High-k metal gate fundamental learning and multi-V<inf>t</inf> options for stacked nanosheet gate-all-around transistor

State of the Art and Future Perspectives in Advanced CMOS Technology

“…With CMOS technology development, the reliability issues of advanced CMOS technology are becoming more challenging and complicated due to the novel material, novel process and novel device structure, e.g., Ge/GeSi channels, atom layer etching (ALE) technology, nanowires and nanosheets, etc., specially for 5 nm node and beyond [ 287 , 288 , 289 , 290 ]. Next, the transistor reliability challenge of advanced CMOS will be discussed.…”

“…Recently, novel devices such as FinFETs, nanowires, and nanosheets, as the best candidates for advanced CMOS technology, have been widely studied [ 287 , 288 ]. In order to meet the better performance of novel devices, advanced processes e.g., filling and etching in 3D device structure, are proposed [ 291 , 292 ].…”

“…Recently, novel devices such as FinFETs, nanowires, and nanosheets, as the best candidates for advanced CMOS technology, have been widely studied [287,288]. In order to meet the better Sub-nm barrier is urgently demanded for ultra-scaled interconnects in the near future.…”

Miniaturization of CMOS

“…In advanced CMOS technology, in order to reduce the influence of the thermal budget on junction and channel quality, introducing the novel materials and processes are necessary in gate engineering. Therefore, the dipole formation in the gate stack is widely applied in the Replacement Metal Gate (RMG) process [168,169,170,171,172,173]. Usually, Lanthanum (La) and Aluminum (Al) are used to tune threshold voltage for NFET and PFET due to the different dipole polarity [168,169,170,171].…”

“…This includes metal deposition (La or Al) and annealing treatment with or without a capping layer [168]. It has been reported that La induced dipole effectively, which makes V T decrease and positive bias temperature instability (PBTI) improve, but NBTI is worsened [168,169]. Meanwhile, the Al induced dipole increases V T and BTI becomes worse as well.…”