: We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN...: We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN and PVD-process top-TiN capping provide smaller effective work function (EWF), and a thicker TaN and ALD-process top-TiN capping provides a larger EWF; here, the EWF shifts are from 4.25 to 4.56 eV. A physical understanding of the dependence of the EWF on the top-TiN technology process and TaN thickness is proposed. Compared with PVD-TiN room temperature process, the ALD-TiN 400 ℃ process provides more thermal budget. It would also promote more Al atoms to diffuse into the top-TiN rather than the bottom-TiN. Meanwhile, the thicker TaN prevents the Al atoms diffusing into the bottom-TiN. These facts induce the EWF to increase.展开更多
Abstract: The effects of low temperature annealing, such as post high-k dielectric deposition annealing (PDA), post metal annealing (PMA) and forming gas annealing (FGA) on the electrical characteristics of a m...Abstract: The effects of low temperature annealing, such as post high-k dielectric deposition annealing (PDA), post metal annealing (PMA) and forming gas annealing (FGA) on the electrical characteristics of a metal-oxidesemiconductor (MOS) capacitor with a TiN metal gate and a Hf02 dielectric are systematically investigated. It can be found that the low temperature annealing can improve the capacitance-voltage hysteresis performance signifi- cantly at the cost of increasing gate leakage current. Moreover, FGA could effectively decrease the interfacial state density and oxygen vacancy density, and PDA could make the flat band positively shift which is suitable for P-type MOSs. Key words: ALD Hf02; TiN; low temperature annealing; hysteresis展开更多
基金Project supported by the Important National Science&Technology Specific Projects(No.2009ZX02035)the National Natural Science Foundation of China(Nos.61176091,61306129)
文摘: We introduced a TaN/TiAl/top-TiN triple-layer to modulate the effective work function of a TiN-based metal gate stack by varying the TaN thickness and top-TiN technology process. The results show that a thinner TaN and PVD-process top-TiN capping provide smaller effective work function (EWF), and a thicker TaN and ALD-process top-TiN capping provides a larger EWF; here, the EWF shifts are from 4.25 to 4.56 eV. A physical understanding of the dependence of the EWF on the top-TiN technology process and TaN thickness is proposed. Compared with PVD-TiN room temperature process, the ALD-TiN 400 ℃ process provides more thermal budget. It would also promote more Al atoms to diffuse into the top-TiN rather than the bottom-TiN. Meanwhile, the thicker TaN prevents the Al atoms diffusing into the bottom-TiN. These facts induce the EWF to increase.
基金supported by the Important National Science&Technology Specific Projects,China(No.2009ZX02035)the National Natural Science Foundation of China(Nos.61176091,50932001)
文摘Abstract: The effects of low temperature annealing, such as post high-k dielectric deposition annealing (PDA), post metal annealing (PMA) and forming gas annealing (FGA) on the electrical characteristics of a metal-oxidesemiconductor (MOS) capacitor with a TiN metal gate and a Hf02 dielectric are systematically investigated. It can be found that the low temperature annealing can improve the capacitance-voltage hysteresis performance signifi- cantly at the cost of increasing gate leakage current. Moreover, FGA could effectively decrease the interfacial state density and oxygen vacancy density, and PDA could make the flat band positively shift which is suitable for P-type MOSs. Key words: ALD Hf02; TiN; low temperature annealing; hysteresis