 115 ) at the same time. The heating system ( 100 ) may be part of a reactor for processing semiconductor structures. The light emitted by means of the semiconductor light sources ( 115 ) overlaps at the heating surface ( 180 ). Differences of the characteristic of one single semiconductor light source ( 115 ) may be blurred at the heating surface ( 180 ) such that a homogeneous temperature distribution across a processing surface of a, for example, wafer may be enabled.
1. A method of heating a heating surface of an object to a processing temperature of at least 100° C., the method comprising:
providing a heating surface of an object;
providing semiconductor light sources wherein the semiconductor light sources are Vertical Cavity Surface Emitting Lasers;
arranging the semiconductor light sources in sub modules;
providing an electrical driver;
adapting the electrical driver to drive all semiconductor light sources of one sub module simultaneously;
adapting the heating system to heat the heating surface such that a first local temperature of a first part of a processing surface of a wafer deviates less than 0.5% from a second local temperature of a second part of the processing surface of the wafer being different from the first part of the processing surface by arranging at least one of the sub modules and the electrical driver;
heating an area element of the heating surface with at least 50 semiconductor light sources at the same time such that the processing surface of the wafer is homogeneously heated to a defined temperature.
2. A heating system for heating a heating surface of an object, comprising:
a plurality of semiconductor light sources, wherein an area element of the heating surface is heated with at least 50 semiconductor light sources simultaneously, the semiconductor light sources being Vertical Cavity Surface Emitting Lasers, wherein the heating surface is heated such that a first local temperature of a first part of a processing surface of a wafer deviates less than 0.5% from a second local temperature of a second part of the processing surface of the wafer, the second part being different from the first part, the semiconductor light sources being arranged in sub modules; and
an electrical driver configured to drive the semiconductor light sources of each sub module simultaneously, wherein the sub modules and the electrical driver are arranged such that the processing surface of the wafer is homogeneously heated to a predefined temperature, a processing temperature being at least 100° C.
3. A reactor for wafer processing, comprising:
a heating system for heating a heating surface of an object that includes:
a plurality of semiconductor light sources, wherein an area element of the heating surface is heated with at least 50 semiconductor light sources simultaneously, the semiconductor light sources being Vertical Cavity Surface Emitting Lasers, wherein the heating surface is heated such that a first local temperature of a first part of a processing surface of a wafer deviates less than 0.5% from a second local temperature of a second part of the processing surface of the wafer, the second part being different from the first part, the semiconductor light sources being arranged in sub modules;
an electrical driver configured to drive the semiconductor light sources of each sub module simultaneously, wherein the sub modules and the electrical driver are arranged such that the processing surface of the wafer is homogeneously heated to a predefined temperature, a processing temperature being at least 100° C.; and
a reactor chamber, wherein the heating system is configured to heat at least one wafer within the reactor chamber.
4. The heating system according to claim 2 , wherein the heating system comprises at least a first group of sub modules with at least one sub module and at least a second group of sub modules with at least one sub module, the first group of sub modules being adapted to heat the whole heating surface, and the at least one sub module of the second group of sub modules being adapted to heat a part of the heating surface, and the electrical driver being adapted to drive the at least one sub module of the second group of sub modules independently from the sub module of the first group of sub modules.
5. The heating system according to claim 4 , wherein the second group of sub modules comprises at least two sub modules, each sub module of the second group of sub modules being adapted to heat a different part of the heating surface such that the whole heating surface is heated by the sub modules of the second group of sub modules, and wherein the electrical driver is adapted to drive each sub module of the second group of sub modules independently from the other sub modules of the second group of sub modules.
6. The heating system according to claim 4 , wherein the second group of sub modules comprises at least two sub modules, each sub module of the second group of sub modules being adapted to heat the complete heating surface, wherein the sub modules of the second group of sub modules are adapted to provide a different intensity distribution on the heating surface, and wherein the electrical driver is adapted to drive each sub module of the second group of sub modules independently from the other sub modules of the second group of sub modules.
7. The heating system according to claim 5 , wherein at least a part of the sub modules of the first group or the second group of sub modules comprises at least one temperature sensor being adapted to determine the temperature at a part of the heating surface illuminated by the respective sub module such that the homogeneity of the temperature distribution of the object can be monitored.
8. The heating system according to claim 7 , wherein the temperature sensors are optical sensors measuring the temperature at a different wavelength as a wavelength of light emitted by the semiconductor light sources.
9. The heating system according to claim 2 , wherein the heating system comprises at least 50000 semiconductor light sources.
10. The heating system according to claim 2 , wherein the heating system is adapted such that the intensity distribution provided by the semiconductor light sources scans the heating surface of the object.
11. The heating system according to claim 2 , wherein the heating system comprises a heating module for providing a first temperature distribution of the object, and the heating module and the semiconductor light sources are adapted to provide a homogeneous temperature distribution at the processing temperature.
12. The reactor according to claim 3 , wherein the reactor chamber comprises at least one reactor window, and the heating system is adapted to heat the wafer by irradiating light via the reactor window.
13. The reactor according to claim 12 , wherein the reactor chamber comprises one reactor window for each sub module.