Abstract: An integrated circuit product includes an NMOS transistor having a gate structure that includes an NMOS gate insulation layer, a first NMOS metal layer positioned on the NMOS gate insulation layer, an NMOS metal silicide material positioned above the first NMOS metal layer, and a layer of a second metal material positioned above and in contact with the NMOS gate insulation layer, the first NMOS metal layer, and the NMOS metal silicide layer. The PMOS transistor has a gate structure that includes a PMOS gate insulation layer, a first PMOS metal layer positioned on the PMOS gate insulation layer, a PMOS metal silicide material positioned above the first PMOS metal layer, and a layer of the second metal material positioned above and in contact with the PMOS gate insulation layer, the first PMOS metal layer, and the PMOS metal silicide layer.

Abstract: Devices with lightly-doped semiconductor channels (e.g., FinFETs) need mid-gap (˜4.6-4.7 eV) work-function layers, preferably with low resistivity and a wide process window, in the gate stack. Tantalum carbide (TaC) has a mid-gap work function that is insensitive to thickness. TaC can be deposited with good adhesion on high-k materials or on optional metal-nitride cap layers. TaC can also serve as the fill metal, or it can be used with other fills such as tungsten (W) or aluminum (Al). The TaC may be sputtered from a TaC target, deposited by ALD or CVD using TaCl4 and TMA, or produced by methane treatment of deposited Ta. Al may be added to tune the threshold voltage.

Abstract: An integrated circuit product includes an NMOS transistor having a gate structure that includes an NMOS gate insulation layer, a first NMOS metal layer positioned on the NMOS gate insulation layer, an NMOS metal silicide material positioned above the first NMOS metal layer, and a layer of a second metal material positioned above and in contact with the NMOS gate insulation layer, the first NMOS metal layer, and the NMOS metal silicide layer. The PMOS transistor has a gate structure that includes a PMOS gate insulation layer, a first PMOS metal layer positioned on the PMOS gate insulation layer, a PMOS metal silicide material positioned above the first PMOS metal layer, and a layer of the second metal material positioned above and in contact with the PMOS gate insulation layer, the first PMOS metal layer, and the PMOS metal silicide layer.

Abstract: One method for forming replacement gate structures for NMOS and PMOS transistors includes performing an etching process to remove a sacrificial gate structure for the NMOS and PMOS transistors to thereby define NMOS and PMOS gate cavities, depositing a gate insulation layer in the gate cavities, depositing a first metal layer on the gate insulation layer in the gate cavities, performing at least one process operation to form (1) an NMOS metal silicide material above the first metal layer within the NMOS gate cavity, the NMOS metal silicide material having a first amount of atomic silicon, and (2) a PMOS metal silicide material above the first metal layer within the PMOS gate cavity, the PMOS metal silicide material having a second amount of atomic silicon, and wherein the first and second amounts of atomic silicon are different, and forming gate cap layers within the NMOS and PMOS gate cavities.

Abstract: One method for forming replacement gate structures for NMOS and PMOS transistors includes performing an etching process to remove a sacrificial gate structure for the NMOS and PMOS transistors to thereby define NMOS and PMOS gate cavities, depositing a gate insulation layer in the gate cavities, depositing a first metal layer on the gate insulation layer in the gate cavities, performing at least one process operation to form (1) an NMOS metal silicide material above the first metal layer within the NMOS gate cavity, the NMOS metal silicide material having a first amount of atomic silicon, and (2) a PMOS metal silicide material above the first metal layer within the PMOS gate cavity, the PMOS metal silicide material having a second amount of atomic silicon, and wherein the first and second amounts of atomic silicon are different, and forming gate cap layers within the NMOS and PMOS gate cavities.

Abstract: Tungsten silicide layers can be used in CMOS transistors in which the work function of the tungsten silicide layers can be tuned for use in PMOS and NMOS devices. A co-sputtering approach can be used in which silicon and tungsten are deposited on a high dielectric constant gate dielectric layer. The tungsten silicide layer can be annealed at or above a critical temperature to optimize the resistivity of the tungsten silicide layer. In some embodiments, the concentration of as-deposited tungsten silicide can be between 50 at % silicon to 80 at % silicon. The critical temperatures can be lower at higher silicon concentration, such as 700 C. at 63 at % silicon to 600 C. at 74 at % silicon.