Chemical Grafting Of Perfluorinated Organic Film On Silicon Surface In Aqueous Solution

With the rapid development of electronic industry,strict requirements for higher density and integration have been made to meet the demand of industrial production.Thus,electronic packaging technology has met new challenge.During recent years,through-silicon-via?TSV?of stacked chips is one of the key technologies of the industry and has provided constant innovation for the industry.However,it has been increasingly difficult for traditional method to prepare insular with high step coverage in smaller and deeper TSV.In the present research,the uniform and compact polymer film is prepared and strongly bonded to the Si substrate.Also,this chemical grafting method is applied to TSV with higher aspect ratio.It is shown that the thickness of the polymer film is uniform in TSV and the step coverage is almost 100%.Usually,the acrylic material is used in the chemical grafting.Perfluorinated monomer has many good properties such as good chemical stability,surface activity and broad temperature compatibility.It can be used as a replacement to investigate further about the insulation film properties.In this paper,the perfuorinated organic film is purposed of replace SiO₂ as insular.The perfluorinated film prepared on the Si surface was deeply investigated by X-ray photoelectron spectroscopy?XPS?,fourier transform infrared spectroscopy?IR?,ellipsometer,scanning electron microscope?SEM?and atomic force microscope?AFM?.The results shows that the uniform and compact perfluorinated film is prepared on the Si substrate by chemical grafting.The research contents and main conclusions are as follows:In the first part,the surface and cross-section morphology is studied.It is found that the thickness of the organic dielectric film increases with the increase of time,NBD concentration and monomer concentration.The film is uniform and transparent.When the grafting time is long enough or the monomer concentration is high,there will be crack or fall-off on the surface of the organic dielectric film.In the second part,the insulation properties and wetting abilities of the film are studied.It is found that the contact angle between organic dielectric film and pure water or C₂I₂.The contact angle between organic dielectric film and pure water increases when NBD concentration increases.The insulation properties and the contact angle between organic dielectric film and CH₂I₂ are of few differences.With the increase of monomer concentration,the insulation property will increase if there are no significant defects on the surface.If there are significant defects on the surface of the organic dielectric film,the insulation property will be bad.Also the contact angle between organic dielectric film and pure water will increase while the contact angle between organic dielectric film and C₂I₂remain the same.