A Pragmatic Approach to Modeling Self-Heating Effects in SiGe HBTs

An approach for determining thermal resistance model parameters of SiGe HBT

“…The downward heat flow is assumed to be mostly through silicon. In fact, the negligible change in k of copper (from 300 to 600 K) can be ignored to presume a temperature‐independent k m . Therefore, the temperature dependent k can be modeled as follows: where β = 3.09 × 10 5 W·K α − 1 /m and α = 1.34 for intrinsic silicon material.…”

“…In fact, the negligible change in k of copper (from 300 to 600 K) can be ignored to presume a temperature-independent k m . 14,17 Therefore, the temperature dependent k can be modeled as follows 18 :…”

“…Before that, we need to be able to accurately estimate the thermal characteristics of the device. There are many methods [4][5][6][7][8][9][10][11][12][13][14] for measuring the self-heating phenomenon.…”

“…Then, the self-consistent iterative method for SiGe HBTs thermal resistance calculation is improved in the study of Balanethiram et al 10 This method evaluates both the upward and downward heat dissipation from the heat source located at the basecollector junction. Furthermore, a particularly interesting work reported in the study of Chakravorty et al 11 Chakravorty 14 reduced the method complexity using a linear approximation in a thermal resistivity model of silicon. Unfortunately, this method requires finding a particular value for a given technology and ambient temperature (T amb ), which increases the difficulty of calculation.…”

“…The work of Balanethiram et al presented a closed form solution but does not proposed a new method to solve the problem with R TH,m . A recent work of Yadav and Chakravorty reduced the method complexity using a linear approximation in a thermal resistivity model of silicon. Unfortunately, this method requires finding a particular value for a given technology and ambient temperature ( T amb ), which increases the difficulty of calculation.…”