Mp. Houng et al., Heat generation approximation in modulation-doped field-effect transistorsby the energy relaxation between carriers and phonons, J APPL PHYS, 88(5), 2000, pp. 2553-2559
A combination of the nonlinear charge-control model, rate balance equations
, and electron-phonon scattering is used to simulate the hot-electron trans
port and heat generation problem of modulation-doped field-effect transisto
rs. Based on the present model, the trend of high-field transport can be we
ll demonstrated. In addition, the heat generation inside the channel can al
so be estimated by the energy flux balance equation with the energy relaxat
ion rate formulated by polar-optical phonon scattering mechanism. Scaling d
own the gate length to submicron range, more heat power is generated inside
the channel. However, the heat generation ratio reveals that hot electrons
carry over half of the energy density gained from the applied electric fie
ld directly into drain region. For 0.1 mu m gate length, more than 90% ener
gy density is achieved. By reducing the gate length into the deep submicron
range, the thermal impact on the drain side becomes more serious and compl
icated than the one found inside the channel. (C) 2000 American Institute o
f Physics. [S0021-8979(00)05417-7].