【摘要】 作为一种洁净能源,硅锗合金的热电转换性能的研究越来越受到人们的重视。本文重点研究了不同Ge浓度的硅锗合金以及Si、Ge单晶在300～1100K温度范围内,Seebeck系数随温度的变化。并对组分相同导电类型不同、晶向不同以及结晶状态不同的样品的Seebeck系数进行了比较。在研究温度区间,Seebeck系数的绝对值大小一般在200～600μV/K之间,随温度不同连续变化。通过对比发现SiGe合金的Seebeck系数大小不仅与Ge的浓度和温度有关,其他因素对其绝对值也有影响,其中晶向最为明显,表现出了明显的各向异性。此外,材料本身的电阻率除了作为一个热电参数影响最优值外,其大小还对Seebeck系数的绝对值有影响,即掺杂济浓度对Seebeck系数的影响。更多还原

【Abstract】 To discuss the possibility of improvement in thermoelectric properties of SiGe crystal,the thermoelectric properties of several different silicon-germanium alloys with different content,different orientation and different electric conductive type at the temperature range of 300-1100K were investigated.As seen in the experiment result,the absolute value of Seebeck coefficient fluctuates in 200-600 μV/K in the whole temperature range investigated.In the present paper,the relationships of Seebeck coefficient against content,orientation,electric conductive type and electrical resistivity were summarized in detail.The Seebeck coefficient of the sample with <111> orientation is smaller than that of the sample with <100> orientation at the same temperature.Absolute value of P-type are larger than that of N-type,pure Ge except.But with the increasing of temperature,the absolute value of pure Ge decreased many times as quickly as other specimens.Moreover,electrical resistivity not only can influence the figure of merit,but also can influence the absolute of Seebeck coefficient.更多还原