A lamp (10), which can be used in rapid thermal processing (RTP), has a lamp envelope (12) arrayed along a longitudinal axis (14) and has a top (16) and a bottom (18). A first coiled-coil filament (20) having a first lead-in (20a) and a second coiled-coil filament (22) having a second lead-in (22a), are parallelly arrayed to each other and to the longitudinal axis (14) within the envelope (12). A serial connector (24) joins the first and second filaments; and an electrically insulating support (26) is positioned near the bottom (18) of the lamp envelope (12). The first lead-in (20a), the second lead-in (22a) and at least a portion (24a) of the serial connector (24) are sealed within the insulating support 26 whereby the first and second lead-ins (20a, 22a) and the at least a portion (24a) of the serial connector (24) provide the only support for the first and second filaments (20, 22). In a preferred embodiment, the first and second filaments (20, 22) have a wire diameter twice the diameter of a nominal CC6 filament.