ABSTRACT
Within semiconductor devices under external bias, the carriers experience successive scatterings while
traveling under the influence of an electric field. In most scattering events, they give up kinetic or
potential energy they retained, which is converted into various other forms of energy as a result of
generating phonons, photons, or electron-hole pairs. Among these energy-conversion modes, the
generation of phonons, or the increase of lattice vibration level, is the most frequently encountered
mode and results in the generation of heat in the devices. The consequent junction temperature rise, or
self-heating, significantly influences device behaviors. It modulates the device operation condition since
the characteristics of semiconductors are inherently given as a function of temperature. Device reliability
is also affected since the raised temperature promotes most of the long-term degradation mechanisms as
well as the catastrophic failures of the devices. Therefore, an accurate characterization of self-heating is
critical for the precise prediction of device operation and degradation as well as the prevention of device
failures. Historically, self-heating has been a concern mainly for high-power devices in which extensive
power consumption results in a great heat generation. However, recent aggressive scalings intended for
speed enhancement, which usually accompany a considerable increase in operation current level, have
made the self-heating in high-speed devices a major concern. Hence, self-heating has become a generic
issue for semiconductor systems in general, and their thermal properties need to be properly analyzed
along with the electrical properties.
