Dissemination of Metallic Contamination During IC Manufacturing

Abstract

The dissemination of metallic contamination occurring during wafer handling is of primary importance for the management of cross contamination issues. This work describes a protocol used to estimate the percentage of contamination transferred from a contaminated wafer to another one via contact on solid surfaces involved during handling. Results suggest that particles size is the most important parameter on the global cross contamination coefficient named K. For sub µm particles, the transfer is low, K ranging from 0 to 10%. Above a few µm, particles are very easily transferred from contaminated wafers to handling surfaces, with a coefficient K1 which can reach 100%. The decontamination of handling surfaces cycling clean wafers or using wet wipes has also been investigated. For situations leading to high K percentages, efficient and fast cleaning protocols can be applied. This work also discusses the interaction forces between particles and substrates to explain the observed tendencies.

Metallic Contamination Control in Leading-Edge ULSI Manufacturing

“…Therefore, effective contamination control coupled with adequate protocol has become essential in such production lines. The point of the protocol is minimization of damage caused by impurity metals diffused from these novel electronic materials [1][2][3][4][5]. In this paper, our strategy on cross-contamination control is discussed from the outset.…”