Study on the effect of electron beam curing on low-K porous organosilicate glass (OSG) material

The effect of electron beam (e-beam) curing on an ultra low dielectric constant material, porous organosilicate glass (OSG) is investigated. In conventional IC integration processes, photoresist (P. R.) stripping with O2 plasma and wet chemical stripper is an inevitable step. However, dielectric degradation often occurs when low-k dielectrics undergo the PR stripping processing. This limits the application of incorporating low-k material into semiconductor fabrication. In order to overcome the integration issue, e-beam direct curing process was proposed in this study. In this technology, the dielectric regions irradiated by e-beam will be cross-linked, forming the desired patterns. Meanwhile, the regions without e-beam illumination are dissolvable in a mingled solvent of 2.38 wt.% tetra-methyl ammonium hydroxide (TMAH) and methanol with the ratio of 1:8. In this work, the possible doses of e-beam exposed porous OSG are decided by Fourier transform infrared spectroscopy, n&k 1200 analyzer and electrical analyses. The experimental results expressed that the minimum dosage to cure porous OSG film is 6 AC/cm, which is similar to commercial e-beam resist. Additionally, a scanning electron microscope FS.E.M.) image of homemade pattern was made to estimate the process practicability. D 2004 Elsevier B.V. All rights reserved.