摘要:
ALD of HfxAlyCz films using hafnium chloride (HfCl4) and Trimethylaluminum (TMA) precursors can be combined with post-deposition anneal processes and ALD liners to control the device characteristics in high-k metal-gate devices. Variation of the HfCl4 pulse time allows for control of the Al % incorporation in the HfxAlyCz film in the range of 10-13%. Combinatorial process tools can be employed for rapid electrical and materials characterization of various materials stacks. The effective work function (EWF) in metal oxide semiconductor capacitor (MOSCAP) devices with the HfxAlyCz work function layer coupled with ALD deposited HfO2 high-k gate dielectric layers was quantified to be mid-gap at ˜4.6 eV. Thus, HfxAlyCz is a promising metal gate work function material allowing for the tuning of device threshold voltages (Vth) for anticipated multi-Vth integrated circuit (IC) devices.
摘要:
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.
摘要:
ALD of HfxAlyCz films using hafnium chloride (HfCl4) and Trimethylaluminum (TMA) precursors can be combined with post-deposition anneal processes and ALD liners to control the device characteristics in high-k metal-gate devices. Variation of the HfCl4 pulse time allows for control of the Al % incorporation in the HfxAlyCz film in the range of 10-13%. Combinatorial process tools can be employed for rapid electrical and materials characterization of various materials stacks. The effective work function (EWF) in metal oxide semiconductor capacitor (MOSCAP) devices with the HfxAlyCz work function layer coupled with ALD deposited HfO2 high-k gate dielectric layers was quantified to be mid-gap at ˜4.6 eV. Thus, HfxAlyCz is a promising metal gate work function material allowing for the tuning of device threshold voltages (Vth) for anticipated multi-Vth integrated circuit (IC) devices.
摘要:
A transistor device includes a gate structure positioned above a semiconductor substrate, and spaced-apart sidewall spacers positioned above the substrate and adjacent sidewalls of the gate structure. An internal sidewall surface of each of the spaced-apart sidewall spacers includes an upper sidewall surface portion and a lower sidewall surface portion positioned between the upper sidewall surface portion and a surface of the substrate, wherein a first lateral width between first upper ends of the upper sidewall surface portions is greater than a second lateral width between second upper ends of the lower sidewall surface portions.
摘要:
One method and device disclosed includes, among other things, forming a recessed sacrificial gate electrode having a recessed upper surface, performing at least one second etching process to define recessed sidewall spacers positioned adjacent the recessed sacrificial gate electrode, forming a plurality of sidewall spacers within a gate opening above the recessed sidewall spacers, wherein one of the spacers comprises a low-k insulating material that is positioned laterally between two other spacers and a gate cap layer, removing the recessed sacrificial gate electrode and forming a replacement gate structure in its place.
摘要:
Methods of scaling thickness of a gate dielectric structure that overlies a semiconductor substrate, methods of forming an integrated circuit, and integrated circuits are provided. A method of scaling thickness of a gate dielectric structure that overlies a semiconductor substrate includes providing the semiconductor substrate. An interfacial oxide layer is formed in or on the semiconductor substrate. A high-k dielectric layer is formed over the interfacial oxide layer. An oxygen reservoir is formed over at least a portion of the high-k dielectric layer. A sealant layer is formed over the oxygen reservoir. The semiconductor substrate including the oxygen reservoir disposed thereon is annealed to diffuse oxygen through the high-k dielectric layer and the interfacial oxide layer from the oxygen reservoir. Annealing extends the interfacial oxide layer into the semiconductor substrate at portions of the semiconductor substrate that underlie the oxygen reservoir to form a regrown interfacial region in or on the semiconductor substrate.
摘要:
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.
摘要:
A semiconductor comprising a multilayer structure which prevents oxidization of the titanium nitride layer that protects a high-K dielectric layer is provided. Replacement metal gates are over the multilayer structure. A sacrificial polysilicon gate structure is deposited first. The sacrificial polysilicon gate structure is then removed, and the various layers of the replacement metal gate structure are deposited in the space previously occupied by the sacrificial polysilicon gate structure.
摘要:
A gate structure of a semiconductor device having a NFET and a PFET, includes a lower layer of a hafnium-based dielectric over the gates of the NFET and PFET, and an upper layer of a lanthanide dielectric. The dielectrics are annealed to mix them above the NFET resulting in a lowered work function, and corresponding threshold voltage reduction. An annealed, relatively thick titanium nitride cap over the mixed dielectric above the NFET gate also lowers the work function and threshold voltage. Above the TiN cap and the hafnium-based dielectric over the PFET gate, is another layer of titanium nitride that has not been annealed. A conducting layer of tungsten covers the structure.
摘要:
A PFET-based semiconductor gate structure providing a midgap work function for threshold voltage control between that of a NFET and a PFET is created by including an annealed layer of relatively thick TiN to dominate and shift the overall work function down from that of PFET. The structure has a PFET base covered with a high-k dielectric, a layer of annealed TiN, a layer of unannealed TiN, a thin barrier over the unannealed TiN, and n-type metal over the thin barrier.