121st General Meeting of the KCS

Type Symposium
Area The World of Nanomaterials Viewed through the Windows of Physical Chemists
Room No. Room 402
Time FRI 09:25-:
Code PHYS2-2
Subject Giant Temperature Coefficient of Resistivity and Cryogenic Sensitivity in Silicon with Galvanically Displaced Gold Nanoparticles in Freeze-Out Region
Authors Jae-Won Jang*, Seongpil Hwang1
Department of Physics, Pukyong National University, Korea
1Department of Advanced Materials Chemistry, Korea University, Korea
Abstract The temperature coefficient of resistivity (TCR) and cryogenic sensitivity (Sv) of p-type silicon (p-Si) in the low-temperature region (10−30 K) are remarkably improved by increasing the coverage of galvanically displaced Au nanoparticles (NPs). By increase of the galvanic displacement time from 10 to 30 s, the average surface roughness (Ra ) of the samples increases from 0.31 to 2.31 nm and the coverage rate of Au NPs increases from 3.1% to 21.9%. In the freeze-out region of the sample, an up to 103% increase of TCR and dramatically improved Sv of p-Si (∼5813%) are observed with Au coverage of 21.9% compared to p-Si without galvanically displaced Au NPs. By means of a finite element method (FEM) simulation study, it was found that the increase of surface roughness and a number of Au NPs on p-Si results in a higher temperature gradient and thermoelectric power to cause the unusual TCR and Sv values in the samples.
E-mail jjang@pukyong.ac.kr