Journal ArticleDOI
Temperature-dependent thermal conductivity of porous silicon
TLDR
In this paper, the thermal conductivity of electrochemically etched porous silicon (PS) layers was determined over a wide temperature range (T = 35 - 320 K) using the dynamic technique.Abstract:
The thermal conductivity of electrochemically etched porous silicon (PS) layers was determined over a wide temperature range (T = 35 - 320 K) using the dynamic technique. Both the doping level of the silicon wafers (p and ) and the porosity P of the porous layers (P = 64 - 89%) were varied. The measured thermal conductivities were three to five orders of magnitude smaller than the values for bulk silicon. Furthermore, they increase with increasing the wafer doping level and with decreasing the porosity P of the layers. For all investigated PS layers the thermal conductivity increases with temperature. The results are discussed in terms of a simple model for heat conduction in PS based on the phonon diffusion model.read more
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Journal ArticleDOI
Holey Silicon as an Efficient Thermoelectric Material
Jinyao Tang,Hung-Ta Wang,Dong Hyun Lee,Melissa Fardy,Ziyang Huo,Thomas P. Russell,Peidong Yang +6 more
TL;DR: In this article, the authors investigated the thermoelectric properties of thin silicon membranes that have been decorated with high density of nanoscopic holes and showed that by reducing the pitch of the hexagonal holey pattern down to 55 nm with 35% porosity, the thermal conductivity of HS is consistently reduced by 2 orders of magnitude and approaches the amorphous limit.
Journal ArticleDOI
Advances in thermoelectrics
TL;DR: In this article, a thermoelectric generator is used to directly convert heat into electricity, which holds great promise for tackling the ever-increasing energy sustainability issue in the future.
Journal ArticleDOI
Nanoporous Si as an Efficient Thermoelectric Material
TL;DR: It is found that while alignment of pores is necessary to preserve power factor values comparable to those of bulk Si, a symmetric arrangement is not required, indicating that nanoporous semiconductors with aligned pores may be highly attractive materials for thermoelectric applications.
Journal ArticleDOI
Frequency-dependent Monte Carlo simulations of phonon transport in two-dimensional porous silicon with aligned pores
TL;DR: In this paper, a boundary condition based on the periodic heat flux with constant virtual wall temperature is developed for the studied periodic structures, which enable the simulation of the lattice thermal conductivities with a minimum computational domain.
Journal ArticleDOI
Thermal conductivity of periodic microporous silicon films
D. W. Song,Gang Chen +1 more
TL;DR: In this paper, the experimental in-plane thermal conductivity of microfabricated, free-standing, single-crystal silicon thin films with periodically arranged through-film micropores was investigated.
References
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Journal ArticleDOI
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