Influence of Self-Heating Effect on I-V Dates of Party Depleted Submicron Silicon-on-Insulator CMOS Transistors at High Ambient Temperatures

To solve the problems of high temperature microelectronics the influence of the self heating effect on the IV dates partially depleted submicron silicon–on-insulator CMOS transistor in the ambient temperature range from 525 K to 650 K is discussed. Approach consists in combination of experimental data and of computational simulating results. For simulation of electrothermal characteristics of SOI CMOS transistor is considered three-layered structure. Temperature distribution is calculated numerically using iterative algorithm in conjunction with software COMSOL Multiphysics. I-V dates of SOI CMOS transistors are calculated by means of two-dimensional models for n-and p-channel transistors of Sentaurus TCAD developed in the system of instrument and technological modelling. TCAD models are calibrated on experimental characteristics for 525 K. It is shown that with growth of ambient temperature the selfheating mechanism contribution consistently decreases. By results of modeling it is established that self-heating contributions at supply voltages 5.5 V to decreases for ntransistor in 2.8 times, p-transistor in 2.2 times. The relative decline of current n-type transistor for reduced from 11.6% to 5.5% and for p-type with 15% to 9%. However, different dynamics of current recession for n-and p-transistors is significant for analog applications that need to be considered at high-temperature circuit design. The proposed methodology allows to critically assess the contribution of the self-heating mechanism on the I-V dates for a wide range of high temperatures and supply voltages. Underestimating this fact leads to unreasonable values for the maximum temperature and limit of thermal stability for the separate SOI CMOS transistor. In total this can be a prerequisite for a significant simplification of the design of not only the chip construction but also the whole electronic Board.