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In this paper, a new approach is presented for determining the substrate parameters of an arbitrary doping profile. It is general, technology independent, nonintrusive, and relies on simple direct-current measurements. A single measurement is required for uniform substrates, whereas two more measurements are needed for each additional layer in the multilayer case. Two different kernels are introduced for substrate resistance computation. One features a closed-form analytical solution of the Laplace equations defining the problem under study. The other relies on a geometric formulation of the current streamlines in order to compute the substrate resistance. Both simulations and measurements are exploited in order to show the validity of the proposed scheme. For measurements, data from literature are utilized and also data from a fabricated test chip. The results demonstrate that the proposed method succeeds in computing the substrate parameters fast and with high accuracy. In uniform substrates, the error falls to zero, whereas, in epitaxial substrates, the average error is kept bellow 4%. [ABSTRACT FROM AUTHOR]

Flaw profile characterization from nondestructive evaluation (NDE) measurements is a typical inverse problem. A novel transformation of this inverse problem into a tracking problem and subsequent application of a sequential Monte Carlo method called particle filtering has been proposed by the authors in an earlier publication. In this paper, the problem of flaw characterization from multisensor data is considered. The NDE inverse problem is posed as a statistical inverse problem, and particle filtering is modified to handle data from multiple measurement modes. The measurement modes are assumed to be independent of each other with principal component analysis used to legitimize the assumption of independence. The proposed particle-filter-based data fusion algorithm is applied to experimental low-frequency NDE data to investigate its feasibility. [ABSTRACT FROM AUTHOR]

In order to reduce the influence of axial displacement and/or to ease the assembly, certain capacitive angular sensors use symmetric designs limiting their absolute measuring range to (360°/n) where it is the number of blades. This paper presents a combined sensor that utilizes a Wiegand sensor to obtain ad. ditional information needed to resolve 360°. Since magnetic and electric fields required by the sensing principles do not interfere, one single rotor design can be used for both fields. When the receiver coil on a Wiegand sensor has to drive a current, this current influences the shape and duration of the pulse generated by the sensor. We found that shape and amplitude of the pulse vary depending on the strength of the applied fields and the location of the initial inverse nucleation. Since most of design optimization for capacitive sensors is done by means of simulations, an adequate model of the combined sensor is needed. For the capacitive part, numerical approches such as the finite element method are available. For the pulse wire part, an extended king model has been developed; results of measurements and numerical simulations are reported. [ABSTRACT FROM AUTHOR]