测定外延层电阻率的面接触方法研究

评论了美国科学家C.C. Allen等于1966年发表的“测定外延层电阻率的点接触方法”之论文的局限性,从而提出了本方法。本方法从理论上解一维Poisson方程并与C.C。Allen法的公式相比较,获得某些公式。文中导出了面接触方法雪崩击穿电压V_(Ba)~∞(V)及点接触方法雪崩击穿电压V_(Bp)~∞(V)的比值为V_(Ba)~∞=0.456;同时还导出了点接触方法外延层耗尽层宽度为t_(min p)(μm)和面接触方法外延层耗尽层宽度t_(mina(μm)的比值为t_(minp)/t_(mina)=2.565。在实践上,为证实两种模型的功能,利用两种探针进行了对比测试。一种是通常被采用的点接触锇尖探针:另一种是利用φ0.8±0.1mm的银针,在银针顶上吸上φ0.4±0.1mm的汞球,以实现面接触。理论和实验吻合良好。

The Research of the Area Contact Method for Evaluating Epitaxial Layer Resistivity

This paper reviews the limitation of the article "A Point Contact Method of Evaluating Epitaxial Layer Resistivity" by American scientist C. C. Allen et al. published in 1966,and provides a method. In this method,some formulas were theortetically obtained by solving the Poisson equation of one dimension and com-pared with the formulas off C. C. Allen's method. We derived the ratio of area contact avalanche breakdown voltage V(V) to point contact avalanche breakdown voltage V(V) , V/V= 0.456;and also we derived the ratio of point contact de-pletion layer width tminp(m) to area contact depletion layer width tmina(m) ,tminp/ tmina=2.565. In order to verify practical function of the two models,contrastive mea-surements were carried out with two types of probe. One type was an osmiumtipped probe forming point contact used in normal method. And the other was a 0. 80. 1 mm silver needie with plane, which absorbing φ0. 4 ± 0.1 mm mercury ball to form an area contact. The experimental results agree with the theory well.