A semiconductor technology combines a normally off n-channel channel-junction insulated-gate field-effect transistor ("IGFET") (104) and an n-channel surface-channel IGFET (100 or 160) to reduce low-frequency 1/f noise. The channel-junction IGFET is normally of materially greater gate dielectric thickness than the surface-channel IGFET so as to operate across a greater voltage range than the surface-channel IGFET. Alternatively or additionally, the channel-junction IGFET may conduct current through a field-induced surface channel. A p-channel surface-channel IGFET (102 or 162), which is typically of approximately the same gate-dielectric thickness as the n-channel surface-channel IGFET, is preferably combined with the two n-channel IGFETs to produce a complementary-IGFET structure. A further p-channel IGFET (106, 180, 184, or 192), which is typically of approximately the same gate dielectric thickness as the n-channel channel-junction IGFET, is also preferably included. The further p-channel IGFET can be a surface-channel or channel-junction device.

 
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