It is very important to select superior interlayer pre-metal dielectric (PMD) materials that can act as a penetration barrier to various impurities created by the chemical mechanical polishing (CMP) process. In this paper, hot carrier degradation and device characteristics were studied on various materials of PMD-1 layers, which included low-pressure tetra-ethyl-ortho-silicate glass (LP-TEOS), Si-rich (SR)-oxide, plasma-enhanced (PE)-oxynitride, PE-nitride and PE-TEOS films. Pressure cooker test (PCT) analysis was used to obtain the electrical characteristics of devices, such as the shifts in threshold voltage and transconductance as a function of stress time, junction leakage current and breakdown voltage of field transistors with variation of these PMD-1 materials. Also, the most effective PMD-1 materials which can prevent degradation effects due to hot carrier stress were investigated. From experimental results, it is clearly shown that silicon oxide turned out to be a better PMD-1 material than both PE-oxynitride and PE-nitride. From the results, it is suggested that LP-TEOS film is the best PMD-1 material among the silicon oxide samples. © 2001 Kluwer Academic Publishers