IC Technology CAD Overview

Integration of process, device and circuit simulation tools is desirable in modern process development and circuit design, as it allows rapid assessment of the impact of a new process or process change on circuit performance, [1]. This paper presents an efficient scheme for the extraction of MOSFET linear region SPICE level 3 parameters from numerical device simulations. Carrier concentrations, potential and mobility are used to derive a total of seven linear region parameters from three off-state bias points. This is in contrast to standard curve fitting techniques where twenty or, more on-state bias points would typically be used to obtain the required parameters.

Towards an intelligent CAD system for multilayer electromagnetic absorber design

LC-CAD: A CAD system for life cycle design

Integrating multiscale modeling and optimization for sustainable process development

An interdisciplinary approach to management allows for the integration of knowledge and tools of different fields of science into a unified methodology in order to improve the efficiency of resource management of different kinds of systems. In the conditions of global transformations, it is economic systems that have been significantly affected by external destabilizing factors. This determines the focus of attention on the need to develop tools for the modeling and optimization of economic systems, both in terms of organizational structure and in the context of resource management. The purpose of this review study is to identify the current gaps (shortcomings) in the scientific literature devoted to the issues of the modeling and optimization of economic systems using the tools of mass service theory. This article presents a critical analysis of approaches for the formulation of provisions on mass service systems in the context of resource management. On the one hand, modern works are characterized by the inclusion of an extensive number of random factors that determine the performance and efficiency of economic systems: the probability of delays and interruptions in mobile networks; the integration of order, inventory, and production management processes; the cost estimation of multi-server system operation; and randomness factors, customer activity, and resource constraints, among others. On the other hand, controversial points are identified. The analytical study carried out allows us to state that the prevailing majority of mass service models applied in relation to economic systems and resource supply optimization are devoted to Markov chain modeling. In terms of the chronology of the problems studied, there is a marked transition from modeling simple systems to complex mass service networks. In addition, we conclude that the complex architecture of modern economic systems opens up a wide research field for finding a methodology for assessing the dependence of the enterprise performance on the effect of optimization provided by using the provisions of mass service theory. This statement can be the basis for future research.

Furnace integration into processes justified by detailed calculation using a simple mathematical model

The aggressive downscaling of FET devices (FinFET, NanowireFET, NanosheetFET, to name a few) in past years has put a great emphasis on the need to come up with properly calibrated process and device simulation tools to predict performances, suggest processing options and even understand failure mechanisms. As their modeling is complex with multiple calibration parameters, adequate two- and three-dimensional characterization techniques have been identified as a necessity to achieve an accurate modeling and calibration of the complex physical mechanisms for scaled devices. In such scaled devices even the smallest variations of the structure dimensions (i.e., width or length, local interconnect or spacer, source/drain epi volumes, etc.), carrier distribution and/or activation rate can cause significant variations in the electrical properties.

In this chapter we explore some topics beyond traditional MCDM. First we explain in the simplest possible terms what multiobjective optimization is, and define the subject matter of this chapter. We discuss the role of tradeoffs and draw a distinction between tradeoffs-based versus tradeoffs-free thinking. Next, we introduce the concept of optimization and optimal systems design. Then we build the foundation of De novo programming, dealing with designing optimal systems in linear cases. Finally, we provide some numerical examples and discuss additional applications where optimal design and multiobjective optimization can be used.

A novel two-dimensional (2D) process simulator has been developed which can handle local oxidation, implantation through arbitrary mask edges, nonplanar surfaces, and high concentration diffusion. Through coupling of 2D process and device simulators, the sensitivity of perimeter junction capacitance and breakdown voltage to variations in boron channel-stop implantation dose and local oxidation time has been simulated for a standard NMOS technology. Experimental results using test structures have confirmed the simulations. It is shown that simple power-law dependencies as a function of the process variables give good agreement with the data.

