台面型InP/InGaAs PIN光伏探测器的p-InP低阻欧姆接触

研究了电子束蒸发淀积的非合金膜系Au/Pt/Ti/p-InP(2×1018cm-3)接触的物理特性,通过450℃、4 min的快速退火,获得了欧姆接触,其比接触电阻为7.3×10-5 Wcm2.接触电极退火后,采用离子溅射法淀积加厚电极Cr/Au.利用俄歇电子能谱(AES)进行深度剖面分析,表明Pt层能够相对有效地阻挡...

Low resistance ohmic contacts to p-InP of mesa-isolated InP/InGaAs PIN photovoltaic detectors

The electrical and metallurgical behavior of Ti/Pt/Au contacts on p-InP was investigated. The contacts were transformed to an ohmic contacts at the temperature about 450 ℃. Low resistance ohmic contacts (c=7.310-5cm2) were achieved after annealing at 450 ℃ for 4 minutes. To approach device process, Cr/Au (20 nm/400 nm) was deposited on the contact pads after the annealing process. The result indicates that the contacts of low resistance, smooth surface and high reliability are fabricated in a moderate condition. The auger electron spectroscopy(AES) depthcomposition profiles indicates that the Pt layer can relatively prevent Au from penetrating into the InP and only a small quantity of Au punched through the Pt layer and penetrated into the InP. The findings of the present study suggests that the formation of ohmic contacts on InP is controlled by chemical and metallurgical reaction between the contact metal and the InP layer, and a few InAux formations are beneficial to contact properties.