Conference Paper

HfO2 and lanthanide-doped HfO2 MIM capacitors for RF/mixed IC applications

Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore
Conference: VLSI Technology, 2003. Digest of Technical Papers. 2003 Symposium on
Source: IEEE Xplore

ABSTRACT We demonstrate high quality HfO2-metal-insulator-metal (MIM) capacitors with a high capacitance of 4.7 fF/cm2 and a leakage current density of less than 10-8 A/cm2, meeting ITRS requirement for analog precision capacitor applications. In addition, we demonstrate that doping HfO2 with Lanthanide (Tb) at an optimum concentration improves both voltage linearity and leakage current density of HfO2 MIM capacitor, allowing further reduction of insulator thickness and achieving a capacitance density of 13.3 fF/μm2 with leakage current meeting requirements for RF bypass capacitors applications. These values are superior to that reported in the literature, suggesting the potential use of these dielectrics for future RF/mixed signal IC applications.

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