Zbigniew Lisik

Optical versus electrical interconnections for clock distribution networks in new VLSI technologies

Interconnects constitute a severe impediment to the future progress of VLSI integrated systems technology. The use of optics is considered to be an alternative solution that could overcome the limitations of metallic interconnects. Clock distribution networks could particularly benefit from this technology. In this paper , we present a quantitative analysis of the performance gains of using optical interconnect for clock distribution in terms of power and frequency. We present detailed comparative simulations of the features of optical and electrical H-tree clock networks.

Cooling Microstructure for Automotive Electronic Module

The paper presents the general overview of the cooling microstructure concept dedicated for automotive electronic systems. It introduces the first design stage of the micro heat sink and presents preliminary simulations that consider adaptation of automotive coolants. The theoretical discussion is supported by simulations and calculations that were led with the aid of ANSYS software.

Different Approaches for Clock Skew Analysis in Present and Future Synchronous IC's

One of the major performance limitations in chip designs is clock skew, the uncertainty in arrival times between a pair of clocks. Clock skew can limit overall circuit performance, or even cause functional errors. The main goal of this paper is to analyse and compare the most popular analytical models for estimating the clock skew for present and future VLSI systems. These models are compared for a generic global clock distribution network (an H-tree) with a JAVA program. Finally based on the presented models, a prevision for the clock skew value in upcoming technology nodes will be given.

The numerical approach to analysis of microchannel cooling systems

The paper deals with microchannel cooling where water is the cooling liquid. ANSYS software and CFDRC-ACE one were used to analyse the flows and the origin of large amount of heat that can be overtaken from the chip when microchannels are applied. The concept of microscale heat transfer coefficient is discussed. The phenomena taking place in microchannel flows are simulated and some conclusions are introduced to explain the results met in many references but still unexplained. In contrast to existing, standard methods, the new approach describes the local phenomena and is used in the further investigation of the cooling microstructure. An effect of its geometry on the total overtaken heat flux is analysed with respect to optimal conditions as well as to technological restrictions.

Super cooling structures for power electronics

The paper presents the microchannel cooling structure. This very efficient heat sink is dedicated for power electronic applications characterised by high heat flux densities combined with high overall power levels. The conducted measurements show that to meet both thermal and mechanical demands; the structure can achieve thermal resistance of 0.1 K/W

Clock Skew Analysis in Optical Clock Distribution Network

The optical clock distribution has been considered to alleviate limitations due to metallic interconnections for future generation of VLSI. It can be interesting only, if it is able to provide some substantial improvement of IC features. This paper studies the effects of the VLSI structure thermal gradients on the clock skew in optical clock distribution network CDN.

Simulation of parasitic interconnect capacitance for present and future ICs

The performance of modern integrated circuits is often determined by interconnect wiring requirements. Moreover, continuous scaling of VLSI circuits leads to an increase in the influence of interconnects on system performance. It is desired therefore, to calculate accurately its parasitic components, particularly wiring capacitance. In order to recognize which one from the most popular empirical approaches gives the evaluation of the total capacitance that suits to the real capacitance of the interconnect line, the numerical simulations based on the numerical solving of Maxwell equations have been employed.

Anisotropic drift diffusion model for 4H-, 6H-SiC devices simulation

In this paper, a CAD tool based on the drift-diffusion model was developed to simulate and compare the anisotropic behavior of 4H- and 6H-SiC hexagonal crystal polytypes used for device applications. The tool adopts a tensor formalism to describe the anisotropic nature that influence the dielectric permittivity constant, and both the electron and hole mobility constants. It also addresses the temperature dependence of all considered physical quantities such as the band gap, and takes into account SRH and Auger recombination, and incomplete ionization of dopants as well. Simulations have been performed for each prototype for the electric field parallel and orthogonal to the c-axis of the crystal, and a well set of values has been extracted from the I-V characteristics to show how the anisotropy may influence the electrostatic potential and the current density.

Power devices in Polish national silicon carbide program

Polish Government Program ldquoNew technologies based on silicon carbide and their applications in high frequency, high power and high temperature electronics rdquo covers an project package that consists of three general tasks. The contribution presents the overview of projects in the field dealing with the design and manufacturing of power SiC semiconductor devices.

Optimization of the On-Chip Optical Receivers

In this paper we present a general idea of on-chip optical interconnects, example simulations of the transimpedance amplifier circuits in CMOS and HBT technology and the optimization problems.