Leakage Current Analysis Method for Metal Insulator Semiconductor Capacitors Through Low-Frequency Noise Measurement.

Use of thinner oxides to improve the operating speed of a complementary metal-oxidesemiconductor (CMOS) device causes serious gate leakage problems. Leakage current of the dielectric analysis method has I-V, C-V, and charge pumping, but the procedure is very complicated. In this premier work, we analyzed the leakage current of metal insulator semiconductor (MIS) capacitors with different initiators through low-frequency noise (LFN) measurement with simplicity and high sensitivity. The LFN measurement results show a correlation between power spectral density (SIG) and gate leakage current (IG). MIS capacitors of hafnium zirconium silicate (HZS, (HfZrO₄)1-x (SiO₂)x) were used for the experiments with varying SiO₂ ratio (x = 0, 0.1, 0.2) of hafnium zirconium oxide (HZO, HfZrO₄). As the SiO₂ ratio increased, the leakage current decreased according to J-V measurement. Further, the C-V measurement confirmed that the oxide-trapped charge (Not) increased with increasing SiO₂ ratio. Finally, the LFN measurement method revealed that the cause of leakage current reduction was trap density reduction of the insulator.