金属/Hg1-xMnxTe接触的I-V特性研究

分别采用溅射和蒸发镀膜法在Hg1-xMnxTe试样表面形成了Au/Hg1-xMnxTe和Al/Hg1-xMnxTe接触,并用Aligent4155c I-V测试仪对其I-V特性进行了测量,随后对试样在10%NH4F:10%H2O2:H2O中进行了钝化处理,并对处理后的试样再次进行了I-V测量,对于测试结果用热电子发射-扩散理论进行了分析.结果表明:Au与Hg1-xMnxTe形成了良好的欧姆接触,而Al与Hg1-xMnxTe形成了具有整流特性的肖特基接触,其肖特基势垒的理论推算值为0.38eV.钝化处理后的试样,其表面漏电现象明显降低,Au/Hg1-xMnxTe接触的电流下降幅度在0.1V时最大,为76.1%;而Al/Hg1-xMnxTe接触在0.2V时最大,为93.2%.随着偏压的进一步增大,两种接触的电流减小的幅度都逐渐变小.

I-V characteristics of metal/Hg1-xMnxTe contact

Au/Hg1-xMnxTe and Al/Hg1-xMnxTe contacts were fabricated using sputter deposition(for Au) and thermal evaporation(for Al) methods respectively.I-V electronic characteristics of two contacts before and after passivation treatment were measured by Aligent4155c I-V tester.The experimental results were discussed based on thermionic emission-diffusion theory.The results show that Au/Hg1-xMnxTe contact are the ohmic contact,while Al/Hg1-xMnxTe are Schottky contact with the barrier height of 0.38eV.The surface leakage current decreases markedly after the passivation treatment.The highest current dropping rate was 76.1% at the forward bias voltage of 0.1V for Au/Hg1-xMnxTe, and was 93.2% at 0.2V for Al/Hg1-xMnxTe.The current dropping rate reduces with further increasing the bias voltage for both contacts.