This paper investigates the work function adjustment of a full silicidation （Ni-FUSI） metal gate. It is found that implanting dopant into poly-Si before silicidation can modulate the work function of a Ni-FUSI metal...This paper investigates the work function adjustment of a full silicidation （Ni-FUSI） metal gate. It is found that implanting dopant into poly-Si before silicidation can modulate the work function of a Ni-FUSI metal gate efficiently. With the implantation of p-type or n-type dopants,such as BF2 ,As,and P,the work function of a Ni-FUSI metal gate can be made higher or lower to satisfy the requirement of pMOS or nMOS, respectively. But implanting a high dose of As into a poly-Si gate before silicidation will cause the delamination effect and EOT loss,and thus As dopant is not suitable to be used to adjust the work function of a Ni-FUSI metal gate. Due to the EOT reduction in the FUSI Process,the gate leakage current of a FUSI metal gate capacitor is larger than that of a poly-Si gate capacitor.展开更多
Nickel fully silicided（Ni-FUSI） gate material has been fabricated on a HfO2 surface to form a Ni-FUSI gate/HfO2/Al（MIS） structure by using an ultra-high vacuum e-beam evaporation（EBV） method followed by a one st...Nickel fully silicided（Ni-FUSI） gate material has been fabricated on a HfO2 surface to form a Ni-FUSI gate/HfO2/Al（MIS） structure by using an ultra-high vacuum e-beam evaporation（EBV） method followed by a one step rapid thermal annealing（RTA） treatment.X-ray diffraction（XRD） and Raman spectroscopy were used to reveal the microstructures and electrical properties of the MIS structure.Results show that a one step post RTA treatment is enough to promote the full reaction of nickel silicide,compared with multiple RTA treatments. Furthermore,the HfO2 gate dielectric film is sensitive to heat treatment,and multiple RTA treatments can damage the electrical properties of the HfO2 film rather than improve them.By optimization of the sample fabrication technique,the MIS capacitor produces good high-frequency capacitance-voltage curves with a hysteresis of 30 mV, a work function of about 5.44-5.53 eV and leakage current density of only 1.45×10^（-8） A/cm^2 at -1V gate bias.展开更多
随着超大规模集成电路技术的发展,CMOS器件的制备过程需要同时引入金属栅和超浅结等新的先进工艺技术,因此各种新工艺的兼容性研究具有重要意义.本文研究了超浅结工艺中使用的锗预非晶化对镍硅(N iS i)金属栅功函数的影响.对具有不同剂...随着超大规模集成电路技术的发展,CMOS器件的制备过程需要同时引入金属栅和超浅结等新的先进工艺技术,因此各种新工艺的兼容性研究具有重要意义.本文研究了超浅结工艺中使用的锗预非晶化对镍硅(N iS i)金属栅功函数的影响.对具有不同剂量Ge注入的N iS i金属栅MOS电容样品的研究表明,锗预非晶化采用的Ge注入对N iS i金属栅的功函数影响很小(小于0.03eV),而且Ge注入也不会导致氧化层中固定电荷以及氧化层和硅衬底之间界面态的增加.这些结果表明,在自对准的先进CMOS工艺中,N iS i金属栅工艺和锗预非晶化超浅结工艺可以互相兼容.展开更多
This paper investigates the capacitance-voltage （C-V） measurement on fully silicided （FUSI） gated metal-oxide-semiconductor （MOS） capacitors and the applicability of MOS capacitor models. When the oxide leakage ...This paper investigates the capacitance-voltage （C-V） measurement on fully silicided （FUSI） gated metal-oxide-semiconductor （MOS） capacitors and the applicability of MOS capacitor models. When the oxide leakage current of an MOS capacitor is large, two-element parallel or series model cannot be used to obtain its real C-V characteristic. A three-element model simultaneously consisting of parallel conductance and series resistance or a four-element model with further consideration of a series inductance should be used. We employed the threeelement and the four-element models with the help of two-frequency technique to measure the Ni FUSI gated MOS capacitors. The results indicate that the capacitance of the MOS capacitors extracted by the three-element model still shows some frequency dispersion, while that extracted by the four-element model is close to the real capacitance, showing little frequency dispersion. The obtained capacitance can be used to calculate the dielectric thickness with quantum effect correction by NCSU C-V program. We also investigated the influence of MOS capacitor＇s area on the measurement accuracy. The results indicate that the decrease of capacitor area can reduce the dissipation factor and improve the measurement accuracy. As a result, the frequency dispersion of the measured capacitance is significantly reduced, and real C-V characteristic can be obtained directly by the series model. In addition, this paper investigates the quasi-static C-V measurement and the photonic high-frequency C-V measurement on Ni FUSI metal gated MOS capacitor with a thin leaky oxide. The results indicate that the large tunneling current through the gate oxide significantly perturbs the accurate measurement of the displacement current, which is essential for the quasi-static C-V measurement. On the other hand, the photonic high-frequency C-V measurement can bypass the leakage problem, and get reliable low-frequency C-V characteristic, which can be used to evaluate whether the full silicidation has completed or not, and to extract the interface trap density of the SiO2/Si interface.展开更多
文摘This paper investigates the work function adjustment of a full silicidation （Ni-FUSI） metal gate. It is found that implanting dopant into poly-Si before silicidation can modulate the work function of a Ni-FUSI metal gate efficiently. With the implantation of p-type or n-type dopants,such as BF2 ,As,and P,the work function of a Ni-FUSI metal gate can be made higher or lower to satisfy the requirement of pMOS or nMOS, respectively. But implanting a high dose of As into a poly-Si gate before silicidation will cause the delamination effect and EOT loss,and thus As dopant is not suitable to be used to adjust the work function of a Ni-FUSI metal gate. Due to the EOT reduction in the FUSI Process,the gate leakage current of a FUSI metal gate capacitor is larger than that of a poly-Si gate capacitor.
