Thermoelectric performance in n-type bulk silicon: The influence of dopant concentration and dopant species
Thermoelectric performance in n-type bulk silicon: The influence of dopant concentration and dopant species
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DOI：
10.1002/pssa.201700307
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发表时间：
2017-07-01
影响因子：
2
通讯作者：
Bennett, Nick S.
中科院分区：
文献类型：
--
作者：
Bennett, Nick S.
硅（Si）最近受到热电（TE）应用的关注。对于所有TE材料，精确调整掺杂浓度仍然是最大化热电优值（ZT）的最简单方法。本文研究了n型Si在300 K下的热电性能，包括电阻率、热导率、Seebeck系数和霍耳迁移率的测量，以及掺杂浓度（N = 10（19）-10（20）cm（-3））和掺杂种类（P、As和Sb）对热电性能的影响。所有的属性被发现作为掺杂浓度和物种的函数而变化，导致对ZT的影响。掺杂P的Si的电阻率最低，掺杂Sb的Si的电阻率最高。对于塞贝克系数，情况正好相反。Sb掺杂的热导率最低，P掺杂的热导率最高。在所有情况下，As掺杂是中间掺杂剂。最佳掺杂浓度在类似于6- 7 × 10（19）cm（-3）的值处实现，并且对于As掺杂的Si和P掺杂的Si两者是类似的。对于Sb掺杂，最佳值可能是相似的，但商业上可获得的晶片中的最高掺杂类似于4x 10（19）cm（-3）。在300 K下，P掺杂的体硅实现了类似于0.010的ZT，然而最好的总体值是As掺杂的硅，类似于0.013。对于Sb掺杂，最佳值类似于0.012，尽管更高的值可能是可能的，但是只有当在起始衬底中可以实现掺杂水平大约是当前研究可用浓度的两倍时。这些结果为研究人员提供了有用的见解，他们正在为硅热电器件的自上而下的纳米结构方法选择起始衬底，其中需要具有优化ZT的晶片。(C)2017 WILEY-VCH Verlag GmbH & Co. KGaA，魏因海姆
Silicon (Si) has received recent interest for thermoelectric (TE) applications. For all TE materials, accurately tuning the doping concentration remains the easiest way to maximise the thermoelectric figure-of-merit (ZT). This study investigates the thermoelectric properties at 300K of n-type Si as a function of both dopant concentration (N similar to 10(19)-10(20)cm(-3)) and dopant species (P, As and Sb), including measurements of electrical resistivity, thermal conductivity, Seebeck coefficient and Hall mobility. All properties were found to vary as a function of both doping concentration and species, leading to impacts on the ZT. The electrical resistivity was lowest for P-doped Si and highest in Sb-doped Si. For the Seebeck coefficient, the situation was reversed. The thermal conductivity was lowest for Sb-doping and highest in P-doped Si. In all cases As-doping was the intermediate dopant. An optimum doping concentration was realized at a value of similar to 6-7x10(19)cm(-3), and is similar for both As- and P-doped Si. For Sb-doping, the optimum value is likely to be similar, but the highest doping in commercially available wafers was similar to 4x10(19)cm(-3). At 300K, ZT similar to 0.010 is achieved for P-doped bulk Si, however the best overall value was for As-doped Si, at similar to 0.013. For Sb doping the best value is similar to 0.012, though a higher value is likely to be possible, but only if doping levels approximately double the concentrations available for this current study can be achieved in starting substrates. These results provide a useful insight for researchers who are selecting a starting substrate for top-down nano-structuring approaches to Si thermoelectrics, where a wafer with optimised ZT is required. (C) 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim