Atomic layer deposition of high-k dielectric layers on Ge and III-V MOS channels

Ge and III-V semiconductors are potential high performance channel materials for future CMOS devices. In this work, we have studied At. Layer Deposition (ALD) of high-k dielec. layers on Ge and GaAs substrates. We focus at the effect of the oxidant (H2O, O3, O2, O2 plasma) during gate stack formation. GeO2, obtained by Ge oxidn. in O2 or O3, is a promising passivation layer. The germanium oxide thickness can be scaled down below 1 nm, but such thin layers contain Ge in oxidn. states lower than 4+. Still, elec. results indicate that small amts. of Ge in oxidn. states lower than 4+ are not detrimental for device performance. Partial intermixing was obsd. for high-k dielec. and GeO2 or GaAsOx, suggesting possible correlations in the ALD growth mechanisms on Ge and GaAs substrates. [on SciFinder (R)

Electrical characteristics of 8-/spl Aring/ EOT HfO/sub 2//TaN low thermal-budget n-channel FETs with solid-phase epitaxially regrown junctions

International audienc

Understanding the materials, electrical and reliability impact of Al-addition to ZrO2 for BEOL compatible MIM capacitors

As operating frequency and circuit density of VLSI systems continue to increase, the L*di/dt induced voltage fluctuations in the power grid increasingly becomes a source of voltage/timing problems. On-chip decoupling capacitors, placed in close proximity to the power grid conductors, can offset parasitic inductances and thereby reduce the high frequency noise. High capacitance density MIM capacitors, placed between the last two metal layers, have been shown to be effective in achieving on-chip decoupling in high performance processors. There have been many reports in the literature on the use of high-k material such as Ta2O5, HfO2, ZrO2 for MIM capacitors [1-5]. A large number of reports of high-k MIM are focused on DRAM rather than decoupling capacitors applications [2-4]. One important difference between the DRAM capacitor module and decoupling capacitors is the thermal budget requirement. DRAM capacitors allow a higher thermal budget (~700°C) compared to embedded decoupling capacitors which must meet the BEOL thermal budget requirement (~400°C). We have recently reported an improved reliability by addition of Al into ZrO2 [6]. In this work, we report detailed material, electrical and further reliability characterization of ZrO2-based MIM capacitor capable of meeting stringent reliability requirement while maintaining compatibility with the backend processing thermal budget. A capacitor with >20fF/μm2 capacitance density and leakage current density <;100nA/cm2 meeting lifetime target (operated on both polarities) is demonstrated