TTSV array can not only reduce the thermal concentration more efficiently, but also lower the probability of thermo-mechanical failure.
Tan, "Thermal mitigation using thermal through silicon via (TTSV) in 3D ICs," Int.
To obtain the temperature and thermal stress distribution of the improved TTSVs, the heat conduction and thermal stress equations should be solved numerically.
Both our N-FEM code and commercial FEM software ANSYS are run for the case of single-layer TTSVs with Fin mentioned below.
1 shows the schematic of single-layer TTSVs and extended three-layer TTSVs .
As the TTSVs with Fin structure get closer to the hotspot, the corresponding maximum temperature of single-layer TTSVs is obtained, as shown in Fig.
Here, three-layer TTSVs are modeled to study thermal coupling among heat sources in different layers of a 3-D stack.
Utilizing the temperature dependent properties of various materials listed in Table 1, nonlinear maximum temperature of three-layer TTSVs with overlapped hotspots and staggered hotspots are also provided in Fig.
9(a) and (b) demonstrate steady-state 3-D thermal stress distribution of single and three-layer TTSVs, respectively.
In our Fin structure model, Fin is connected to the liner of TTSVs. By replacing Si[O.sub.2] of liner with BCB, we get the maximum thermal stress for Si[O.sub.2] and BCB depending on the thickness of liner in Fig.