Chenming Hu

Bio: Chenming Hu is an academic researcher from University of California, Berkeley. The author has contributed to research in topics: MOSFET & Gate oxide. The author has an hindex of 119, co-authored 1296 publications receiving 57264 citations. Previous affiliations of Chenming Hu include Motorola & National Chiao Tung University.

Optimization of gate oxide N/sub 2/O anneal for CMOSFET's at room and cryogenic temperatures

Abstract: This paper presents a study of the impact of gate-oxide N/sub 2/O anneal on CMOSFET's characteristics, device reliability and inverter speed at 300 K and 85 K. Two oxide thicknesses (60 and 110 /spl Aring/) and five N/sub 2/O anneal conditions (900/spl sim/950/spl deg/C, 5/spl sim/40 min) plus nonnitrided process and channel lengths from 0.2 to 2 /spl mu/m were studied to establish the correlation between the nitrogen concentration at Si/SiO/sub 2/ interface and the relative merits of the resultant devices. We concluded that one simple post-oxidation N/sub 2/O anneal step can increase CMOSFET's lifetime by 4/spl sim/10 times, effectively suppress boron penetration from the P/sup +/ poly-Si gate of P-MOSFET's without sacrificing CMOS inverter speed. We also found that the benefits in terms of the improved interface hardness and charge trapping characteristic still exist at cryogenic temperature. All these improvements are found to be closely correlated to the nitrogen concentration incorporated at the Si/SiO/sub 2/ interface. The optimal N/sub 2/O anneal occurs somewhere at around 2% of nitrogen incorporation at Si/SiO/sub 2/ interface which can be realized by annealing 60/spl sim/110 /spl Aring/ oxides at 950/spl deg/C for 5 min or 900/spl deg/C for 20 min. >

Intra-field gate CD variability and its impact on circuit performance

Abstract: Statistical analysis of an advanced CMOS process reveals a significant systematic within-field variability of gate CD strongly dependent on the local layout patterns We present a novel modeling methodology for accurate prediction of the effect of such CD variability on circuit performance that enables statistical design for increased performance and yield We also propose a mask-level gate CD correction algorithm allowing significant reduction of overall variability and provide a model to evaluate the effectiveness of correction

Hot Electrons as the Dominant Source of Degradation for Sub-5nm HZO FeFETs

Abstract: In this work, we demonstrate FDSOI ferroelectric FETs (FeFETs) incorporating 4.5 nm hafnium zirconium oxide, which show a ~0.5V memory window at +/-3.3V and a program/erase speed of 1 $\mu \mathrm{s}$ . In typical FeFETs where $\geq 9$ nm thick ferroelectric (FE) gate oxides have been used, bulk charge trapping has been identified as the main mechanism for endurance degradation and shrinkage of the memory window (MW). By contrast, we find that the role of bulk trapping in our devices with a much thinner FE layer is minimal. Through a combination of cryogenic temperature-dependent electrical measurements and simulations using the Ginestra ™ modeling platform, we identify and prove that hot electron-induced hole damage during the application of negative gate biases is the primary source of endurance degradation and MW closure in FeFETs with scaled oxide layers.

A Predictive Tunnel FET Compact Model With Atomistic Simulation Validation

Abstract: A predictive tunnel FET compact model is proposed. Gaussian quadrature method is used to overcome the challenge of integration. This provides the flexibility to use Wentzel–Kramers–Brillouin under spatially varying electric field, to incorporate effective band edge states broadening, and to evaluate the drain current by Landauer equation with consideration of electron reflection at the tunnel junction. The model not only shows good accuracy, speed, and smoothness, but is also some predictive capability so that the effects of changing material parameters on IC characteristics are well captured. The model is validated with atomistic simulation data for several materials.

Noise overshoot at drain current kink in SOI MOSFET

Abstract: The bias dependence of the drain current noise power of SOI (silicon-on-insulator) MOSFETs was studied, and low frequency noise overshoot at the drain current was observed. The overshoot has a width of about 0.7 V and exhibits a peak noise power which is two orders of magnitude higher than the normal noise level. The SOI devices used in this study were N-channel polysilicon gate MOSFETs on SIMOX (separation by implantation of oxygen) wafers fabricated with conventional submicron CMOS technology. The SOI film thickness, the buried-oxide thickness, and the gate oxide are 100 nm, 300 nm, and 11.5 nm, respectively. A computer-controlled test system was used to conduct the I-V and noise measurement automatically. A model explaining the occurrence of the noise overshoot and the noise peak is proposed. >

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

High-κ gate dielectrics: Current status and materials properties considerations

Abstract: Many materials systems are currently under consideration as potential replacements for SiO2 as the gate dielectric material for sub-0.1 μm complementary metal–oxide–semiconductor (CMOS) technology. A systematic consideration of the required properties of gate dielectrics indicates that the key guidelines for selecting an alternative gate dielectric are (a) permittivity, band gap, and band alignment to silicon, (b) thermodynamic stability, (c) film morphology, (d) interface quality, (e) compatibility with the current or expected materials to be used in processing for CMOS devices, (f) process compatibility, and (g) reliability. Many dielectrics appear favorable in some of these areas, but very few materials are promising with respect to all of these guidelines. A review of current work and literature in the area of alternate gate dielectrics is given. Based on reported results and fundamental considerations, the pseudobinary materials systems offer large flexibility and show the most promise toward success...

Design of Analog CMOS Integrated Circuits

Abstract: The CMOS technology area has quickly grown, calling for a new text--and here it is, covering the analysis and design of CMOS integrated circuits that practicing engineers need to master to succeed. Filled with many examples and chapter-ending problems, the book not only describes the thought process behind each circuit topology, but also considers the rationale behind each modification. The analysis and design techniques focus on CMOS circuits but also apply to other IC technologies. Table of contents 1 Introduction to Analog Design 2 Basic MOS Device Physics 3 Single-Stage Amplifiers 4 Differential Amplifiers 5 Passive and Active Current Mirrors 6 Frequency Response of Amplifiers 7 Noise 8 Feedback 9 Operational Amplifiers 10 Stability and Frequency Compensation 11 Bandgap References 12 Introduction to Switched-Capacitor Circuits 13 Nonlinearity and Mismatch 14 Oscillators 15 Phase-Locked Loops 16 Short-Channel Effects and Device Models 17 CMOS Processing Technology 18 Layout and Packaging

Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic Applications

Abstract: Nanocrystals (NCs) discussed in this Review are tiny crystals of metals, semiconductors, and magnetic material consisting of hundreds to a few thousand atoms each. Their size ranges from 2-3 to about 20 nm. What is special about this size regime that placed NCs among the hottest research topics of the last decades? The quantum mechanical coupling * To whom correspondence should be addressed. E-mail: dvtalapin@uchicago.edu. † The University of Chicago. ‡ Argonne National Lab. Chem. Rev. 2010, 110, 389–458 389