US 4,680,451 A · Apparatus using high intensity CW lamps for improved heat treating of semiconductor wafers

Abstract

Radiation heating of a semiconductor wafer employs first and second pluralities of spaced and skewed lamps. Lamps in each plurality are grouped beginning with the innermost lamps and extending to the outermost lamps. Each group of lamps in one plurality of lamps are interconnected with a group of lamps in the other plurality of lamps whereby the interconnected groups of lamps are simultaneously and equally energized. Lamp voltage is modulated in accordance with a preestablished table for each size of wafer and temperature cycle. Alternatively, temperature sensors can be employed to provide feedback to a computer controlled modulator. The lamps in the different groups can be selected to have different steady state power intensities for a given voltage to thereby establish a desired temperature gradient.

Claims22

Dependent claims

Apparatus for heating semiconductor wafers of various diameters and establishing desired radial temperature gradients comprising

a first plurality of parallel lamps,
a second plurality of parallel lamps, said second plurality of lamps being spaced from and skewed with respect to said first plurality of lamps whereby a semiconductor wafer can be positioned therebetween,
means electrically connecting pairs of lamps in said first plurality of lamps beginning with innermost lamps and extending outwardly and means electrically connecting pairs of lamps in said second plurality of lamps, beginning with innermost lamps and extending outwardly, and
means electrically interconnecting each pair of electrically connected lamps in said first plurality of lamps with a pair of electrically connected lamps in said second plurality of lamps whereby the interconnected pairs of lamps are simultaneously and equally energized to establish desired temperature gradients.

1 more element

Dependencies are inferred from the claim text.

Apparatus using high intensity CW lamps for improved heat treating of semiconductor wafers

Life of this patent

Apparatus using high intensity CW lamps for improved heat treating of semiconductor wafers

Life of this patent

Abstract

Claims22