Abstract
We evaluate various metal gate/high-κ/Si capacitors by their resulting electrical characteristics. Therefore, we process MOS gate stacks incorporating aluminium (Al), nickel (Ni), titanium-nitride (TiN), and molybdenum (Mo) as the gate material, and metal organic chemical vapour deposited (MOCVD) ZrO2 and HfO2 as the gate dielectric, respectively. The influence of the processing sequence - especially of the thermal annealing treatment - on the electrical characteristics of the various gate stacks is being investigated. Whereas post metallization annealing in forming gas atmosphere improves capacitance-voltage behaviour (due to reduced interface-, and oxide charge density), current-voltage characteristics degrade due to a higher leakage current after thermal treatment at higher temperatures. The Flatband-voltage values for the TiN-, Mo-, and Ni-capacitors indicate mid-gap pinning of the metal gates, however, Ni seems to be thermally unstable on ZrO2, at least within the process scheme we applied.
Original language | English |
---|---|
Pages (from-to) | 1635-1638 |
Number of pages | 4 |
Journal | Microelectronic Engineering |
Volume | 84 |
Issue number | 5-8 |
DOIs | |
Publication status | Published - May 2007 |
Externally published | Yes |
Keywords
- HfO
- High-κ
- MOCVD
- Metal gate
- Processing
- ZrO