Journal of Vacuum Science & Technology A, Vol.20, No.3, 1030-1033, 2002
Design of high speed Si/SiGe heterojunction complementary metal-oxide-semiconductor field effect transistors with reduced short-channel effects
By taking advantages of higher carrier mobility and bandgap engineering in the Si/SiGe system, we explore the channel and source/drain (S/D) designs for Si/SiGe heterojunction complementary metal-oxide-semiconductor field effect transistors (CMOSFETs). A planar CMOS structure is proposed in which a strained SiGe layer (the hole channel) and a strained Si layer (the electron channel) grown on relaxed SiGe wells are designed for p- and n-MOSFETs, respectively, to provide better current drive capability. On the other hand, a strained-SiGe S/D heterojunction is also included in the CMOSFET device structure in that the band offset between S/D and the channel is found to be very effective in suppressing short-channel effects such as drain-induced barrier lowering/bulk punchthrough and drain leakage. With proper structure design, the near symmetrical n-MOS/p-MOS V-T, enhanced current-drive capability and reduced short channel effects are achievable within the proposed planar structure.