金刚石对顶砧中触点位置误差对样品电阻率测量精度的影响

摘要

利用有限元分析方法,研究了金刚石对顶砧中电极与样品接触点位置变化对范德堡法测量样品电阻率精度的影响.结果表明：当电极中心与样品边缘的间距b≤d/9（d为样品直径）时能得到精确的电阻率测量结果;当电极位置远离样品边缘而逐渐接近样品中心时,其位置变化对电阻率测量精度的影响迅速增大;相同的电极位置变化对具有较大电阻率的半导体样品电阻率测量精度的影响更明显.%Using the finite element analysis,we study the effect of variation in pressure-induced electrode position on the measurement accuracy of the sample conductivity in diamond anvil cell with the Van der Pauw method.The results show that the electrode contact placement and electrode size play key roles in influencing the conductivity measurement accuracy.Theoretical computation reveals that the Van der Pauw method can provide an accurate result when the spacing between electrode center and sample periphery b is less than or equal to d/9 （d is the sample diameter）.Otherwise,the closer to the sample center of the contact location,the more rapidly the sample conductivity accuracy error increases.Such an effect is more significant for the semiconductor sample with high resistivity with the electrode position variation is the same.