Dynamic compact thermal models with multiple power sources: application to an ultrathin chip stacking technology

Compact Dynamic Modeling for Fast Simulation of Nonlinear Heat Conduction in Ultra-Thin Chip Stacking Technology

“…Nowadays, extremely dense modules are fabricated in UTCS technology, which exploits the recent advances in wafer thinning, as well as in attachment, bonding, and interconnection. In UTCS systems, multiple silicon chips thinned down to 10 μm are vertically integrated on a single (inactive) host silicon substrate, being the electrical insulation among them ensured by layers of benzocyclobutene (BCB), a photosensitive polymer with good planarization properties [11], [12], [29], [30]; the resulting stack provides larger circuitry integration than in 2-D ICs. Unfortunately, UTCS architectures may be subject to exacerbated thermal effects dictated by (i) the high power density and (ii) the low thermal conductivity of BCB (about 800 times lower than that of silicon), which inhibits the downward heat propagation from the power-dissipating regions to the board [11], [12], [30].…”

“…The large discrepancies between the results corresponding to the two cases A and B suggest that care must be taken in modeling the temperature dependence of the thermal conductivities of all materials belonging to the structure under test. 3) An inspection of the figure reveals the dramatic inaccuracy obtained by merely applying the Kirchhoff's transformation based on the law relating the thermal conductivity of Si to temperature, i.e., by using (12) with m = −1.33; in particular, R TH differs by ∼50% and ∼100% from the exact values associated to the nonlinear cases A and B. Including the further time variable transformation by Batty et al only a marginal improvement is gained for medium times, while the steady-state results remain unchanged.…”

Dynamic modelling for thermal micro-actuators using thermal networks

“…Thermal effects have an obvious impact in the performance and reliability of electronic systems and thermal devices [38]. Efforts to model the electrothermal actuators and thermal effects in electronic systems have been focused on analytical modelling, finiteelement methods, lumped parameters based on electrical analogy, and model order reduction.…”

“…These ordinary differential equations can then be simulated in acceptable time [60,61]. Palacin et al focus their attention to the development of compact thermal models from the analysis of the thermal impedance transients obtained from physical simulation (finite element model) [38]. Dynamic compact thermal models have been obtained for an ultrathin chip stacking technology where several chips can dissipate heat simultaneously.…”

Thermal properties of microscale inorganic light-emitting diodes in a pulsed operation

“…Several thermal models and approaches have been proposed to accurately and efficiently predict the LED temperature in a pulsed operation. Most of them are expressed as a thermal resistor-capacitor (RC) network, [8][9][10][11][12] which is solved by commercial or open programs such as FLOTHERM and SPICE. The RC network approach can save significant time and effort, but the values for R and C for different sections of LED packages need be determined from the curve-fitting of a transient thermal measurement of the package.…”