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The technology development cycle continues to shrink, which very often requires evaluation of circuit design and technology choices using circuit simulators at the time when no real silicon is available. In this paper, we present an efficient methodology for generating pre-silicon device models for advanced CMOS processes. The methodology allows accurate prediction of the full MOS I-V characteristics for the future technologies combining a constraint backpropagation algorithm based upon a few critical specifications, physical models for the advanced device phenomena, and the empirical data from devices of an existing technology. The methodology has been tested on two CMOS production technologies. Good prediction results are achieved: for nMOS the rms error is 1%-2%, for pMOS it is 2%-4%.

Dual collector magnetotransistors are magnetic-field-sensitive devices currently developed in several laboratories. Optimized sensor design is often attempted by trial and error rather than by established design rules. This motivated the present comprehensive study of the operation of magnetotransistors by accurate two-dimensional numerical simulations. We model vertical and lateral transistors as obtained by industrial IC technology on the basis of data provided by the chip manufacturer. We consider the entire device structure with the full, complex device geometry, and the physically proper boundary conditions. Our simulations reveal the details, controversial hitherto, of the operating principle of these devices. In particular we find that, in the case of the vertical transistor, it is essentially the emitter injection modulation effect which dominates the sensor response. In the case of the lateral transistor, the magnetic sensitivity is predominantly determined by minority-carrier deflection, although side effects are involved as well. By variation of the doping profile and the device geometry we derive rules for optimized magnetotransistor design. >