A tungsten-halogen electromagnetic radiation source has a sealed transparent aluminum oxynitride envelope defining an interior volume. At least one optical element is integrally formed into the aluminum oxynitride envelope. A tungsten filament is located in the aluminum oxynitride envelope. A fill gas in the interior volume contains at least a gaseous halogen compound.

A tungsten-halogen electromagnetic radiation source has a sealed transparent aluminum oxynitride envelope defining an interior volume. At least one optical element is integrally formed into the aluminum oxynitride envelope. A tungsten filament is located in the aluminum oxynitride envelope. A fill gas in the interior volume contains at least a gaseous halogen compound.

A lamp assembly for the lamp assembly adapted for use in a substrate thermal processing chamber to heat the substrate to temperatures up to at least about 1100 C. is disclosed. In one embodiment, the lamp assembly comprises a bulb enclosing at least one radiation generating filament attached to a pair of leads, the bulb having an inner surface and an outer surface, a lamp base configured to receive the pair of leads and at least a portion of the bulb having a surface treatment adapted to reflect light away from the lamp base. In another embodiment, a sleeve covers the lamp base, which has a cross-sectional area less than about 1.2 times the cross-sectional area of the bulb.

A lamp assembly for the lamp assembly adapted for use in a substrate thermal processing chamber to heat the substrate to temperatures up to at least about 1100 C. is disclosed. In one embodiment, the lamp assembly comprises a bulb enclosing at least one radiation generating filament attached to a pair of leads, the bulb having an inner surface and an outer surface, a lamp base configured to receive the pair of leads and at least a portion of the bulb having a surface treatment adapted to reflect light away from the lamp base. In another embodiment, a sleeve covers the lamp base, which has a cross-sectional area less than about 1.2 times the cross-sectional area of the bulb.