Peng-Fu Hsu

32nm gate-first high-k/metal-gate technology for high performance low power applications

A 32 nm gate-first high-k/metal-gate technology is demonstrated with the strongest performance reported to date to the best of our knowledge. Drive currents of 1340/940 muA/mum (n/p) are achieved at Ioff=100 nA/mum, Vdd=1 V, 30 nm physical gate length and 130 nm gate pitch. This technology also provides a high-Vt solution for high-performance low-power applications with its high drive currents of 1020/700 muA/mum (n/p) at total Ioff ~1 nA/mum @ Vdd = 1V. Low sub-threshold leakage was achieved while successfully containing Iboff and Igoff well below 1 nA/um. Ultra high density 0.15 um2 SRAM cell is fabricated by high NA 193 nm immersion lithography. Functional 2 Mb SRAM test-chip in 32 nm design rule has been demonstrated with a controllable manufacturing window.

BTI Reliability of Dual Metal Gate CMOSFETs with Hf-based High-k Gate Dielectrics

This paper reports the BTI reliability of dual metal gate CMOSFETs with Hf-based dielectrics including HfO2 and HfSiON. Severer PBTI degradation was observed on HfO2 NMOSFETs and two NBTI degradation behaviors were observed on HfO2 pMOSFET. The strain effect and channel length dependence on BTI were also investigated. Mechanical strain degrades NBTI but has no effect on PBTI. As channel length scaling down, both PBTI and NBTI are mitigated.

BTI and Electron Trapping in Hf-based Dielectrics with Dual Metal Gates

In Hf-based stacks with TaC and MoNx dual metal gates, PBTI is found to be a concern. Although HfSiON reduces PBTI, worse NBTI by nitridation poses a potential issue. NBTI is also degraded by channel strain. A new pulse BTI technique is presented for electron trapping, which demonstrates the minimization of de-trapping and is used to simultaneously characterize fast and slow trapping components. Electron trapping characteristics on IL and HK thickness were also studied. It is revealed that fast trapping is from tunneling mechanism and the de-trapping behavior during stress plays important role in slow trap generation