Mechanical behaviors of crust layer in high-dose ion implanted-photoresist (HDI-PR) upon exposure to atmospheric pressure oxygen plasma: A measuring “pop-in” point in nanoindentation

The use of existing processes for cleaning high-dose ion implanted-photoresist (HDI-PR) on semiconductor has some associated problems. When the PR surface is damaged by ion bombardment, its near surface changes to a hard layer called the crust layer. In this study, we suggest a nanoindentation-based method for measuring the “pop-in” point of force-depth graph of HDI-PR. It was observed that the thickness and load force of the crust layer decrease continually due to the atmospheric pressure plasma as the plasma treatment time increases from 0 to 120 s. Further, the mechanical property such as hardness or elastic modulus of the HDI-PR has changed suddenly after a treatment time of 60 s.