Marta Rencz

Design and test of MEMS

This paper deals with design, simulation and test of MEMS (microelectromechanical systems). Both existing tools and open research areas are addressed. An appropriate Computer-Aided Design (CAD) environment is presented. Similarities between the present development of MEMS and the development of microelectronics decades ago are pointed out, including the migration from point tools to CAD frameworks, testing and intellectual property (IP) issues.

Trends in Thermal Management of Microcircuits

With silicon microtechnology we intend to realize electrical networks: these are the integrated circuits. This goal however can never be obtained solely — a thermal network is also generated necessarily. The electrical parts dissipate heat, this will be the source of the thermal network. As a result the temperature of the chip will increase, changing the electrical parameters. In some cases this can even result in burning out the elements. With the decreasing chip feature sizes and package dimensions, with the increasing integration density the heat production per unit volume increases — continuously enlarging the severity of these problems.

Die Attach Quality Testing by Structure Function Evaluation

In this chapter simulation and measurement experiments prove that the structure function evaluation of the thermal transient testing is capable to locate die attach failure(s), even in case of stacked die packages. Both the strength and the location of the die attach failure may be determined with the methodology of a fast thermal transient measurement and the subsequent computer evaluation. The paper presents first the theoretical background of the method. After this, application on single die packages is presented. In the rest of the paper first simulation experiments show the feasibility of locating die attach problem in stacked die structures with the presented algorithm and a large number of measured experiments prove that the methodology is applicable also in practice. At the end of the chapter, in the evaluation of the methodology the special advantage of the method, that normally it does not require any additional circuit elements on any of the possibly-stacked-dies is also presented.

Compact dynamic thermal multiport models of packages for MEMS-package cosimulation

Co-simulation of MEMS and their packages is indispensable if the thermal behavior of the MEMS device is critical. For the co-simulation we need a reduced order thermal model of the package in the form of either behavioral or network model form. The paper presents a method for the automated generation of dynamic thermal multi-port models of packages, based on simulation results. The method is general, in will be applicable also for the direct generation of package multi- port network models of thermal transient testers.

From MEMS to the global simulation of SoCs

This paper is dealing with design, simulation and test of microsystems. Both existing tools and open research areas are addressed. All through the paper, similarities between the present development of MEMS and the development of microelectronics decades ago are pointed out, including the migration from point tools to Computer-Aided Design frameworks, testing, foundries/fabless business or IP issues. Specific aspects such as thermal simulation of microstructures and thermomechanical design at the package level. The conclusion is depicting a possible global simulation scheme integrating thermomechanical design at the package level. The conclusion is depicting a possible global simulation scheme integrating the needs of Systems on Chip multi language simulation together with the needs of MEMS multipurpose simulation.

Algorithmic and practical questions of electrothermal circuit simulation

In recent years great attention has been paid to the thermal issues in electronics design on system, board, package and chip level, including thermal and electro-thermal simulation of integrated circuits and MCM-s, or even integrated microsystems. In this paper we address some algorithmic issues regarding the method of simultaneous iteration. With the node reduction algorithm outlined here electro-thermal simulation of large problems becomes feasible. Besides this algorithmic innovation we provide a specification for a modular, platform independent electro-thermal simulator.

Tool and method for the theremal transient evaluation of packages

This paper presents a new concept for the thermal transient measurement of IC packages. The TTMK thermal transient test kit described here consists of a test chip, a dedicated software running on a PC and a special cable connecting the PC to the IC package which encapsulates the test chip. The function of the thermal transient test equipment is realized partly by the test chip itself and partly by the measuring software. The software performs both the control of the measurements and the evaluation of the results. The output of the evaluation software may be a compact model network or the structure function describing the properties of the heat conduction path. The use of the TTMK kit and the capabilities of the evaluation software are presented in this paper.