This paper presents a framework for the system integration and optimization of a molten carbonate fuel cell (MCFC) working under stationary conditions using process integration. Here, the analysis is focused on two systems in terms of the efficiency and process requirements: (i) an MCFC system alone and (ii) an MCFC system integrated with the steam turbine cycle, now onwards referred to as fuel cell combined cycle system for electric power generation. In the first system, a steady state direct internal reforming MCFC system is being simulated using desulphurized natural gas. A heat exchanger network is developed using process integration so that a minimum amount of external thermal energy is provided to the fuel cell system for electric power generation. In the second analysis, a steam turbine system is added to the first (fuel cell) one to form a fuel cell combined cycle system. The procedure for developing a network of heat exchangers and proper integration of the steam turbine system with an optimized minimum temperature difference is discussed. The results of the study elucidate the advantages of properly designed fuel cell combined cycle system to reach power demand with 17% higher efficiency as compared with the system without a combined cycle.

Pinch Analysis and Process Integration: a User Guide on Process Integration for the Efficient Use of Energy

A simultaneous combination of scanning Kelvin probe microscopy and scanning atomic force microscopy has been applied to the problem of profiling dopant concentrations in two dimensions in silicon microstructures. By measuring the electrochemical potential difference which minimizes the electrostatic force between probe tip and sample surface, the work-function difference between the tip and surface is estimated. To the extent that this work-function difference is a consequence of the dopant concentration at or near the sample surface, doping profiles are inferred from the measurement. Structures examined and presented here include contact holes, and the technologically significant lightly doped drain of a metal–oxide–silicon field-effect transistor. Using this methodology, one can distinguish relative changes in dopant concentration with lateral resolution less than 100 nm. Sample preparation is minimal, and measurement time is fast compared to other techniques. The measurements have been compared to predictions based on two- and three-dimensional process and device simulation tools. The comparisons show that the technique is sensitive to changes in dopant concentration, from ≊1015 to 1020 cm−3, of less than 10% at these size scales. Suggestions to resolve absolute dopant concentration are made.

A novel buried-drain MOSFET (BDMOS) structure is presented which utilizes a double-implanted source region to achieve short-channel lengths. The fabrication sequence of a six-mask silicon-gate process shows the highlights of this new technology. Strong emphasis has been given on using process and device simulation tools, in order to optimize device performance. Experimental results on fabricated devices with source-drain distances between 0.5 and 3 µm and active channel lengths of 0.25 µm show the inherent potential of this new structure.

TCAD software needs equipment input settings and models to create the process environment for process and device simulation tools like TSUPREM4 and MEDICI. After optimisation the next step is the circuit simulation and design using software packages like SPICE. First using design of experiments-DOE and response surface modelling-RSM techniques we optimise the MOSFET characteristics and then we compare the transfer characteristics of n-type MOSFET, biased in the linear region, and obtained from package respectively TSUPREM4 and MEDICI with transfer characteristics from PSPICE. Using the PSPICE second level model for MOS transistor we obtain a good fit with MEDICI transfer characteristics.

In this paper, a simulation-based optimization methodology for nanoscale complementary metal-oxide-semiconductor (CMOS) device fabrication is advanced. Fluctuation of electrical characteristics is simultaneously considered and minimized in the optimization procedure. Integration of device and process simulation is implemented to evaluate device performances, where the hybrid intelligent approach enables us to extract optimal recipes which are subject to targeted device specification. Production of CMOS devices now enters the technology node of 65 nm; therefore, random-dopant-induced characteristic fluctuation should be minimized when a set of fabrication parameters is suggested. Verification of the optimization methodology is tested and performed for the 65-nm CMOS device. Compared with realistic fabricated and measured data, this approach can achieve the device characteristics; e.g., for the explored 65-nm n-type MOS field effect transistor, the on-state current > 0.35 mA/mum, the off-state current < 1.5e - 11 A/mum, and the threshold voltage = 0.43 V. Meanwhile, it reduces the threshold voltage fluctuation (sigma <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vth</sub> ~ 0.017 V). This approach provides an alternative to accelerate the tuning of process parameters and benefits manufacturing of nanoscale CMOS devices.