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We present SPICE simulations of a CMOS APS pixel element consisting of the optical sensor with the sensing circuit. The photodiode is simulated at the physics level by means of the so-called Generalized Devices, without any predefined compact model. Conversely, regular compact models are used for MOSFETs present in the circuit. Modeling with Generalized Devices takes into account in SPICE simulations both the layout and the physics of the photodiode, i.e., drift-diffusion transport, optical generation and recombination of excess carriers, capacitive effects and surface recombination. Moreover, electrical coupling between two adjacent pixels, i.e., the electrical crosstalk, is well predicted by the network of Generalized Devices. This approach is supported by TCAD Sentaurus simulations and opens the way to full SPICE simulation of Active Pixel Sensor from the circuit down to the semiconductor level within the same circuit simulation tool.

Transistors downsizing has made CMOS circuits sensitive to errors and dysfunction caused by radiation even at ground level. For this reason, accurate modeling of radiation effects is important for circuits design. In this work, we present a new approach for SPICE compatible simulation of charges and currents induced by ionizing radiation in silicon substrate. The approach is based on the so-called Generalized Lumped Devices, that simulate charge generation, propagation and collection using standard circuit simulators, without empirical or fitting parameters. The study of the effects of alpha particles at different energies impinging on a substrate of an IC is presented and the results obtained are validated with TCAD numerical simulations. This paper represents the first step towards accurate physics-based SPICE simulation of ionizing radiation effects in ICs.

We present a lumped devices network approach to simulate surface recombination effects in optoelectronics devices. The network is composed of generalized lumped devices where the excess carrier concentrations and gradients are mapped on electrical quantities, i.e. equivalent voltages and currents respectively, so that the overall simulation is SPICE-compatible. A novel enhanced device is derived and used as an additional element to account for the influence of the surface in SPICE-like simulations. Thus, in addition to generation, propagation and collection that were included in a former work, recombination at the surface of the semiconductor can be taken into account with standard circuit simulators. Optoelectronic devices performance degradation due to surface recombination is analyzed with this approach and compared with full numerical TCAD simulations.

SPlCE-compatible modeling with generalized lumped devices is used to simulate the spatial and time dependence of photogenerated carriers with standard circuit simulators. Equivalent voltages and currents are used in place of minority carrier excess concentrations and minority carrier currents respectively. The initial light-induced excess carrier concentration in silicon is accounted by means of distributed external voltage sources. Generation, propagation and collection of these minority carriers is analyzed for three pertinent structures and compared with TCAD numerical simulations.

We present SPICE simulations of a CMOS APS pixel element consisting of the optical sensor and the circuit. The photodiode is simulated at the physics level by means of the so-called generalized devices, without any predefined compact model. Conversely, regular compact models are used for MOSFETs. Modeling with Generalized Devices takes into account in SPICE simulations both the layout and the physics of the photodiode, that is drift-diffusion transport, optical generation and recombination of excess carriers, capacitive effects and surface recombination. This approach is supported by T CAD simulations and opens the way to full SPICE simulation of Active Pixel Sensor down to the semiconductor level.