Reliability physics of ferroelectric/negative capacitance transistors for memory/logic applications: An integrative perspective

Abstract

Despite the remarkable development in ferroelectric HfO 2 -based FETs, key reliability challenges (e.g. endurance) may still limit their widespread adoption in memory and logic applications. In this paper, we present a simple theoretical frameworkbased on the Landau theory of phase transition -to design both ferroelectric FETs (FeFETs) and negative capacitance transistors (NCFETs) and investigate their reliability issues. For FeFETs, we analyze the role of interface and bulk traps on memory window closure to quantify endurance under different operating conditions. For NCFETs, we discuss the beneficial role of NC effect in reducing (or even eliminating) the persistent reliability issue of negative bias temperature instability (NBTI) that has plagued MOSFETs for decades. Both devices could also suffer from the Hot Atom Damage (HAD), i.e., switchinginduced bond dissociation during transient overshoot. We conclude by discussing how other reliability issues (e.g. TDDB, HCD, etc.) may also have to be reinterpreted for FE/NCFETs.

Phases in HfO2-Based Ferroelectric Thin Films and Their Integration in Low-Power Devices

“…The subsequent sections of this article focused on memory devices (FRAMs, FeFETs, and FTJs) using HfO 2 -based doped ferroelectrics. Further, the performance of these devices is severely affected by various practical and reliability issues, which are as follows Doped-HfO 2 ferroelectrics suffer from imprint (lateral shift of P vs E loops) and nonuniform orthorhombic phase.…”

“…Further, the performance of these devices is severely affected by various practical and reliability issues, which are as follows. 47 • Doped-Hf O 2 ferroelectrics suffer f rom imprint (lateral shif t of P vs E loops) and nonuniform orthorhombic phase. These issues can be addressed from various approaches.…”

An Aqueous Route to Oxygen-Deficient Wake-Up-Free La-Doped HfO2 Ferroelectrics for Negative Capacitance Field Effect Transistors

“…This helps in stabilizing negative capacitance. 48 These HLO/Al 2 O 3 film stacks were used in bottom gate top contact devices with an ∼50 nm IGZO channel (dimensions length/width: 10/15 μm/μm). All devices were characterized using I D vs V GS at a constant drain-tosource bias (V DS ) of 1 V. The sweep rate of the V GS ramp was ∼0.35 V/s with a 50 mV step; forward and reverse voltage sweeps were performed to assess the I vs V hysteresis.…”

“…The high-angle annular dark field (HAADF) imaging mode with a detector inner angle of ∼68 mrad was used to obtain atomic structure images of the samples. To distinguish crystal structures, position-averaged convergent beam electron diffraction (PACBED) and fast Fourier transform (FFT) analyses were subsequently conducted on the same regions observed by HAADF STEM. , Further, the chemical compositions at various depths of amorphous and crystalline HLO thin films were analyzed using depth profile X-ray photoelectron spectroscopy (XPS: ESCA 2000, MultiLab) with a monochromatic Al Kα X-ray source. The XPS spectra at different depths were recorded after etching with Ar for 300, 600, 900, and 1200 s. The recorded spectra were calibrated using the C 1s signature response at 284.6 eV.…”

Reliability of HfO2-Based Ferroelectric FETs: A Critical Review of Current and Future Challenges

“…The review/perspective articles in the literature mostly focus on performance metrics, and do not systematically discuss the FeFET reliability challenges and corresponding tradeoff between performance and reliability [7], [8], [15]- [20]. Only recently, the authors in [21] offered an integrated theoretical framework to analyze reliability issues of HfO2-FeFETs (and also negative capacitance FETs, NCFETs).…”