Apparatus and method for filtering light in a thermal processing chamber
First Claim
1. An apparatus for heat treating semiconductor devices comprising:
- a thermal processing chamber adapted to contain a semiconductor wafer;
a light source in communication with said thermal processing chamber, said light source comprising at least one lamp for emitting light energy into said chamber;
at least one radiation sensing device extending into said thermal processing chamber, said at least one radiation sensing device being configured to sense thermal radiation at a preselected wavelength, said at least one radiation sensing device for sensing radiation being emitted by a semiconductor wafer contained within said chamber;
a first spectral filter being positioned between said light source and said at least one radiation sensing device, said first spectral filter being configured to absorb thermal radiation being emitted by said light source at said preselected wavelength for preventing said thermal radiation from being detected by said at least one radiation sensing device; and
a second spectral filter spaced apart from said first spectral filter so as to define a cooling channel therebetween, said second spectral filter being positioned between said first spectral filter and said at least one radiation sensing device, said second spectral filter being substantially transparent to thermal radiation at said preselected wavelength.
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention is directed to an apparatus and process for filtering light in a thermal processing chamber. In particular, the apparatus of the present invention includes a first spectral filter spaced apart from a second spectral filter. The first spectral filter is spaced apart from the second spectral filter so as to define a cooling fluid channel therebetween through which a cooling fluid can be circulated. In order to prevent thermal radiation being emitted by the light source from interfering with the operation of a radiation sensing device contained in the chamber, the first spectral filter absorbs most of the thermal radiation being emitted by the light source at the operating wavelength of the radiation sensing device. The second spectral filter, on the other hand, is substantially transparent to thermal radiation at the operating wavelength of the radiation sensing device. If desired, various reflective coatings made from dielectric materials can also be applied to selected surfaces of the spectral filters to further prevent unwanted thermal radiation from being detected by the radiation sensing device and for preventing the spectral filters from increasing in temperature during operation of the chamber.
298 Citations
30 Claims
-
1. An apparatus for heat treating semiconductor devices comprising:
-
a thermal processing chamber adapted to contain a semiconductor wafer; a light source in communication with said thermal processing chamber, said light source comprising at least one lamp for emitting light energy into said chamber; at least one radiation sensing device extending into said thermal processing chamber, said at least one radiation sensing device being configured to sense thermal radiation at a preselected wavelength, said at least one radiation sensing device for sensing radiation being emitted by a semiconductor wafer contained within said chamber; a first spectral filter being positioned between said light source and said at least one radiation sensing device, said first spectral filter being configured to absorb thermal radiation being emitted by said light source at said preselected wavelength for preventing said thermal radiation from being detected by said at least one radiation sensing device; and a second spectral filter spaced apart from said first spectral filter so as to define a cooling channel therebetween, said second spectral filter being positioned between said first spectral filter and said at least one radiation sensing device, said second spectral filter being substantially transparent to thermal radiation at said preselected wavelength. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An apparatus for heat treating semiconductor devices comprising:
-
a thermal processing chamber adapted to contain a semiconductor wafer; a light source in communication with said thermal processing chamber, said light source comprising at least one lamp for emitting light energy into said chamber; at least one radiation sensing device located within said thermal processing chamber, said at least one radiation sensing device being configured to sense thermal radiation at a preselected wavelength, said at least one radiation sensing device for sensing thermal radiation being emitted by a semiconductor wafer contained within said chamber; and a first spectral filter spaced apart from a second spectral filter so as to define a cooling fluid channel therebetween, said first and second spectral filters being positioned between said light source and said at least one radiation sensing device for preventing thermal radiation being emitted by said light source at said preselected wavelength from being detected by said at least one radiation sensing device, said first and second spectral filters being positioned such that light energy being emitted by said light source first passes through said first spectral filter and then passes through said second spectral filter, said first and second spectral filters being made of silica, said first spectral filter containing a greater concentration of hydroxide ions than said second spectral filter. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. An apparatus for heat treating semiconductor devices comprising:
-
a thermal processing chamber adapted to contain a semiconductor wafer; a light source in communication with said thermal processing chamber, said light source comprising at least one lamp for emitting light energy into said chamber; at least one radiation sensing device located within said thermal processing chamber, said at least one radiation sensing device for sensing thermal radiation at a preselected wavelength, said at least one radiation sensing device for sensing thermal radiation being emitted by a semiconductor wafer contained within said chamber; and a spectral filter positioned between said light source and said at least one radiation sensing device, said spectral filter being configured to substantially prevent thermal radiation being emitted by said light source at said preselected wavelength from being detected by said at least one radiation sensing device, said spectral filter including a first outer surface facing said at least one radiation sensing device, said first outer surface being coated with a reflective coating, said reflective coating being configured to reflect thermal radiation at a wavelength range different than the preselected wavelength at which said radiation sensing device operates, said wavelength range being greater than about 4 microns, said reflective coating reflecting thermal radiation being emitted by a semiconductor wafer contained in said thermal processing chamber for preventing said spectral filter from absorbing said thermal radiation and increasing in temperature. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25)
-
-
26. An apparatus for heat treating semiconductor devices comprising:
-
a thermal processing chamber adapted to contain a semiconductor wafer; a light source in communication with said thermal processing chamber, said light source comprising at least one lamp for emitting light energy into said chamber; at least one radiation sensing device located within said processing chamber, said at least one radiation sensing device for sensing thermal radiation at a preselected wavelength, said at least one radiation sensing device for sensing thermal radiation being emitted by a semiconductor wafer contained within said chamber; and a spectral filter positioned between said light source and said at least one radiation sensing device, said spectral filter being configured to substantially prevent thermal radiation being emitted by said light source at said preselected wavelength from being detected by said at least one radiation sensing device, said spectral filter including a first surface facing said light source and a second surface facing said at least one radiation sensing device, said first surface being coated with a first reflective coating, said first reflective coating being configured to reflect thermal radiation at a wavelength greater than about 4 microns in order to prevent said spectral filter from increasing in temperature, said second surface being coated with a second reflective coating, said second reflective coating being configured to prevent thermal radiation at said preselected wavelength from being emitted by said spectral filter towards said at least one radiation sensing device. - View Dependent Claims (27, 28, 29, 30)
-
Specification