基金Project supported by the National Science Foundation of China(No.10775166)the National Natural Science Foundation of China(No. 60807002)the Shanghai Natural Science Foundation,China(No.09ZR1437700)
文摘Nickel fully silicided（Ni-FUSI） gate material has been fabricated on a HfO2 surface to form a Ni-FUSI gate/HfO2/Al（MIS） structure by using an ultra-high vacuum e-beam evaporation（EBV） method followed by a one step rapid thermal annealing（RTA） treatment.X-ray diffraction（XRD） and Raman spectroscopy were used to reveal the microstructures and electrical properties of the MIS structure.Results show that a one step post RTA treatment is enough to promote the full reaction of nickel silicide,compared with multiple RTA treatments. Furthermore,the HfO2 gate dielectric film is sensitive to heat treatment,and multiple RTA treatments can damage the electrical properties of the HfO2 film rather than improve them.By optimization of the sample fabrication technique,the MIS capacitor produces good high-frequency capacitance-voltage curves with a hysteresis of 30 mV, a work function of about 5.44-5.53 eV and leakage current density of only 1.45×10^（-8） A/cm^2 at -1V gate bias.
文摘随着超大规模集成电路技术的发展,CMOS器件的制备过程需要同时引入金属栅和超浅结等新的先进工艺技术,因此各种新工艺的兼容性研究具有重要意义.本文研究了超浅结工艺中使用的锗预非晶化对镍硅(N iS i)金属栅功函数的影响.对具有不同剂量Ge注入的N iS i金属栅MOS电容样品的研究表明,锗预非晶化采用的Ge注入对N iS i金属栅的功函数影响很小(小于0.03eV),而且Ge注入也不会导致氧化层中固定电荷以及氧化层和硅衬底之间界面态的增加.这些结果表明,在自对准的先进CMOS工艺中,N iS i金属栅工艺和锗预非晶化超浅结工艺可以互相兼容.
基金supported by the National Natural Science Foundation of China (Nos. 60576029, 90607018)the Science and TechnologyCommittee of Shanghai Municipality (No. 07QA14004)+1 种基金the Shanghai-Applied Materials Research Development Fund (No. 07SA06)Fok Ying Tong Education Foundation (No. 114006).
文摘This paper investigates the capacitance-voltage （C-V） measurement on fully silicided （FUSI） gated metal-oxide-semiconductor （MOS） capacitors and the applicability of MOS capacitor models. When the oxide leakage current of an MOS capacitor is large, two-element parallel or series model cannot be used to obtain its real C-V characteristic. A three-element model simultaneously consisting of parallel conductance and series resistance or a four-element model with further consideration of a series inductance should be used. We employed the threeelement and the four-element models with the help of two-frequency technique to measure the Ni FUSI gated MOS capacitors. The results indicate that the capacitance of the MOS capacitors extracted by the three-element model still shows some frequency dispersion, while that extracted by the four-element model is close to the real capacitance, showing little frequency dispersion. The obtained capacitance can be used to calculate the dielectric thickness with quantum effect correction by NCSU C-V program. We also investigated the influence of MOS capacitor＇s area on the measurement accuracy. The results indicate that the decrease of capacitor area can reduce the dissipation factor and improve the measurement accuracy. As a result, the frequency dispersion of the measured capacitance is significantly reduced, and real C-V characteristic can be obtained directly by the series model. In addition, this paper investigates the quasi-static C-V measurement and the photonic high-frequency C-V measurement on Ni FUSI metal gated MOS capacitor with a thin leaky oxide. The results indicate that the large tunneling current through the gate oxide significantly perturbs the accurate measurement of the displacement current, which is essential for the quasi-static C-V measurement. On the other hand, the photonic high-frequency C-V measurement can bypass the leakage problem, and get reliable low-frequency C-V characteristic, which can be used to evaluate whether the full silicidation has completed or not, and to extract the interface trap density of the SiO2/Si interface.
